Brainstem death and ventilator trigger settings

A patient with cerebral infarction was certified clinically brainstem dead. However, 4 h after the diagnosis of death, while the patient was being ven tilated using the biphasic positive airway pressure mode, the 'assist' indi cator light on the Drager Evita 2 ventilator illuminated intermittently. Th ere was no evidence of spontaneous breathing. 'Triggering' was probably cau sed by a decrease in airway pressure in time with cardiac contraction. The trigger flow rate is crucial as factors other than the patient's inspirator y effort can initiate flow from the ventilator with very sensitive settings .