Background and Goal of Study: The use of neuromuscular blocking agents has proved to be beneficial during general anesthesia. However, once the patient has been extubated, residual neuromuscular blockade becomes an undesirable and harmful effect1. Sugammadex has proved to be a useful tool against rocuronium-induced residual neuromuscular blockade.
The aim of this study is to demonstrate whether the use of intraoperative monitoring allows dose adjustment not only of rocuronium but also of sugammadex.
Materials and methods: We designed a randomized, single-center, double-blind trial. After approval by the ethics committee, 40 patients scheduled for elective laparoscopic cholecystectomy under general anesthesia were included.
Neuromuscular blockade (NMB) was monitored using ulnar nerve stimulation and acceleromyography. 
Patients received intravenous propofol, fentanyl and rocuronium (0.6 mg/kg) for induction followed by propofol and fentanyl maintenance anesthesia. Low doses of rocuronium (0.15 mg/Kg) were used to maintain NMB. Patients were randomly allocated to receive sugammadex from a syringe with 20 mg/ml (control group) or 10 mg/ml (study group). After the surgical closure, the anesthesiologist used on-label dosage of sugammadex (2 mg/kg) for the reversal of moderate NMB, assuming they were administrating the 20 mg/ml concentration in all cases. Those patients with profound NMB were excluded. Time to recovery of the train-of-four ratio (T4/T1) to 0.9 was recorded.
Statistical analysis was performed using Student's t-test, Fisher's test and linear regression. 
Results and discussion: Finally, a total of 34 patients were included (18 in control group and 16 in study group). No statistically significant differences between groups were found neither in demographic data nor in NMB. After sugammadex, T4/T1 recovered to 0.9 was 3,1 ±1,7 minutes in control group and 3,6 ±1,7 minutes in study group (p>0.05). No sugammadex adverse effects were observed.
Reversal of moderate NMB by sugammadex can be achieved with lower doses (1 mg/kg) than those recommended on-label by using intraoperative NMB monitoring. These doses do not increase the time needed to reverse NMB. The monitoring guided administration of sugammadex could reduce costs and allow a more extended use of the drug.
Conclusion: Reversal of moderate NMB by sugammadex can be achieved with lower doses than those recommended by using intraoperative NMB monitoring.

Sugammadex overdose? Randomized trial with 1 or 2 mg/kg of sugammadex to reverse moderate rocuronium-induced neuromuscular blockade