Emergency department airway management-2026: EMAT clinical policy guideline

Abstract

This clinical policy was developed by Emergency Medicine Association of Türkiye (EMAT) to evaluate current evidence on airway management in the emergency department (ED) and to provide clinicians with practical, evidence based recommendations. Although rapid sequence intubation in the ED is a life saving intervention in critically ill patients, the choice of techniques and medications during its implementation has a decisive impact on patient safety and clinical outcomes. This policy was developed by the research committee (RC) using the “Grading of Recommendations, Assessment, Development, and Evaluations (GRADE)” methodology, based on systematic literature reviews and expert opinion. Within the framework of five key clinical questions, the following topics were examined: preoxygenation strategies (noninvasive mechanical ventilation, high flow nasal oxygen, face mask, and conventional techniques); the effectiveness and safety of apneic oxygenation; the use of a gum elastic bougie during intubation; the role of push dose vasopressors in patients at high risk of hypotension; and the safety of ketamine use in patients at risk of increased intracranial pressure. This policy aims to reduce complications related to airway management and improve patient outcomes by providing emergency physicians with an evidence based framework for preintubation preparation, medication selection, and equipment use.

Introduction

Airway management in the emergency department (ED), particularly rapid sequence intubation (RSI), is one of the most fundamental and highest priority interventions in the evaluation and treatment of critically ill patients. Unlike the operating room and intensive care unit (ICU), the ED is a dynamic, high stress environment that often lacks sufficient time for patient preparation, requiring rapid and accurate decision making. Under these conditions, establishing an effective and safe airway is of vital importance to prevent serious complications such as hypoxemia, cardiac arrest, and mortality.[1,2] To this end, numerous studies conducted in recent years have evaluated preintubation preoxygenation strategies, apneic oxygenation techniques, the use of high flow nasal oxygen (HFNO), the role of alternative induction agents, and the effectiveness of intubation adjuncts (rigid and flexible stylets, gum elastic bougie [GEB], etc.), generating ongoing debate regarding airway management practices in the ED.[3,4] However, most of these studies were conducted in different patient populations and under ICU or anesthesia conditions. Therefore, careful interpretation is required when applying these data directly to the ED setting.

This clinical policy guideline was developed during 2025–2026 by the Research Committee (RC) of the Emergency Medicine Association of Türkiye (EMAT) with the aim of providing evidence based answers to clinically important questions in ED airway management and guiding physicians across different clinical scenarios. Rather than adopting a perspective that encompasses all aspects of airway management or revisits questions with well established answers in the literature, this guideline focuses on emerging debates highlighted by recent studies.

Material and Methods

This clinical policy guideline was developed based on the “Grading of Recommendations, Assessment, Development, and Evaluations” (GRADE) approach and through evaluation of the evidence available in the literature.[5] When preparing the recommendations in the guideline, the level of evidence in the literature was taken into consideration. In cases where the evidence was insufficient or conflicting, the relevant clinical questions were answered through voting by the advisory board members of the RC, based on the principle of majority decision. The resulting clinical policy guideline was initially published on the EMAT and EMAT-RC websites, announced through social media, and published by EMAT-affiliated outlets. It was decided that EMAT-RC clinical policy guidelines would be routinely updated every 3 years, while allowing for earlier updates in the event of major developments.

Identification of clinical questions

Priority clinical policy topics to be developed were identified by the advisory board of EMAT-RC. Clinical questions related to the selected topics were collected from the field. For this purpose, announcements were made using the EMAT and RC websites and social media tools. Clinical questions were collected using Google Forms. Within the specified period (60 days), the collected clinical questions were voted on by 11 members of the EMAT-RC advisory board using a 9 point Likert scale according to the priority of the need to address the outcome (1–3: noncritical and unimportant outcomes; 4–6: noncritical but important outcomes; and 7–9: critical outcomes). As a result of the voting, noncritical but important outcomes and critical outcomes were considered appropriate to be answered using an evidence based approach.

Systematic literature search and article selection

For each identified clinical question, a systematic literature search was conducted in the SCOPUS, MEDLINE, and WOS databases using predefined keywords (search details are provided separately in the section corresponding to each clinical question).

Articles identified through the systematic literature search were uploaded separately into the Rayyan software for each clinical question.[6] Two independent, blinded reviewers evaluated whether the articles were relevant to the clinical question based on abstract review. Articles deemed appropriate were included for full text assessment, while those considered inappropriate were excluded. Articles for which the two reviewers had conflicting decisions were evaluated by a third reviewer, who made the final decision.

When performing meta analyses using data from primary studies, in cases where the reported effect size categories were not identical, the following approaches were preferred when possible: mathematical conversion of effect sizes, requesting the relevant effect size directly from the study authors, or using data from secondary publications in the form of systematic reviews that had previously used the primary studies and reported the relevant effect size.

Classification of evidence

For each critical question, critical appraisal of the studies included in the review was performed by at least two researchers, and evidence grading was conducted using the GRADEPro software in accordance with the GRADE approach (very low, low, moderate, and high level of evidence). Risk of bias assessment was performed using the RoB 2 tool for randomized controlled trials (RCTs), while observational studies were directly considered to be at high risk. Risk of bias assessment was carried out by two blinded reviewers; studies for which the reviewers had conflicting judgments were evaluated by a third reviewer, who made the final decision.

Determination of recommendation levels from levels of evidence

Recommendations were developed according to the appropriate levels of recommendation based on the evidence tables generated using the GRADE approach. Accordingly, the levels of recommendation are presented as shown in Table 1.

Table 1. Levels of recommendation

This clinical policy guideline is intended as a recommendation document for physicians working in EDs. The patient population includes adult patients presenting to EDs, while pediatric patients are excluded from the scope of the guideline. EMAT RC clinical policy guidelines reflect the official position of EMAT RC, as they provide evidence based answers and recommendations derived from the current literature. However, they do not constitute definitive or absolute recommendations for physicians. EMAT RC respects physicians’ clinical experience and patients’ preferences when final decisions are made.

As a result of the panel voting, all five clinical questions addressed in this guideline were categorized as “noncritical but important questions,” and none were classified as a “critical question.”

Noncritical But Important Clinical Questions

Noncritical but important clinical questions and their evidence based answers are presented in detail below, along with a discussion of the literature. A summary of all the recommendations included in this clinical policy
is shown in Supplementary File 1.

Scenario 1

During the preoxygenation phase of RSI in the ED, is there a difference in oxygenation success (incidence of severe hypoxia) among noninvasive mechanical ventilation (NIV), HFNO, face mask, and conventional techniques [Table 2]?

Table 2. Scenario‑1

Rationale and background

In the RSI procedure in EDs, it is undesirable for patients to remain hypoxic during the period until a definitive airway is secured. To reduce this risk, administration of oxygen for several minutes before the procedure is recommended; this practice is referred to as preoxygenation. The aim of this intervention is to increase pulmonary oxygen reserves and subsequently reduce the development of hypoxia during procedural interventions. While the most common practice involves patients receiving oxygen therapy through nasal cannula or face mask, alternative methods such as NIV and HFNO have increasingly been used during the preoxygenation phase in recent years. In this guideline, the effectiveness and safety of preoxygenation methods used during the RSI procedure in critically ill patients with an indication for intubation in the ED are evaluated based on evidence, with the goal of providing recommendations to emergency physicians regarding which method is more effective and reliable.

Study selection

In studies comparing preoxygenation methods, highly heterogeneous scenarios exist due to methodological differences in the intervention arms. To answer the relevant clinical question, only well defined clinical studies that compared different oxygen delivery methods specifically during the preoxygenation period were considered throughout the guideline development process. Nevertheless, studies with differing designs regarding oxygen administration are also present in the literature. In some studies, the oxygen delivery methods preferred during the preoxygenation process were not limited to the preoxygenation period and were also continued during the apneic oxygenation phase. In other studies, oxygen support was provided only during the preoxygenation phase or only during the apneic phase, with no oxygen administration during the other phase. To provide a clear answer to the relevant clinical question, studies that compared different oxygen delivery methods solely during the preoxygenation phase and did not apply any oxygenation during the apneic period were ultimately included for evaluation, and the data from these studies were used to perform meta analyses and included in effect size pooling.

Because the keywords of studies comparing preoxygenation methods and those comparing apneic oxygenation are very similar, and due to a lack of conceptual clarity in the existing literature, a common literature search was performed for both topics, and the articles were subsequently classified into two main categories through rapid abstract screening. Accordingly, a total of 119 articles were identified as a result of the systematic literature search conducted using the relevant keywords [Supplementary File 2; located at the end of the document]. From these articles, observational studies, studies not related to the clinical question, pediatric studies, and – as mentioned above – studies in which different oxygen therapy modalities were applied not only during the preoxygenation phase but also thereafter(during the apneic period) were excluded. The remaining five RCTs were included in the final evaluation. All of these RCTs were studies that compared methods providing oxygen therapy exclusively during the preoxygenation phase [Supplementary File 3].[7-11]

Four RCTs that provided oxygen support during both the preoxygenation and apneic oxygenation phases and did not meet the inclusion criteria specified above, but were considered to be indirectly related to the topic, were additionally discussed at the end of this section under the heading “Other relevant articles”.

In the risk of bias assessment performed using the Cochrane RoB 2 tool for studies with a randomized clinical trial design, a moderate-risk-of-bias was identified in four articles,[7-10] while a high risk of bias was identified in one article[11] [Figure 1]. Summaries of the studies are presented in Supplementary File 4.

Figure 1. Traffic light plots of randomized clinical trials comparing preoxygenation methods during rapid sequence intubation in the emergency department (RoB 2 risk of bias assessment)

Overview of the studies and outcome measures

When the clinical settings of the studies are examined, the majority are noted to have been conducted in ICUs; four studies were performed in the ICU, while one study was conducted in both the ICU and the ED. The two studies by Baillard et al. [7,10] published in 2006 and 2018 were conducted in hypoxic patients, whereas the study by Guitton et al. [8] was conducted in patients without severe hypoxemia. The study by Gibbs et al. [9] was conducted in patients described as severely ill; however, the definition of “severely ill patient” was not explained in detail in the article. Among the included studies, only the study by Li et al. [11] was conducted in a patient population requiring emergency surgery.

