The Effect of Neuromuscular Blockade on the Composite Variability Index (CVI) During Laryngoscopy

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT01450813
Recruitment Status : Completed
First Posted : October 12, 2011
Results First Posted : May 12, 2017
Last Update Posted : May 12, 2017
Information provided by (Responsible Party):
Medtronic - MITG

Brief Summary:

The Bispectral Index (BIS) monitor is used in many operating rooms to provide information to the anesthesiologist about a patient's level of consciousness. The Composite Variability Index (CVI) is a new index that may provide the anesthesiologist with more information about the condition of the patient. The CVI is a measure of the combined variability in BIS (bispectral index) and frontal electromyography (EMG) activity that may be useful in assessing the nociception/anti-nociception balance for patients under general anesthesia.The purpose of this study is to determine if a commonly used anesthetic drug (rocuronium) affects the CVI measurement differently with different doses. Rocuronium is a neuromuscular blocking agent (NMBA) routinely used during surgery. It is expected that the group given the highest dose of rocuronium will have diminished CVI values.

This study will randomize patients to one of four doses of rocuronium: no rocuronium, 0.2, 0.4, and 0.6 milligrams per kilo of body weight; the last dose is the standard amount for adults. It is expected that the group given the highest dose of rocuronium will have diminished CVI values. By including intermediate doses, information about the function of CVI in states of less than full muscle relaxation, or paralysis, will be obtained. This information is critically important for the development of the composite variability index, because during general anesthesia patients are usually maintained in a state of less than full paralysis. If the CVI response to stimulation in the intermediate groups is similar to the group receiving no rocuronium, the monitor may find wide clinical applicability. If the response is similar to the maximal rocuronium group, the index may only be reliable in states with no muscle relaxant, which will greatly limit clinical utility.

Condition or disease Intervention/treatment Phase
Anesthesia Neuromuscular Blockade Drug: Saline 0.06 ml/kg Drug: Rocuronium 0.2 mg/kg Drug: Rocuronium 0.4 mg/kg Drug: Rocuronium 0.6 mg/kg Not Applicable

Detailed Description:

Consented subjects randomized to one of four doses of rocuronium will be transported to the operating room and be connected to routine monitors that included a BIS (Covidien), M-Entropy sensor (GE Healthcare) and TOF (train of four) monitor. Following preoxygenation, general anesthesia will be induced with propofol and remifentanil using traditional syringe pumps. The induction doses given and subsequent infusion rates will be determined by utilizing pharmacokinetic (Pk) models (Marsh model for propofol, Minto model for remifentanil). Unconsciousness will be confirmed by performing the usual clinical assessments and by obtaining a BIS value between 40 and 50. Once the subject is unconsciousness, they will be given the assigned dose of rocuronium, after which the study anesthesiologist will perform a laryngoscopy. The anesthesiologist performing the laryngoscopy will not know what dose of rocuronium the subject received. Neuromuscular blockade (NMB) will be monitored by a train-of-four twitch monitor (TOF Watch-SX) at the adductor pollicis muscle (2 HZ, 50mAmp) every 15 seconds.

At three minutes after the rocuronium administration, a standardized 20-second laryngoscopy will be applied. The CVI, entropy, and hemodynamic responses (heart rate, blood pressure measurement each minute) and train-of-four measurements will be monitored for three minutes before and after the laryngoscopy.

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 80 participants
Allocation: Randomized
Intervention Model: Single Group Assignment
Masking: Double (Participant, Investigator)
Primary Purpose: Basic Science
Official Title: The Effect of Rocuronium on the Response of Composite Variability Index (CVI) to Laryngoscopy
Study Start Date : June 2009
Actual Primary Completion Date : December 2013
Actual Study Completion Date : December 2013

Resource links provided by the National Library of Medicine

Arm Intervention/treatment
Sham Comparator: Group 1
Saline 0.06 ml/kg
Drug: Saline 0.06 ml/kg
IV Infusion x1 prior to laryngoscopy
Other Name: Normal Saline

Active Comparator: Group 2
Rocuronium 0.2 mg/kg
Drug: Rocuronium 0.2 mg/kg
IV Infusion x1 prior to laryngoscopy
Other Name: Rocuronium bromide: Zemuron

Active Comparator: Group 3
Rocuronium 0.4 mg/kg
Drug: Rocuronium 0.4 mg/kg
IV Infusion x1 prior to laryngoscopy
Other Name: Rocuronium bromide: Zemuron

Active Comparator: Group 4
Rocuronium 0.6 mg/kg
Drug: Rocuronium 0.6 mg/kg
IV Infusion x1 prior to laryngoscopy
Other Name: Rocuronium bromide: Zemuron

Primary Outcome Measures :
  1. The Mean Difference in CVI Between Pre-laryngoscopy and Post-laryngoscopy for Each of the Four Rocuronium Groups [ Time Frame: Six minutes after the dose of rocuronium with laryngoscopy at 3 minutes after the study intervention ]

    The difference between the mean CVI in three minutes prior to laryngoscopy and three minutes following laryngoscopy reported as the mean change in CVI and the +/- 95% confidence interval for each group.

    The Composite Variability Index (CVI) scale is a logistic regression of three measures of processed electroencephalography (EEG) signals. These signals are Bispectral Index (BIS), the variability of electromyelogram (sEMG), and the variability of BIS (sBIS). The scale ranges from 0 to 100 where a lower CVI value represents a lower likelihood of intraoperative somatic responses, and a higher CVI value represents a higher likelihood of intraoperative somatic responses.

Secondary Outcome Measures :
  1. The Average CVI During the Maintenance Phase of Anesthesia for the Two Remifentanil Groups [ Time Frame: Maintenance Anesthesia ]
    Mean CVI from incision to propofol off reported as the mean CVI +/- 95% confidence interval for the two groups

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 75 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • American Society of Anesthesia (ASA) physical status class I or II.
  • Body mass index between 18 and 35 kg m-2.
  • No use of psychotropic or neuropsychiatric medications.
  • A airway assessment with no indication of a difficult intubation including a class I or II Mallampati airway and a mandible-to-hyoid distance of greater than three fingerbreadths.
  • Age between 18-75 years.

Exclusion Criteria:

  • Does not meet inclusion criteria.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT01450813

United States, Vermont
Fletcher Allen Health Care
Burlington, Vermont, United States, 05405
Sponsors and Collaborators
Medtronic - MITG
Principal Investigator: Donald M Mathews, MD University of Vermont

Responsible Party: Medtronic - MITG Identifier: NCT01450813     History of Changes
Other Study ID Numbers: COVMOPR0176
First Posted: October 12, 2011    Key Record Dates
Results First Posted: May 12, 2017
Last Update Posted: May 12, 2017
Last Verified: April 2017
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No
Plan Description: Data collected was for device algorithm development

Additional relevant MeSH terms:
Neuromuscular Nondepolarizing Agents
Neuromuscular Blocking Agents
Neuromuscular Agents
Peripheral Nervous System Agents
Physiological Effects of Drugs