Emergency department pain management in special populations

Katherine Vlasica1, Amanda Hall1, Mohammad Anzal Rehman2, George Notas3, Christina Shenvi4, Sergey Motov5

1Department of Emergency Medicine, St. Joseph’s Health, Paterson, NJ, USA
2Department of Emergency Medicine, Mediclinic City Hospital, Dubai, UAE
3Department of Emergency Medicine, University Hospital of Heraklion, Crete, Greece
4Department of Emergency Medicine, University North Carolina Hospitals, Chapel Hill, NC, USA
5Department of Emergency Medicine, Maimonides Medical Center, Brooklyn, NY, USA

Keywords: Analgesia, emergency department, pain management

Abstract

Pain is a leading cause of emergency department (ED) visits globally, yet certain patient populations experience persistent disparities in their pain management due to physiological complexities, comorbidities, and gaps in evidence based guidelines. This clinical review focuses on individualized, evidence based approaches to ED pain management in four vulnerable groups: pregnant and breastfeeding patients, patients with sickle cell disease, geriatric populations, and patients with cancer pain and requiring palliative care. The practical recommendations presented in this review for optimal ED pain management in these special populations call for timely, effective, and multimodal analgesia; prioritization of nonpharmacologic and pain syndrome targeted techniques; awareness of drug disease and drug drug interactions; interdisciplinary coordination; and education to mitigate ED clinicians’ biases. This review emphasizes the importance of tailoring pain strategies to population specific needs to improve outcomes, reduce harm, and advance equity in emergency care delivery.

Introduction

Pain is a common presenting complaint in emergency departments (EDs) worldwide, with up to 78% of ED visits involving pain as a primary or secondary symptom.[1,2] Despite advances in ED pain management, certain patient populations present unique challenges requiring individualized, pain syndrome specific approach to achieve optimal analgesia while minimizing adverse outcomes. Pregnant women, people with sickle cell disease (SCD), geriatric patients, and patients with cancer pain or palliative care represent vulnerable populations whose pain management needs often diverge significantly from standard protocols, necessitating evidence based, population specific interventions.[3 6]

The management of pain in these special populations is complicated due to altered pharmacokinetics, comorbidities, physiological vulnerabilities, refractoriness to conventional therapeutic approaches, and concerns about medication safety that frequently translate into inadequate pain control in the ED. This focused clinical review aims to provide emergency physicians with evidence based approaches to pain management in these challenging populations.

Pain Management of Pregnant and Breastfeeding Patients in the Emergency Department

Acute pain is common in pregnancy, with analgesics being the third most prescribed medication class after antiemetics and antibiotics.[7] Managing pain in pregnancy and breastfeeding requires a tailored and multifaceted approach that balances pharmacologic and nonpharmacologic options with fetal safety risks. However, evidence based guidelines remain limited due to the historical exclusion of pregnant women from clinical trials, leaving clinicians to navigate treatment with incomplete data. Physiological changes in pregnancy(altered drug metabolism, hepatic and renal clearance, volume distribution changes, and placental transfer) further complicate drug pharmacokinetics and fetal exposure risks.[8]

ED clinicians must assess the risks of untreated illness and potential adverse effects of pharmacotherapy on pregnancy and breastfeeding and unfavorable perinatal and infant outcomes such as miscarriage, major congenital disabilities, preterm birth, stillbirth, neonatal adaptation signs, and behavioral and developmental effects.[7,9] Table 1 lists commonly used analgesics (dosing and routes) in pregnant and breastfeeding patients.

Table 1. Commonly used analgesics in pregnancy and lactation


Table 1. Contd...

Commonly used analgesics in pregnancy and breastfeeding

Acetaminophen (Paracetamol, APAP)

Acetaminophen is used in 40%–70% of pregnancies and is the only pain medication considered safe during pregnancy and compatible with breastfeeding.[7,10] Its use has no clear evidence linking it to fetal developmental issues.[7,10,11] Oral, intravenous (IV), and rectal formulations are available with a maximum of 4000 mg per day with IV single infusion of 1000 mg not exceeding 15 min. A large population based study of 185,909 children found no significant link to autism, ADHD, or intellectual disabilities.[12] A systematic review and meta analysis also found no association with preterm birth or low birth weight, though data on dosage and frequency were limited.[13,14]

Nonsteroidal anti inflammatory drugs

NSAIDs, including their parenteral, oral, and topical forms, are generally considered safe in pregnant and lactating women and are commonly used for musculoskeletal(MSK) pain, headaches, and renal colic.[7,15] However, their use during pregnancy requires caution due to potential embryo fetal risks based on specific NSAID, gestational timing, and duration of use.[7,15] NSAIDs are contraindicated in the third trimester due to risks of premature ductus arteriosus closure and uteroplacental vasoconstriction.[16]

Beyond 20 weeks, NSAID use has been linked to fetal nephrotoxicity and oligohydramnios, prompting FDA recommendations to minimize use after 20 weeks and avoid it entirely after 30 weeks.[17] NSAIDs can be used cautiously in the first and second trimesters with the lowest effective dose and shortest course when benefits outweigh the risks, as courses longer than 10 days may adversely affect fetal health.[18]

