Effect of Different Oxygen Concentrations Used During Multicomponent Endotracheal Anesthesia on the Structural and Functional Parameters of Red Blood Cells
Objective: to study the effect of different concentrations of oxygen on structural and functional parameters of red blood cells during balanced multicomponent sevoflurane-based endotracheal anesthesia. Subjects and methods. The prospective, randomized trial enrolled 20 persons (aged 52.7±16.2 years) who underwent the same surgical procedure. The patients were divided into 2 groups, which differed inintraoperatively used oxygen concentration in the inspired mixture,50% FiO <sub>2</sub> (group 1) and 21% FiO <sub>2</sub> (Group 2). A morphological difractometric analysis of patients' red blood cells was performed preoperatively, intraoperatively, and after anesthesia. Results. In Group 1, red blood cells demonstrated statistically significant trend towards macrocytosis (82.4±23.3 fl before general anesthesia versus 85.1±20.6 fl after anesthesia; p=0.02); in group 2, there were no statistically significant changes in red blood cell volumes. Lateral light scattering was ignificantly decreased after anesthesia in Group 1 (146.2±17.7 U versus 162.9±23.0 U prior to anesthesia (p<0.005) and 156.4±16.3 U during the surgery (p<0.05)). The coefficient of variation in halfheight of lateral light scattering of red blood cells was also significantly increased at the final stage of observation in Group 1 (26.3±3.1 U versus 22.1±5.0 U during surgery, p<0.05 and 20.8±3.9 U before anesthesia, p<0.005). No significant changes in these two indicators were seen in Group 1. Conclusion: changes in shape and patterns of red blood cells occur intraoperatively under hypoxia, which are likely to be associated with the increasing level of prooxidants.