In the studies, the standard treatment arms included oxygen support delivered through face mask (nonrebreather face mask in one study) and bag valve mask (BVM). In the study by Li et al.,[11] the standard treatment arm did not include a BVM, and oxygen was administered using a face mask only. In three of the five RCTs, NIV was used in the intervention arm, while HFNO was used in the remaining two studies.[7-11]

A wide variety of outcomes, often differing substantially from one another, were addressed across the studies. In many studies, mean/median SpO₂ values at the end of the RSI procedure in both arms, the lowest SpO₂ values, or oxygen values before and after preoxygenation were compared. However, the clinical significance of these outcomes is limited. When supplemental oxygen is administered to any patient, an increase in postintervention values compared with baseline is already expected; therefore, pre–post comparisons have very limited clinical value in this context. Similarly, comparing mean/median SpO₂ values between the two arms at the end of intubation carries limited clinical relevance. Small differences that may be statistically significant but clinically insignificant can be negligible for clinicians. For example, a mean SpO₂ value of 96% in one arm versus 94% in the other, even if statistically significant, may be considered to have a negligible impact on clinical decision making and patient centered outcomes. In this context, the incidence of severe hypoxia in the treatment arms was considered the primary clinically meaningful outcome, and the meta analysis focused on this endpoint. As many studies defined severe hypoxia as SpO₂ < 80% or 85%, this threshold was adopted in the clinical policy. Although of limited clinical significance, the lowest SpO₂ values during intubation were also included as a secondary outcome for the meta analysis.

Other outcomes were not included in the meta analyses either because they were not considered clinically meaningful or because they could not be analyzed in a poolable manner across studies. Outcomes that were not suitable for pooling but were considered clinically relevant were additionally discussed on a study by study basis.

Occurrence of severe hypoxia (SpO₂ < 80%/85%) during intubation

In this guideline, the occurrence of severe hypoxia during the procedure, rather than clinically negligible decreases in oxygen saturation, was accepted as the most critical and clinically meaningful outcome. Of the four studies reporting this outcome, three compared NIV with a face mask (standard oxygen therapy) or face mask + BVM,[7,9,11] while one study compared HFNO with standard oxygen therapy.[8] In two of the three studies in which NIV was used in the intervention arm,[7,11] the control group included a nonrebreather mask + BVM, whereas in one study, the control group included either BVM or face mask alone, and it was emphasized that even in patients who received BVM, no active ventilation was performed.[9] Due to differences between the treatment arms, the meta analysis was performed using stratification: in the subgroup analysis comparing the NIV intervention arm with the standard treatment arm and including three studies, a significantly lower incidence of severe hypoxia was observed in favor of NIV, with a notably large effect size (odds ratio [OR]: 0.40, 95% confidence interval [CI]: 0.28–0.59). Preoxygenation with NIV reduces the odds of severe desaturation by approximately 60% compared with a standard face mask. The absolute benefit was approximately 7%, meaning that one episode of severe hypoxia is prevented in 1 of every 14 patients.

Only one study, by Guitton et al.,[8] compared HFNO with standard therapy, and although a marked benefit in favor of HFNO was mathematically apparent in this study, it was not statistically significant (OR: 0.25, 95% CI: 0.05–1.25). Due to the presence of a single study and a small sample size, statistical confidence regarding the isolated effect of HFNO could not be established.

When the pooled overall effect of the four studies was examined, a significantly lower incidence of severe hypoxia during preoxygenation was observed in favor of the intervention arm (NIV or HFNO) (OR: 0.39, 95% CI: 0.20–0.57). The low to moderate heterogeneity (I² ≤ 39%) suggests that the results are consistent [Figure 2].

Figure 2. Forest plot showing the results of the meta‑analysis of randomized clinical trials comparing the incidence of severe hypoxia (SpO2 <80%/85%) with different preoxygenation methods during rapid sequence intubation in the emergency department. IV: Inverse variance, CI: Confidence interval

Lowest SpO₂ level during intubation

In three RCTs, the lowest SpO₂ levels during intubation were reported and were considered suitable for pooled analysis. Among these, the studies by Baillard et al. [7,10] and Gibbs et al. [9] compared NIV with face mask, while the study by Guitton et al. [8] compared HFNO with face mask.[6-10] In the study by Gibbs et al.,[9] the data were reported as median and interquartile range (IQR); therefore, these data were converted to mean and standard deviation according to the formula proposed by Luo et al. [12] and included in the analysis.

All three RCTs had a moderate-risk-of-bias. Although there was a mathematical trend in favor of the intervention arm (NIV/HFNO) in both the comparison of NIV versus face mask (mean difference: 6.76, 95% CI: 2.28–15.81) and the comparison of HFNO versus face mask (mean difference: 2.0, 95% CI: 0.69–4.69), no statistically significant difference was observed. However, when the pooled effect of both intervention arms was examined, a statistically significant benefit in favor of the intervention arm was identified (mean difference: 3.92, 95% CI: 0.78–7.05). Based on this, it can be considered that the lack of statistical significance in subgroup analyses according to treatment arms may be attributable to small sample sizes [Figure 3].

Figure 3. Forest plot showing the meta‑analysis of the lowest SpO2 values reported in three randomized clinical trials comparing intervention arms using NIV or HFNO for preoxygenation with a standard face mask during rapid sequence intubation in the emergency department, demonstrating a trend toward higher lowest SpO2 levels in favor of the intervention arm in the combined analysis. IV: Inverse variance, CI: Confidence interval, SD: Standard deviation

Inhospital mortality, aspiration, regurgitation, and risk of reflux

Among the preoxygenation studies, no study reported periresuscitative mortality. Instead, because the studies were predominantly conducted in intensive care settings, inhospital mortality was reported, and we consider this outcome to be not clinically meaningful with respect to NIV/HFNO therapies. This is because it is difficult to attribute a mortality occurring perhaps days after the intubation procedure to the treatment arms. Nevertheless, in all three RCTs that reported inhospital mortality, no significant difference between the treatment groups was reported.[8-10]

When comparisons were attempted in terms of aspiration risk, it was observed that the studies did not provide poolable data. The intervention groups were compared with respect to aspiration outcomes in two studies, regurgitation risk in two studies, and reflux risk in one study. Although these outcomes are similar, they do not reflect exactly the same clinical condition and therefore were not considered as composite outcomes. In addition, considering the methodological differences between the intervention arms, the existing literature was not suitable for meta analysis with respect to these outcomes, and the studies were evaluated individually for these adverse effect outcomes.

In the study by Baillard et al. [10] published in 2006, no significant difference in regurgitation was detected between the intervention groups (NIV vs. BVM + face mask) (1 [4%] vs. 2 [8%], P = 1). In the 2018 study by the same authors comparing the same treatment arms, both groups were again reported to be similar in terms of regurgitation risk (NIV: 0 [0%], control group: 1 [2.2%]).[7] In the study by Gibbs et al.,[9] some patients in the control group received a face mask alone, while others additionally received BVM; however, no active ventilation was performed. In this study, no statistically significant difference in aspiration was detected between the treatment arms (NIV: 6 [0.9%], control group: 9 [1.4%], risk difference: 0.4, 95% CI: 1.6–0.7). In the study by Guitton et al.,[8] which compared HFNO with face mask, no aspiration was reported in the HFNO group, whereas aspiration was reported in two patients in the control group (P = 0.15). Finally, in the study by Li et al. [11] (HFNO vs. face mask), no reflux was reported in either treatment arm.

The lack of statistically significant differences between groups in terms of mortality as well as aspiration, regurgitation, or reflux outcomes may be due to small sample sizes; alternatively, particularly for mortality, which is a multifactorial outcome, it is also possible that despite reducing severe hypoxia, these interventions did not demonstrate an effect on mortality. While these results may be interpreted as indicating no meaningful benefit in secondary outcomes, they may also be interpreted as showing that the intervention arms were at least not harmful with respect to these outcomes.

Other safety outcomes

Although other adverse event–complication outcomes were reported in the studies, most were not suitable for pooling and were therefore discussed separately on a study by study basis.

In the study by Baillard et al. [10] published in 2006 comparing NIV and standard face mask, no differences were found between groups in terms of new infiltrates on postprocedure chest radiography, duration of mechanical ventilation, length of ICU stay, or ICU mortality. In a similar study by Baillard et al. [7] published in 2018, the incidence of adverse events was reported as 21.4% in the NIV group and 28.7% in the face mask group, with no significant difference (P = 0.24). In the same study, no significant difference was observed between groups in terms of the number of ventilator free days within 28 days after intubation. Likewise, the number of days spent outside the ICU was also reported to be similar between groups.

Similarly, in the study by Gibbs et al. [9] that compared NIV and face mask, the incidence of new opacities on chest radiography and the incidence of pneumothorax were reported to be similar between the two study groups. No differences were detected between groups in SpO₂ and FiO₂ levels measured 24 h after intubation.

In the study by Guitton et al. [8] that compared HFNO and face mask, the duration of mechanical ventilation was found to be similar between the HFNO and standard face mask groups (3 [2–6] days and 3 [2–7] days, respectively; P=0.80). During intubation, at least one intubation related complication occurred in 6 patients (6%) in the HFNO group and in 17 patients (19%) in the standard treatment group, with the HFNO group found to be more favorable in terms of complications (relative risk (RR): 0.31, 95% CI: 0.13–0.76; P = 0.007).[8]

In the study by Li et al.,[11] which was the only RCT among the included trials with a high risk of bias, the groups were reported to show no differences in other complications such as nasopharyngeal bleeding, postoperative pulmonary infection, postoperative nausea and vomiting, and postoperative nasopharyngeal pain.

In conclusion, across nearly all safety outcomes, neither NIV nor HFNO therapies, were reported to have adverse effects compared with standard treatment, and both methods can be considered safe with respect to these outcomes.

