Evaluating the Efficacy of Intravenous Atropine in Preventing Spinal Anaesthesia-Induced Hypotension in Lower Abdominal Surgery: A Controlled Study

Background: Spinal anesthesia-induced hypotension is a frequent complication that can lead to significant morbidity and even mortality if not promptly detected and addressed. This study evaluated the effect of intravenous atropine on the incidence of spinal anesthesia-induced hypotension in patients undergoing lower abdominal surgery. Methods: This prospective, randomized, double-blinded study recruited 130 adults with American Society of Anesthesiologists physical status I or II who underwent elective lower abdominal surgeries under spinal anesthesia at the Federal Teaching Hospital (formerly Federal Medical Centre) Lokoja in Kogi State, Nigeria. Participants were randomly assigned to receive either a placebo of 1ml of 0.9% saline or 1ml of 0.6mg intravenous atropine, 1 minute post induction of spinal anesthesia. Haemodynamic parameters including blood pressure, mean arterial pressure (MAP), and oxygen saturation were measured and recorded throughout the study. Statistical analysis was done using SPSS version 22. Student t-test was used to compare the change in mean arterial pressure between the two groups and chi square for categorical data. Probability value less than 0.05 was considered as statistically significant. Results: The incidence of hypotension was significantly lower in the atropine group (6.8%) compared to the normal saline group (19.6%; p = 0.041). Although fewer patients in the atropine group required multiple doses of ephedrine, this difference was not statistically significant (p = 0.152). Tachycardia occured more frequently in the atropine group (54.2% vs.14.3%, p < 0.001), and all cases of dry mucous membrane occurred in the atropine group (p = 0.004). Conclusion: Intravenous atropine (0.6mg) administered 1 minute after spinal anesthesia induction significantly reduces the incidence of spinal anesthesia-induced hypotension in patients undergoing lower abdominal surgery, but comparatively the severity was not clinically relevant.