Comparative Study between Sevoflurane and Isoflurane on Myocardial Protection Open Heart Surgery

Abstract Background: Numerous mechanisms for myocardial pro-tection associated with volatile anaesthetic administration have been proposed. However, research on the effects of sevoflurane and isoflurane on myocardial protection yielded contradictory results. Aim of Study: The purpose of this study is to compare the myocardial protective effects of sevoflurane and isoflurane in CABG surgery. Patients and Methods: This prospective randomized clinical double blind study included 106 patients, selected from the attendees of Al-Azhar University Hospitals during the period between December 2021 till June 2022. The study protocol was approved by the Local Ethics Committee and written informed consents were obtained individually. A sample of 106 patients were randomly allocated in equal numbers to receive either sevoflurane or isoflurane. We evaluated the patient demographic and baseline characteristics, including age, sex, body mass index (BMI), American Society of Anaesthesiology (ASA) physical status, Ejection Fraction, and the preoperative medications. Heart rate (HR), systolic, mean and diastolic arterial pressures (SAP, MAP, DAP) readings were recorded at different time points. In addition, Troponin-T, creatine kinase (CK), and CK-MB were measured in all blood samples before induction of anesthesia, after aortic unclamping, 12 and 24 hours postoperatively. Echocar-diograph for all patienta 24h postoperative to evaluate the myocardial function. Results: No significant difference was reported between both groups regarding the demographic characteristics. Base-line Heart rate was comparable between the two study groups with no statistically significant difference. Heart rate recordings showed more stability in the sevofluran group. Troponin-T, CK and CK-MB were investigated prior to the surgery, after removal of the cross-clamping, 12 and 24 hours postoperatively. The three cardiac enzymes showed comparable efficacy at baseline, with non-significant results. After declamping, Troponin-T, CK and CK-MB increased in both groups, but higher recordings were significantly reported in the isofluran group.
Conclusion: During CABG surgery, sevoflurane has a greater cardioprotective effect than isoflurane. When compared to isoflurane, sevoflurane was associated with greater stability and fewer variations from baseline. The better myocardial protection associated with sevoflurane is inferred by the lower levels of the myocardial injury markers troponin-T, CK, and CK-MB, observed with sevoflurane, compared to isoflurane. Further high quality studies are needed to determine the potential impact of the volatile anaesthetic regimen selection on long-term cardiac function after CABG surgery.