Comparison of effects of patient positions on haemodynamic effects, early complications and brain oxygenation in spinal anesthesia practice in caesarean surgery

In our study, we aimed to identify the haemodynamic effects and possible complications of spinal anesthesia procedure performed in both sitting and lateral decubitus positions and to determine whether there is a correlation between these effects and brain oxygenation monitorization which continues during procedure and operation. The study was performed in a prospective manner as comparing two groups which involve a total of 136 patients between 18-50 years old and in ASA physical status I-II risk group. 68 of the patients received spinal anesthesia in sitting position whereas the other 68 patients received spinal anesthesia in lateral decubitus position. Mean arterial pressure (mmHg), peripheral oxygen saturations (%), cerebral tissue oxygenation, nausea-vomiting; need for ephedrine, atropine, ondansetron as well heart rate (beat/min) of mother before anesthesia at; 1st, 5th, 10th, 15th, 20th minute of anesthesia and during delivery were recorded in all patients. Time of acquiring T6 sensory block, time of acquiring motor block (sec) (reaching Bromage III value) were also individually recorded. Intergroup and intragroup comparisons in terms of obtained data were statistically evaluated. According to the statistical analysis, we concluded that peripheral and cerebral hypoperfusion which may occur due to aortocaval pressure; may be less affected with spinal anesthesia performed in sitting position. As for the comparison of spinal anesthesia techniques performed in different positions; although peripheral oxygen saturation measurements were in normal range in both groups, there may be differences in cerebral oxygenation measurements. Although there was no statistical difference between two groups; we used more ephedrine in patients with lateral positions than patients with sitting positions in terms of number of patients who received ephedrine. In addition, we thought that cerebral oxymeter measurements were more valuable in terms of possible complications. In conclusion, we concluded that spinal anesthesia performed in sitting positions affects inraoperative brain oxygenation less than spinal anesthesia performed in lateral decubitus position in elective caeserian operations.