Articles indirectly related to the clinical question

Because oxygen support was provided during both the preoxygenation and apneic periods, four RCTs could not be evaluated for their isolated effect under either heading and were therefore not included in the metaanalyses. Nevertheless, as they applied treatments similar to the other studies during both phases and thus provide indirect evidence, they are discussed separately below. Of these studies, two were assessed as having a low-risk-of-bias, one a moderate-risk-of-bias, and one a high risk of bias.[13-16]

The study by Chua et al. [13] was conducted in the ED on 192 patients with an indication for RSI for any reason, comparing oxygenation with HFNO and a nonrebreather face mask. The median lowest SpO₂ was calculated to be similar in both groups (100%). The incidence of SpO₂ dropping below 90% (incidence of hypoxia) was lower in the intervention group compared with the control group (15.5% vs. 22.6%, RR: 0.68, 95% CI: 0.37–1.25). The incidence of ventilator associated pneumonia and aspiration pneumonia was reported to be similar in both groups. Overall, the groups were found to be comparable with respect to all complications.[13]

The study by Frat et al.,[14] conducted in ICU patients with acute hypoxemic respiratory failure, provided highly valuable data in terms of comparing HFNO and NIV interventions used in the intervention arms of other studies. In this multicenter study, including 313 cases from 28 centers, analysis of the entire patient cohort showed that the incidence of severe hypoxemia (SpO₂ <80%) was similar between the HFNO and NIV groups. However, according to subgroup analysis of 242 patients with moderate to severe hypoxemia (PaO₂ /FiO₂ ≤200mmHg), severe hypoxemia occurred less frequently in the NIV group compared with the HFNO group (24% vs. 35%, OR: 0.56, 95% CI: 0.32–0.99; P = 0.046). Serious adverse events did not differ between the treatment groups.[14]

In the study by Karlupia et al.,[15] which included patients who underwent RSI for abdominopelvic emergency surgery, oxygenation with HFNO was compared with face mask oxygenation. No statistically significant differences were identified between the two groups in terms of postintubation PaO₂ values, lowest SpO₂ , apnea duration, number of laryngoscopy attempts, use of any rescue maneuvers, or adverse effects (P > 0.05). The study authors emphasized that the two methods were similar across all outcomes and highlighted that HFNO was at least as safe as face mask oxygenation.[15]

In the study by Tarigonda et al.,[16] which was the only RCT among the four articles with a high risk of bias, the effectiveness of NIV (continuous positive airway pressure) and nasal cannula oxygen administration was compared in ICU patients with hypoxemic type 1 respiratory failure. The lowest SpO₂ values observed during intubation were found to be similar between groups. However, the degree of desaturation (the difference between SpO₂ after preoxygenation and SpO₂ during intubation) was calculated to be worse in favor of the nasal cannula group (nasal cannula: 4.24 ± 3.67 vs. NIV: 2.10 ± 3.50, P = 0.007). Intubation duration and complication rates were reported to be similar between the two groups.[16]

In summary, these four studies yield results that are largely consistent with those of the other studies. Both HFNO and NIV demonstrate outcomes that are either comparable to or superior to oxygen delivery through face mask or nasal oxygen. In addition, all methods appear to be similar in terms of adverse effects, indicating that they are safe. Although it is difficult to conclude, based on the available evidence, that NIV and HFNO have a clear superiority over one another in the intervention arms, NIV appears to be slightly more advantageous, particularly in patients with severe hypoxemia.

Conclusion

Considering the available results, the use of NIV instead of a standard face mask for preoxygenation is associated with a reduced risk of severe hypoxia. Given that no differences were observed in safety outcomes such as mortality and aspiration, preferring NIV over a standard face mask or BVM for preoxygenation – particularly in critically ill patients – appears reasonable in terms of reducing the incidence of severe hypoxemia.

Although the evidence is insufficient to draw definitive conclusions regarding the use of HFNO instead of a standard face mask/BVM for preoxygenation, HFNO therapy may provide a potential benefit. When the study by Frat et al. [14] that compared NIV and HFNO is considered, the possibility that HFNO may be at least as effective as NIV is increased. There is also no difference in safety outcomes compared with a standard face mask. In addition, because HFNO technically allows continuation of oxygenation during the apneic period, it may be considered as an alternative option for preoxygenation.

In conclusion, the overall body of evidence indicates that in patients at high risk of hypoxia, preoxygenation with NIV before emergency RSI significantly and clinically meaningfully reduces the incidence of severe hypoxia and is safe with respect to adverse effects, particularly mortality and aspiration risk. Although HFNO demonstrates a similar trend, definitive evidence is lacking. Taking available resources and patient characteristics into account, NIV may be considered the first line option in clinical practice, while HFNO may be considered an alternative when NIV is not feasible.

GRADE evidence classification tables demonstrating the levels of evidence of the included studies are presented in Supplementary File 5.

Research gaps

Most studies are single center. Blinding is particularly difficult to achieve for this research topic, and this limitation may influence outcomes. It is observed that outcome assessor blinding was either not ensured or not reported in the studies. The fact that the majority of studies were conducted in ICUs limits the generalizability of the results. There is a need for RCTs conducted in EDs in which outcome assessor blinding is ensured. In addition, studies targeting specific subgroups – such as hypoxic versus nonhypoxic patients, obese patients, and those with or without heart failure or respiratory failure – would be beneficial to allow more selective application of these interventions. Considering ease of application and the current paucity of evidence, there is a greater need for studies evaluating the effectiveness of HFNO.

Although both HFNO and NIV appear to be safe with respect to safety outcomes, it should not be overlooked that the lack of differences between groups in terms of aspiration risk may be related to insufficient sample sizes or methodological differences among studies. In this context, there is a need for further evaluation with higher quality RCTs to reassess whether BVM and NIV increase the risk of aspiration.

Scenario 2

During RSI in the ED, is apneic oxygenation - used in addition to standard preoxygenation - an effective and safe treatment option in terms of the incidence of severe hypoxia (SpO2 < 80%) and the lowest SpO₂ value [Table 3]?

Table 3. Scenario‑2

Rationale and background

During the performance of RSI procedures in EDs, particularly in critically ill patients, hypoxemia is the most important complication that can lead to mortality.[17-20] To avoid this complication, preoxygenation has traditionally been applied using various methods before induction, with the aim of replenishing oxygen reserves for potentially prolonged apneic periods.[3,20] However, especially in critically ill patient populations – most notably those with predominant respiratory failure – preoxygenation alone may be insufficient and may contribute to morbidity and mortality.[3] For this reason, in recent years, studies have been published investigating the effectiveness of administering oxygen during the apneic period (the interval from induction until passage of the endotracheal tube through the vocal cords), in addition to preoxygenation, when performing RSI procedures in critically ill patients in ED and ICU settings. This method, defined as apneic oxygenation, has in fact been applied for many years through placement of a cannula in the nasopharyngeal region or through a nasal cannula placed in the nostrils. With the widespread availability of HFNO devices, this therapy has regained popularity. However, review of the literature reveals differing opinions and findings among studies addressing this topic.[21-27] In this guideline, the aim is to provide evidence based recommendations regarding the use of apneic oxygenation in addition to preoxygenation during RSI procedures for emergency physicians encountering critically ill patients with an indication for intubation in the ED.

Study selection

Because the keywords of studies comparing preoxygenation methods and those comparing apneic oxygenation are very similar, and due to the lack of standardized concepts and definitions in the existing literature, a common literature search was conducted for both topics, and the articles were subsequently classified into two main categories through rapid abstract screening. Accordingly, a systematic literature search using the relevant keywords [Supplementary File 2] identified a total of 89 articles related to apneic oxygenation. Among these, a total of 79 studies were excluded because they had non RCT study designs despite the availability of sufficient RCTs on the topic, were not related to the clinical question, or involved populations other than ED or critically ill patients. The remaining 10 RCTs were included in the final evaluation [Supplementary File 3].

In the risk of bias assessment performed using the Cochrane RoB 2 tool for studies with a randomized clinical trial design, five articles were identified as having a lowrisk-of-bias, four as having a moderate-risk-of-bias, and one as having a high risk of bias [Figure 4]. Summaries of the studies are presented in Supplementary File 4.

Figure 4. Traffic light plots of randomized clinical trials evaluating apneic oxygenation applied in addition to standard preoxygenation during rapid sequence intubation in the emergency department (RoB 2 risk of bias assessment)

Overview of the studies and outcome measures

When the clinical settings of the studies are examined, three studies were conducted in critically ill patients with an indication for RSI in the ED,[21-23] while four studies were conducted in patients with an indication for RSI in the ICU.[24-27] The remaining three studies were conducted in patient populations with an indication for intubation due to emergency surgical indications.[28-30]

When the efficacy outcomes of studies conducted in ED and ICU patients are examined, all reported the lowest SpO₂ values during intubation as the primary outcome, and in addition, except for the study by Shahul Hameed et al.,[24] the number of patients experiencing severe desaturation was also reported in the remaining six studies. Although the lowest SpO₂ value was recorded as the primary outcome in these studies, the panel preferred to base discussions and recommendations primarily on the outcome of “incidence of severe hypoxia,” as it was considered to have greater clinical significance in this guideline. Effect sizes for both outcomes were pooled through meta analysis in all but one of the studies.

Although all studies included in the meta analysis primarily investigated the effect of apneic oxygenation administered in addition to preoxygenation, different preoxygenation techniques were also used in four studies.[24-27] Therefore, this represents a potential confounding factor affecting outcomes. For this reason, stratification was applied during meta analysis, with three studies that used similar preoxygenation methods grouped into one subgroup[21-23] and four studies with different preoxygenation methods grouped into a separate subgroup. For preoxygenation, techniques such as BVM, nonrebreather face mask, and noninvasive ventilation were used in the included studies. For apneic oxygenation, HFNO was the most commonly used method, although nasopharyngeal oxygen and standard nasal cannula oxygen were also used.

In most studies conducted in patients with emergency surgical indications, the presence of respiratory distress or low baseline SpO₂ values was defined as an exclusion criterion. Therefore, these studies have the potential to provide only indirect evidence for the clinical question being addressed. In addition, in most of these studies, the outcome measure was defined as PaO₂ rather than SpO₂ , and thus, they were not included in the meta analysis. The results of these three articles were discussed separately.

Occurrence of severe hypoxia (SpO₂ <80%) during intubation

When the results of the meta analysis pooling data from 693 patients across six studies reporting this outcome[21,22,24-27] were examined, it was found that apneic oxygenation used in addition to preoxygenation did not result in a significant reduction in the incidence of severe hypoxia compared with the control group (preoxygenation alone) (OR: 1.14, 95% CI: 0.70–1.86; P = 0.59). Subgroup analyses based on whether preoxygenation techniques were similar or not also demonstrated that apneic oxygenation applied in addition to preoxygenation did not provide a significant reduction in the incidence of severe hypoxia compared with preoxygenation alone [Figure 5].

Figure 5. Forest plot showing the meta‑analysis results of randomized clinical trials comparing apneic oxygenation applied in addition to standard preoxygenation with preoxygenation alone, in terms of the incidence of severe hypoxia (SpO2 <80%) during rapid sequence intubation in the emergency department. ED: Emergency department; M‑H: Mantel–Haenszel method, CI: Confidence interva

Although none of the studies conducted for emergency surgical indications reported severe hypoxia (SpO₂ < 80%), in the study by Lodenius et al.,[29] five patients (12.5%) were reported to have desaturated to below 93% in the control group, whereas no desaturation was observed in the group receiving apneic oxygenation with HFNO.[29] Mir et al. [28] reported that no patients in either group experienced desaturation below 90%.[28]

Lowest SpO₂ recorded during intubation (lowest SpO₂ )

When the results of the meta analysis pooling data from 769 patients across seven studies reporting this outcome were examined, it was observed that apneic oxygenation used in addition to preoxygenation did not result in a significant difference in the lowest SpO₂ values recorded during intubation compared with preoxygenation alone (mean difference: 0.10, 95% CI: 1.02–1.22, P = 0.87). Subgroup analyses based on whether preoxygenation techniques were similar or not also showed that apneic oxygenation did not result in a significant difference in the lowest SpO₂ values observed during the RSI procedure compared with preoxygenation alone [Figure 6].

