Desflurane and Brain Relaxation in Craniotomy

Study Overview
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Brief Summary
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Optional brain relaxation improves the surgeon's operating conditions and is likely to minimize the degree of retraction injury ,with the potential for providing patients with a better outcome. The choice of anesthetic drugs can affect intraoperative brain relaxation. Propofol suppresses brain metabolism, reduces cerebral blood flow, and provides satisfactory brain relaxation. Desflurane is often criticized in neurosurgery due to its cerebral vasodilation and potential to increase intracranial pressure, however, it has been found to have a little clinical significance. This study intends to compare the effects of desflurane with propofol on brain relaxation in patients with supratentorial tumors under mild hyperventilation, and to provide new clinical evidence for the use of desflurane in neurosurgical anesthesia.

Detailed Description
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To compare the effect of desflurane versus propofol combined with remifentanil anesthesia on brain relaxation in patients undergoing supratentorial tumor surgery with mild hyperventilation, and compare the emergence time and common complications during recovery.

Official Title
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Comparison of Desflurane and Propofol for Brain Relaxation in Patients Undergoing Supratentorial Craniotomy：a Randomized Controlled Study

Conditions
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Supratentorial Tumor

Intervention / Treatment
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* Drug: Desflurane
* Drug: Propofol


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 18-60 years Scheduled for elective craniotomy for supratentorial cerebral tumors ASA status I-III Glasgow score of 15 No clinical signs of intracranial hypertension Preoperative brain imaging (CT or MRI) with midline shift less than 5mm Informed consent signed by patients Exclusion Criteria: Scheduled intraoperative motor evoked potential monitoring Patients with cerebral vascular diseases Uncontrolled cardiopulmonary disease Schedule to retain tracheal intubation after surgery Unable to comprehend and cooperate with the examination BMI > 30 Kg/m-2 Emergency surgery History of related anesthetic allergy

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Desflurane inhalational anesthesia<br> | Drug: Desflurane<br>* After induction, anesthesia will be maintained with 0.8-1.3 MAC desflurane and 0.05-0.2 μg/kg/min remifentanil.<br>* Other names: inhalational anesthesia;|
| Active Comparator: Propofol total intravenous anesthesia<br> | Drug: Propofol<br>* After induction, anesthesia will be maintained with 6-8 mg/kg/h propofol and 0.05- 0.2 μg/kg/min remifentanil<br>* Other names: total intravenous anesthesia;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Proportion of satisfactory brain relaxation | Assessed by the neurosurgeon using a 4-point scale (1= perfectly relaxed, 2= satisfactorily relaxed, 3= firm brain, 4=bulging brain) at the opening of the dura mater, score 1 and 2 represent satisfactory brain relaxation | during surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Emergence time | from drug discontinuation to eye opening | from drug discontinuation to eye opening, assessed up to 1 hours | 
| Extubation time | from drug discontinuation to tracheal extubation | from drug discontinuation to tracheal extubation, assessed up to 1 hours | 
| Postoperative complications | incidence of hypoxemia, hypotension, hypertension, tachycardia, bradycardia, agitation, shivering. | from drug discontinuation to discharge from PACU (Postanesthesia care unit), assessed up to 3 hours | 
| Postoperative pain and postoperative nausea and vomiting (PONV) | evaluated by Visual Analogue Score(VAS). | during the PACU stay and postoperative day 1. | 
| Duration in PACU (Postanesthesia care unit) | time from entering PACU to exiting PACU | from entering PACU to exiting PACU, an expected average of 1 hour | 
| Early postanesthesia cognitive recovery | evaluated by Short Orientation Memory Concentration Test (SOMCT) | at 15, 30min after tracheal extubation | 
| Dural tension | evaluated using a 4-point scale after bone flap removal. | during surgery | 
| Quality of anesthesia recovery | assessed by quality of recovery-15 scale (QoR-15) | at postoperative day 1 | 
| Anesthesia expenses | Total cost of anesthesia | at postoperative day 1 |