Evaluating the Use of 0.5 and 0.75 MAC Desflurane in Patients Undergoing Spinal Surgery

Evaluating the Use of Desflurane in Patients Undergoing Spinal Surgery: A Randomized Controlled Trial Using 0.5 and 0.75 MAC Desflurane

Background: Somatosensory- (SSEPs) and motor-evoked potentials (MEPs) are commonly used as an intraoperative neurophysiologic monitoring tool to detect aberrations to the spinal cord integrity during spinal surgery. Inhalational anaesthetic agents have a significant influence on evoked potentials by suppressing the amplitude and prolonging the latency. Evidences suggest that total intravenous anaesthesia (TIVA) is superior to inhalation anaesthesia for neuromonitoring in spinal surgery, and support the use of up to 0.5 minimum alveolar concentration (MAC) of inhalational anaesthetic agents in these procedures.

Methods: Patients undergoing spinal surgeries will be prospectively recruited and be induced with TIVA at baseline of the evoked potentials. They will be randomized to receive balance anaesthesia with A) Desflurane MAC 0.5+remifentanil, or B) Desflurane MAC 0.75+remifentanil until the end of surgery. Influence of 1.0 MAC desflurane on the evoked potentials after the completion of surgery will also be studied.

Desired Results: Endpoints include the changes to the amplitude and latency of SSEPs and MEPs with 0.5 and 0.75 MAC desflurane. The findings will indicate the safety of desflurane at the studied concentrations for spinal surgeries, and substantial savings with the use of desflurane instead of TIVA.

Study Overview

• Status: Recruiting
• Conditions: Anesthesia
• Intervention / Treatment: Drug: 0.75 MAC desflurane; Drug: 1.0 MAC desflurane; Drug: 0.5 MAC desflurane

Detailed Description

Recording of Evoked Potentials characteristics:

The following characteristics of the evoked potential signals will be recorded:

• Amplitude: Size of the response, measured in microvolts (μV)
• Latency: Speed of the response, measured in milliseconds (ms)
• Morphology: Appearance of the response - Simple/Complex wave shape Baseline evoked potentials will be recorded at various points of surgery.

Anaesthesia variables:

At the time of recording of evoked potentials:

- Intraoperative temperature, blood pressure, ETCO2, anaesthesia depth - bispectral index monitoring (BIS), remifentanil TCI, MAC of desflurane, Train of Four, volume of propofol and remifentanil until randomization, total volume of desflurane and remifentanil used, anaesthetic medications used, FiO2, SpO2

Patient characteristics:

- Age, gender, race, weight, BMI, medications used, haematocrit, preop blood glucose (for Diabetics)

Safety considerations:

'Recommended standards for intraoperative monitoring of somatosensory evoked potentials', Guideline 11B of the American Clinical Neurophysiology Society (2009) and 'Intraoperative motor evoked potential monitoring - A position statement by the American Society of Neurophysiological Monitoring' will form the basis of the safety aspects of the study.

Conduct of Anaesthesia:

• The induction of anaesthesia will be achieved using targeted propofol and remifentanil infusions (TIVA). Muscle relaxants atracurium, rocuronium or suxamethonium will be used to facilitate intubation.
• Anaesthesia will be maintained on TIVA until the patient has recovered from muscle relaxant. Baseline characteristics (BC1) of the evoked potentials in TIVA will be obtained at this stage.
• Once the BC1 has been obtained, the patients will be randomized to two groups:

Group A- Anaesthesia maintained with 0.5 MAC desflurane/remifentanil infusion Group B- Anaesthesia maintained with 0.75MAC desflurane/remifentanil infusion

• Baseline characteristics 2 (BC2) will be obtained and the decision to proceed with 0.5 or 0.75 MAC desflurane made.
• On completion of the neuromonitoring phase of surgery, as defined by completion of instrumentation and start of closure, all patients in Group A and B will be maintained with 1.0 MAC desflurane with remifentanil infusion. Baseline characteristics 3 (BC3) will be recorded at this stage.
• The remifentanil infusion will be titrated at various stages of surgery to maintain a stable BIS and will also be based on haemodynamic variables.

All patients will get additional analgesics and antiemetics as deemed necessary. Post-operative recovery will follow the standard industry norms.

• Study Type: Interventional
• Enrollment (Anticipated): 100
• Phase: Phase 4

Contacts and Locations

• Study Contact: Name: Seok Hwee Koo, PhD; Phone Number: +6568504929; Email: seok_hwee_koo@cgh.com.sg

Study Locations

• Singapore
  • Singapore, Singapore, 529889
    • Recruiting
    • Changi General Hospital
    • Sub-Investigator: Rajkumar Chandran
    • Contact: Lay Hwa Yew
    • Sub-Investigator: Prit Anand Singh
    • Sub-Investigator: Shree Kumar Dinesh
    • Sub-Investigator: Seok Hwee Koo
    • Sub-Investigator: Wee Lim Loo
    • Sub-Investigator: Terry Teo

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 19 years to 97 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Patients aged ≥ 21 years old, scheduled for spinal surgery.
• Patients who require SSEP/MEP and with no neurological deficits.
• Patients of American Society of Anesthesiologist I-III physical status.
• Consenting patients.
• Elective procedures.

