The incidence of bradycardia during endoscopic third ventriculostomy

The incidence of bradycardia during endoscopic third ventriculostomy (ETV) is unknown. In an attempt to determine that incidence, we studied 49 pediatric patients with obstructive hydrocephalus who underwent ETV during general anesthesia. The median age was 54.5 mo (range 1-108 mo) and the median weight was 12.2 kg (range 2.4-22 kg). The heart rate was measured continuously in which four stages were identified for data analysis. Stage A is the preoperative phase, stage B is 5 min before perforating the floor of the third ventricle, stage C during perforation, and stage D after perforating the floor of the third ventricle. Three readings were recorded at each stage, then averaged. The mean values of the heart rate at stages A, B, C, and D were 146 +/- 27, 151 +/- 26, 87 +/- 32, and 143 +/- 24 bpm respectively. A significant decrease in the heart rate was determined in stage C compared with stage B (P: < 0.05). The incidence of bradycardia was 41%. Alerting the surgeon to perforate the floor of the third ventricle or withdraw the scope away from it was sufficient to resolve the bradycardia. We concluded that serious bradycardia might occur during ETV, mostly because of mechanical factors and can be resolved without medications.

The use of endoscopy for treating pediatric patients with increased intracranial pressure is a new surgical procedure. These patients require general anesthesia with continuous heart rate monitoring. We have observed a high incidence of decrease in heart rate. If a decrease in heart rate occurs, alerting the surgeon to speed the procedure would be an effective treatment.