Opioids

Opioids are widely used for pain management during pregnancy via IV, oral (PO), sublingual (SL), and intranasal (IN) routes. Frequent titration and the use of the lowest effective dose for the shortest duration are recommended to minimize complications.[19,20] Opioids increase the risk of Neonatal Opioid Withdrawal Syndrome (NOWS) with stronger opioid agonists (e.g., oxycodone, methadone, hydromorphone, and morphine) posing a higher NOWS risk.[20,21]

Pregnant women with opioid use disorder (OUD) face higher risks of inadequate prenatal care, fetal growth restriction, preterm labor, and NOWS.[20,21] Methadone or buprenorphine should be initiated promptly, as both improve maternal and fetal outcomes. Buprenorphine has been associated with reduced neonatal withdrawal and increased birth weight, making it the preferred option for OUD treatment during pregnancy.[20]

Despite the relative infant dose of opioids in breast milk being in the range of 1%–5% of the mother’s therapeutic dose, there are significant risks associated with continued breastfeeding while on opioids.[21] The around the clock use of opioids by the mother during breastfeeding should be limited to 2–3 days,[22] Tramadol and codeine should be avoided due to the risk of life threatening respiratory depression in infants of mothers with the ultra rapid CYP2D6 metabolizer phenotype.[23]

Steroids

Corticosteroids administered as a short course orally, topically, or intravenously are generally considered safe for treating radicular back pain, joint pain, and inflammatory pain during pregnancy.[19] Prolonged or chronic use has been linked to cataracts, fetal growth restriction, both maternal and fetal immunosuppression, and adrenal insufficiency.[24] Rheumatological guidelines recommend the use of nonfluorinated glucocorticoids, such as prednisone and prednisolone, as they do not cross the placenta.[8,25] Maternal exposure to topical corticosteroids without exceeding the recommended dose revealed no causal association with fetal orofacial clefts, preterm delivery, or low Apgar score.[26]

Magnesium

Magnesium is commonly used in obstetrics and has been well tolerated by both the mother and baby in the treatment of acute and chronic painful syndromes.[16,27,28] Several randomized controlled trials (RCTs) have shown that magnesium supplementation can help relieve muscle cramps, improve general comfort, and promote better sleep during pregnancy.[29] For migraine headaches, magnesium is often used in combination with other medications.[30]

Anticonvulsants (gabapentin and pregabalin)

Gabapentin and pregabalin are commonly used for postherpetic neuralgia, diabetic neuropathy, and radicular back pain in pregnant patients and are generally safe in breastfeeding. A large population based study of 4642 pregnancies with early gabapentin exposure did not demonstrate an association with major congenital malformations. However, maternal gabapentin use in late pregnancy was associated with a 20%–30% increased risk of preterm birth, a 30%–40% increased risk of small for gestational age infants, and a 35% increased likelihood of neonatal intensive care unit admission.[31] Research related to pregabalin in pregnancy is even more sparse, suggesting no teratogenicity, but its unpredictable absorption may cause maternal sedation.[32]

Local anesthetics and targeted analgesia

Targeted analgesic techniques such as topical, local, and regional anesthesia offer rapid pain relief with minimal systemic effects to pregnant and lactating patients.[16,17,19] In addition, existing research of large observational studies demonstrates no evidence of teratogenicity of local anesthetic administered topically, locally, or regionally.[33 35] Very small amounts of local anesthetics are secreted into the breast milk of lactating mothers, with ropivacaine having the lowest transmission rate compared to lidocaine and bupivacaine.[15]

Antidopaminergics

Antidopaminergics (metoclopramide, prochlorperazine, droperidol, and haloperidol) are frequently used for the management of intractable nausea/vomiting, primary headache, and intractable abdominal pain in the ED. While generally safe in pregnancy and breastfeeding, the use of metoclopramide might be associated with maternal extrapyramidal symptoms. The use of phenothiazines rarely leads to the development of cleft palate, skeletal, limb, and cardiac abnormalities, as well as neonatal respiratory depression during pregnancy. The administration of droperidol or haloperidol is often avoided due to concerns about maternal prolonged QTc.[36]

Muscle relaxants

The use of central muscle relaxants such as baclofen, methocarbamol, chlorzoxazone, cyclobenzaprine, tizanidine, and thiocolchicoside should be generally avoided in pregnant patients as numerous animal studies demonstrated teratogenicity of such medications and human data is severely limited.[37,38]

Nitrous oxide

The use of nitrous oxide during pregnancy, particularly for short term procedures and labor pain management, appears to be safe with no significant adverse effects on the fetus. However, long term exposure to high concentrations of nitrous oxide, such as in occupational or recreational settings, may negatively impact fertility and fetal outcomes. Additionally, there are concerns regarding its use in the first trimester, where the inactivation of Vitamin B12 disrupts the folate metabolism.[39] Further research is needed to fully understand the implications of nitrous oxide use, especially in preterm pregnancies.[39 43]

