Electromyographic Monitoring and Postoperative Recovery

December 6, 2021 updated by: NorthShore University HealthSystem
Residual neuromuscular blockade (weakness) is a common occurrence in the postanesthesia care unit when muscle relaxant drugs have been used in the operating room. The only method of reliably detecting residual neuromuscular blockade is through the use of quantitative neuromuscular monitors. These devices measure and quantify the degree of muscle weakness and display the results on a screen. When using train-of-four (TOF) nerve stimulation, the ratio of the fourth muscle contraction (twitch) to the first twitch will be displayed; when this ratio is 90% (or 0.9) or greater, full recovery of muscle strength is present, and the endotracheal tube can be safely removed. At the present time, there is only one commercially available quantitative monitor produced in the United States -the TOF-Watch. The TOF-Watch is not used by many clinicians because it requires experience to obtain accurate results, is expensive, and is subject to interference by factors in the operating room. The aim of this investigation is to examine a new quantitative monitor (the TetraGraph, an electromyography (EMG) device) in the clinical setting. Patients will be randomized to receive either electromyography monitoring (EMG group-using the TetraGraph) or qualitative peripheral nerve stimulator monitoring (PNS group-the standard type of neuromuscular monitoring used at NorthShore University HealthSystem). The primary endpoint of the investigation is the incidence of postoperative residual blockade (defined as a TOF ratio < 0.9 with TOF-Watch, the current "gold standard quantitative monitor). Secondary endpoints include a variety of standard clinical recovery variables.

Study Overview

Detailed Description

Although anesthesiologists recognize that residual neuromuscular block can adversely affect postoperative recovery, a high percentage of patients continue to arrive in the PACU with TOF ratios < 0.9. An important reason this problem occurs is that anesthesiologists rarely use quantitative neuromuscular monitoring in the operating room. In current anesthesia practices, clinicians typically use standard peripheral nerve stimulators (qualitative neuromuscular monitors) and / or clinical tests of muscle strength to detect residual muscle weakness at the end of surgical procedures. Qualitative nerve stimulators/monitors are routinely used in the operating rooms; TOF electrical stimuli are applied to a peripheral nerve, and the contractions of the innervated muscle observed. However, visual or tactile assessment of TOF stimulation using these monitors is only effective in detecting profound levels of muscle weakness (TOF ratios < 0.4) Therefore, qualitative nerve stimulators are unable to reliably detect clinically relevant neuromuscular block (TOF ratios of 0.5-0.9). Clinical assessment of patients for signs of muscle weakness (head-lift, hand squeeze) is also an insensitive method of detecting residual neuromuscular block, since many patients can perform these tests with TOF ratios as low as 0.5.

In order for clinicians to reliably exclude residual neuromuscular blockade, quantitative neuromuscular monitoring should be used. At the present time, only one stand-alone quantitative monitor has been produced for clinical use, the TOF-Watch (Blue Star Enterprises, Chanhassen, Minnesota-no longer manufactured). This technology (acceleromyography (AMG)) uses a piezoelectric crystal to sense the acceleration of muscle contractions, and converts this data into a displayed TOF ratio (0-100%). Although the use of the TOF-Watch has been demonstrated to reduce the risk of residual blockade, the routine application of this monitor by clinicians has been limited by a number of factors, related to complexity of use in the operating room.. There is an urgent need for an easy-to-use and accurate quantitative neuromuscular monitor in the clinical setting. Recently, a new device has been developed that uses electromyography (EMG) technology to assess recovery of muscle function in the clinical setting (the TetraGraph). This EMG device measures electrical activity (compound muscle action potentials) following nerve stimulation (usually at the thenar eminence after ulnar or median nerve stimulation). When TOF stimuli are provided, this data is then converted to a measurable TOF ratio (from 0-1.0 or 0-100%). In a study completed at NorthShore University HealthSystem, the investigators compared the applicability (ease of use, equipment need, etc.), repeatability (precision or internal consistency), and performance (agreement with established standard, bias) of this EMG technology to the TOF-Watch (the current clinical "gold standard" quantitative neuromuscular monitor). The subsequent analysis suggested that EMG monitoring accurately measures onset and recovery of neuromuscular function in the operating room.

The use of quantitative neuromuscular monitoring in the operating room should allow for more rational management of dosing and reversal of NMBAs. Furthermore, if incomplete neuromuscular recovery is detected at the end of a surgical procedure, tracheal extubation can be delayed until full recovery of muscle strength has occurred. Therefore, fewer patients should leave the operating room with muscle weakness, and the risks/complications of residual blockade in the PACU reduced. The aim of this clinical investigation is to determine whether EMG monitoring in the operating room reduces the incidence of postoperative residual blockade (measured at the time of tracheal extubation and on arrival to the PACU). During the PACU admission, patients will also be assessed for potential complications related to incomplete neuromuscular recovery (signs and symptoms of muscle weakness, episodes of hypoxemia and airway obstruction, prolonged PACU length of stay). Patients will be randomized to receive either electromyography monitoring (EMG group-TetraGraph) or qualitative peripheral nerve stimulator monitoring (PNS group) in the operating room. The primary endpoint is the incidence of postoperative residual block (defined as a TOF ratio < 0.9 with the TOF-Watch monitor). Secondary endpoints include a variety of clinical recovery variables listed below.

Study Type

Interventional

Enrollment (Actual)

130

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • Illinois
      • Evanston, Illinois, United States, 60201
        • NorthShore University HealthSystem

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 90 years (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria: American Society of Anesthesiologists Status I - III patients undergoing surgery requiring neuromuscular blockade

-

Exclusion Criteria:

presence of an underlying neuromuscular disease; use of drugs known to interfere with neuromuscular transmission (antiseizure medications, anticholinesterases, magnesium sulfate); renal insufficiency (serum creatinine > 1.8 mg/dL) or renal failure.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Prevention
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Single

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Tetragraph
Patients will be randomized to receive quantitative monitoring in the operating room. Neuromuscular management will be guided by information provided by the monitor
Neuromuscular monitoring will be guided by information provided by the Tetragraph
Active Comparator: Qualitative monitoring
The screen of the Tetragraph will be covered so that information is not provided to the clinician. The monitor will therefore function as a standard peripheral nerve monitor (clinicians will only observe the response to nerve stimulation)
Neuromuscular monitoring will be guided by information provided by the Tetragraph

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Incidence of postoperative residual neuromuscular blockade
Time Frame: 15 minutes
the percentage of patients admitted to the postanesthesia care unit with train-of-four ratios < 0.9 will be determined
15 minutes

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Incidence of hypoxemic events in the postanesthesia care unit
Time Frame: 60 minutes
The number of patients with episodes of oxygen saturations < 95% will be determined
60 minutes
Airway obstruction
Time Frame: 60 minutes
the number of episodes of clinically-observed airway obstruction will be determined
60 minutes
Symptoms of muscle weakness
Time Frame: 15 minutes after admission to the postanesthesia care unit
The number of symptoms of muscle weakness measured 15 minutes after admission to the postanesthesia care unit will be determined
15 minutes after admission to the postanesthesia care unit

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

March 26, 2019

Primary Completion (Actual)

October 20, 2020

Study Completion (Actual)

October 20, 2020

Study Registration Dates

First Submitted

March 25, 2019

First Submitted That Met QC Criteria

March 25, 2019

First Posted (Actual)

March 27, 2019

Study Record Updates

Last Update Posted (Actual)

December 21, 2021

Last Update Submitted That Met QC Criteria

December 6, 2021

Last Verified

February 1, 2020

More Information

Terms related to this study

Other Study ID Numbers

  • EH13-032

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

Yes

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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