Figure 6. Forest plot presenting the meta‑analysis results of randomized clinical trials comparing apneic oxygenation applied in addition to standard preoxygenation with preoxygenation alone, in terms of the lowest SpO2 values recorded during the procedure during rapid sequence intubation in the emergency department. SD: Standard deviation, IV: Inverse variance, CI: Confidence interval

Among studies conducted in patients who underwent intubation due to emergency surgical indications, only the study by Lodenius et al. [29] reported the lowest SpO₂ values and demonstrated no significant difference between the treatment arms.[29] In the study by Preya et al.,[30] the lowest SpO₂ value was not reported; instead, the lowest arterial PaO₂ measured during the apneic period was reported, and arterial PaO₂ values were shown to be higher in the group receiving apneic oxygenation with HFNO compared with the group receiving preoxygenation alone.[30]

Mortality and other adverse outcome measures

When all studies are evaluated, it is observed that different studies reported different adverse event- safety outcomes. Therefore, pooling effect sizes for these outcomes was not preferred; instead, selected outcomes were discussed separately on a study by study basis. With respect to mortality outcomes, Caputo et al. [22] compared 24 h mortality between treatment arms, while four studies compared 20–30 day mortality; however, none demonstrated a statistically significant difference.[21,24,25,27] In four studies, first pass intubation success was compared, and no significant difference was shown between the two treatment arms.[21,22,24,28] Cırıl et al. [27] investigated intubation duration as a secondary outcome and reported no significant difference.[27]

In conclusion, across all secondary outcomes–including the safety outcomes reported by the studies themselves–apneic oxygenation applied in addition to preoxygenation was not found to differ from preoxygenation alone.

Conclusion

Considering the results of RCTs evaluating the effectiveness of apneic oxygenation applied in addition to preoxygenation during RSI procedures – particularly in critically ill patients in the ED – it is observed that apneic oxygenation does not result in a difference in terms of the incidence of severe hypoxia or the lowest measured SpO₂ values. Similarly, apneic oxygenation does not lead to additional deterioration in secondary outcomes such as mortality, first pass intubation success, and intubation duration. When interpreting the results of the studies, it should be taken into account that four of the studies included in the meta analysis also differed in their preoxygenation methods, representing a potential confounding factor. Considering that the remaining studies – those evaluating the pure effect of apneic oxygenation with identical preoxygenation methods – had limited total sample sizes, we believe that larger studies with uniform preoxygenation methods are needed. GRADE evidence classification tables demonstrating the levels of evidence of the included studies are presented in Supplementary File 5.

Research gaps

The studies are single center with small sample sizes, and preoxygenation methods are generally not standardized. Therefore, there is a need for large sample studies in which preoxygenation methods are the same in both arms. In particular, there is a priority need for studies evaluating HFNO therapy in the apneic oxygenation arm, given its ease of applicability.

Scenario 3

During intubation in the ED, does the use of a GEB, compared with standard intubation (with or without a stylet), increase first attempt intubation success and affect intubation duration [Table 4]?

Table 4. Scenario‑3

Rationale and background

In airway management in the ED, first pass success of endotracheal tube placement is a critical quality indicator, as multiple intubation attempts are independently associated with severe hypoxemia, aspiration, and cardiac arrest during intubation. Some clinicians do not use any facilitating instrument during endotracheal tube placement. However, although the use of a stylet is the default adjunct to facilitate tube passage in many centers, an increasing number of emergency physicians are using the GEB as a primary or rescue device. Owing to its small external diameter and preshaped distal angulation of 35°–40°, the GEB may facilitate tube passage in situations with limited laryngeal visualization. Nevertheless, within the unique context of the ED – characterized by variable operator experience, high illness severity, and frequent physiologic deterioration – whether these theoretical advantages translate into measurable improvements in first pass success and procedure duration is decisive for widespread adoption of the device. This clinical policy guideline aims to evaluate, in an evidence based manner, the effects of GEB use during RSI compared with standard intubation (with or without a stylet), particularly with respect to first pass success and procedure duration.

Study selection

A systematic literature search using the relevant keywords [Supplementary File 2] identified 942 articles. Of the 186 articles related to the research question, 18 had an RCT design, while the remaining articles were observational studies. Given the sufficient number of RCTs, observational studies were not included [Supplementary File 3].

Of the 18 RCTs, manikin studies, animal and cadaver studies, studies using modified stylets/tracheal tubes, and studies involving mixed procedures conducted with additional adjunctive devices such as video laryngoscopy (VL) were excluded, and 11 RCTs were included for evaluation. In contrast, studies in which additional adjunctive methods not specified in the protocol were used at the clinician’s discretion were not excluded.[12,31-42]

In the risk of bias assessment performed using the Cochrane RoB 2 tool for RCTs, 6 studies were identified as having a high risk of bias, 1 study a moderate risk, and 4 studies a low-risk-of-bias [Figure 7]. Summaries of the included studies are presented in Supplementary File 4.

Figure 7. Traffic light plots of randomized controlled trials comparing the use of a gum elastic bougie with standard intubation (with or without a stylet) during intubation in the emergency department (RoB 2 risk‑of‑bias assessment)

Overview of the studies and outcome measures

When the clinical settings of the studies were examined, it was notable that the patient population predominantly consisted of operating room patients. Less frequently, the remaining studies were conducted in the ED, ICU, and prehospital settings. In all studies, GEB was used in the intervention arm. In the comparator arm, the use of a stylet was reported in 6 studies, while in 5 studies, it was not explicitly stated whether a stylet was used. Instead, the comparator arm was described as the standard treatment/intubation arm. In the analyses, all of these studies were grouped into a single comparator arm and evaluated as the standard intubation arm (with or without a stylet).

When focusing on studies with low and moderate-riskof-bias, 3 studies were conducted under operating room conditions,[31,34,36] The 2018 study by Driver et al. [33] was conducted in the ED, while their 2021 study included both ED and ICU patients.[32,33] Of the studies with a high risk of bias, 5 were conducted in the operating room,[35,38-41] whereas only the study by Heegaard et al. [37] was conducted in the prehospital setting.[37]

First attempt intubation success

Among studies with low/moderate-risk-of-bias, of the 4 studies analyzing first attempt intubation success, three reported no statistically significant difference, while only the 2021 study by Driver et al. [32] reported a statistically significant result in favor of GEB.[32] In the meta analysis of these 4 studies, although the pooled effect appeared to favor GEB numerically, this effect was not statistically significant (OR: 1.36, 95% CI: 0.49–3.76). For the same outcome, among the 6 studies with high risk of bias, 3 studies – by Gataure et al.,[35] Sut et al.,[41] and Khan et al. [38] – reported a statistically significant benefit in favor of GEB, while the remaining studies reported no significant difference; the pooled effect of the high risk of bias studies demonstrated a marked benefit in favor of GEB (OR: 4.18, 95% CI: 2.39–7.29). When considering the overall pooled effect of all 10 RCTs (low , moderate , and high risk of bias) addressing this outcome, GEB was associated with a statistically significantly higher first attempt intubation success rate (OR: 2.34, 95% CI: 1.14–4.80) [Figure 8]. Although the overall pooled effect of the 10 RCTs favors GEB for first attempt intubation success, it should be noted that this benefit is largely driven by studies with high risk of bias, whereas the pooled effect of low risk of bias studies did not demonstrate a statistically significant difference.

Figure 8. Forest plot showing the meta‑analysis results of first‑attempt intubation success in randomized clinical trials comparing the use of a gum elastic bougie with standard intubation (with or without stylet) during emergency department intubation, stratified according to the risk of bias of the studies. IV: Inverse variance, CI: Confidence interval

In the stratified meta analysis performed according to the clinical settings in which the studies were conducted, the overall pooled effect across all strata again demonstrated higher first attempt intubation success in favor of GEB(OR: 2.03, 95% CI: 1.10–3.74). However, when studies were stratified by clinical setting, it was notable that the benefit in favor of GEB was predominantly derived from prehospital and operating room studies, most of which had a high risk of bias [Figure 9]. In contrast, studies with low and moderate-risk-of-bias conducted in the ED or ICU did not report a benefit in favor of GEB, and ED data in particular were conflicting. In the 2018 study by Driver et al.,[33] a statistically significant advantage was observed with GEB (98% vs. 87%).[33] However, in the 2021 study by the same authors, there was no significant difference between treatment arms (80% vs. 83%), and the intubation time was on average 12 s longer in the GEB group.[32] Although the meta analysis overall suggests a trend in favor of GEB, the CIs are wide, and heterogeneity is substantial. In this context, while a potential benefit of GEB for first attempt intubation success appears plausible, it should be emphasized that results from RCTs with good methodological quality and low-risk-of-bias do not support this finding. In addition, methodological differences and certain limitations across studies may have influenced the results. In both the 2018 and 2021 studies by Driver et al.,[33] the use of VL was not standardized and was left to the clinician discretion. In the 2018 study, VL was used significantly less frequently in the GEB arm compared with the control group, which was considered an important methodological limitation. Unequal distribution of a confounder, such as VL use between treatment arms, may have influenced the results. Notably, despite less frequent VL use, outcomes favored GEB, suggesting that the true beneficial effect of GEB may be greater than the reported effect.

Figure 9. Forest plot showing the results of a stratified meta‑analysis of randomized clinical trials comparing the use of a gum elastic bougie with standard intubation (with or without a stylet) during intubation in the ED, stratified by clinical setting, for first‑attempt intubation success rates

When focusing exclusively on studies conducted in patients with a difficult airway, the statistically significant and pronounced benefit of GEB is noteworthy. Across studies with low/moderate as well as high risk of bias, both stratified analyses and the overall pooled effect demonstrate that GEB significantly increases first attempt intubation success (OR: 2.11, 95% CI: 1.47–3.01) [Figure 10].

Figure 10. Forest plot showing the results of a meta‑analysis of randomized clinical trials comparing the use of a gum elastic bougie with standard intubation (with or without a stylet) for first‑attempt intubation success in difficult airway cases in the emergency department. M‑H: Mantel–Haenszel method, CI: Confidence interval

In conclusion, although GEB may be associated with a statistically significant improvement in first attempt intubation success across all patients, large studies with low-risk-of-bias do not confirm this finding. Therefore, while a potential benefit of GEB in this scenario appears plausible, it remains debatable. However, when focusing on patients with a difficult airway, the approximately twofold increase in the odds of first attempt intubation success with GEB is noteworthy, and the benefit of GEB in this subgroup can be stated with greater confidence.