Ketamine

Ketamine is frequently used in the ED for procedural sedation and analgesia, intubation, and pain management. Ketamine readily crosses the placenta and preferentially distributes in neuronal tissue, raising concerns about its neurotoxic effects in the developing brain.[44 46] Additionally, animal models of prenatal exposure to ketamine demonstrated long term behavioral and cognitive deficits, including hyperactivity, disinhibition, social withdrawal, anxiety, depression, and aggression in adulthood.[47,48] While direct human evidence is lacking, these data raise significant concerns about potential neurotoxic effects of ketamine on a developing fetus and its use should be generally avoided in pregnancy.[49]

Complementary and alternative therapies

Exercise and physical therapy have been associated with reduced pain intensity, decreased disability, and improved quality of life in pregnancy related MSK and back pain.[20,50,51] Osteopathic manipulative treatment was shown to decrease low back pain intensity and improve functional status in pregnancy.[50,51] Transcutaneous electrical nerve stimulation has been found to be safe in all trimesters, demonstrating efficacy in lumbar pain and a small but measurable benefit for labor pain.[20,50 53] Additionally, pelvic belts have been shown to be quite effective in the treatment of symphyseal and pelvic girdle pain, outperforming exercise therapy alone.[20] Acupuncture has been investigated for pregnancy related back pain and labor analgesia, with some studies demonstrating significant pain relief, though methodological limitations remain.[54,55]

Breastfeeding

Breastfeeding all drugs under 1000 kDa transfer into breast milk. A quantitative estimate of how much medication is transferred to the nursing infant is expressed as a relative infant dose (RID). For most drugs, a RID of 10% or less is considered relatively safe; caution is required for drugs excreted in dosages of 10%–25% of the maternal dosage; and those few drugs excreted in dosages over 25% of the maternal dosage are considered unacceptable.[56]

Take home pearls

• Prescribe at the lowest effective dose, quantity, and duration of treatment to minimize in utero exposure to medications

• Prioritize topicals and nonpharmacological therapies over systemic treatments

• Use targeted analgesia whenever possible

• Collaborate with patients to establish treatment goals.

Management of Pain in Patients with Sickle Cell Disease in the Emergency Department

SCD is an autosomal recessive disorder characterized by disrupted morphology (sickling) that affects close to 8 million people globally and results in painful crises, hemolytic anemia, splenic sequestration, infections, and stroke.[57] The most common presenting symptom for patients in the ED is pain associated with vaso occlusive crisis (VOC) due to organ ischemia and neurogenic inflammation.[58] National estimates in the United States (U. S.) found that nearly 75% of all SCD patients presenting to the ED had a primary complaint of pain,[59] with a significant increase in utilization of opioid based analgesia.[60]

The best practice guidelines by the American Society of Hematology (ASH) and the American College of Emergency Physicians recommend assessing all patients presenting with acute VOC to the ED as high risk, administering appropriate analgesia within 1 h of arrival with pain reassessment every 30–60 min, and individualizing the plans of care for each patient based on their history of analgesic use and effective dosage and route for pain relief in the past. The goal of analgesia in VOC is to provide appropriate relief for patient discomfort in a safe and effective manner while evaluating patients for underlying complications of SCD.[61] Table 2 lists common therapeutic modalities with their dosing and routes for pain control in patients with SCD.

Table 2. Summary of analgesic options in the treatment of acute pain in vaso‑occlusive crisis in sickle‑cell disease patients

Therapeutic modalities

Paracetamol (acetaminophen, APAP)

Paracetamol’s mechanism of action for pain reduction seems to primarily involve its central inhibition of cyclooxygenase (COX), without a significant anti inflammatory effect. The use of IV acetaminophen (with its debatable analgesic superiority over oral form[62] in combination with opioids for VOC has been associated with pain reduction and opioid sparing in one trial,[63] and an absence of such effects in another.[64] As a single analgesic, IV acetaminophen was found to be superior to IV diclofenac for skeletal VOC in pediatric patients.[65]

To date, no published RCTs have examined IV APAP’s clinical efficacy, either as a single agent or as an adjunct to opioids for VOC treatment in adults. Recommended dosing is 10–15 mg/kg per dose in children (500–1000 mg per dose in adults), with a maximum dose of 75 mg/kg/day in children (4 g in adults). Adverse effects include nausea and vomiting, with hepatic insufficiency being one of the major contraindications and lack of titratability as a major limitation.

