End-tidal carbon dioxide levels under surgical drapes during local eye surgery: Retrospective study

Objectives: To investigate the end tidal carbon dioxide pressure values in order to determine carbon dioxide accumulation under surgical drapes and it's hemodynamic effects based on anesthetic and surgical records in eye surgeries under local anesthesia Design: Retrospective study Setting: Department of Anesthesiology and Reanimation, Duzce Medical Faculty, Duzce, Turkey Subject: The data were collected from anesthetic records of patients (n=42) who were followed with noninvasive capnography in the operating room at Duzce University Hospital during the period of January 2016 to December 2016. Systolic, diastolic and mean arterial pressure, operation time, heart rate, ST segment analysis, ETCO2 pressure, pulse oximetry values were recorded. Time periods were determined as: after the anesthesia and before drape closure (baseline level), at 10th, 15th, 20th, 45th of the surgery and 5 minutes after drape removal. Intervention: Non-interventional Main outcome measure: Carbon dioxide accumulation under drapes and it's hemodynamic effects in eye surgeries under local anesthesia. Results: The comparisons were made with basal status and time periods statistically. No differences were found between mean arterial pressures, heart rates, arrhythmias and pulse oximetry values of patients between time periods. We observed significant differences for ETCO2 levels between basal and the other time periods, except when the drapes were removed (P=0.001). Conclusion: Routine monitorisation of ETCO2 with noninvasive capnography provides early detection of CO2 accumulation and CO2 rich air breathing during ophthalmic surgery.