Changes on QT, Qtc and P Dispersion during Flexible Bronchoscopy under Propofol and 12121 Remifentanil Sedation. A Double-Blind Randomized Trial

Abstract

Background: Serious hemodynamic alterations have been shown during flexible fiberoptic bronchoscopy (FFB). QT and P wave dispersion (QTd, Pd) may give us an significant information about cardiac status during FFB. This study aimed to compare the effect of propofol and remifentanil sedation on QTd, corrected QT dispersion (QTcd) and Pd during FFB.Method: Forty-nine ASA class I or II patients who were not pre-medicated were selected and allocated to receive either propofol 1 mg/kg (n=20) or remifentanil 1 µg/kg (n=20) and titrated to achieve Ramsey sedation score level of 5. QTd, QTcd and Pd were measured on electrocardiography baseline (T0), at the end of the infusion of drugs (T1), shortly after laryngoscopy (T2), at the end of bronchoscopy (T3) and the time of Modified Aldrete score to be achived 10 (T4) Heart rate, mean arterial pressure, respiratory rate and partial CO2 pressure in blood gas were recorded at these time points. Furthermore, recovery times (RT) were recordedResults: QTd at all measurement times, corrected QTd at T1 and T2, P dispersion at T1, T2 and T3 increased significantly in the propofol group compared to remifentanil group (p<0.05). Mean arterial pressure increased significantly in the propofol group compared to the remifentanil group at T2 (p<0.05). There was a significant decrease in respiratory rate at T1 and T3 in the remifentanil group (p<0.05). There were no significant differences in heart rate and partial CO2 pressure between groups. RT was shorter in the remifentanil group (p<0.05). Conclusion:Remifentanil shortened and propofol prolonged QTd, QTcd and Pd at sedative doses during FFB. Also we obtained the short RT with remifentanil. So remifentanil may be more suitable sedative agent during FFB.