Repeat dosing of rocuronium 1.2 mg kg−1 after reversal of neuromuscular block by sugammadex 4.0 mg kg−1 in anaesthetized healthy volunteers: a modelling-based pilot study

Re-intubation and re-operation may occasionally be required after neuromuscular block (NMB) reversal. This study evaluated block onset times of a second dose of rocuronium (1.2 mg kg−1) after sugammadex reversal of rocuronium 0.6 mg kg−1. In this open-label study of healthy anaesthetized volunteers, subjects received rocuronium 0.6 mg kg−1, were antagonized at 1–2 post-tetanic counts with sugammadex 4.0 mg kg−1, and received rocuronium 1.2 mg kg−1 at 5, 7.5, 10, 15, 20, 22.5, 25, 27.5, 30, 45, or 60 min after sugammadex. Spontaneous recovery occurred after repeat rocuronium dose. Primary endpoints were the onset time of maximal block (time to lowest T1 value reached) and the clinical duration of block (until T1=25%) after repeat rocuronium dose. Sixteen subjects were included. For subjects receiving rocuronium 1.2 mg kg−1 5 min after sugammadex (n=6), mean (sd) onset time (to T1=0) was 3.06 (0.97) min; range, 1.92–4.72 min. For repeat dose time points ≥25 min (n=5), mean onset was faster (1.73 min) than for repeat doses