Overall intubation failure

Most studies reported first attempt intubation success or the total number of attempts as outcomes. The limited number of studies reporting overall intubation failure generally defined overall failure as the absence of successful intubation after two attempts and/or failure to achieve successful intubation within >60 s, and we likewise defined overall intubation failure accordingly. Among the studies reporting overall failure rates, the study by Ghai et al. [36] was assessed as having a moderaterisk-of-bias, while the other three studies were assessed as having a high risk of bias.[31-34] In the meta analysis, no difference was observed between treatment arms in the Ghai et al.’s[36] study with low or moderate-riskof-bias (OR: 2.11, 95% CI: 0.36–12.24), whereas the pooled results of the three studies with high risk of bias demonstrated a statistically significantly lower overall intubation failure rate in the GEB group (OR: 0.21, 95% CI: 0.06–0.68). When the overall pooled effect of all studies was considered, although a numerical benefit in favor of GEB was observed, this benefit was not statistically significant (OR: 0.39, 95% CI: 0.09– 1.62) [Figure 11].

Figure 11. Forest plot showing the results of a meta‑analysis of randomized clinical trials comparing the use of a gum elastic bougie with standard intubation (with or without a stylet) for overall intubation failure rates during intubation in the emergency department. IV: Inverse variance, CI: Confidence interval

In addition to the meta analysis, when study specific results are examined, noteworthy findings emerge. For example, in the study by Gataure et al.,[35] all patients in the standard treatment arm who could not be intubated after two attempts were successfully intubated using a GEB as a rescue intervention.[35] Similarly, in the 2018 study by Driver et al.,[33] among a total of 56 patients in whom first attempt intubation failed in both arms (48 patients in the standard intubation arm and 8 patients in the GEB arm), 49 were successfully intubated using a GEB as a rescue intervention.[33] In both studies, the preferential use of a GEB as a rescue intervention after failed attempts, and the fact that the majority of these interventions resulted in successful intubation, is noteworthy.

Endotracheal intubation time

Although first attempt intubation success is the most critical outcome in RSI protocols in the ED, the duration of the intubation procedure is another important quality indicator. Increased intubation duration has been shown to be associated with hypoxemia and periresuscitative arrest.

Among the RCTs included in the analysis, 8 reported intubation times for GEB and standard intubation. In 6 of these studies, intubation times were reported as mean and standard deviation, whereas in the two studies by Driver et al.,[32,33] times were reported as median and IQR. Although attempts were made to contact the authors by e mail to request the data as mean and standard deviation, no response was obtained. Therefore, intubation times in these two studies were recalculated as mean and standard deviation using the formula proposed by Luo et al.,[12] and these values were included in the meta analysis.[12]

Marked differences in reported intubation times across studies are notable and are thought to be related to the lack of standardization in the definition of intubation time. In most studies, detailed information on how this duration was measured was not clearly described. Of the 8 studies, 5 had low/moderate-risk-of-bias, and when the pooled effect of these studies was examined, the standard intubation arm was found to have a statistically significantly shorter intubation time. Although the pooled effect of the 3 studies with high risk of bias did not demonstrate a significant difference between groups, inclusion of these studies resulted in an overall pooled effect across all 8 studies indicating a statistically significantly shorter intubation time in favor of standard intubation (mean difference: 3.7 s, 95% CI: 1.02–6.38). However, considering the 95% CI, this disadvantage – ranging between 1 and 6 seconds – has debatable clinical implications and may be regarded as a limited negative effect for GEB. While this time difference may be relevant in hypoxemic patients, it is likely to be clinically tolerable for the general patient population [Figure 12].

Figure 12. Forest plot showing the results of a meta‑analysis of randomized clinical trials comparing the use of a gum elastic bougie with standard intubation (with or without a stylet) for endotracheal intubation time during intubation in the emergency department. SD: Standard deviation, IV: Inverse variance, CI: Confidence interval

Complications

A wide range of outcomes were evaluated as complications across the studies, and some studies did not report any complication data. Because no outcomes were suitable for meta analysis, this section was discussed on a study by study basis.

In four studies, treatment arms were compared with respect to the complication of esophageal intubation, and all reported similar rates between groups.[31,36-38]

In the 2021 study by Driver et al.,[32] the rate of cardiovascular collapse within 1 h was reported to be statistically significantly higher in the standard intubation arm (91 [16.7%] vs. 68 [12.2%]; absolute difference: 4.4, 95% CI: 0.1–8.8).[32]

Because complication related outcomes were defined differently across studies, very few studies reported overlapping complication data. When studies were examined individually, treatment groups were reported to be similar with respect to laryngospasm, stridor, airway obstruction, airway mucosal trauma, SpO₂ < 80%, witnessed aspiration, newly developed pneumothorax, sore throat, hoarseness, lip laceration, dental trauma, and hypoxemia related complications.[31,34,36-39]

Conclusion

The available evidence indicates that, compared with standard intubation, GEB is associated with a statistically significant benefit in first attempt intubation success, particularly in patients with a difficult airway, although it is also associated with a modest prolongation of intubation time. When interpreting these results, it should be noted that the studies are heterogeneous, especially with respect to first attempt intubation success, and that the meta analyses are therefore sensitive to this heterogeneity; the potential benefit appears to be driven largely by prehospital and operating room studies. GRADE evidence classification tables summarizing the certainty of evidence for the included studies are presented in Supplementary File 5.

In patients with a difficult airway (defined as Cormack– Lehane Grade III view or the presence of vomitus, bleeding, deformity, etc., around the airway), GEB provides a clear and meaningful benefit, and the use of GEB during RSI should be preferred over standard intubation (with or without a stylet) in these patients. In patients in whom standard intubation is selected as the initial approach and the first attempt is unsuccessful, GEB may be considered as a rescue intervention.

Although a benefit in first attempt intubation success rates in favor of GEB can be suggested, there is insufficient strong evidence to support the routine use of GEB in all patients. However, considering that patients in the ED – unlike those in operating room or ICU settings where most studies were conducted – often present with much more rapidly evolving clinical scenarios, virtually every ED patient may be regarded as a potential difficult airway case. Taking this into account, together with the favorable safety profile of GEB in terms of complications, we recommend preferring GEB over standard intubation (with or without a stylet) across the entire patient population. Nevertheless, for GEB to be used routinely during RSI in all patients, it is essential that personnel in the relevant clinical settings have received adequate training in the use of GEB.

Research gaps

There is a need for ED focused, multicenter RCTs to investigate differences in first attempt tube passage success. In existing studies, the lack of a standardized definition for “tube placement time” is notable; this concept should be standardized, and the comparison between GEB and standard intubation should be repeated accordingly. In addition, RCTs specifically focusing on obese patients, trauma patients, and physiologically critically ill patients are needed to enable subgroup analyses in these populations.

Scenario 4

In adult patients in the ED who are hypotensive or at high risk of hypotension, does the administration of push dose vasopressors (VPs) (phenylephrine, epinephrine, etc.) during or immediately before RSI, in addition to standard treatments, improve the incidence of peri intubation hypotension and clinical outcomes [Table 5]?

Table 5. Scenario‑4

Rationale and background

RSI performed in critically ill patients in the ED may be associated with a risk of hemodynamic instability. The sedative and paralytic agents used during this process can lead to abrupt decreases in blood pressure and impaired organ perfusion. This risk may increase morbidity and mortality, particularly in patients who are at high risk of hypotension.[42,43]

In clinical practice, some clinicians may prefer the use of push dose VPs during or immediately before RSI to mitigate this risk. Agents such as phenylephrine and epinephrine are commonly favored because of their rapid onset of action and feasibility for peripheral administration.[44,45] However, data in the literature regarding the efficacy and safety of this approach are limited. In recent years, a meta analysis including 24 RCTs demonstrated that prophylactic administration of push dose VP before orotracheal intubation was associated with higher postintubation mean arterial pressures and systolic arterial pressures (mean difference: 7.6 mmHg, 95% CI: 4.3–10.8).[46] Nevertheless, this study focused entirely on elective intubations performed in the operating room in American Society of Anesthesiologists physical status I–II patients and therefore provides only very limited indirect evidence for the use of this approach during RSI in critically ill patients who are already hypotensive.

This guideline aims to provide evidence based recommendations regarding the use of push dose VPs during RSI for emergency physicians managing critically ill patients in the ED who are hypotensive or at risk of hypotension and have an indication for RSI.

Study selection

As a result of the systematic literature search conducted using the relevant keywords, a total of 98 studies were identified [Supplementary File 2]. Of these, 7 studies evaluating the use of push dose VP during the peri intubation period in critically ill patients who were hypotensive or at risk of hypotension were included for assessment. In these studies, phenylephrine was most commonly used as the VP; however, because this agent is not available in our country, three additional observational studies evaluating the efficacy of push dose VP in clinical scenarios other than the peri intubation period, and assessing epinephrine – which is more readily available locally – in addition to phenylephrine, were also included. These studies were considered in the recommendation development process because they provided comparative data on the efficacy and safety profiles of sympathomimetic agents such as phenylephrine and epinephrine [Supplementary File 3]. All included studies were observational in design, and no separate tool was used for risk of bias assessment; instead, because most were single arm observational studies, all were considered to have a high risk of bias. Summaries of the studies are presented in Supplementary File 4.

Overview of the studies and outcome measures

There are no RCTs that directly compare the use of push dose VP during RSI in critically ill patients at risk of hypotension. Instead, the majority of the studies included for evaluation consist of observational studies or secondary analyses of previously conducted RCTs.

Studies evaluating the effectiveness of push dose vasopressors during the peri intubation period

Of the seven studies evaluating the effectiveness of push dose VP during the RSI procedure, five were single arm observational studies with limited sample sizes.[47-51] In all of these studies, changes in vital signs – primarily blood pressure – before and after push dose VP administration were assessed. When the results were evaluated, it was generally observed that clinically meaningful increases in blood pressure (approximately 10–20 mmHg) were achieved after administration compared with baseline. However, adverse events such as arrhythmias and rebound hypertension were also reported at varying frequencies within these patient series. Because these studies lacked comparator arms, it is not possible to determine with certainty whether these adverse event rates – and similarly the observed effectiveness – were attributable specifically to push dose VP administration.

One of the remaining two studies was a secondary analysis reported by Fuchita et al.,[52] based on cohorts from two previously conducted RCTs.[52] In this study, two groups – those who did and did not receive push dose VP – were created using propensity score matching to evaluate the effectiveness of push dose VP. The authors reported that hypotension occurred more frequently in the group in which a VP infusion was initiated after push dose VP compared with the group that did not receive any VP (53% vs. 41%, P = 0.02). However, as also noted by the authors, this finding may primarily reflect substantial selection bias. In both underlying RCTs, no standardized protocol for VP use was defined; instead, the decision to initiate VP therapy was left to the clinician discretion. Therefore, despite the use of propensity score matching to mitigate this bias, it is possible that patients who received VP were inherently more severely ill, which may have driven this result.

