Comparison Neuromuscular Blockade Monitors

NCT05006807 | Completed Results

• 1 other identifier: STUDY00001561
• Study Type: observational
• Target: 51
• Locations: 1 country
• Sites: 1

Brief Summary

The overall objective of this research is to evaluate different laboratory-built and commercially available sensors used to measure the effects of neuromuscular blocking drugs on neuromuscular function during surgery, by measuring evoked thumb twitch response to ulnar nerve stimulation (also known as "twitch monitoring"). The specific aim is to compare mechanomyography, which is the "gold standard" laboratory measurement to assess neuromuscular blockade, to the sensors used in commercially available neuromuscular blockade monitors, such as acceleromyography and electromyography. The study endpoints are the train-of-four count (TOFC), the ratio of the height of the 4th twitch to the height of the 1st twitch (train-of-four ratio, TOFR), and the post tetanic count (PTC). The mechanomyography devices have been constructed in our laboratory and are not commercially available.

Conditions

Neuromuscular Blockade

Outcome Measures

Primary Outcomes (1)

• Train-of-four Ratio

  Determine evoked thumb twitch response to ulnar nerve train-of-four stimulation then determine the ratio of the amplitude of the fourth twitch divided by the first twitch, referred to as the train-of-four ratio. The train-of-four ratio is expected to be 1.0 in the absence of neuromuscular blocking drugs. The range of possible train-of-four ratios is 0-1.6. Results that deviate from a train-of-four ratio of 1.0 represent inaccuracy of the measurement.

  Procedure (from the induction of anesthesia until emergence of anesthesia)

Study Arms (1)

Twitch Monitoring

Patients undergoing surgery with general anesthesia requiring neuromuscular blockade.

Device: Mechanomyograph Twitch Monitor; Device: Stimpod Twitch Monitor; Device: TetraGraph Twitch Monitor; Device: TwitchView Twitch Monitor; Device: Nihon Kohden Twitch Monitor; Other: Palpation of twitch count

Interventions

Mechanomyograph Twitch Monitor DEVICE

Measurement of train-of-four count and ratio and post tetanic count

Twitch Monitoring

Stimpod Twitch Monitor DEVICE

Measurement of train-of-four count and ratio and post tetanic count

Twitch Monitoring

TetraGraph Twitch Monitor DEVICE

Measurement of train-of-four count and ratio and post titanic count

Twitch Monitoring

TwitchView Twitch Monitor DEVICE

Measurement of train-of-four count and ratio and post tetanic count

Twitch Monitoring

Nihon Kohden Twitch Monitor DEVICE

Measurement of train-of-four count and ratio and post tetanic count

Twitch Monitoring

Palpation of twitch count OTHER

The train-of-four count is determined by manual palpation of the evoked twitch response

Twitch Monitoring

Eligibility Criteria

• Age: 18 Years - 100 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Patients 18 years of age or older undergoing anesthesia that requires neuromuscular blocking drugs at University of Washington Medical Center.

You may qualify if:

• years of age or greater
• Undergoing anesthesia that requires neuromuscular blocking drugs

You may not qualify if:

• Less than 18 years of age
• Undergoing anesthesia that does not require neuromuscular blocking drugs
• Undergoing a procedure in which access to one or both arms is limited
• Anatomical abnormalities of the hands or arms that preclude twitch monitoring with ulnar nerve stimulation and evoked thumb twitch response

Sponsors & Collaborators

• University of Washington: lead

Study Sites (1)

University of Washington Medical Center

Seattle, Washington, 98195, United States

Location

Related Publications (2)

• Wedemeyer Z, Bowdle A, Jelacic S, Silliman W, Michaelsen KE. The effect of excessive noise rejection, noise filtering and twitch threshold on mechanomyograph twitch measurements. Anaesth Crit Care Pain Med. 2026 May;45(3):101780. doi: 10.1016/j.accpm.2026.101780. Epub 2026 Mar 3.

  PMID: 41786028 DERIVED

• Wedemeyer Z, Jelacic S, Michaelsen K, Silliman W, Togashi K, Bowdle A. Comparative performance of stimpod electromyography with mechanomyography for quantitative neuromuscular blockade monitoring. J Clin Monit Comput. 2024 Feb;38(1):205-212. doi: 10.1007/s10877-023-01087-1. Epub 2023 Oct 13.

  PMID: 37831378 DERIVED

Limitations and Caveats

All data were collected in the absence of neuromuscular blocking drugs. This was also an important strength because it allowed the collection of a very large number of train-of-four ratio measurements when the true train-of-four ratio was know to be 1.0. an argument can be made that the performance of the monitors should be the best possible in the absence of neuromuscular blocking drugs since the signals produced by ulnar nerve stimulation are at the maximum.

Results Point of Contact

• Title: Andrew Bowdle MD, PhD, FASE
• Organization: University of Washington

bowdle@protonmail.com

2069790477

Study Officials

• T. Andrew Bowdle, MD, PhD

  University of Washington

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: No
• Restrictive Agreement: No

Study Design

• Study Type: observational
• Observational Model: CASE ONLY
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor, School of Medicine

Study Record Dates

• First Submitted: August 10, 2021
• First Posted: August 16, 2021
• Study Start: February 1, 2022
• Primary Completion: December 1, 2024
• Study Completion: December 1, 2024
• Last Updated: July 8, 2026
• Results First Posted: July 8, 2026

Record last verified: 2024-12

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)