Brain Tumor, Surgery
Conditions
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.
Interventions
DRUGPropofol-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.
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).
Sponsors
Mansoura University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
SUPPORTIVE_CARE
Masking
SINGLE (Caregiver)
Eligibility
Sex/Gender
ALL
Age
20 Years to 60 Years
Healthy volunteers
No
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,
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| 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 |
| 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 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
| Measure | Time frame | Description |
|---|---|---|
| Postoperative level of sedation | every 5 min for 60 min, after extubation | all patients will be evaluated using Ramsay sedation scale |
| Time for first analgesic request from extubation | for 6 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 | — |
| Intensive care unit stay | for 10 days after surgery | — |
| Total analgesics received | for 24 hours after surgery | — |
| 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 | — |
Outcome results
None listed