The final study evaluating the effectiveness of push dose VP during RSI was the retrospective study by Schmitt et al.,[53] which was based on a secondary analysis of 2 years of intubation registry data.[53] In this study, bolus, infusion, and combined (bolus + infusion) VP administration groups created using propensity score matching were compared. The rate of poor outcomes was reported to be lower in the bolus VP group compared with the other two groups (80% vs. 88%; P < 0.01).

In most of the evaluated studies, phenylephrine was used. When dosing and frequency were assessed, phenylephrine was generally prepared by adding 1000 µg of phenylephrine to a 10 mL syringe to obtain a concentration of 100 µg/mL. The most commonly described approach in the literature involves administering a 100–200 µg phenylephrine bolus (1–2 mL of the prepared solution), followed by repeat dosing after 1–2 min if needed. However, this agent is not widely available in Türkiye. Therefore, the effectiveness of push dose epinephrine, which can be used as an alternative to phenylephrine in Türkiye, was discussed by additionally including the studies summarized below.

Studies evaluating the use of push dose epinephrine and phenylephrine in non–peri intubation scenarios

In two separate studies evaluating data from ICU and ED patients who were hypotensive and critically ill and received push dose phenylephrine or epinephrine for the management of hypotension, both agents were reported to produce significant increases in blood pressure; however, in both studies, the magnitude of this effect was greater with epinephrine than with phenylephrine.[54,55] However, in the study by Singer et al.,[54] epinephrine was reported to be associated with a higher incidence of adverse effects such as hypertensive episodes and tachycardia. In the study by Nam et al.,[55] dosing errors were reported to occur more frequently with epinephrine than with phenylephrine. Finally, in the study by Nawrocki et al.,[56] epinephrine administered as bolus therapy in critically ill hypotensive patients was reported to increase blood pressure to a clinically acceptable extent, while a lower rate of adverse events (approximately 2%) was reported compared with other studies. [56]

When the doses used were evaluated, all studies reported the administration of 10–20 µg (1:100,000) bolus epinephrine every 2 min.

Conclusion

The current literature provides insufficient evidence regarding the efficacy and safety of push dose VP use. Although the panel has chosen not to issue a recommendation on this topic, it is a reality that push dose VP therapy is used in some clinician dependent practices. Based on this, the panel considers that, in critically ill patients who are hypotensive or at risk of hypotension, the decision of whether to administer push dose VPs during the RSI procedure should be determined by each institution according to its own local clinical policy. If a local clinical policy decision is made to administer push dose VP, the route of administration and dosing recommendations should be clearly specified in that policy. The recommended dosing varies depending on the selected agent (phenylephrine or epinephrine); however, in the available studies, dose ranges of 100–200 µg for phenylephrine and 10–20 µg for epinephrine have been used. Because phenylephrine is not widely available in Türkiye, low dose epinephrine, which can provide similar hemodynamic responses, may be used as an alternative. If implemented, the panel recommends administering epinephrine at a dose of 10 µg, intravenously, as a push dose over 1 min.

Scenario 5

In the ED management of adult patients at risk of increased intracranial pressure, is the use of ketamine during RSI a safe option [Table 6]?

Table 6. Scenario‑5

Rationale and background

Severe acute brain injury (ABI) is frequently encountered in the ED in conditions such as traumatic brain injury, subarachnoid hemorrhage, intracerebral hemorrhage, acute ischemic stroke, and hypoxic brain injury, and due to the potential for increased intracranial pressure (ICP), the risk of secondary cerebral injury and poor prognosis is always present in this patient population.[57] In the ED management of patients with severe ABI, RSI is often required both to protect the airway and to prevent secondary brain injury. Among the induction agents commonly used during RSI in the ED is ketamine, an N methyl D aspartate receptor antagonist. However, based on the findings of a few historically limited studies, the concern that ketamine may increase ICP remains widespread among clinicians.[58,59] Although several more recent studies have reported findings contrary to this concern, differing opinions persist regarding the use of ketamine during RSI, particularly in patients with severe ABI.[60,61] This guideline aims to provide evidence based recommendations regarding the use of ketamine as an induction agent during RSI for emergency physicians managing patients with acute ABI in the ED. This guideline does not compare effectiveness across different clinical conditions.

Study selection

A systematic literature search conducted using the relevant keywords [Supplementary File 2] identified 85 articles. Of these, a total of 18 articles relevant to the research question were included for final evaluation; 7 had an RCT design, while the remaining 11 were observational studies [Supplementary File 3, at the end of the document].

Although all observational studies were considered to have a high risk of bias, the risk of bias assessment performed using the Cochrane RoB 2 tool for the RCTs demonstrated that all 7 RCTs also had a high risk of bias [Figure 13]. In answering the relevant clinical question, RCTs were taken as the primary evidence base; however, due to issues of indirectness related to population and outcomes in these studies, the main findings of the observational studies were also taken into consideration. Summaries of the included studies are presented in Supplementary File 4.

Figure 13. Traffic light plots of randomized clinical trials evaluating the use of ketamine during rapid sequence intubation in patients with acute brain injury at risk of increased intracranial pressure (RoB 2 risk‑of‑bias assessment)

Overview of the studies and outcome measures

None of the RCTs or observational studies fully address our research question. In none of the available RCTs were patients who were at risk of increased ICP and underwent RSI directly defined as the study population. Instead, in five RCTs, the effects of ketamine administered as a continuous infusion for sedation on ICP were evaluated in intubated patients with ICP elevation due to ABI.[61-65] In four of these five studies, ketamine administered as a continuous infusion for sedation was compared with opioids (fentanyl or sufentanil) also administered as continuous infusions [Figure 14a]. Similarly, in four studies, continuous ICP monitoring through intraventricular catheters was performed and reported in all patients. As common outcomes suitable for meta analysis, ICP and CPP values measured at the end of the 1^st day of infusion were accepted. Based on the meta analysis results, ketamine infusion administered for sedation did not have an adverse effect on ICP or CPP compared with opioid infusion (for ICP: mean difference: 0.78 mmHg, 95% CI: 1.87 0.31; for CPP: mean difference: 1.07 mmHg, 95% CI: 7.95–5.80) [Figure 14b].

Figure 14. Forest plots showing the meta‑analysis results of randomized clinical trials comparing the effects of ketamine infusion versus opioid infusion used for sedation on intracranial pressure (a) and cerebral perfusion pressure (b) in intubated patients with acute brain injury and elevated intracranial pressure. SD: Standard deviation, IV: Inverse variance, CI: Confidence interval

In the RCT conducted by Burman et al.,[65] intubated patients with severe ABI (GCS < 8) who were sedated with fentanyl and midazolam were randomized to receive additional sedation with a ketamine infusion or placebo.[65] In both treatment arms, continuous monitoring of ICP and CPP was performed through an intraventricular catheter throughout the 36 h infusion period. The authors reported that ICP values in the ketamine group generally tended to be lower than those in the placebo group, with this difference reaching statistical significance at the 4–6 h time points. Similarly, CPP values were generally higher in the ketamine group, and this difference was also statistically significant during the 4–6 h interval. Because the study did not report overall mean ICP and CPP values, its data could not be included in the meta analysis.

Although their study populations do not directly represent patients with established intracranial hypertension, the results of two RCTs were also considered in this guideline, because both studies involved direct measurement of ICP and reported early postketamine ICP data in a manner analogous to the early phase of an RSI procedure.[66,67] In the study by Ben Yehuda et al.,[67] published in 2006, a total of 39 pediatric patients undergoing lumbar puncture (LP) for suspected meningitis were randomized to receive either ketamine + midazolam or midazolam alone for procedural sedoanalgesia.[67] The primary outcome was the post LP opening pressure. The ketamine + midazolam group demonstrated a higher opening pressure compared with the midazolam only group (24.4 ± 8.87 mmHg vs. 20 ± 3.74 mmHg). Similarly, in the RCT conducted by Michalczyk et al.,[66] sedation regimens were compared in 25 pediatric oncology patients undergoing a total of 84 LP procedures as part of their diagnostic follow up.[66] Patients were assigned to one of three sedation strategies: ketamine + midazolam, propofol + fentanyl, or ketamine alone. The primary outcome was again post LP opening pressure. In this study, the group receiving ketamine alone had significantly higher opening pressure values compared with the other two groups.

Eleven observational studies evaluating the effects of ketamine in ABI patients with suspected increased ICP were also assessed in this guideline. In seven of these studies, the study population consisted of patients with ABI who underwent RSI, and ketamine was compared with other agents as an induction agent. Although ICP or cerebral perfusion pressure were not defined as outcome measures in any of these studies, ketamine was reported to have no more adverse effects compared with other agents in the reported outcomes, including mortality, neurological outcomes, first pass intubation success, and hemodynamic parameters.[68-73] Only in the study by Fouche et al. [74] was a higher incidence of postintubation hypotension reported in the ketamine group.[74] In the remaining four observational studies, patients undergoing RSI were not specifically defined as the study population; instead, the effects of ketamine used for sedation in intubated ABI patients were evaluated by monitoring ICP changes with continuous ICP monitoring. When the main results of these studies were examined, either no significant change in ICP and cerebral perfusion pressure values was observed, or ketamine was reported to have a favorable effect, particularly on cerebral perfusion pressure values.[75-78] [Supplementary File 4].

Conclusion

As discussed in detail above, although the available studies are at high risk of bias and most were not conducted in an RSI scenario, there is no evidence to suggest that intravenous ketamine causes a greater increase in ICP compared with other agents or worsens neurological or other clinical outcomes in patients with ABI and suspected elevated ICP. Only two studies conducted in a pediatric population without ABI reported higher LP opening pressures. Therefore, we believe that there is no need to specifically avoid the use of ketamine as an induction agent during RSI in this patient group. However, clinicians should take into account that the available evidence is highly indirect and that there are no low risk of bias RCTs conducted in patients at risk of increased ICP undergoing RSI. GRADE evidence certainty tables for the included studies are presented in Supplementary File 5.

Supplementary Files are available online at https://turkjemergmed.com/pages/2026-3-issue-supplementary-files

How to cite this article: Çorbacıoğlu SK, Aksel G, Bayram B,Aksay E, Danış F, Doğan FS, et al. Emergency department airway management-2026: EMAT clinical policy guideline. Turk J Emerg Med 2026;26:159-82.

