Prophylactic use of IV atropine for prevention of spinal anesthesia induced hypotension and bradycardia in elderly: a randomized controlled trial

Abstract

Background: Spinal anesthesia induced hypotension is common and hazardous in elderly patients. Reversal of the blunted reflexes of tachycardia following hypotension in elderly with atropine helps in prevention of spinal anesthesia induced hypotension in elderly. Methodology: In this randomized, double-blind, controlled trial forty ASA PS I to II patients undergoing urological surgeries were assigned to receive either IV normal saline (placebo) or IV atropine 0.6 mg one minute after the induction of spinal anesthesia. Heart rate (HR), mean arterial pressure (MAP), requirement for mephentermine or phenylephrine, and the side effects profile were studied intra/postoperatively for 6 hours. Results:The patients were comparable with respect to demographic profile, baseline hemodynamic parameters, and the duration of surgery. Compared to baseline, mean HR and MAP were significantly reduced in the placebo group most of the study times (p<0.05). The incidence of hypotension was high in placebo (60%) compared to the atropine group (5%). Thus, the requirement of mephentermine for the management of hypotension was significantly higher (p<0.001) in the placebo group (60%) than the atropine group (5%). Conclusion: Intravenous administration of atropine 0.6 mg, one min after the induction of spinal anesthesia in an elderly patient, is a safe and effective method in the prevention of spinal anesthesia induced hypotension and bradycardia.

Effects of prophylactic atropine in prevention of spinal anesthesia induced hypotension and bradycardia in geriatrics undergoing urological surgeries at a resource limited setting in Central Ethiopia, 2018; prospective cohort study.

“…Patients with Failed spinal, Heart block greater than rst degree, left bundle branch block, hypertension (SBP > 140 mmHg or DBP > 90 mmHg), preoperative tachycardia (HR > 120 bpm), β-adrenergic blockers, combinations of spinal block with other type of anesthesia, prior anticholinergic use within 2 hours before entering the operating room, supplementation of strong opioids [6] were excluded in the study.…”

“…Adding 10% nonresponse rate the total sample size was 76 (38 subjects to each group). The sample size was calculated based on a previous study in Nepal that showed the incidence of hypotension in atropine exposed and un-exposed groups to be 5% and 60% respectively [6].…”

“…Hypertension: greater than 20% increase from baseline BP [14]. Bradycardia: HR < 50 beats per minute [6].…”

“…Tachycardia: greater than 20% increase from baseline heart rate [6,15] Data collection procedures and tools Data was collected using a prepared checklist starting from immediate preoperative to 1 st intra/postoperative hour by four trained anesthetists. Mean arterial pressure and heart rate were recorded at 0 (baseline), 5 th , 10 th , 15 th , 20 th , 30 th , 40 th , 50 th , and 60 th minutes intraoperatively.…”

“…This may result from the blockade of cardioaccelerator sympathetic bers at T1 to T4, and due to the "reverse" of the Bainbridge reflex. To prevent this mechanism, prophylactic use of intravenous (IV) atropine might have importance [6].…”