Comparison of two method of ventilation " Bag mask ventilation" and " Mapelson B circuit ventilation" on O2 saturation of patients undergoing Electro Convulsive Therapy (ECT)

Electro Convulsive Therapy (ECT) is one method for treatment of some psychiatric disorders. Because ETC performed during general anesthesia, oxygen therapy during ETC have an important role. Previous studies showed that some patients experience hypoxemia during ETC that could cause side effect in patients. In this study effectiveness of two ventilation methods (bag mask ventilation and semi close Mapelson circuit B) during ETC and effect of these two methods on patients O2 saturation were compared. In a single-blind randomized controlled trial 72 patients under ECT were randomly assigned into two groups A and B. While patients in group A were ventilated wit Mapelson B and patients in group B ventilated with bag mask ventilation. Patients O2 saturation were measured in times “before anesthesia, after anesthesia induction, after colonic phase of seizure, and every one minute to ten minute after seizure” with using pulse oximetry apparatus. Demographics variable were similar between groups (p>0.05). Results showed that level of O2 saturation were higher significantly in all time in patients in group A (Patients who were ventilated with Mapelson B circuit in compared to patients in group B except 7 and 8 minute after seizure (p<0.05). Rate of hypoxemia during ETC decreased with using Mapelson B ventilation circuit in compared to use bag mask ventilation.