Inhaled vs IV Opioid Dosing for the Initial Treatment of Severe Acute Pain in the Emergency Department

Prospective single-blind, multicenter, national, randomized, controlled trial in 15 Emergency Department to compare two ways of morphine titration. The eligible patient is included immediately after his arrival in the Emergency Department, after being questioned by the triage nurse about the presence and the intensity of pain, when the VAS is greater than 70 (or EN\>7) and after written consent. After installation into the examination room, patient is randomized in one of two parallel groups (stratified by sex and center using software) and receives one of the two treatments, either inhaled morphine + IV placebo or IV morphine+ inhaled placebo (control group). In both groups, titration is defined by a dose of repeated boluses as long as the relief is not achieved (VAS\> 30 or EN \>3) and the criteria to stop titration are not met. A 5 minutes time interval between the boluses is chosen. Each aerosol takes 5 minutes at a constant air flow, aerosol mask, plastic tubing and PVC transparent tank are used. Thus patient receives a maximum of 3 aerosol (one aerosol every 10 minutes) and a maximum of 6 IV injections (one injection every 5 minutes) The stopping criteria, except pain relief, are linked to the occurrence of side effects and specific cares are described into the protocol (in case of severe ventilatory depression naloxone titration is provided). Exit criteria from the emergency room and from the hospital are defined. An information sheet is delivered.