Effect of adjunctive dexmedetomidine on anesthesia and analgesia requirement and recovery characteristics during Bispectral Index-guided anesthesia for cerebello-pontine angle surgeries: A randomized clinical trial.

BACKGROUND AND AIMS: The study was conceived to elucidate the effects of dexmedetomidine as an anesthetic adjunct to propofol (total intravenous anesthesia) on anesthetic dose reduction and anesthesia recovery parameters in cerebello-pontine angle (CPA) surgeries. MATERIAL AND METHODS: This prospective randomized study was conducted on 49 patients (25 with dexmedetomidine, 24 without). After standardized anesthetic induction, anesthesia was maintained using propofol (via target controlled infusion, titrated to maintain BIS between 40 and 60), fentanyl (0.5 µg/kg/hour) and either dexmedetomidine (0.5 µg/kg/hour) or a sham infusion. Neuromuscular blocking agents were excluded to allow cranial nerve EMG monitoring. Adverse hemodynamic events, recovery parameters (time to opening eyes, obeying commands, and extubation) and postoperative sedation score, shivering score, nausea, and vomiting score were recorded. RESULTS: Propofol and fentanyl utilization (as total dose, adjusted for duration of surgery and body weight, and number of extra boluses) was significantly lower in the dexmedetomidine group. There was no difference in any of the recovery parameters between the two groups. Incidence of bradycardia was significantly higher with dexmedetomidine, while no difference was found for hypotension, hypertension, and tachycardia. CONCLUSION: Dexmedetomidine-fentanyl-propofol anesthesia compares favorably with fentanyl-propofol anesthesia during CPA neurosurgical procedures with regard to anesthesia recovery times, but with lower intraoperative opioid and hypnotic utilization rates.

Regional Cerebral Oxygen Saturation Changes After Decompressive Craniectomy for Malignant Cerebral Venous Thrombosis: A Prospective Cohort Study.

BACKGROUND: Decompressive craniectomy (DC) is a life-saving intervention for malignant cerebral venous thrombosis (CVT). Earlier studies have shown increase in cerebral oxygenation after DC in traumatic brain injury but similar studies are lacking in CVT. We hypothesized that regional cerebral (tissue) oxygen saturation (rSO2) on the side of CVT is lower than the contralateral side and improves after DC. MATERIALS AND METHODS: In this prospective cohort study, rSO2 was monitored using near-infrared spectroscopy technique, before and after DC on both cerebral hemispheres. Data regarding factors likely to affect rSO2 such as systolic blood pressure, partial pressure of oxygen and carbon dioxide in blood (PaO2 and PaCO2), and hemoglobin were simultaneously collected. The primary outcome measure was pre-post change in rSO2 on the ipsilateral cerebral hemisphere. The secondary outcomes were in-hospital mortality and duration of postoperative hospital stay. RESULTS: Seventeen patients underwent DC during the 6-month study period. Their mean age was 39.2±12.4 years. The pre-post DC change in rSO2 on the hemisphere with CVT was significant (mean difference=3.6%; 95% confidence interval, 1.5-5.7; P=0.002). One patient died in the hospital. There was no difference in the duration of postoperative hospital stay (10 d [range, 6 to 21 d] vs. 14 d [range, 1 to 30 d], P=0.92) between patients with preoperative ipsilateral rSO2 <60% and >60%. There was no correlation between PaO2, PaCO2, systolic blood pressure, and hemoglobin with rSO2. CONCLUSIONS: Patients with malignant CVT had a lower rSO2 on ipsilateral side of the lesion, which improved significantly after DC. Preoperative rSO2 was not correlated with the duration of hospital stay.