Intermittent bolus versus Continuous infusions: Evaluating Neuromuscular blockers recovery

Background: The optimal mode of maintaining intraoperative neuromuscular blockade remains uncertain, and no randomized comparison has been reported from Pakistan. We compared intermittent bolts and continuous infusion of atracurium for time to neuromuscular recovery and total drug requirement. Methods: In this single-Centre, parallel-group randomised controlled trial (Doctors Hospital and Medical Center, Lahore; 15 February to 14 August 2024), 80 adults aged 18–60 years, ASA physical status I–II, scheduled for elective surgery under general anesthesia were randomised to atracurium 0.1 mg/kg every 30 min (intermittent bolus, n = 40) or atracurium 0.2 mg/kg/h (continuous infusion, n = 40) after a 0.5 mg/kg intubating dose. The primary outcome was time from the last bolus or cessation of infusion to a train-of-four (TOF) ratio ≥0.8 at the adductor pollicis; the secondary outcome was total intraoperative atracurium dose. Groups were compared with independent-samples t tests. Results: All 80 randomized patients were analysed. Mean (SD) recovery time was 30.75 (3.99) min with intermittent bolus and 49.73 (4.20) min with continuous infusion (mean difference 18.98 min; 95% CI 17.16 to 20.80; P < 0.001). Total atracurium dose was 51.98 (4.40) mg and 80.60 (5.40) mg, respectively (mean difference 28.62 mg; 95% CI 26.43 to 30.81; P < 0.001). The direction and magnitude of both differences were consistent across age, sex, body mass index, ASA status and surgical specialty. Conclusions: In ASA I–II adults undergoing elective surgery, intermittent bolus atracurium was associated with faster neuromuscular recovery and a lower total dose than continuous infusion.