Evaluation of Effect of End Tidal Carbondioxide (Etco2) Monitoring on Patient's Safety during Propofol and Fentanyl Based Sedation for Short Surgical Procedures Compared to Standard Monitoring- An Observational Study

Background: Currently, day care procedures are more frequently performed under procedural anaesthesia. It helps patient to tolerate unpleasant or painful procedures, avoiding intraoperative awareness. Compared to general anaesthesia, PSA may be linked with an even higher incidence of major sedation-related adverse events. Frequent monitoring is advised because sedation-induced depression of the central nervous system may compromise respiratory function. Even with low breathing frequencies, oxygen saturation is commonly maintained, and respiratory depression, hypoventilation, and apnoeic episodes are usually missed by pulse oximetry. With the aid of non-invasive EtCO2 monitoring, CO2 retention and hypoventilation can be identified early and appropriate action can be taken. However, in many places, EtCO2 monitoring is not a standard procedure during PS [2,3]. Hence, we have focused to evaluate the effect of EtCO2 on patients’ safety in terms of CO2 retention and apnoeic events in propofol and fentanyl-based sedation for short surgical procedures as compared to standard monitoring. Objective: To evaluate whether EtCO2 monitoring decreases the incidences of CO2 retention and apnoeic events in propofol and fentanyl-based sedation in short surgical procedures as compared to standard monitoring. Methods: 80 patients between 18-65 years age of either gender with ASA status I and II posted electively for short surgical procedure and receiving total intravenous anaesthesia using propofol and fentanyl were selected. The patients were randomly divided into two groups. Group A: Patients monitored with end tidal CO2 in addition to standard monitoring. Group B: Patients monitored with standard monitoring. All patients were administered drugs according to the standard protocol. Baseline vitals were noted and ABG was done. Thereafter vitals were recorded at 5 min interval till 30 min and ABG at 15 min and end of the procedure. Results: CO2 retention occurred significantly less often in the EtCO2 monitoring group. In the standard monitoring group, the mean PaCO2 was more than 45mmHg and the pH was less than 7.35 at 15 min after induction of anaesthesia and at the end of the procedure. Both values were within the normal range in the EtCO2 monitoring group. The number of airway interventions performed was significantly higher in the EtCO2 monitoring group. Apnoea occurred less often in the EtCO2 monitoring group and recovery time was shorter. Conclusion: The addition of EtCO2 monitoring to standard monitoring during propofol-based sedation can improve patient safety by decreasing the incidence of CO2 retention, and therefore the risk of hypoxaemia through early recognition of apnoea, and can also shorten recovery time.