INTRAOPERATIVE OXYGEN USE DURING CESAREAN SECTION UNDER SPINAL ANESTHESIA

Objective. To evaluate the efficiency of oxygen use to reduce the incidence and severity of intraoperative nausea and vomiting (IONV) in patients who had spinal anesthesia (SA) during cesarean section (CS). Subjects and methods. A sample of two hundred 18-to-40-year-old preg-nant women at 38— 42 weeks gestational age without comorbidity who had been electively operated on and who had standardized neuroaxial anesthesia was formed. All the patients were randomized into two groups. The exclusion criteria were vomiting one hour before CS; the use of antiemetic drugs 24 hours before surgery; hemoglobin oxygen saturation below 90%; persistent systolic hypoten-sion below 100 mm Hg or 20% of the baseline blood pressure after twice ad-ministration of vasopressors; transition to general anesthesia; considerable sur-gical design changes or any study protocol breaches made by an anesthesiolo-gist in the interest of the patient. The degree of nausea was rated by the patients as mild (grade 1), moderate (grade 2), or severe (grade 3). Vomiting was regarded as mild (grade 4) if there were 1—2 episodes and as a severe (grade 5) if there were more than 2 episodes throughout the study. The statistical analysis of the findings comprised descrip-tive statistics for each examined indicator and the testing of the hypothesis for the statistical significance of the difference for the mean between two groups, by using the Student’s t-test at a significance of level of 0.05. The frequency characteristics of samples were calculated to compare the frequencies of com-plications. The whole processing of the data was made using the software pack-ages Microsoft Office Excel 2007 and STATISTICA 5.0. Results. The examined groups were statistically homogeneous in terms of age-related, anthropometric, and obstetric characteristics. Surgery and anesthesia were accompanied without complications. All the patients achieved an adequate level of anesthesia; the development of sensory block was within Th4—Th6. In the non-oxygen group, the incidence of mild nausea was 3 times more common than in the oxygen group. Mild vomiting was seen more frequently in Group 1. The rate of severe vomiting was identical at each time interval in both groups. A large number of cases without IONV episodes were noted in Group 2. The low-est rate of IONV was observed in a group of patients who inhaled moistened oxygen in a volume of 5 liters per minute as compared with the non-oxygen group. Conclusion. Additional oxygen inhalation during CS under SA reduces the rate and severity of intraoperative nausea or vomiting.

intraoperative nausea and vomiting, oxygen