Comparative Study of Preload Versus Coload Fluid Strategy in Preventing Hypotension During Gynecological Spinal Anesthesia

Background: Hypotension during spinal anesthesia is a frequent challenge in gynecological surgeries, requiring optimal fluid management to prevent adverse outcomes. Preload and coload strategies are commonly used to prevent this complication. Objective: This study aimed to compare the efficacy of preload versus coload fluid strategies in preventing hypotension during gynecological spinal anesthesia in a multi-center hospital setting. Methods: A randomized controlled trial was conducted at the Department of Anaesthesiology, Naogaon Medical College, Bangladesh, from July 2023 to June 2024. A total of 124 patients were enrolled, with 62 in each group: preload (500 ml infusion before surgery) and coload (saline with ephedrine during the procedure). Hypotensive sheik, systolic and diastolic blood pressure drops, the requirement for ephedrine rescue doses, and the total volume of fluid administered were recorded and analyzed. Results: In the preload group, hypotension occurred in 27% (17/62) of patients, with a mean systolic blood pressure drop of 25±5 mmHg (p-value = 0.03). The diastolic pressure drop was 18±4 mmHg (p-value = 0.02), and 5% (3/62) required ephedrine intervention. In the coload group, hypotension occurred in 37% (23/62), with a mean systolic blood pressure drop of 28±6 mmHg (p-value = 0.02) and a diastolic drop of 20±5 mmHg (p-value = 0.04). Ephedrine use was required in 15% (9/62) of cases. The total volume of fluid administered in the preload group was 550±50 ml, compared to 600±80 ml in the coload group (p-value = 0.04). The standard deviation of systolic blood pressure drop was significantly lower in the preload group, indicating more consistent outcomes (SD = 5 mmHg vs. 6 mmHg, p-value = 0.02). Conclusion: Preload fluid strategy is significantly more effective in preventing hypotension and maintaining more consistent blood pressure levels compared to coload, requiring fewer interventions.