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

Anesthesia Clinical Trial

Official title:

The Effect of Rocuronium on the Response of Composite Variability Index (CVI) to Laryngoscopy

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01450813
• Other study ID #: COVMOPR0176
• Status: Completed
• Phase: N/A
• First received: September 22, 2011
• Last updated: February 2, 2015
• Start date: September 2011
• Est. completion date: September 2014

Study information

• Verified date: February 2015
• Source: Medtronic - MITG
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Institutional Review Board
• Study type: Interventional

Clinical Trial Summary

The Bispectral Index monitor is used in many operating rooms to provide information to the anesthesiologist about a patient's level of consciousness. The Composite Variability Index, or Composite Variability Index (CVI), is a new index that may provide the anesthesiologist with more information about the condition of the patient. 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 muscle relaxant routinely used during surgery. It is expected that the group given the highest dose of rocuronium will have diminished CVI values.

Description:

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.

Subjects will receive propofol and remifentanil infusions during the case. These are commonly used medications for anesthesia. The subjects will also be randomized to two additional groups. One group will receive a remifentanil infusion of 2ng ml-1 and the other group will receive a 8ng ml-1 remifentanil infusion. Both doses are acceptable and often used during standard clinical care. The propofol infusion will be adjusted to keep the BIS number between 45-60. The anesthesiologist will not be able to see the CVI value. The times of certain intraoperative events, such as intubation and incision, will be recorded. All subjects will receive a morphine bolus (0.10-0.15 mg/kg) towards the end to reduce post-operative pain, as per standard clinical care. As the subject wakes up, time to eye opening and orientation will be recorded. The subject will rate their pain on a numerical pain scale and the quality of emergence will be assessed.

Upon arrival in the post anesthesia care unit (PACU), subjects will be asked to rate their pain again using the same pain scale. The pain score will be evaluated every 10 minutes for half an hour, then every hour until they are discharged from PACU.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 90
• Est. completion date: September 2014
• Est. primary completion date: August 2014
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 18 Years to 75 Years

Eligibility

Inclusion Criteria:

• Presence of ASA physical status class I or II. (This will exclude subjects with significant medical problems).

• 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.

Study Design

Allocation: Randomized, Intervention Model: Single Group Assignment, Masking: Double Blind (Subject, Investigator), Primary Purpose: Basic Science

Related Conditions & MeSH terms

• Anesthesia
• Neuromuscular Blockade

Intervention

Drug:
• Dose 1a
Rocuronium dose 0 mg/kg + Remifentanil infusion of 2ng ml-1
• Dose 2a
Rocuronium dose 0.2 mg/kg + Remifentanil infusion of 2ng ml-1
• Dose 3a
Rocuronium dose 0.4 mg/kg + Remifentanil infusion of 2ng ml-1
• Dose 4a
Rocuronium dose 0.6 mg/kg + Remifentanil infusion of 2ng ml-1
• Dose 1b
Rocuronium dose 0 mg/kg + Remifentanil infusion of 8ng ml-1
• Dose 2b
Rocuronium dose 0.2 mg/kg + Remifentanil infusion of 8ng ml-1
• Dose 3b
Rocuronium dose 0.4 mg/kg + Remifentanil infusion of 8ng ml-1
• Dose 4b
Rocuronium dose 0.6 mg/kg + Remifentanil infusion of 8ng ml-1

Locations

Country	Name	City	State
United States	Fletcher Allen Health Care	Burlington	Vermont

Sponsors (1)

Lead Sponsor	Collaborator
Medtronic - MITG

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	The difference between the mean CVI value prior to laryngoscopy to the maximal CVI reading following laryngoscopy.		The mean CVI value in the three minutes prior to laryngoscopy will be compared to the maximal CVI reading during the three minutes following laryngoscopy.	No
Secondary	The average CVI level during the maintenance phase of surgery.		The maintenance phase is defined as the time from surgical incision to the time that the propofol is turned off.	No