Intra Nasal Sufentanil Versus Intravenous Morphine for Acute Severe Traumatic Pain Analgesia in Emergency Setting

Intranasal spray with one spray, equivalent to an half-dose. Patient receives simultaneously IV placebo administration and IN sufentanil spray. Pain is controlled by: * at 0 minute : Sufentanil IN 0,3µg/kg (2 sprays, one spray in each nostril) + NaCl 0,9% IV * at 10 minutes and if NPRS\>3 : Sufentanil IN 0,15µg/kg (1 spray) + NaCl 0,9% IV * at 20 minutes and if NPRS\>3: Sufentanil IN 0,15µg/kg (1 spray) + NaCl 0,9% IV

Intravenous administration Patient receives simultaneously IV placebo administration and IN sufentanil spray. Pain is controlled by: * at 0 minute : Sufentanil IN 0,3µg/kg (2 sprays, one spray in each nostril) + NaCl 0,9% IV * at 10 minutes and if NPRS\>3 : Sufentanil IN 0,15µg/kg (1 spray) + NaCl 0,9% IV * at 20 minutes and if NPRS\>3: Sufentanil IN 0,15µg/kg (1 spray) + NaCl 0,9% IV

Intranasal spray with one spray, equivalent to an half-dose. Patient receives simultaneously IV morphine administration and IN placebo spray. Pain is controlled by: * at 0 minute : Placebo IN (2 sprays, one spray in each nostril) + morphine IV 0,1mg/kg * at 10 minutes and if NPRS\>3 : Placebo IN (1 spray) + morphine IV 0,05mg/kg * at 20 minutes and if NPRS\>3: Pacebo (1 spray) + morphine IV 0,05mg/kg