Comparison of the effect of epidural anesthesia applied in two different volumes in lower extremity surgery on the intracranial pressure by measuring the diameter of the optic nerve sheath with ultrasound.

Regional anesthesia applications are being applied in increasing rates, especially in orthopedic surgeries. Consciousness of the patient, spontaneous breathing, and the use of postoperative analgesia have made regional anesthesia a preferred anesthetic method. It has become widespread over time, both by providing surgical anesthesia alone and in addition to general anesthesia and for postoperative analgesia. In addition to providing positive effects on the respiratory and cardiovascular systems and postoperative analgesia, various complications can be seen. In our study, we aimed to investigate the effect of epidural anesthesia, one of the regional anesthesia methods, on the optic nerve sheath diameter (OSKÇ) and whether this varies according to the applied volume. For the measurement of optic nerve sheath diameter, we performed serial measurements before and after epidural anesthesia with ultrasound. After obtaining the written consent of the ethics committee and patients, 63 patients aged between 18 and 65 years of age who were under ASA I-III physical status, undergoing epidural anesthesia in BAIBU Izzet Baysal Training and Research Hospital operating room, were included in the study. Patients were divided into two groups as double blind Low Volume (15 cc bupivacaine) and High Volume (20 cc bupivacaine) by randomized, prospective and closed envelope method. Patients entering the L3-L4 and L4-L5 range, and after the catheter was placed in the epidural catheter as bupivacaine anesthetic solution (0,5% and press Buster, Turkey) were given. We measured the change in time by measuring the OSCS of the patients, before the epidural (t0), immediately after the epidural (t1), 15th minute (t2), 30th minute (t3) and 60th minute (t4). There was no statistically significant difference between the groups in terms of demographic characteristics and clinical characteristics (p> 0.05). In the high volume group, the duration of anesthesia, the duration of surgery, the amount of fluid used were statistically significantly higher than the low volume group (p <0.05). The optic nerve sheath diameter variable appears to show a statistically significant change over time (p <0.001). In both groups, when the pre-epidural HSC value and post-epidural, 15-minute, 30-minute and 60-minute values were compared, the pre-epidural HSCT value was found to be statistically significantly lower (p <0.001). When compared with the 7th minute and 60th minute values, the OCDS value after epidural was statistically significantly higher. As a result, it was observed that the optic nerve sheath diameter increased after epidural anesthesia, this increase decreased over time but could not reach basal levels even after one hour.