The effect of hyperbaric oxygen on acute experimental sulfide poisoning in the rat

In order to evaluate the efficiency of hyperbaric oxygen in experimental acute sulfide poisoning, we studied the effect of 1 ATA (atmosphere absolute) oxygen and sodium nitrite therapy. We then studied the effect of oxygen at 3 ATA alone and in combination with intraperitoneal sodium nitrite injection on rats poisoned by intraperitoneal injection of LD75 sulfide. Electroencephalogram and heart rate were continuously monitored. We also studied the effect of sodium nitrite and hyperbaric oxygen administered before the poisoning (protective effect). In our experimental set, death of untreated poisoned animals occurred within 5 min. There is a parallel between modification of the EEG pattern and apnea. Respiratory arrest always preceded cardiac arrest. Pure oxygen (1 ATA O2) is effective in preventing death in experimental sulfide poisoning. 3 ATA oxygen was significantly more effective in preventing death than 1 ATA oxygen, or sodium nitrite alone. The best therapeutic regimen was a combination of 3 ATA oxygen and sodium nitrite administration.