Authorship provides credit for a researcher’s contributions to a study and carries accountability. All authors listed in this manuscript fulfil the authorship criteria recommended by the International Committee of Medical Journal Editors (ICMJE). Each author has made substantial contributions to the conception and/or design of the work; or the acquisition, analysis, and/or interpretation of data; or the creation of new software used in the work; or has drafted the work or substantively revised it for important intellectual content.
All authors have approved the submitted version (and any substantially modified version that involves the author’s contribution to the study) and agreed to be personally accountable for their own contributions. In addition, all authors ensure that questions related to the accuracy or integrity of any part of the work, even those in which the author was not personally involved, are appropriately investigated, resolved, and documented in the literature.
CRediT roles: ŞKÇ: Conceptualization ( equal ) ; data curation (lead); investigation (lead); methodology (equal); project administration (equal); software (equal); supervision (equal); validation (lead); visualization (equal); writing – original draft (equal); writing – review and editing (lead). GA: Conceptualization (equal); data curation (supporting); formal analysis (lead); investigation (equal); methodology (lead); project administration (equal); resources (lead); software (lead); supervision (equal); validation (supporting); visualization (lead); writing – original draft (equal); writing – review and editing (lead). BB: Conceptualization (supporting); methodology (supporting); supervision (supporting); writing – review and editing (supporting). EA: Formal analysis (supporting); resources (supporting); visualization (supporting); writing – review and editing (supporting). FD: Conceptualization (supporting); data curation (supporting); investigation (supporting); resources (supporting); software ( supporting ) ; visualization (supporting); writing – original draft (supporting); writing – review and editing (lead). FSD: Formal analysis (supporting); investigation (supporting); supervision (supporting). EÜ: Resources (supporting); visualization (supporting). MMİ: Data curation (supporting); software (supporting); supervision (supporting). EK: Formal analysis (supporting); investigation (supporting); software (supporting). AŞ: Formal analysis (supporting); investigation (supporting); methodology (supporting); validation (supporting); writing – original draft (supporting). MK: Validation (supporting). GBB: Formal analysis (supporting). FNK: Data curation (supporting); resources (supporting); validation (supporting); visualization (supporting); writing – original draft (supporting). MOS: Data curation (supporting); resources (supporting); visualization (supporting). VA: Resources (supporting). HA: Conceptualization (supporting); investigation (supporting); methodology (supporting). Bİ: Validation (supporting). MEÇ: Resources (supporting). DD: Resources (supporting). RÇ: Data curation (supporting); resources (supporting); writing – original draft (supporting). İS: Validation (supporting). ENA: Data curation (supporting). ACT: Formal analysis (supporting). YHT: Resources (supporting). Funding acquisition: None.

None Declared.

None.

