Sublingual fentanyl: the solution to the analgesic gap in procedural pain

Procedural pain management in burns for short, (< 30 minute) severe intensity, repeated procedures is a significant challenge. Difficulties arise around the use of fixed drug and route regimes. An audit revealed an analgesic gap whereby such procedures were poorly served by conventional methods (inhalational nitrous oxide and oxygen - Entonox, oral morphine or general anaesthesia.) A literature search to identify the optimal form of sedo-analgesia was undertaken using key words including burns procedure, procedural pain, analgesia and burn injury, from 1950 – 2011. Sublingual fentanyl was identified as the best potential intervention to bridge the analgesic gap in burns. Following approval by the hospital’s New Medicines Committee and informed consent, a 19 year old male with 31% TBSA underwent a trial of sublingual fentanyl for hand therapy. The patient’s therapy had failed previously with oral morphine (inadequate analgesia and prolonged post therapy sedation) and inhaled nitrous oxide: oxygen in a 50:50 mixture (loss of consciousness negating participation in the therapy). Initial sessions using 100 and 200 micrograms of sublingual fentanyl required supplemental conventional analgesia. However, 300 micrograms was adequate as sole therapy for the remaining seven sessions, without changes in vital signs or opioid side effects. A marked objective improvement in hand function, assessed using the Kapandji scale was observed. Sublingual fentanyl mirrors the nature of procedural pain, thus filling the analgesic gap. Use of sublingual fentanyl may be guided by the triage of procedures and therapies using the novel concept of the Procedural Pain Matrix. Its use is favored by its pharmacokinetic profile, familiarity, cardiovascular stability and ease of titration, with minimal side effects. It aids engagement in therapy and may reduce healthcare costs in burns. Its use in other forms of procedural pain such as skin grafting, wound debridement and dressing changes requires investigation.