Dosage of sugammadex according to the calculated lean body mass in obese female patients: time to reverse moderate neuromuscular blockade induced by rocuronium

Background: Sugammadex is a selective relaxant binding agent for antagonism of prolonged rocuronium-induced neuromuscular blockade. The recommended dose is 2 mg/kg. Based on the pharmacological characteristics of sugammadex in obese patients, the calculated lean body mass (CLBM) should be used to determine the dose to reverse moderate neuromuscular blockade induced by rocuronium. Objective: A study was undertaken to prove that sugammadex can be used according to CLBM to reverse moderate neuromuscular blockade in obese female patients. Methods: This is a prospective, non-randomised, observational study. Sugammadex was used at the end of bariatric surgery on obese patients with a body mass index > 32 kg/m2. The dose was calculated according to the lean body mass. Muscle blockade was assessed using train-of-four monitoring. Results: Twenty women were included in this study. All patients were female and ASA 2. The age of patients ranged between 20 and 50 years with a mean age of 35.74 (±10) years. The mean CLBM was 50 kg. The mean time from administration of sugammadex to reverse neuromuscular blockade from two responses of TOF to T4/T1 > 90% was 167.25 seconds (2.8 minutes) (60­285 seconds). Conclusion: It is concluded that the calculated lean body mass can be used to calculate the dose of sugammadex for obese female patients to reverse moderate neuromuscular blockade induced by rocuronium

Agent consumption with the Zeus® in the automated closed circuit anesthesia mode with O2/air mixtures.

BACKGROUND: Earlier software versions of the Zeus® (Lübeck, Dräger, Germany) failed to provide true closed circuit anesthesia (CCA) conditions. We examined whether the latest software (SW 4.03 MK 04672-00) achieves this goal. METHODS: In 8 ASA I-III patients, the CCA mode of the Zeus® was used to maintain the inspired O2 (FIO2) and end-expired sevoflurane % (FAsevo) at 50 and 1.8%, respectively. The fresh gas flow (FGF) of O2 and air and the sevoflurane injection rate (=Vinjsevo, mL liquid sevo/h) were videotaped from the control screen and entered offline into a spreadsheet. Cumulative sevoflurane usage during early wash-in (=0-1 min, CDsevo0-1), late wash-in (=1-5 min, CDsevo1-5), and maintenance (=5-60 min, CDsevo5-60) was calculated, and Vinjsevo between 1 and 60 min was compared with published uptake data. RESULTS: FAsevo reached 1.8% within 101 (23) sec. CDsevo0-1 was between 1.24 (0.03) and 3.01(0.25) mL (a range is provided because no absolute Vinjsevo values were displayed once Vinjsevo was > 100 mL/h, which occurred between 15 ± 2 and 46 ± 6 sec). CDsevo1-5 was 0.81 (0.37) mL, and CDsevo5-60 was 4.63 (0.94) mL. The Vinjsevo pattern between 1 and 60 min matched previously published uptake data. Brief high FGF periods were used to maintain the target FIO2, and to refill the reservoir bag after external pressure had been applied to the abdomen; subsequent "spikes" wasted 0.08-0.19 mL and 0.14-0.49 mL sevoflurane (1-3% and 3-9% of total agent usage between 1 and 60 min, respectively). CONCLUSION: Under the conditions specified, the Zeus® approaches CCA conditions so closely that further reductions in agent usage would have minimal economic significance.