THE RELATIONSHIP BETWEEN END-TIDAL CARBON DIOXIDE LEVELS AND PATIENT POSITIONS

Introduction: End-tidal carbon dioxide partial pressure is a widely used measurement in clinical practice to monitor the current condition of the respiratory system. The aim of the present study is to demonstrate the changes in the levels of end-tidal carbon dioxide partial pressure during supine, Trendelenburg, and reverse Trendelenburg positions in healthy individuals. Materials and methods: The end-tidal carbon dioxide partial pressure were measured in supine, Trendelenburg (30%), and reverse Trendelenburg (30%) positions using a facemask connected to an anesthesia machine (Siemens Kion, Sweden) after fixing the patient on the related position for five minutes. A 30-minutes resting period was provided to the patient for the accuracy of the end tidal carbon dioxide partial pressure measurements following each positioning. Results: The mean end-tidal carbon dioxide partial pressure level in reverse Trendelenburg position was significantly lower than in supine position (p < 0.01). The mean end-tidal carbon dioxide partial pressure level in Trendelenburg position was found to be higher when compared to reverse Trendelenburg position (p < 0.01). In supine and Trendelenburg positions, the mean end-tidal carbon dioxide partial pressure level was higher in males than in females (p = 0.026 and p = 0.043, respectively). Conclusion: The findings of the present study revealed that Trendelenburg position may cause increased end-tidal carbon dioxide partial pressure levels while reverse Trendelenburg leads to a decrease in levels.