Exclusion Criteria:

• Patients with sensory or motor deficits preoperatively.
• Patients with significant cardiovascular and/or respiratory disease.
• Emergency procedures.
• Cord injury secondary to trauma.
• Non-consenting patients.
• Category A patients (Prisoners).
• Patients with previous stroke.
• Patients with Hep C, HIV.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: 0.75 MAC desflurane; The effects of 0.75 MAC desflurane on the amplitude and latency of evoked potentials in spinal surgeries will be examined.	Drug: 0.75 MAC desflurane; Following induction of anesthesia by propofol, the patients will be maintained on 0.75 MAC desflurane with remifentanil infusion during spinal surgery.; Other Names: 0.75 MAC desflurane (Suprane); Drug: 1.0 MAC desflurane; On completion of the neuromonitoring phase of surgery, the patients will be maintained on 1.0 MAC desflurane with remifentanil infusion.; Other Names: 1.0 MAC desflurane (Suprane)
Active Comparator: 0.5 MAC desflurane; The effects of 0.5 MAC desflurane on the amplitude and latency of evoked potentials in spinal surgeries will be examined.	Drug: 1.0 MAC desflurane; On completion of the neuromonitoring phase of surgery, the patients will be maintained on 1.0 MAC desflurane with remifentanil infusion.; Other Names: 1.0 MAC desflurane (Suprane); Drug: 0.5 MAC desflurane; Following induction of anesthesia by propofol, the patients will be maintained on 0.5 MAC desflurane with remifentanil infusion during spinal surgery.; Other Names: 0.5 MAC desflurane (Suprane)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Effect of 0.5 MAC desflurane on evoked potentials - Amplitude (microvolts)	Amplitude of somatosensory- and motor- evoked potentials with use of 0.5 MAC desflurane	During surgery
Effect of 0.5 MAC desflurane on evoked potentials - Latency (milliseconds)	Latency of somatosensory- and motor- evoked potentials with use of 0.5 MAC desflurane	During surgery
Effect of 0.5 MAC desflurane on evoked potentials - Morphology (appearance of the response)	Morphology of somatosensory- and motor- evoked potentials with use of 0.5 MAC desflurane	During surgery
Effect of 0.75 MAC desflurane on evoked potentials - Amplitude (microvolts)	Amplitude of somatosensory- and motor- evoked potentials with use of 0.75 MAC desflurane	During surgery
Effect of 0.75 MAC desflurane on evoked potentials - Latency (milliseconds)	Latency of somatosensory- and motor- evoked potentials with use of 0.75 MAC desflurane	During surgery
Effect of 0.75 MAC desflurane on evoked potentials - Morphology (appearance of the response)	Morphology of somatosensory- and motor- evoked potentials with use of 0.75 MAC desflurane	During surgery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Effect of 1.0 MAC desflurane on evoked potentials - Amplitude (microvolts)	Amplitude of somatosensory- and motor- evoked potentials with use of 1.0 MAC desflurane	intraoperative
Effect of 1.0 MAC desflurane on evoked potentials - Latency (milliseconds)	Latency of somatosensory- and motor- evoked potentials with use of 1.0 MAC desflurane	intraoperative
Effect of 1.0 MAC desflurane on evoked potentials - Morphology (appearance of the response)	Morphology of somatosensory- and motor- evoked potentials with use of 1.0 MAC desflurane	intraoperative

Collaborators and Investigators

• Sponsor: Changi General Hospital
• Investigators: Principal Investigator: Wai May Leong, MMed, Changi General Hospital

Publications and helpful links

General Publications

• Hasan MS, Tan JK, Chan CYW, Kwan MK, Karim FSA, Goh KJ. Comparison between effect of desflurane/remifentanil and propofol/remifentanil anesthesia on somatosensory evoked potential monitoring during scoliosis surgery-A randomized controlled trial. J Orthop Surg (Hong Kong). 2018 May-Aug;26(3):2309499018789529. doi: 10.1177/2309499018789529.
• Sloan TB, Toleikis JR, Toleikis SC, Koht A. Intraoperative neurophysiological monitoring during spine surgery with total intravenous anesthesia or balanced anesthesia with 3% desflurane. J Clin Monit Comput. 2015 Feb;29(1):77-85. doi: 10.1007/s10877-014-9571-9. Epub 2014 Mar 19.
• Macdonald DB, Skinner S, Shils J, Yingling C; American Society of Neurophysiological Monitoring. Intraoperative motor evoked potential monitoring - a position statement by the American Society of Neurophysiological Monitoring. Clin Neurophysiol. 2013 Dec;124(12):2291-316. doi: 10.1016/j.clinph.2013.07.025. Epub 2013 Sep 18. Review.

Study record dates

Study Major Dates

• Study Start (Actual): April 14, 2021
• Primary Completion (Anticipated): November 30, 2022
• Study Completion (Anticipated): November 30, 2022

Study Registration Dates

• First Submitted: January 13, 2021
• First Submitted That Met QC Criteria: January 19, 2021
• First Posted (Actual): January 20, 2021

Study Record Updates

• Last Update Posted (Actual): August 6, 2021
• Last Update Submitted That Met QC Criteria: August 2, 2021
• Last Verified: August 1, 2021

More Information

Terms related to this study

• Keywords: spinal surgery; desflurane; evoked potentials
• Additional Relevant MeSH Terms: Physiological Effects of Drugs; Central Nervous System Depressants; Anesthetics, General; Anesthetics; Anesthetics, Inhalation; Desflurane
• Other Study ID Numbers: Desflurane01

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No