A randomised control study comparing the efficacy of 2 techniques of preoxygenation - tidal volume breathing for one minute and 8 deep breaths in one minute

Abstract

Introduction: The aim of preoxygenation is to replace nitrogen in the Functional Residual Capacity (FRC) with oxygen. This increases body oxygen store and increases tolerance to apnoea significantly. Materials and Methods: This study was conducted in PESIMSR, Kuppam between July 2012 and November 2013 in a selected population of 60 adults of either sex scheduled posted for elective surgery. The patients were distributed into 2 groups, Group Tidal Volume Breathing, T and Group Deep Breathing, D. Each group had 30 patients. Group T patients were preoxygenated with Tidal Volume Breathing and group D patients were preoxygenated with 8 deep breaths in 1 minute. The measured variables were SpO2, Heart rate, inspired oxygen concentration, Endtidal Oxygen concentration, End tidal Carbon Dioxide and Duration of Apnoea without desaturation (DAWD). Results: There were no statistically significant differences between both the groups in age, gender, height, weight and BMI. All the patients in both the groups attained ETO2 values of above 90 at the end of preoxygenation. The mean ETCO2 value in T group was 32.16 ± 1.51 and 27.36 ± 1.73 in Group D. This value was statistically significant with a p value of Conclusion: Preoxygenation with 8 deep breaths in 1 minute is a more effective method of preoxygenation because there is a significant increase in the time taken for desaturation. This method will be more effective in patients with full stomach posted for emergency surgery. Keywords: Tidal volume breathing, Deep breathing technique, Preoxygenation, Safe duration of apnoea.