Remifentanil Prevents Tourniquet-Induced Arterial Pressure Increase in Elderly Orthopedic Patients under Sevoflurane/N2O General Anesthesia

摘要

Aims: Prolonged tourniquet inflation produces a hyperdynamic cardiovascular response. We investigated the effect of continuous remifentanil infusion on systemic arterial pressure, heart rate, and cardiac output changes during prolonged tourniquet use in elderly patients under sevoflurane/N₂O general anesthesia. Methods: Thirty female patients scheduled for knee replacement arthroplasty were infused with either remifentanil at a target organ concentration of 2.0 ng/mL (remifentanil group, n = 15) or saline (control group, n = 15) after induction of anesthesia. Anesthesia was maintained with sevoflurane and N₂O. Heart rate (HR), systolic arterial pressure (SAP), diastolic arterial pressure (DAP), cardiac index (CI), total systemic vascular resistance index (TSVRI), BIS, end-tidal sevoflurane concentration (EtSEVO), and end-tidal carbon dioxide concentration (EtCO₂) were measured during the study period. Results: There were significant differences in mean HR, SAP, DAP, and EtSEVO over time between the groups (P = 0.047, P 2O general anesthesia.