Nonsteroidal antiinflammatory drugs

Nonsteroidal antiinflammatory drugs (NSAIDs) act by reducing both pain and inflammation through the inhibition of COX enzymes, thereby decreasing prostaglandin production. As a part of multimodal analgesia, ibuprofen, ketorolac, diclofenac, ketoprofen, and dexketoprofen were found to be beneficial in reducing pain and overall opioid consumption.[66] Despite demonstrated equianalgesia to morphine in some studies,[67,68] the Cochrane database systematic review found the evidence of insufficient quantity and quality to reliably confirm significant efficacy of NSAIDs for acute pain in sickle cell patients.[69] NSAIDs should be administered in the safest doses, not exceeding accepted analgesic ceilings, and for the shortest period to avoid complications, such as renal dysfunction and peptic ulcer disease.[70]

Opioids

Opioids remain the cornerstone of management of pain in VOC. Commonly used mu receptor agonists (morphine, hydromorphone, and fentanyl) decrease afferent nociceptive signals, thereby reducing pain sensation. Parenteral formulations must be titrated to optimal analgesic effect, and only immediate release and short acting opioids should be used in the ED for VOC treatment. Opioid administration should target achievement of a “therapeutic window,’ where optimal analgesia is achieved with the least amount of side effects, which could include nausea/vomiting, itching, dizziness, somnolence, and even respiratory depression. The factors affecting this “therapeutic window” in patients with VOC include renal and hepatic function, drug metabolism, prior pain events, and amount and duration of opioid use in the past.[71,72]

Numerous clinical trials support the use of IN administration of hydromorphone and fentanyl for sickle cell patients in the ED, demonstrating similar analgesic efficacy to their parenteral counterparts. Similarly, SL administration of fentanyl, sufentanil, and buprenorphine resulted in significant pain relief of acute pain of VOC.[73] The subcutaneous route is a suboptimal choice for such patients due to the delay in the onset of analgesia, and the intramuscular route should be avoided due to severe pain on injection, unpredictable absorption, and the development of myofibrosis.[73,74]

Once optimal analgesia is achieved, those patients admitted for subsequent pain management could benefit from patient controlled analgesia (PCA) infusions or intermittent boluses. The use of PCA in the ED may also have a positive impact on patient satisfaction and reduced need for additional analgesics, provided adequate training and experience with this modality is maintained amongst ED providers.[75]

Opioid tolerance, which is associated with a reduction in analgesic effect following repeated or prolonged opioid use, and opioid induced hyperalgesia (OIH) a paradoxical nociceptive sensitization leading to a hyper response to acute noxious stimuli in the setting of opioid therapy are frequently present in sickle cell patients.[76] Given the considerable variability in dosage and response for patients receiving opioids, the approach to optimal analgesia, including choice of drug, dose, and route, should be individualized based on each patient’s severity of pain and level of reduction following opioid administration.[72]

Finally, the metabolism of tramadol and codeine is dependent on the hepatic CYP2D6 enzyme, which affects the amount of available active metabolite due to gene polymorphism in sickle cell patients, thus warranting avoidance of these opioids in these patients.[77]

Adjunctive therapies

Ketamine is a noncompetitive antagonist of N-methylD-aspartate and plays a role in the reduction of pain through central sensitization. Two RCTs demonstrated similar analgesic efficacy of sub-dissociative dose ketamine to opioid-based therapy and opioid sparing effect, illustrating its potential as an adjunct in pain management for VOC.[78,79] Continuous infusions of ketamine in sub dissociative doses coupled with opioids are recommended for sickle cell patients in order to reduce dysphoria, nausea, and vomiting.[66,80]

Systemic IV administration of lidocaine, an amide local anesthetic, has been found to reduce pain and provide opioid sparing in patients with VOC. However, the data is based on retrospective case series and reports showing a variability in outcome measures and dosing. In general, both ketamine and lidocaine, while limited by current evidence, still hold potential benefits as adjuncts to opioid medication, potentially reducing the amount of opioids used to effectively manage acute pain in SCD patients.[81 83] Ultrasound guided regional analgesia targeting specific regions of acute pain in SCD patients with the potential to reduce pain warrants a future investigation for use in VOC in the ED.[84]

Nonpharmacologic options

A review of nonpharmacologic options for pain relief in sickle cell patients, including distraction therapy, cognitive–behavioral therapy, hypnosis, biofeedback, and massage, demonstrated significant reduction in pain and anxiety and improvements in patients’ satisfaction.[85] While underutilized in the ED, their inclusion as part of a multimodal analgesia regimen warrants further investigation. In addition, the involvement of a multidisciplinary team will enable optimal management of social, neuropsychiatric, surgical, and pain related outcomes.[86]

Pitfalls in emergency department pain management

Frequent use of high dosages of opioids in patients with SCD is frequently met with negative provider attitude and bias as well as fear of dependence and/ or addiction, leading to delayed and ineffective pain management.[87] Contrary to popular belief, the prevalence of opioid dependence and addiction in sickle cell disease patients is approximately 0.5%–8%.[88] Improved education about disease pathology and guideline based management may reduce negative provider attitudes and stigmas and improve strategies to enhance patient safety, timely administration of appropriate pain relief, and optimization of subsequent care for SCD patients.[89,90]

Take home pearls

• ED clinicians should attempt to create and utilize patient specific pain management pathways that improve pain management and throughput in the ED

• ED clinicians should use opioids in a safe and effective manner by frequent titration and balancing pain relief and adverse effects

• ED clinicians should utilize nonopioid analgesics and adjuncts in a judicious and effective manner for the control of acute pain

• ED clinicians should collaborate with an interdisciplinary team to ensure effective pain management in the ED and continuation of care upon discharge from the ED.

