Determination of Target of Adequate Partial Neuromuscular Blockade for Electrophysiologic Monitoring During Microvascular Decompression Surgery

Samsung Medical Center

Status: Completed

Conditions: Microvascular Decompression; Neuromuscular Blockade; Hemifacial Spasm

Treatments: Other: TOF count-guided partial NMB; Other: T1/Tc guided partial NMB

Study type: Interventional

Funder types: Other

Identifiers

NCT01613781

2012-05-051

Details and patient eligibility

About

There have been reports of monitoring LSR during MVD surgery helps predicting the clinical outcome of MVD. However, there have been no evidence of which degree of partial neuromuscular blockade should be performed during LSR monitoring under sevoflurane anesthesia. Therefore, the investigators performed a randomized controlled trial to evaluate the effect of different degree of partial neuromuscular blockade on the LSR monitoring for MVD surgery.

Full description

Hemifacial spasm develops by vascular compression of facial nerve at the root exit zone from brain stem. Microvascular decompression (MVD) is known for its curative treatment. Lateral spread response (LSR) is a kind of pathologic electromyographic (EMG) wave form which develops when facial nerve is compressed by vessel. There have been reports of monitoring LSR during MVD surgery helps predicting the clinical outcome of MVD.

As neuromuscular blockade during LSR monitoring decreases the amplitude of EMG, partial neuromuscular blockade is usually maintained during general anesthesia for MVD. However, there have been no evidence of which degree of partial neuromuscular blockade should be performed during LSR monitoring under sevoflurane anesthesia. Therefore, the investigators performed a randomized controlled trial to evaluate the effect of different degree of partial neuromuscular blockade on the LSR monitoring for MVD surgery.

Enrollment: 61 patients

Sex: All

Ages: 20 to 70 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Those who undergo microvascular decompression with sevoflurane anesthesia by diagnosis of hemifacial spasm in our institution

Exclusion criteria

• Patients were excluded from the study if they had any of following: severe cardiopulmonary disorder with hemodynamic unstability (pulmonary hypertension, cardiomyopathy, mechanical ventilation, American Society of Anesthesiologists physical status III or more), severe hepatic or renal disease.
• Those who can not undergo MEP monitoring due to central or peripheral neuromuscular disease, e.g. cerebral palsy, myasthenia gravis, acute spinal injury, neurologic shock

Trial design

61 participants in 2 patient groups

T1/Tc amplitude-guided group

Active Comparator group

Description:

Using partial neuromuscular blockade to maintain T1/Tc amplitude of 50%, T1/Tc amplitude measured by the neuromuscular transmission module (NMT)

Treatment:

Other: T1/Tc guided partial NMB

TOF count-guided group

Active Comparator group

Description:

Using partial neuromuscular blockade to maintain train-of-four response of two, TOF response measured by the neuromuscular transmission module (NMT module)

Treatment:

Other: TOF count-guided partial NMB