It sometimes seems the rule, not the exception, that patients present with just enough idiosyncrasy or uniqueness to make standard approaches unavailable or ineffective. Consider the agitated arrestee with a history of dystonia and allergy to ketamine or the rapid a-fib with concomitant COPD exacerbation in our era of medication shortages and limited therapeutic resources. Whatever the situation, EPs are no strangers to the MacGyver task. In few areas does this demand for flexibility recur as often as in providing safe, effective, and judicious analgesia.
Typically, oral, intravenous, or intramuscular routes of analgesia are more than sufficient for our needs. Alternative routes of medication administration add an important tool in our arsenal, however, whether for their efficacy when intravenous access is difficult or unwanted or for their unique properties when delivered nontraditionally, such as in using furosemide via nebulization, which has been used with great success to mitigate air hunger in a variety of clinical situations. (J Hosp Palliat Nurs 2008;10:189.) Limiting the use of opioids remains a critical responsibility, and knowing and using alternate drug delivery methods offer a potential intermediary between opioid overutilization and oligoanalgesia.
The intramuscular route is nearly always available, but IM injections are a particularly poor mechanism of pain control. Medication absorption can be wildly variable via this route, and up to 25 percent of patients may have no response at all. (Pain 1980;8:47.) Repeated injections have been implicated in complications such as injection site abscess, nodule growth, hematoma formation, and myofibrosis. (J Bone Joint Surg Am 1980;62:58.)
Multiple studies have consistently demonstrated subcutaneous opioid administration to be at least as effective as the IM route, with several suggesting superior performance more closely matching IV delivery. One randomized trial found no difference in pain and nausea scores when comparing subcutaneous to IM morphine administration, but patients strongly preferred the subcutaneous route, which had fewer injection site reactions and less pain with injection. (Anaesth Intensive Care 1996;24:574.) Dilaudid has been shown to be more than 75 percent bioavailable when administered subcutaneously, with one trial arguing that its relative simplicity, technical advantages, and cost-effectiveness make it an attractive mechanism of pain control. (Lancet 1991;337:465.)
Intranasal and Inhalational Routes
Avoidance of parenteral administration is a not-infrequent goal, whether for pediatric populations, patients with a certain level of opioid familiarity, or in situations where the pain or danger of an uncapped needle is worth avoiding. Intranasal sedation has become nearly routine in many departments, but intranasal analgesia has curiously lagged behind. Intranasal fentanyl (1-1.5 mcg/kg), however, enjoys a mountain of data supporting its use, matching IV morphine in pediatric and adult investigations. (Ann Emerg Med 2007;49:335; Am J Emerg Med 2007;25:911.) One fascinating study from the dental literature showed no clinically significant difference in analgesia between intranasal and intravenous use. (Clin Ther 2008;30:469.)
When you want to avoid opioids, IN ketamine (0.5 mg/kg) is safe and effective for pain control (Acad Emerg Med 2010;17:194), and the recent PICHFORK study showed it was just as effective as IN fentanyl in controlling moderate to severe pain, though ketamine had more adverse events (mostly minor reports of dizziness). (Ann Emerg Med 2015;65:248.) Other opioid-sparing intranasal analgesics have also demonstrated profound efficacy, including desmopressin for renal colic (J Urol 1995;153:139) and dexmedetomidine, though these medications haven't penetrated typical practice, and likely will not until the cost improves significantly.
Unfortunately, sometimes we find the nasal atomizers many of us like are unavailable. Inhalational routes—nebulized medication—can still be used. Ideally a closed or jet nebulizer system should be used, but in a pinch the standard setup available everywhere is more than sufficient. Nebulized fentanyl (4 mcg/kg) has consistently demonstrated comparable analgesia to IV opioids. (Emerg Med Australas 2009;21:203.) The bioavailability of nebulized opioids generally requires a four- to fivefold increase in weight-based dosing, but efficacy is maintained without serious side effects. (Br J Anaesth 1988;61:228.)
Transmucosal analgesia with the venerable fentanyl lollipop has been a cornerstone of palliative medicine for decades. Used mostly in comfort care or hospice, small ED-based investigations have proclaimed success without the feared complications of overdose or overuse. (Ann Emerg Med 1991;20:111.) Buprenorphine, available as an oral dissolving film, also continues to see growing use as a safe partial opioid alternative. (Int J Emerg Med 2014;7:1.) Buccal, sublingual, and orally dissolving analgesics are most appealing in end-of-life care, but they provide EPs with another avenue for flexibility where traditional routes are unavailable or unattractive. Certainly, their ease of administration (without the need for needles, syringes, or other mechanisms of drug delivery) may be particularly beneficial in resource-limited settings.
“If you don't know three ways of doing everything, you don't belong in the ED.” I can't remember when I was given these words of advice, but hardly a shift goes by where I don't appreciate their wisdom, faced as often as we are with the eccentricities of our population. It's not every day these alternative routes of medication administration should make an appearance in your ED, but knowing how to employ them when other methods come up short can turn frustrating idiosyncrasy into just one more task we can easily MacGyver.