Pain Management in Cancer/Palliative Care Patients in the Emergency Department

ED’s visits of cancer patients for breakthrough pain, inadequate baseline analgesia, or serious complications are challenging due to limited initial clinical information.[91,92] Pain management varies based on cancer type, stage, treatment phase, and overall health status. Cancer and treatment related organ dysfunction alter drugs’ pharmacokinetics, complicating the analgesic response. The absence of standardized protocols and concerns about opioid overprescription can make emergency clinicians hesitant to provide optimum analgesia.[93 95] When evaluating patients with cancer pain in the ED, emergency clinicians should focus on the following elements [summarized in Table 3]: Presenting symptoms (cancer or treatment related),[91,96,97] risk stratifications (age, comorbidities),[98,99] presence of breakthrough pain,[98,99] OIH,[100] neuropathic pain as a distinct modality either from the cancer itself or as a result of chemotherapy, radiation, or surgery,[96,97,101] as well as anxiety, depression, fear, and distress.[98,101] Table 4 summarizes therapeutic approaches (dosing and routes) for the management of cancer pain.

Table 3. General approach to cancer pain in the emergency department


Table 4. Commonly used analgesics with routes and dosing regimens in the emergency department


Table 4. Contd...

Therapeutic approaches

Nonpharmacologic measures

Communication and shared decision making with patients and their families regarding pain management goals, expectations, and adverse effects are essential for timely and effective pain, stress, and anxiety control in the ED.[102] Heat and cold packs might be considered for the initial management of myalgias, arthralgias, and neuropathic pain in patients with active cancer.[103,104] Similarly, positioning and immobilization for acute pathologic fractures reduce pain exacerbation, and “position of comfort” can significantly reduce pain in patients with pleural metastases.[103,104] The efficacy of music therapy and virtual reality for breakthrough cancer pain in the ED remains largely unstudied.[103] Guided imagery, breathing exercises, and cognitive behavioral techniques might reduce pain and anxiety and should be a part of a multidisciplinary approach in the ED.[103,104]

Pharmacologic approaches [Table 4]

Opioid analgesics

Opioids are the most studied analgesics for cancer pain. Most cancer patients with breakthrough pain develop tolerance, requiring higher doses for satisfactory analgesia.[100,101,105] Morphine and fentanyl are available in parenteral, oral, IN, and rectal (morphine) forms and remain the first line option for severe cancer pain in the ED, with morphine having a longer lasting effect and fentanyl having fewer complications in patients with renal impairment.[101,105]

Hydromorphone administered in parenteral, oral, and rectal forms is equally effective for managing chronic cancer pain, but its metabolites may accumulate in patients with renal or hepatic impairment.[101,105] Although less effective than the above mentioned opioids, tramadol is frequently used for cancer pain.[106,107] Tramadol’s opioid activity is dependent on CYP2D6 metabolism, leading to significant variability in humans and a less favorable safety profile.[105 107] For patients with acute pathologic fractures, hyperalgesia, and opioid tolerance, methadone can be beneficial when other opioids are ineffective or intolerable.[108,109]

A Cochrane review demonstrated equal or even superior efficacy of transdermal buprenorphine in comparison to other opioids in cancer patients.[110,111] EPs should calculate the current daily and equivalent dosages and provide a bolus dose of an opioid equivalent to 10%–20% of the patient’s current daily dose[101,105] [Table 5]. If discharged, patients should be provided with “breakthrough doses” of opioids, preferably in a nonparenteral formulation (e.g., buccal or SL drops, tablets, or films).[101,105]

Table 5. Oral and parenteral equivalent doses of opioids and conversion ratios

Nonopioid analgesics

Paracetamol (acetaminophen) is not considered a first line therapy for cancer pain.[112,113] The Cochrane systematic review found insufficient evidence to support or refute its use either alone or in combination with codeine or dihydrocodeine in neuropathic pain.[112 114] Furthermore, there is evidence for paracetamol’s ineffectiveness in reducing the need for opioids and reducing pain in cancer patients receiving potent opioids.[113,114]

NSAIDs are found to be effective in managing cancer pain in the ED when administered alone or in combination with opioids, enhancing analgesic efficacy and reducing the need for opioids.[102,115] However, high quality evidence is lacking regarding the analgesic efficacy of NSAIDs in cancer pain.[116] It is important to consider the potential side effects and contraindications associated with NSAID use, such as gastrointestinal and renal toxicity, and to provide appropriate gastrointestinal prophylaxis when necessary.[116,117]

