Observational Cross-Sectional Study of ETCO2 and Pulse Oximetry for Early Detection of Hypoxia in MAC Patient (Monitored Anaesthesia Care)

Background and Aim: The study aims to identify whether ETCO2 detects early hypoxia compared to monitoring of SpO2, HR and RR (Standard Monitor) in patients undergoing surgical procedure under MAC. Method: Total 336 patients belonging to Age group of 18-60 years, ASA grade 1 and grade 2, procedure lasting for <4hrs, undergoing sedation under MAC for day care surgery. Measurements of Spo2, HR, RR, ETCO2, NIBP done by applying monitors. Nasal cannula also put for supplemental Oxygen. Result: Overall 92 episodes of disordered ventilation were detected out of which 67 were detected by ETCO2 (44- Hypoventilation and 23- Apnoea) and 25 were detected by Pulse Oximetry (4- Hypoventilation and 21- desaturation. Overall a mean delay of 51.04 seconds was seen in detection by Pulse Oximetry. Conclusion: In the study it was concluded that patients under sedation, underwent frequent episodes of disordered ventilation leading to hypoxia. In such scenarios it was seen that ETCO2 monitoring provided a practical advantage of detecting hypoventilation and apnea earlier than Pulse Oximetry showing desaturation. Keywords: Capnography, ETCO2, pulse oximetry.