Evaluation of intracranial pressure during electroconvulsive therapy

Purpose: ECT is an effective method that has been used for many years in the treatment of psychiatric diseases and is currently applied under general anesthesia. In this study, the effects of ECT on intracranial pressure were evaluated by measuring the diameter of the optic nerve sheath (ONSD) by ultrasonography. It is aimed to determine the possible side effects of ECT and the points to be considered in its application and patient selection. Material and Methods: In our prospective, observational study, 39 ASA I-II-III patients over the age of 18 who required ECT for various psychiatric problems were included. Patients were monitored with ECG, pulse oximetry, non-invasive blood pressure measurement and the values obtained were recorded. Age, gender, weight, height, psychiatric diagnosis and comorbidities were also recorded. All patients underwent standard general anesthesia required for ECT (3 mg/kg sodium thiopental for induction of anesthesia, followed by 0.5 mg/kg rocuronium for muscle relaxation, followed by 100% oxygen and ventilation with a face mask). Measurement of ONSD by ultrasonography was performed by a single physician using a high frequency linear probe in the range of 4-13 MHz. With the patient in supine position, one eye was closed, the eyelid was covered with ultrasound gel and horizantal and sagittal measurements were made with a linear probe without pressure on the eyeball and mean values were calculated. Data on ONSD measurement and hemodynamic changes were recorded four times: before anesthesia, after induction of anesthesia, after ECT (postictal) and in the recovery unit, and the data obtained were statistically evaluated. Results: In 39 patients included in our study, the ONSD measurements performed before induction of anesthesia were accepted as baseline values. When the change in optic nerve sheath diameter measurements over time was analyzed, the measurement 3 (postictal) value was found to be statistically significantly higher than the measurement 1 (preinduction), measurement 2 (postinduction) and measurement 4 (recovery) ONSD values (p<0.001). The mean value of preinduction ONSD was 4.89 ± 0.33 mm and the mean value of postictal ONSD was 5.47 ± 0.40 mm and it was observed that ECT caused a change intracranial pressure. The mean ONSD in the recovery period was measured half an hour after ECT and was found to be 4.96 ± 0.38. With this measurement, it was observed that the increase in ICP continued but approached the baseline value. When the relationship between comorbidities and ONSD values was analyzed, all ONSD measurement values were statistically significantly higher in patients with hypertension (p=0.001). Conclusion: Ultrasonography measurements of the ONSD showed that ECT changed the intracranial pressure, but this was short-lived and the intracranial pressure returned to baseline values during the recovery period. We believe that there is a need for more comprehensive, prospective studies investigating the impact of ONSD measurement during ECT on cerebral physiology and clinical outcomes, especially in the presence of comorbidities such as hypertension and obesity. Key Words: ECT, optic nerve sheath diameter, intracranial pressure, ultrasound