Sub dissociative doses of ketamine can be helpful in the treatment of opioid tolerant and refractory cancer pain.[118 120] Both intermittent and continuous IV infusions were found to reduce opioid requirements in cancer patients.[118] IN ketamine demonstrated a significant reduction in breakthrough cancer pain not controlled by opioids, with higher doses providing more significant pain relief without major side effects.[119] Oral ketamine can also be an effective adjuvant to morphine for managing refractory neuropathic cancer pain.[103,115] Several systematic reviews and guidelines showed that ketamine significantly reduces pain intensity in cancer patients and recommend considering it for refractory cancer pain.[108,120]

A single phase II study supported the efficacy and safety of IV lidocaine in refractory cancer pain.[121] Although a retrospective case series reported that cardiac monitoring is not required, it should be applied in patients with cardiac disease. If the initial bolus (1–1.5 mg/kg) is effective and well tolerated, it is followed by an infusion for prolonged symptom relief.[115,122]

Adjunctive agents

Although benzodiazepines do not have a direct analgesic effect, small boluses of midazolam (1–2 mg IV) are effective in reducing anxiety and muscle spasms.[103,115,122] Benzodiazepine use should be cautious when opioids are used concurrently due to the risk of respiratory depression.

Corticosteroids, despite limited efficacy, are commonly used as adjuvant analgesics in cancer pain management, particularly for neuropathic pain, bone metastasis, and pain associated with inflammation or edema.[123 125] Dexamethasone is preferred for most oncologic emergencies. Significant hyperglycemic effects should be anticipated in diabetic patients.

Anticonvulsants such as gabapentin and pregabalin can be helpful adjuncts for neuropathic types of cancer pain. The initiation of gabapentin or pregabalin in the ED for compression or chemotherapy induced neuropathies may be considered, although these therapeutics are not expected to provide immediate relief[126 128] and may worsen opioid induced respiratory depression.[128]

There is strong evidence from several RCT that antiemetics should be considered early for co-administration with opioids to prevent nausea/vomiting.[129,130] Ondansetron (4–8 mg IV) is regarded as the first line treatment, with metoclopramide (10 mg IV) as an alternative.[115,129,130]

Nerve blocks

Ultrasound guided nerve blocks are an excellent therapeutic modality for cancer patients who present to the ED with properly localized acute pain.[115,131,132] Numerous RCTs support their efficacy and safety in such patients, with intercostal blocks for rib metastases and femoral nerve blocks for pathologic hip fractures being commonly used in the ED.[131,132] While cryo neurolysis has been more commonly applied to conditions like rib fractures and postsurgical pain, its principles and efficacy in neuropathic pain management also make it a suitable option for cancer related pain in the emergency department.[133 135]

Common pitfalls in cancer pain management in the emergency department

Although the list of potential pitfalls in cancer pain management is vast, they can be categorized into assessment issues, treatment related issues, opioid related pitfalls, system gaps, and psychosocial and patient related factors [Table 6]. EPs commonly encounter one or more of these pitfalls when treating such patients.

Table 6. Common pitfalls in cancer pain management in the emergency department

Take home pearls

• Consider acute cancer/treatment complications and comorbidities as potential causes of pain and avoid “cancer pain bias”

• Communicate goals and expectations with patients and their families and utilize a multimodal approach of nonpharmacologic and pharmacologic treatment modalities

• Calculate opioid requirements based on home regimens and use careful titration in renal/ hepatic dysfunction. Use short acting opioids for breakthrough pain. If the patient is discharged, provide a discharge analgesic rescue plan

• Use NSAIDs (with caution), ketamine (for opioidtolerant patients), and adjuncts (anticonvulsants for neuropathic pain, antiemetics) for pain control

• Consider ultrasound guided nerve blocks

• Acknowledge anxiety, depression, stress, and distress. Exercise empathy and consider anxiolytics if appropriate

• When in doubt, consult: Do not hesitate to seek guidance from palliative care specialists and/or pain management experts.

Emergency Department Pain Management of Older Adults

Managing acute pain in elderly patients (>64 years) in the ED requires a nuanced approach. Older patients are often more sensitive to medication effects and side effects. They tend to have more comorbid conditions, higher rates of polypharmacy, and reduced physiological reserves. The primary focus of pain management in geriatric patients is to minimize potential harm while providing effective, multi modal analgesia.

Challenges in geriatric pain management in the emergency department

Older adults often present to the ED with acute pain, yet they consistently receive less adequate pain management compared to younger patients.[136 138] These challenges in safely assessing and managing pain in this population [Table 7] necessitate a carefully crafted approach to pain management that considers the unique characteristics and needs of each patient.

Table 7. Challenges to safely managing pain in older adult patients

Approach to assessing pain in the emergency department

In patients able to communicate, pain can be assessed via different tools and pain scales, such as a numeric scale or Visual Analog Scale.[139 140] However, these scales are highly subjective, fail to capture personal and cultural differences, and do not convey the patient’s wishes or needs regarding medication administration. A simple, useful approach can be to ask the patient if they need medication for pain. If they answer affirmatively, a follow up question can be to inquire what has worked well for their pain in the past. For patients with moderate to severe dementia, unable to give a verbal account of their pain, the Pain Assessment in Advanced Dementia Scale (PAINAD) and Abbey Pain Scale, relying on nonverbal cues to pain, such as body positioning, moaning, or facial expressions, are found to be valuable.[141,142]

Approach to pain management in older adults

A useful framework for managing pain in older adults is to use a patient centered, holistic, and diverse therapeutic approach that considers potential drug patient, drug disease, and drug drug factors and interactions.

