Effect of Propofol-Dexmedetomidine on Cerebral Oxygenation and Metabolism During Brain Tumor Resection

Effect of Propofol-Dexmedetomidine Total Intravenous Anaesthesia on Cerebral Oxygenation and Metabolism During Brain Tumor Resection Compared to Sevoflurane Anaesthesia

Despite theoretical benefits of intravenous agents, volatile agents remain popular. In a study comparing desflurane, isoflurane, and sevoflurane in a porcine model of intracranial hypertension, at equipotent doses and normocapnia, cerebral blood flow (CBF) and intra-cranial pressure (ICP) were least with sevoflurane.

Propofol is the most commonly used intravenous anesthetic. It has many theoretical advantages by reducing cerebral blood volume (CBV) and ICP and preserving both autoregulation and vascular reactivity. Neurosurgical patients anaesthetized with propofol were found to have lower ICP and higher CPP than those anaesthetized with isoflurane or sevoflurane.

The well known pharmacodynamic advantages of intravenous anesthetics may give this group of drugs superior cerebral effects when compared with inhalation anesthetics.

Study Overview

• Status: Completed
• Conditions: Brain Tumor; Surgery
• Intervention / Treatment: Drug: Propofol-Dexmedetomidine group; Drug: Sevoflurane group

Detailed Description

The aim of this study is to evaluate the cerebral haemodaynamics and global cerebral oxygenation as well as the systemic haemodaynamic changes using dexmedetomidine, propofol and fentanyl as total intravenous anaesthestics (TIVA) in comparison with sevoflurane - fentanyl anesthesia in brain tumor resection.

Indicators of global cerebral oxygenation and haemodynamics will be calculated using jugular bulb and peripheral arterial blood sampling.

• Induction: propofol, 1.5 - 2 mg/kg.
• Muscle Relaxants: atracurium, 0.5 mg/kg with induction and 0.1 mg/kg/20min. for maintenance.
• Cannulation: Arterial cannula: under complete aseptic conditions 20G cannula was inserted into the radial artery of non dominant hand after performing modified Allen's test and local infiltration of 0.5ml xylocaine 2%.

Central venous catheter: A suitable central venous catheter will be inserted into Rt subclavian vein under complete aseptic technique, its correct position will be confirmed with chest X-Ray.

Jugular bulb catheterization: Under strict sterile technique the right internal jugular vein will be cannulated in a retrograde technique with confirmation of the catheter tip position using X-Ray (C- arm). Puncture site will be at the level of cricoid cartilage behind the anterior border of the sternocleido-mastoid muscle.

• Study Type: Interventional
• Enrollment (Actual): 50
• Phase: Not Applicable

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 20 years to 60 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• American Society of Anesthesiologists physical status III or IV.
• Patients scheduled for elective brain tumor resection

Exclusion Criteria:

• Morbid obese patients.
• Severe or uncompensated cardiovascular diseases.
• Severe or uncompensated renal diseases.
• Severe or uncompensated hepatic diseases.
• Severe or uncompensated endocrinal diseases.
• Pregnancy.
• Postpartum or lactating females.
• Allergy to one of the agents used.
• Severely altered consciousness level.
• Sitting position during surgery.
• Prone position during surgery,

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Propofol-Dexmedetomidine group; this group is planned to receive intravenous anaesthesia only	Drug: Propofol-Dexmedetomidine group; Porofol (1.5-2 mg/kg/h) infusion, Dexmedetomidine (0.2-1µg/kg/h) infusion and Fentanyl in repeated doses (50µ) when needed (heart rate or mean arterial blood pressure increase more than 20% of the basal value). Maintenance infusions will start immediately after induction.
Active Comparator: Sevoflurane group; this group is planned to receive sevoflurane/fentanyl anaesthesia	Drug: Sevoflurane group; Sevoflurane at a concentration of 2-2.5%., Fentanyl in repeated doses (50µ) when needed (heart rate or mean arterial blood pressure increase more than 20% of the basal value).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Arterio-Jugular oxygen content difference		immediately after cannulation (arterial and jugular), every 30 min during surgery and after complete closure of the scalp
Estimated cerebral metabolic rate for O2 (eCMRO2)	eCMRO2=Ca- jO2 x(PaCO2 ∕ 100) Where Ca jO2 is arterio-jugular O2 content difference. PaCO2 is arterial CO2 tension	immediately after cannulation (arterial and jugular), every 30 min during surgery and after complete closure of the scalp
Cerebral Extraction Rate of O2 (CEO2)	Calculated as the differences between arterial and jugular bulb O2 saturations, CEO2 = SaO2 - SjvO2	immediately after cannulation (arterial and jugular), every 30 min during surgery and after complete closure of the scalp.
Cerebral Blood Flow equivalent (CBFe)	Which is an index of flow metabolism relationship, calculated as a reciprocal of arterio-jugular O2 content difference. CBFe = 1 ∕CaO2-CjvO.	immediately after cannulation (arterial and jugular), every 30 min during surgery and after complete closure of the scalp

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Heart rate		will be monitored continiously and recorded immediately after intubation, every 30 min during surgery and immediately after closure of the scalp
Blood pressure		will be monitored continiously and recorded immediately after intubation, every 30 min during surgery and immediately after closure of the scalp
End-tidal carbon dioxide tension		will be monitored continiously and recorded immediately after intubation, every 30 min during surgery and immediately after closure of the scalp
Central venous pressure		will be monitored continiously and recorded immediately after intubation, every 30 min during surgery and immediately after closure of the scalp
Postoperative level of sedation	all patients will be evaluated using Ramsay sedation scale	every 5 min for 60 min, after extubation
Time for first analgesic request from extubation		for 6 hours after surgery
Total analgesics received		for 24 hours after surgery
Intensive care unit stay		for 10 days after surgery

Collaborators and Investigators

• Sponsor: Mansoura University
• Investigators: Principal Investigator: Ahmed A. Daif, MD, Anaesthesia and Intensive Care Department, College of Medicine, Mansoura University

Study record dates

Study Major Dates

• Study Start (Actual): August 1, 2015
• Primary Completion (Actual): October 1, 2017
• Study Completion (Actual): November 1, 2017

Study Registration Dates

• First Submitted: October 7, 2015
• First Submitted That Met QC Criteria: October 11, 2015
• First Posted (Estimate): October 14, 2015

Study Record Updates

• Last Update Posted (Actual): November 8, 2017
• Last Update Submitted That Met QC Criteria: November 6, 2017
• Last Verified: November 1, 2017

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Neoplasms; Neoplasms by Site; Central Nervous System Neoplasms; Nervous System Neoplasms; Brain Neoplasms; Physiological Effects of Drugs; Adrenergic Agents; Neurotransmitter Agents; Molecular Mechanisms of Pharmacological Action; Central Nervous System Depressants; Peripheral Nervous System Agents; Analgesics; Sensory System Agents; Anesthetics, Intravenous; Anesthetics, General; Anesthetics; Analgesics, Non-Narcotic; Platelet Aggregation Inhibitors; Adrenergic alpha-2 Receptor Agonists; Adrenergic alpha-Agonists; Adrenergic Agonists; Hypnotics and Sedatives; Anesthetics, Inhalation; Propofol; Dexmedetomidine; Sevoflurane
• Other Study ID Numbers: MFM-IRB-14-08-2015