Effect of atropine upon the cerebrovascular system during soman-induced respiratory depression.

The effect of soman-induced respiratory depression upon cerebral vascular physiology was studied in monkeys. There was a significant decrease in heart rate, mean arterial blood pressure, cerebral blood flow and cerebral perfusion pressure during the onset of respiratory depression, which terminated as apnea. Administration of atropine resulted in an immediate increase in all of the above mentioned parameters which coincided with improvement in respiration. It was concluded that soman impaired cerebral autoregulation, caused a decrease in cerebral blood flow and cerebral perfusion pressure. It was suggested that respiratory depression resulted, in part, from anoxia. Administration of atropine increased the cerebral blood flow and cerebral perfusion pressure, which in turn, possibly reversed the anoxic conditions resulting in the improvement of respiration.