Patient centered

Putting patients’ desires and interests at the center of conversation by asking what matters the most to them will align clinicians’ care with the patient’s goals. Incorporating what matters to the patient is a cornerstone of the Age Friendly Health Systems’ “5 Ms” framework that includes: mentation, mobility, medications, multi complexity, and what matters most.[143]

Holistic

Pain and the experience of suffering are multifactorial and personal, and can be exacerbated by emotional distress and other unmet needs. Identifying whether pain is acute or chronic, neuropathic or nociceptive, visceral or somatic can help guide treatment selection. In addition, it is important to address the patient’s other needs, such as food, hydration, and physical comfort.[136,143]

Drug patient effects

When selecting a medication and dose, consider potential interactions between the drug and the patient, such as the patient’s baseline level of frailty or physiologic reserves, their underlying fall risk, and whether they have physiologic tolerance or are naïve to a given class of medications.[136,137]

Drug disease effects

Renal, hepatic, or cardiac dysfunction; peptic ulcer disease; orthostatic hypotension; and delirium may necessitate medication adjustments. For example, NSAIDs can cause acute renal failure, particularly in the setting of chronic kidney disease (CKD). NSAIDs can also worsen gastritis and peptic ulcer disease. They can also interact with ACE inhibitors, diuretics, steroids, and warfarin, potentially increasing INR for patients on warfarin.

Renally cleared opioids such as oxycodone, hydrocodone, and morphine should be used cautiously in patients with chronic kidney disease or end stage kidney disease, as the medication or its metabolites can have prolonged or more severe adverse effects or sedation.[144]

Drug–drug effects

When prescribing medications for use over time, as well as a single dose in the ED, it is important to review the patient’s home medication list to look for potential medication interactions. For pain management, high risk combinations to avoid to prevent oversedation, respiratory depression, or other side effects include opioids with gabapentinoids, muscle relaxants, or benzodiazepines.[136,143]

A tiered treatment approach

After assessing the patient’s source, severity, and chronicity of pain, aligning with patient goals, and reviewing the underlying drug patient, drug drug, and drug disease factors, emergency clinicians should employ a tiered approach to safely managing their pain. Commonly used analgesics with their starting doses and routes of administration are summarized in Table 8.

Table 8. Common analgesics with routes of administration and starting doses

Nonpharmacologic approaches

Addressing unmet physical or emotional needs can help reduce the experience of suffering. Simple interventions such as adjusting the bed or chair for physical comfort, providing warm blankets, and addressing hunger, thirst, or toileting needs. Heating pads, distraction, or reassurance can be useful as well.[143]

Pharmacologic approaches

Targeted approaches

Certain types of pain are particularly amenable to targeted approaches. For example, femoral or fascia iliaca nerve blocks offer effective analgesia for hip fractures, reducing opioidconsumption.[145] Nerve blocks may also be appropriate for other fractures (upper extremities, ribs) or prior to procedures, repairs, or reductions.

Topical approaches

Topical agents, such as diclofenac, can be used alone or as adjuvants for many painful MSK disorders, such as sprains and strains. Topical diclofenac is effective, well absorbed locally, has little systemic absorption, and reduced side effects.[146] Topical lidocaine patches are effective for postherpetic neuralgia and other neuropathic pain disorders. Lidocaine patches are also useful in chest wall trauma and rib fractures and lead to a decrease in opioid use.[147,148]

Systemic nonopioid medications

Acetaminophen is a common first line medication for mild or moderate pain in older adults, as there are few side effects and medication interactions, and it can be used in patients with renal disease. It can be given orally or intravenously and can be used in conjunction with other pain medications for a multi modal approach.[149]

NSAIDs administered orally or parenterally are effective for pain control in the elderly in the ED, with caution in patients with gastric ulcers or renal impairment. NSAIDs are particularly effective for renal colic and other nociceptive (rather than neuropathic) pain.[150] Drug disease and drug patient factors should be closely considered before longer term prescribing, as NSAIDs are involved in close to 25% of adverse drug reactions leading to hospitalization.[151]

Ketamine, when used for acute pain in the ED, provides analgesia comparable to morphine but caries a higher risk of psycho perceptual side effects such as dizziness, light sedation, or feelings of unreality,[152] with one third of older patients requiring discontinuation of the ketamine due to the effects.[153]

Gabapentin or pregabalin can be effective for neuropathic pain, but their dosing requires titration. Combinations with benzodiazepines or opioids should be avoided or used with extreme caution.[154]

