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9.9 ACUTE PAIN MANAGEMENT IN EMERGENCY

DEPARTMENTS

Pain is the most common reason for presentation to the emergency department and many
patients will self‐medicate for pain before attending (Kelly & Gunn, 2008). There is evidence
that, as in many other areas of health care, patients in emergency departments around the
world receive suboptimal pain management (Todd et al, 2007). Although 70% of patients
presenting to an emergency department rated their analgesia as ‘good’ or ‘very good’, patient
satisfaction with analgesia did not correlate with pain scores at presentation or discharge, or
change in pain scores (Kelly, 2000 Level IV).
In the emergency department setting, analgesia should be simple to administer, condition‐
specific and where possible based on local‐regional rather than systemic techniques. Systems
should be adopted to ensure adequate pain assessment, timely and appropriate analgesia,
frequent monitoring and reassessment of pain and additional analgesia as required. For
example, the introduction of a protocol based fentanyl titration regimen improved timely and
effective delivery of analgesia in the emergency department (Curtis et al, 2007 Level II).

9.9.1 Systemic analgesics
Opioids
In the emergency department, opioids are frequently prescribed for the treatment of severe
pain and should preferably be administered via the IV route, given the wide interindividual
variability in dose response and the delayed absorption via the IM or SC routes. However,
IV and intraosseous morphine demonstrated similar pharmacokinetic profiles in adults (Von
Hoff et al, 2008 Level II). Doses should be adjusted for age (see Section 4.1) and titrated to
effect. Patients require close observation for sedation, respiratory depression and occasionally
hypotension (Coman & Kelly, 1999 Level IV).
There is no clear consensus on what constitutes the most effective IV opioid or dosing regimen
for analgesia in the emergency department. There was no difference between IV bolus dose
CHAPTER 9 care (Galinski et al, 2005 Level II). Similarly, in elderly patients attending an emergency
fentanyl or morphine in providing effective analgesia for up to 30 minutes during prehospital
department there were no differences in effects or adverse effects between IV bolus doses of
morphine or hydromorphone (Chang, Bijur, Baccelieri et al, 2009 Level II). The addition of ultra‐
low‐dose naloxone to bolus dose morphine failed to improve analgesia or reduce opioid
adverse effects (Bijur et al, 2006 Level II).
Titrating (relatively) high doses of opioid frequently to clinical effect provides the best chance
of delivering rapid and effective analgesia. Significantly more patients attained effective
analgesia at 10 minutes with the administration of 0.1 mg/kg morphine, followed by
0.05 mg/kg, 5 minutely, compared with those who received half these doses; however there
was no difference in analgesia outcomes at 30 minutes (Bounes et al, 2008 Level II). In non‐
elderly adults, a bolus dose of 2 mg hydromorphone IV provided good analgesia, but caused
oxygen desaturation in one third of patients (Chang, Bijur, Napolitano et al, 2009 Level III‐3); use
of a 1 mg bolus dose was slightly less effective but caused oxygen desaturation in just 5% of
patients (Chang, Bijur, Campbell et al, 2009 Level III‐3). IV opioid PCA was as effective as nurse‐
administered IV bolus dosing in the emergency department (Evans et al, 2005 Level II).
In children requiring analgesia in the emergency department, IN (Borland et al, 2007 Level II),
inhaled (nebulised) (Miner et al, 2007 Level II), or oral transmucosal (Mahar et al, 2007 Level II)
fentanyl provided effective analgesia (see Sections 6.6.1 and 10.4.4 for details). IN fentanyl

290 Acute Pain Management: Scientific Evidence