Reversal of Residual Neuromuscular Blockade at Train-of-four Ratio 0.3 With Sugammadex and Neostigmine

Dose Finding Study for Reversal of Vecuronium-induced Neuromuscular Blockade at Train-of-four Ratio 0.3 With Sugammadex and Neostigmine

The aim of this study is to estimate the optimal dose of sugammadex and neostigmine reversal of a vecuronium-induced residual neuromuscular block at train-of-four ratio 0.3.

Sugammadex is a modified γ-cyclodextrin compound that reverses the neuromuscular blockade produced by steroidal nondepolarizing muscle relaxants such as rocuronium,vecuronium and pipecuronium by encapsulating them, making them unavailable to interact with the nicotinic acetylcholine receptors at the neuromuscular junction.However, residual neuromuscular blocks between reappearance of T4 and train-of-four ratio (TOFR)=0.5 are more frequent in clinical practice compared with profound or deep blocks and have not been investigated for sugammadex previously.

Unlike neostigmine, sugammadex is efficacious in reversing profound (no responses to either train-of-four (TOF) or posttetanic count stimulation) or deep (posttetanic count of 1 or 2) neuromuscular block (NMB) in doses of 16 and 4 mg/kg, respectively. However, shallow neuromuscular blocks are more frequent in clinical practice compared with profound or deep blocks and have not been investigated for sugammadex previously.

Inclusion Criteria:

• 1 age of 18 to 65 yr,
• 2 body mass index 18.5 to 25.0 kg/m2,
• 3 American Society of Anesthesiologists physical status I to III
• 4 scheduled for elective surgery with an expected duration of at least 60min under general anesthesia with intubation of the trachea or laryngeal mask
• 5 patients having given informed consent to the study

Exclusion Criteria:

• 1 patients who had participated in another clinical trial within 1 month
• 2 Patients with suspected difficult airway, bronchial asthma, chronic obstructive pulmonary disease
• 3 known neuromuscular disease
• 4 suspected malignant hyperthermia
• 5 hepatic or renal dysfunction
• 6 glaucoma
• 7 allergy to the medication that used in this trial
• 8 taking medicaments that might influence the effect of NMB agents
• 9 pregnant, or breastfeeding state
• 10 taking medication known to alter the effect of neuromuscular blocking agents( toremifene .etc)