Systemic opioid medications

Opioids can be used alone or in conjunction with other treatment modalities for acute moderate or severe pain. Opioid medications carry the risk of sedation, urinary retention, and respiratory depression acutely, as well as tolerance and addiction with chronic use. It is generally wise to begin with a lower initial dose, monitoring, and frequent titration as needed to avoid respiratory depression or sedation.[155]

Opioids should also be used for the shortest duration necessary to avoid the risk of addiction or dependence. Tramadol is a weak mu opioid agonist that is commonly prescribed in the outpatient setting. However, it has significant potential side effects for older adults, including hypoglycemia, hyponatremia, lower seizure threshold, and higher mortality, so it should generally be avoided in favor of safer alternatives.[156,157] Certain opioids, such as oxycodone and hydromorphone, tend to create more euphoria compared with hydrocodone and morphine, which could lead to higher abuse potential.[158]

When prescribing opioids on discharge, it is important to also prescribe a bowel regimen. A combination of stimulant laxatives, such as senna, and/or an osmotic laxative such as polyethylene glycol, is effective.[159] For patients who require longer term opioid use or who fail stimulant laxatives, peripherally acting mu opioid receptor antagonists like methylnaltrexone, naldemedine, or naloxegol may be indicated.[160]

Conclusion

Effective pain management for older adult patients in the ED requires a comprehensive approach that balances efficacy with safety. By understanding and addressing the unique challenges faced by this population, clinicians can improve patient safety and enhance the quality of care for elderly patients experiencing acute pain. Clinicians should take a patient centered, holistic approach and consider drug patient, drug disease, and drug drug interactions to help ensure they are selecting the best medication, dose, and duration for each patient.

Take home pearls

1. Thorough assessment: Use a holistic approach to assessing a patient’s pain, their desires, and what matters most to them. Both verbal and non verbal indicators are important, especially in patients with cognitive impairment

2. Individualized treatment plans: Develop treatment plans that consider the patient’s overall health, current medications, and personal preferences. Incorporate both pharmacologic and nonpharmacologic approaches

3. Dosing strategy: Start with the lowest effective dose, particularly with opioids and sedatives. Reassess or monitor patients frequently and avoid long term prescriptions when possible

4. Education and communication: Ensure that patients and caregivers understand the treatment plan, potential adverse effects, and the importance of follow up. On discharge, communicate potential adverse effects and dosing adjustments with the patient and caregiver, such as the risk of dizziness or falls

5. Discharge management: For patients who are prescribed an opioid, it is important to also prescribe a stimulant bowel regimen.

Therapeutic strategies at discharge

While each of the unique and challenging populations requires an individualized treatment plan at discharge from the ED, several important concepts are uniformly applicable to all of them. At discharge, ED clinicians should engage patients in shared decision making about the nature of their painful syndromes and their expectations with respect to pain relief and functional improvement; commonly used analgesic modalities and their alternatives, as well as short and long term adverse effects; and the importance of outpatient follow up with the specialists (obstetricians and gynecologists, hematologists and sickle-cell specialists, oncologists and palliative care specialists, geriatricians, and pain management specialists with expertise in pain management of these vulnerable groups). In addition, ED clinicians should emphasize the need to return to the ED for re evaluation in the absence of acceptable pain relief and/or development of severe adverse effects related to prescribed analgesics.

Summary

Effective pain management in special populations requires emergency physicians to adopt tailored approaches that acknowledge the unique physiological, pharmacological, and psychosocial factors affecting these vulnerable groups. For pregnant patients, SCD patients, geriatric individuals, and those requiring cancer or palliative care, standard pain management protocols often prove insufficient or potentially harmful. Implementation of population specific pain management strategies, early multimodal analgesia, appropriate utilization of non pharmacological interventions, and interdisciplinary collaboration are essential components of optimal care.

As emergency medicine continues to evolve, further research focusing on these special populations will be critical to developing more refined, evidence based pain management strategies that would improve patient outcomes, minimize adverse effects, and address the persistent disparities in pain management that these populations frequently encounter.

How to cite this article: Vlasica K, Hall A, Rehman MA, Notas G, Shenvi C, Motov S. Emergency department pain management in special populations. Turk J Emerg Med 2025;25:159-77.

Author Contributions

KV: Writing original subchapter (lead); review and editing of the entire paper (equal). AH: Writing original subchapter (lead); review and editing of the entire paper (equal). AR: Writing original subchapter (lead); review and editing of the entire paper (equal). GN: Writing original subchapter (lead); review and editing of the entire paper (equal). CS: Writing original subchapter (lead); review and editing of the entire paper (equal). SM: Conceptualizing the entire paper (lead), review and editing of the entire paper (equal); preparing and editing the final draft (lead).
All authors made substantial contributions to the concept of the work, to manuscript preparation and revisions. All authors have approved the submitted version. All authors have agreed both to be personally accountable for the author’s own contributions and to ensure that questions related to the accuracy or integrity of any part of the work, even ones in which the author was not personally involved, are appropriately investigated, resolved, and the resolution documented in the literature.

Conflict of Interest

None Declared.

Financial Disclosure

None.

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