The relationship between gestational week and QT dispersion in cesarean section patients undergoing spinal anaesthesia: A prospective study.

Background: Pregnancy affects the cardiovascular system, particularly the cardiac conduction system, thereby increasing the susceptibility of patients towards arrhythmia. QT interval results in ventricular arrhythmias, predominantly polymorphic ventricular tachycardia. The present study was planned to investigate the relationship between a gestational week and QT dispersion in cesarean section patients undergoing spinal anaesthesia.

Methods: The study included 40 patients between the ages of 18 and 45 who had no symptoms of anaemia and undergoing elective cesarean section. The patients were separated into two groups based on the gestational week as Group I <39 weeks and Group II ≥39 weeks. The patient was given a sitting position and the puncture site was cleansed with 10% povidone-iodine antiseptic solution. After placing a sterile drape on the patient, the subarachnoid space was punctured through an appropriate vertebral space (L3-L4 or L4-L5) using a pencil-point 25G spinal needle, followed by intrathecal injection of 12.5 mg (2.5 mL) 5% hyperbaric bupivacaine hydrochloride. Electrocardiographic (ECG) records were obtained both preoperatively and at 1, 5, and 10 minutes after spinal block, and the QT, QTc, QTd, and corrected QTd (QTcd) intervals were estimated using Bazett's formula.

Results: There was no significant difference between the two groups within the QT and QTc intervals. QTcd measured after post-operative was significantly higher in Group II (P = .007).

Conclusion: The results indicated that spinal anaesthesia may prolong the QTdc interval in patients with a gestational week of ≥39 weeks undergoing cesarean section.