Clinical Trial: Fade Upon TOF Stimulation Induced by Succinylcholine
Study Status: Recruiting
Recruit Status: Recruiting
Study Type: Interventional
Official Title: Characterizing Fade Upon Train-of Four Stimulation During Onset and Offset of Neuromuscular Block Produced by Succinlycholine
Brief Summary: Muscle relaxants are medications used during surgery to facilitate surgical access. The effect of the muscle relaxant medications is measured by stimulation a motor nerve and measuring the force of the resultant muscle contraction. Based on the mechanism of action, two kinds of muscle relaxants are described. First a nondepolarizing muscle relaxant and the second kind is the depolarizing muscle relaxant. These two kinds of muscle relaxants can be distinguished by rapidly stimulating the nerve 4 times over 2 seconds (Train of four or TOF). The nondepolarizing muscle relaxants produce fade ie successive muscle contractions are less forceful than the preceding ones. Whereas the depolarizing muscle relaxants are generally believed to produce four contractions of equal strength. However, there is some indication that this may not be entirely correct. There is evidence that depolarizing muscle relaxants also may produce fade. The investigators are conducting the following study to determine if indeed depolarizing muscle relaxants produce fade. The investigators would also like to characterize the fade ie differences during onset and offset of the block and the effect of the dose on the degree on the fade.
Detailed Summary:
Muscle relaxants are frequently employed during anesthesia. These medications may be employed to facilitate tracheal intubation, mechanical ventilation or to allow better surgical access. All muscle relaxants act at the neuromuscular junction. Based on the mechanism of action, two kinds of muscle relaxants have been defined1. Nondepolarizing muscle relaxants are competitive antagonists of the neurotransmitter acetylcholine (Ach) at the neuromuscular junction. The second kind of muscle relaxant is the depolarizing muscle relaxant and succinylcholine is the only muscle relaxant in this class that is clinically used. The mechanism of action of succinylcholine is less clear. Succinylcholine appears to mimic the actions of acetylcholine but results in a longer duration of depolarization of the post synaptic membrane1.
The degree of muscle relaxation produced by these muscle relaxants is measured by stimulating a motor nerve and measuring either the force of the muscle contraction produced or its compound muscle action potential (CMAP). As the muscle relaxation increases, the force of muscle contraction or the amplitude of the electromyogram (EMG) is correspondingly reduced.
On occasion, to measure the degree of muscle weakness or paralysis caused by a muscle relaxant, instead of a single stimulus, trains of stimuli are applied2. One method of repetitive stimulation is to apply four stimuli over a two second period. This method of nerve stimulation is called Train-of-Four (TOF). When this form nerve stimulation (TOF) is applied to patients who have been given nondepolarizing muscle relaxants -there is fade. Fade means that the force of successive muscle contractions is less than the preceding contraction3. The second contraction is less than the first, the third less than the second and so on. The degree of fade appears to have
Sponsor: University of Toledo Health Science Campus
Current Primary Outcome: Fade on train of four stimulation [ Time Frame: for the duration of the effect of succinylcholine generally expected to be 6-10 minutes ]
Original Primary Outcome: Same as current
Current Secondary Outcome:
Original Secondary Outcome:
Information By: University of Toledo Health Science Campus
Dates:
Date Received: April 14, 2015
Date Started: April 2015
Date Completion: May 2017
Last Updated: September 21, 2016
Last Verified: September 2016
