Effectiveness of Sugammadex in LMS Surgery

This study is comparing of rocuronium-sugammadex and succinylcholine during LMS surgery that is characterized by short operation time, required intense paralysis and ambulatory setting, has not been investigated.

Laser microlaryngeal surgery (LMS) requires brief and intense paralysis in the short operation time and the ambulatory setting.

The ideal muscle relaxant with rapid onset time, short duration of action and minimal side effects is not yet available.

Succinylcholine (SCC) is commonly used muscle relaxant for LMS because of its rapid onset time and short duration of action.

The use of SCC for tracheal intubation is usually followed by repeated small boluses or drip of SCC or small boluses of nondepolarizing muscle relaxants with intermediate duration.

As an alternative to SCC, the non-depolarizing neuromuscular blocking agent rocuronium can be used for LMS. The onset of rocuronium 1mg/kg is around 60s that is similar to SCC. However higher doses of rocuronium have a long duration of action; this is inappropriate in ambulatory surgery that requires rapid recovery of neuromuscular function and rapid turnover.

Sugammadex has recently been introduced as a selective relaxant-binding agent that allows for rapid reversal of rocuronium-induced neuromuscular blockade. Even profound neuromuscular block with rocuronium can be quickly antagonized with sugammadex.

After obtaining Institutional Review Board approval and written informed consent, 80 patients is enrolling in this study.

Patients is divided by two groups randomly as the Rocuronium-Sugammadex group(R-S group) and the Succinylcholine - Cisatracurium- Neostigmine group(S-C-N group) .

Anesthesia was induced with intravenous propofol 1.5-2.5 mg/kg, together with fentanyl1.5 mcg/kg After induction of anesthesia, neuromuscular monitoring is performed continuously at the adductor pollicis muscle with acceleromyography (TOF-Watch®).

Subsequently, in the R-S group, patients receive rocuronium 1mg/kg and in the S-C-N group, patients receive SCC 1mg/kg.

After T1 assessed as being zero by neuromuscular monitoring, endotracheal intubation is performed.

After endotracheal intubation, in the S-C-N group, cisatracurium 0.08mg/kg is injected and in the R-S group, the same volume of normal saline is injected.

Anesthesia is maintained with desflurane with air during the surgery. Additive dose of rocuronium 0.15mg/kg or SCC 10mg is given as necessary to ensure that neuromuscular blockade remains below T2 during surgery.

After the surgical procedure ends, patients receive sugammadex 2mg/kg in the R-S group, and pyridostigmine 0.2 mg/kg with atropine 10mcg/kg in the S-C-N group at the appearance of second TOF twitch (T2).

Patient will be assessed for the time to recovery of the TOF ratio to 0.9, surgical rating scale (1- extremely poor conditions, 2- poor conditions, 3- acceptable conditions, 4- good conditions, 5- optimal conditions), and anesthesia time.

Eligibility Criteria:
Inclusion Criteria:

* American Society of Anesthesiologist\[ASA\] class 1-3
* scheduled Laser microlaryngeal surgery under general anesthesia
* written informed consent

Exclusion Criteria:

* suspected difficult tracheal intubation
* disorder affecting neuromuscular blockade
* known or suspected significant renal dysfunction
* known or suspected severe hepatic dysfunction
* history of malignant hyperthermia
* allergy of opioids, neuromuscular blocking drugs or other medications used during general anesthesia
* contraindication to pyridostigmine and/or atropine
* pregnancy
* breast feeding
* body mass index \> 27kg/m2