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and IV morphine were equally effective in reducing acute cardiac chest pain during prehospital
transfer (Rickard et al, 2007 Level II). In a study of patients with post‐traumatic thoracic pain,
there was no difference in analgesia between nebulised morphine and morphine PCA (Fulda et
al, 2005 Level II).
Opioid‐tolerant patients pose a special challenge in the emergency department and their
management is discussed in Section 11.7.
Tramadol
In the management of severe trauma pain, IV tramadol had similar analgesic efficacy
to morphine (Vergnion et al, 2001 Level II). In patients with right lower quadrant pain,
presumably due to appendicitis, parenteral tramadol reduced the mean VAS by only
7.7/100 mm compared with placebo, and did not affect the clinical examination (Mahadevan
& Graff, 2000 Level II). For renal colic, tramadol was as effective as parenteral ketorolac
(Nicolas Torralba et al, 1999 Level II) but less effective than pethidine (Eray et al, 2002 Level II).
For acute musculoskeletal pain, IM tramadol was similar to ketorolac in efficacy and side
effects, when both were combined with oral paracetamol (Lee et al, 2008 Level II).
Non-steroidal anti-inflammatory drugs
NSAIDs are useful for treating mild‐to‐moderate trauma pain, musculoskeletal pain, renal and
biliary colic and some acute headaches, as discussed elsewhere in this document (see
Section 4.2).
Inhalational analgesics
N 2O in oxygen (see Section 4.3.1) provided effective analgesia and anxiolysis for minor
procedures in both adults and children (Gamis et al, 1989 Level II; Gregory & Sullivan, 1996 Level II;
Burton et al, 1998 Level II; Gerhardt et al, 2001 Level II; Burnweit et al, 2004 Level IV) and may be
useful as a temporising measure while definitive analgesia is instituted (eg insertion of a digital
nerve block for finger injury).
Methoxyflurane (see Section 4.3) is used to provide analgesia, most commonly in prehospital
emergency care (see Section 9.10.1).
Ketamine
Ketamine‐midazolam was more effective and had fewer adverse effects than fentanyl‐
midazolam or fentanyl‐propofol, for paediatric fracture reduction in the emergency
department (Migita et al, 2006 Level I) (for more information see Section 10.4.4). CHAPTER 9
IV ketamine boluses produced a significant morphine‐sparing effect (without a change in pain
scores) when used to treat severe trauma pain in the emergency department (Galinski et al,
2007 Level II). When treating acute musculoskeletal trauma pain, a low‐dose, SC ketamine
infusion provided better analgesia with less nausea, vomiting and sedation, and improved
respiratory function, compared with intermittent SC morphine injections (Gurnani et al, 1996
Level II). IN ketamine provided effective pain relief (within 15 minutes); adverse effects were
mild and transient (Christensen et al, 2007 Level II).
For further information on ketamine, see Section 4.3.2.

9.9.2 Analgesia in specific conditions
Abdominal pain
Patients and physicians differ in their assessment of the intensity of acute abdominal pain in
the emergency department. Physician’s VAS estimates of abdominal pain were significantly
lower than the patient’s reports. Administration of analgesia correlated with the physician’s
assessment of a pain score greater than 60/100 mm on VAS. A patient’s satisfaction with
Acute pain management: scientific evidence 291