Respiratory Failure of Acute Organophosphate and Carbamate Poisoning: Discussion (2)
In man, the failure of the central respiratory drive seems to be the most important factor, and the peripheral neuromuscular block is a secondary factor for RF. The initial respiratory symptoms as described above and final RF always developed during the period of cholinergic crisis, usually during the first 24 hours after exposure to organophosphate. But Wadia et al and Senanayake et al described intermediate neurotoxic effects, the paralysis of proximal limb muscles, neck flexors, motor cranial nerves, and respiratory muscles, occurring 24 to 96 hours after poisoning, after recovery from cholinergic crisis while still receiving atropine treatment. buy diabetes drugs
Most patients with these intermediate neurotoxic effects developed RF and more than half of the patients with RF died. Although the initial cholinergic phase responded well to atropine alone, the intermediate neurotoxic effects did not respond to atropine. Respiratory failure developed in 40.2 percent of our patients, an incidence similar to previous reports.- In nearly 80 percent of these cases, the RF developed during the first 24 hours after exposure; it may have occurred due to the muscarinic and nicotinic effects of the acute organophosphate poisoning. The mortality rate was particularly high (57.1 percent) in this group. Of the remaining eight patients whose RF developed between 24 and 96 hours after exposure, only two died.