References

1. Maia IW, Besen BA, Silva LO, von Hellmann R, Hajjar LA, Sandefur BJ, et al. Peri intubation adverse events and clinical outcomes in emergency department patients: The BARCO study. Crit Care 2025;29:155.
2. Yang TH, Shao SC, Lee YC, Hsiao CH, Yen CC. Risk factors for peri intubation cardiac arrest: A systematic review and meta analysis. Biomed J 2024;47:100656.
3. Weingart SD, Levitan RM. Preoxygenation and prevention of desaturation during emergency airway management. Ann Emerg Med 2012;59:165 75.e1.
4. Pitre T, Liu W, Zeraatkar D, Casey JD, Dionne JC, Gibbs KW, et al. Preoxygenation strategies for intubation of patients who are critically ill: A systematic review and network meta analysis of randomised trials. Lancet Respir Med 2025;13:585 96.
5. GuyattGH, OxmanAD, Schünemann HJ, TugwellP, KnottnerusA. GRADE guidelines: A new series of articles in the Journal of Clinical Epidemiology. J Clin Epidemiol 2011;64:380 2.
6. Ouzzani M, Hammady H, Fedorowicz Z, Elmagarmid A. Rayyan a web and mobile app for systematic reviews. Syst Rev 2016;5:210.
7. Baillard C, Prat G, Jung B, Futier E, Lefrant JY, Vincent F, et al. Effect of preoxygenation using non invasive ventilation before intubation on subsequent organ failures in hypoxaemic patients: A randomised clinical trial. Br J Anaesth 2018;120:361 7.
8. Guitton C, Ehrmann S, Volteau C, Colin G, Maamar A, Jean Michel V, et al. Nasal high flow preoxygenation for endotracheal intubation in the critically ill patient: A randomized clinical trial. Intensive Care Med 2019;45:447 58.
9. Gibbs KW, Semler MW, Driver BE, Seitz KP, Stempek SB, Taylor C, et al. Noninvasive ventilation for preoxygenation during emergency intubation. N Engl J Med 2024;390:2165 77.
10. Baillard C, Fosse JP, Sebbane M, Chanques G, Vincent F, Courouble P, et al. Noninvasive ventilation improves preoxygenation before intubation of hypoxic patients. Am J Respir Crit Care Med 2006;174:171 7.
11. Li J, Liu B, Zhou QH, Ni HD, Liu MJ, Deng K. Pre oxygenation with high flow oxygen through the nasopharyngeal airway compared to facemask on carbon dioxide clearance in emergency adults: A prospective randomized non blinded clinical trial. Eur J Trauma Emerg Surg 2024;50:1051 61.
12. Luo D, Wan X, Liu J, Tong T. Optimally estimating the sample mean from the sample size, median, mid range, and/or mid quartile range. Stat Methods Med Res 2018;27:1785 805.
13. Chua MT, Ng WM, Lu Q, Low MJ, Punyadasa A, Cove ME, et al. Pre and apnoeic high flow oxygenation for rapid sequence intubation in the emergency department (the Pre AeRATE trial): A multicentre randomised controlled trial. Ann Acad Med Singap 2022;51:149 60.
14. Frat JP, Ricard JD, Quenot JP, Pichon N, Demoule A, Forel JM, et al. Non invasive ventilation versus high flow nasal cannula oxygen therapy with apnoeic oxygenation for preoxygenation before intubation of patients with acute hypoxaemic respiratory failure: A randomised, multicentre, open label trial. Lancet Respir Med 2019;7:303 12.
15. Karlupia D, Garg K, Jain R, Grewal A. Transnasal humidified rapid insufflation ventilatory exchange versus conventional facemask breathing for preoxygenation during rapid sequence induction. Cureus 2023;15:e43063.
16. Tarigonda S, Nagaiah SK, Manem A, Krishnamurthy D. Comparison of two techniques of peri intubation oxygenation to minimize the degree of desaturation in patients with hypoxemic respiratory failure in the intensive care unit. Med J D Y Patil Vidyapeeth 2023;16 Suppl 2:S222 7.
17. Jaber S, Amraoui J, Lefrant JY, Arich C, Cohendy R, Landreau L, et al. Clinical practice and risk factors for immediate complications of endotracheal intubation in the intensive care unit: Aprospective, multiple center study. Crit Care Med 2006;34:2355 61.
18. Simpson GD, Ross MJ, McKeown DW, Ray DC. Tracheal intubation in the critically ill: A multi centre national study of practice and complications. Br J Anaesth 2012;108:792 9.
19. De Jong A, Molinari N, Terzi N, Mongardon N, Arnal JM, Guitton C, et al. Early identification of patients at risk for difficult intubation in the intensive care unit: Development and validation of the MACOCHA score in a multicenter cohort study. Am J Respir Crit Care Med 2013;187:832 9.
20. Mort TC. Preoxygenation in critically ill patients requiring emergency tracheal intubation. Crit Care Med 2005;33:2672 5.
21. Semler MW, Janz DR, Lentz RJ, Matthews DT, Norman BC, Assad TR, et al. Randomized trial of apneic oxygenation during endotracheal intubation of the critically ill. Am J Respir Crit Care Med 2016;193:273 80.
22. Caputo N, Azan B, Domingues R, Donner L, Fenig M, Fields D, et al. Emergency department use of apneic oxygenation versus usual care during rapid sequence intubation: A randomized controlled trial (the ENDAO trial). Acad Emerg Med 2017;24:1387 94.
23. Shahul Hameed IZ, Hazra D, Ganesan P, Prabhakar AK. Does apneic oxygenation with nasopharyngeal cannula during intubation improve the oxygenation in patients with acute hypoxemic respiratory failure compared to the standard bag valve mask preoxygenation? An open labeled randomized control trial. Turk J Emerg Med 2024;24:33 40.
24. Vourc’h M, Asfar P, Volteau C, Bachoumas K, Clavieras N, Egreteau PY, et al. High flow nasal cannula oxygen during endotracheal intubation in hypoxemic patients: A randomized controlled clinical trial. Intensive Care Med 2015;41:1538 48.
25. Jaber S, Monnin M, Girard M, Conseil M, Cisse M, Carr J, et al. Apnoeic oxygenation via high flow nasal cannula oxygen combined with non invasive ventilation preoxygenation for intubation in hypoxaemic patients in the intensive care unit: The single centre, blinded, randomised controlled OPTINIV trial. Intensive Care Med 2016;42:1877 87.
26. Simon M, Wachs C, Braune S, de Heer G, Frings D, Kluge S. High flow nasal cannula versus bag valve mask for preoxygenation before intubation in subjects with hypoxemic respiratory failure. Respir Care 2016;61:1160 7.
27. Cırıl MF, Akarca M, Unal Akoglu E, Cimilli Ozturk T, Onur Ö. High flow nasal cannula versus bag valve mask for preoxygenation during rapid sequence intubation in the emergency department: A single center, prospective, randomized controlled trial. Prehosp Disaster Med 2024;39:45 51.
28. Mir F, Patel A, Iqbal R, Cecconi M, Nouraei SA. A randomised controlled trial comparing transnasal humidified rapid insufflation ventilatory exchange (THRIVE) pre oxygenation with facemask pre oxygenation in patients undergoing rapid sequence induction of anaesthesia. Anaesthesia 2017;72:439 43.
29. Lodenius Å, Piehl J, Östlund A, Ullman J, Jonsson Fagerlund M. Transnasal humidified rapid insufflation ventilatory exchange (THRIVE) versus facemask breathing pre oxygenation for rapid sequence induction in adults: A prospective randomised non blinded clinical trial. Anaesthesia 2018;73:564 71.
30. Preya R, Ravishankar M, Sripriya R. Effectiveness of Face mask only oxygenation and apnoeic oxygenation in addition to face mask in sustaining PaO (2) during rapid sequence induction – A randomized control trial. J Anaesthesiol Clin Pharmacol 2023;39:366 71.
31. Bawa C, Raina J, Dureja M, Singh A, Yadav N, Kumar A. Intubation performance with stylet and preloaded bougie for rapid sequence intubation in patients undergoing general anaesthesia: A randomized clinical trial. J Clin Diagn Res 2022;16:UC15 9.
32. Driver BE, Semler MW, SelfWH, Ginde AA, Trent SA, Gandotra S, et al. Effect of use of a bougie versus endotracheal tube with stylet on successful intubation on the first attempt among critically ill patients undergoing tracheal intubation: A randomized clinical trial. JAMA 2021;326:2488 97.
33. Driver BE, Prekker ME, Klein LR, Reardon RF, Miner JR, Fagerstrom ET, et al. Effect of use of a bougie versus endotracheal tube and stylet on first attempt intubation success among patients with difficult airways undergoing emergency intubation: A randomized clinical trial. JAMA 2018;319:2179 89.
34. Dutta A, Sethi N, Choudhary P, Gupta M, Malhotra S, Panday BC, et al. The impact of tracheal tube introducer guided intubation in anticipated non difficult airway on postoperative sore throat: A randomized controlled trial. Minerva Anestesiol 2020;86:913 21.
35. Gataure PS, Vaughan RS, Latto IP. Simulated difficult intubation. Comparison of the gum elastic bougie and the stylet. Anaesthesia 1996;51:935 8.
36. Ghai A, Bharti N, Jain M, Wadhera S, Singh AK, Wadhera R. Endotracheal intubation with laryngeal mirror in simulated difficult direct laryngoscopy: Comparison of gum elastic bougie versus styleted endotracheal tube. Indian J Otolaryngol Head Neck Surg 2022;74:5448 53.
37. Heegaard WG, Black C, Pasquerella C, Miner J. Use of the endotracheal tube introducer as an adjunct for oral tracheal intubation in the prehospital setting. Air Med J 2003;22:28 31.
38. Khan R, Khan F, Azam M. Comparison of the stylet and the gum elastic bougie in tracheal intubation in a simulated difficult airway. Anaesth Pain Intensive Care 2014;18:256 9.
39. Noguchi T, Koga K, Shiga Y, Shigematsu A. The gum elastic bougie eases tracheal intubation while applying cricoid pressure compared to a stylet. Can J Anaesth 2003;50:712 7.
40. Nolan JP, Wilson ME. Orotracheal intubation in patients with potential cervical spine injuries. An indication for the gum elastic bougie. Anaesthesia 1993;48:630 3.
41. Sut EY, Gunal S, Yazar MA, Dikmen B. Comparison of effectiveness of intubation by way of “gum elastic bougie” and “intubating laryngeal mask airway” in endotracheal intubation of patients with simulated cervical trauma. Rev Bras Anestesiol 2017;67:238 45.
42. Russotto V, Myatra SN, Laffey JG, Tassistro E, Antolini L, Bauer P, et al. Intubation practices and adverse peri intubation events in critically ill patients from 29 countries. JAMA 2021;325:1164 72.
43. Heffner AC, Swords D, Kline JA, Jones AE. The frequency and significance of postintubation hypotension during emergency airway management. J Crit Care 2012;27:417.e9 13.
44. Weingart S. Push dose pressors for immediate blood pressure control. Clin Exp Emerg Med 2015;2:131 2.
45. McPherson KL, Kovacic Scherrer NL, Hays WB, Greco AR, Garavaglia JM. A review of push dose vasopressors in the peri operative and critical care setting. JPharm Pract 2023;36:925 32.
46. da Silveira F, de Oliveira LH, Nedel W, Lisboa TC. Effectiveness of prophylactic push dose vasopressors for preventing arterial hypotension during elective orotracheal intubation: A systematic review and meta analysis. J Crit Care 2025;91:155275.
47. Panchal AR, Satyanarayan A, Bahadir JD, Hays D, Mosier J. Efficacy of bolus dose phenylephrine for peri intubation hypotension. J Emerg Med 2015;49:488 94.
48. Schwartz MB, Ferreira JA, Aaronson PM. The impact of push dose phenylephrine use on subsequent preload expansion in the ED setting. Am J Emerg Med 2016;34:2419 22.
49. Swenson K, Rankin S, Daconti L, Villarreal T, Langsjoen J, Braude D. Safety of bolus dose phenylephrine for hypotensive emergency department patients. Am J Emerg Med 2018;36:1802 6.
50. Rotando A, Picard L, Delibert S, Chase K, Jones CM, Acquisto NM. Push dose pressors: Experience in critically ill patients outside of the operating room. Am J Emerg Med 2019;37:494 8.
51. Davis DP, Olvera D, Selde W, Wilmas J, Stuhlmiller D. Bolus vasopressor use for air medical rapid sequence intubation: The vasopressor intravenous push to enhance resuscitation trial. Air Med J 2023;42:36 41.
52. FuchitaM, Pattee J, RussellDW, DriverBE, PrekkerME, Barnes CR, et al. Prophylactic administration of vasopressors prior to emergency intubation in critically ill patients: Asecondary analysis of two multicenter clinical trials. Crit Care Explor 2023;5:e0946.
53. Schmitt CJ, Mattson AE, Brown CS, Mara KC, Cabrera D, Sandefur BJ, et al. The incidence of cardiovascular instability in patients receiving various vasopressor strategies for peri intubation hypotension. Am J Emerg Med 2023;65:104 8.
54. Singer S, Pope H, Fuller BM, Gibson G. The safety and efficacy of push dose vasopressors in critically ill adults. Am J Emerg Med 2022;61:137 42.
55. Nam E, Fitter S, Moussavi K. Comparison of push dose phenylephrine and epinephrine in the emergency department. Am J Emerg Med 2022;52:43 9.
56. Nawrocki PS, Poremba M, Lawner BJ. Push dose epinephrine use in the management of hypotension during critical care transport. Prehosp Emerg Care 2020;24:188 95.
57. Chang LC, Raty SR, Ortiz J, Bailard NS, Mathew SJ. The emerging use of ketamine for anesthesia and sedation in traumatic brain injuries. CNS Neurosci Ther 2013;19:390 5.
58. Shapiro HM, Wyte SR, Harris AB. Ketamine anaesthesia in patients with intracranial pathology. Br J Anaesth 1972;44:1200 4.
59. Gibbs JM. The effect of intravenous ketamine on cerebrospinal fluid pressure. Br J Anaesth 1972;44:1298 302.
60. Zeiler FA, Teitelbaum J, West M, Gillman LM. The ketamine effect on ICP in traumatic brain injury. Neurocrit Care 2014;21:163 73.
61. Schmittner MD, Vajkoczy SL, Horn P, Bertsch T, Quintel M, Vajkoczy P, et al. Effects of fentanyl and S(+) ketamine on cerebral hemodynamics, gastrointestinal motility, and need of vasopressors in patients with intracranial pathologies: A pilot study. J Neurosurg Anesthesiol 2007;19:257 62.
62. Bourgoin A, Albanèse J, Léone M, Sampol Manos E, Viviand X, Martin C. Effects of sufentanil or ketamine administered in target controlled infusion on the cerebral hemodynamics of severely brain injured patients. Crit Care Med 2005;33:1109 13.
63. Bourgoin A, Albanèse J, Wereszczynski N, Charbit M, Vialet R, Martin C. Safety of sedation with ketamine in severe head injury patients: Comparison with sufentanil. Crit Care Med 2003;31:711 7.
64. Kolenda H, Gremmelt A, Rading S, Braun U, Markakis E. Ketamine for analgosedative therapy in intensive care treatment of head injured patients. Acta Neurochir(Wien) 1996;138:1193 9.
65. Burman S, Chouhan RS, Kumar N, Mahajan C. Effect of ketamine analgosedation on neurological outcome in patients with severe traumatic brain injury: A randomized controlled pilot study. Neurocrit Care 2026;44:9 17.
66. Michalczyk K, Sullivan JE, Berkenbosch JW. Pretreatment with midazolam blunts the rise in intracranial pressure associated with ketamine sedation for lumbar puncture in children. Pediatr Crit Care Med 2013;14:e149 55.
67. Ben Yehuda Y, Watemberg N. Ketamine increases opening cerebrospinal pressure in children undergoing lumbar puncture. J Child Neurol 2006;21:441 3.
68. Lyon RM, Perkins ZB, Chatterjee D, Lockey DJ, Russell MQ, Kent, Surrey and Sussex Air Ambulance Trust. Significant modification of traditional rapid sequence induction improves safety and effectiveness of pre hospital trauma anaesthesia. Crit Care 2015;19:134.
69. Cornelius BG, Webb E, Cornelius A, Smith KW, Ristic S, Jain J, et al. Effect of sedative agent selection on morbidity, mortality and length of stay in patients with increase in intracranial pressure. World J Emerg Med 2018;9:256 61. [doi: 10.5847/wjem.j. 1920 8642.2018.04.003].
70. Mudri M, Williams A, Priestap F, Davidson J, Merritt N. Comparison of drugs used for intubation of pediatric trauma patients. J Pediatr Surg 2020;55:926 9.
71. Mazandi VM, Lang SS, Rahman RK, Nishisaki A, Beaulieu F, Zhang B, et al. Co administration of ketamine in pediatric patients with neurologic conditions at risk for intracranial hypertension. Neurocrit Care 2023;38:242 53.
72. Mansvelder FJ, Bossers SM, Loer SA, Bloemers FW, Van Lieshout EM, Den Hartog D, et al. Etomidate versus ketamine as prehospital induction agent in patients with suspected severe traumatic brain injury. Anesthesiology 2024;140:742 51.
73. Loi MV, Lee JH, Huh JW, Mallory P, Napolitano N, Shults J, et al. Ketamine use in the intubation of critically ill children with neurological indications: A multicenter retrospective analysis. Neurocrit Care 2024;40:205 14.
74. Fouche PF, Meadley B, St Clair T, Winnall A, Jennings PA, Bernard S, et al. The association of ketamine induction with blood pressure changes in paramedic rapid sequence intubation of out of hospital traumatic brain injury. Acad Emerg Med 2021;28:1134 41.
75. Bar Joseph G, Guilburd Y, Tamir A, Guilburd JN. Effectiveness of ketamine in decreasing intracranial pressure in children with intracranial hypertension. J Neurosurg Pediatr 2009;4:40 6.
76. Caricato A, Tersali A, Pitoni S, De Waure C, Sandroni C, Bocci MG, et al. Racemic ketamine in adult head injury patients: Use in endotracheal suctioning. Crit Care 2013;17:R267.
77. Dengler BA, Karam O, Barthol CA, Chance A, Snider LE, Mundy CM, et al. Ketamine boluses are associated with a reduction in intracranial pressure and an increase in cerebral perfusion pressure: A retrospective observational study of patients with severe traumatic brain injury. Crit Care Res Pract 2022;2022:3834165.
78. Laws JC, Vance EH, Betters KA, Anderson JJ, Fleishman S, Bonfield CM, et al. Acute effects of ketamine on intracranial pressure in children with severe traumatic brain injury. Crit Care Med 2023;51:563 72.

This clinical policy has been prepared by the RC of the Emergency Medicine Association of Türkiye (EMAT) for emergency physicians. We would like to express our sincere gratitude to all EMAT Board members, RC members, and the Airway Working Group for their support, valuable contributions, and dedicated efforts throughout the development of this clinical policy.