Effect of Propofol-Dexmedetomidine on Cerebral Oxygenation and Metabolism During Brain Tumor Resection
- Conditions
- Brain TumorSurgery
- Interventions
- Drug: Propofol-Dexmedetomidine group
- Registration Number
- NCT02575521
- Lead Sponsor
- Mansoura University
- Brief Summary
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.
- 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.
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 50
- American Society of Anesthesiologists physical status III or IV.
- Patients scheduled for elective brain tumor resection
- 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 & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description Propofol-Dexmedetomidine group Propofol-Dexmedetomidine group this group is planned to receive intravenous anaesthesia only Sevoflurane group Sevoflurane group this group is planned to receive sevoflurane/fentanyl anaesthesia
- Primary Outcome Measures
Name Time Method 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) immediately after cannulation (arterial and jugular), every 30 min during surgery and after complete closure of the scalp eCMRO2=Ca- jO2 x(PaCO2 ∕ 100) Where Ca jO2 is arterio-jugular O2 content difference. PaCO2 is arterial CO2 tension
Cerebral Extraction Rate of O2 (CEO2) immediately after cannulation (arterial and jugular), every 30 min during surgery and after complete closure of the scalp. Calculated as the differences between arterial and jugular bulb O2 saturations, CEO2 = SaO2 - SjvO2
Cerebral Blood Flow equivalent (CBFe) immediately after cannulation (arterial and jugular), every 30 min during surgery and after complete closure of the scalp Which is an index of flow metabolism relationship, calculated as a reciprocal of arterio-jugular O2 content difference. CBFe = 1 ∕CaO2-CjvO.
- Secondary Outcome Measures
Name Time Method Time for first analgesic request from extubation for 6 hours after surgery Total analgesics received for 24 hours after surgery 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 every 5 min for 60 min, after extubation all patients will be evaluated using Ramsay sedation scale
Intensive care unit stay for 10 days after surgery