Role of Dexmedetomidine on Hemodynamics and Anesthetic Requirement in Patients Undergoing Elective Infratentorial...

Infratentorial tumor resections can pose a considerable anesthetic challenge because the posterior fossa is close to critical brainstem and cranial nerve structures. Surgical manipulation here can cause significant changes in cerebral blood flow and hemodynamics, complicating the regulation of intracranial pressure and cerebral perfusion in patients already at elevated risk. This study was conducted to evaluate the impact of dexmedetomidine compared with a placebo on intraoperative hemodynamics and anesthetic requirements during surgery for infratentorial brain tumors.

A total of 120 American Society of Anesthesiologists 2 patients scheduled for elective infratentorial tumor surgery were divided into two groups, Group D and Group C, each comprising 60 individuals. Group D received dexmedetomidine at 1 μg/kg over 10 min, followed by a maintenance infusion of 0.4 μg/kg/h, which was discontinued at skin closure. In contrast, Group C received a normal saline infusion. Thirty minutes after initiating the maintenance infusion, general anesthesia was induced with fentanyl, propofol, vecuronium, air, oxygen, and isoflurane. The trachea was intubated. Fentanyl was administered intermittently in response to increases in heart rate (HR) and blood pressure. Throughout the intraoperative period, HR, mean arterial pressure, SpO2, EtCO2, and the requirements for isoflurane and fentanyl were recorded and compared.

The group receiving dexmedetomidine had stable hemodynamics throughout the intraoperative period. The mean blood pressure across time points in the dexmedetomidine group was lower than in the control group. The consumption of isoflurane was lower in Group D than in Group C across different time points during the surgery. The requirement of fentanyl in Group D was 111.76 ± 16.43 μg, whereas that in Group C was 151.16 ± 29.34 μg (P ≤ 0.001). This finding suggests a possible enhanced analgesic or opioid-sparing effect of dexmedetomidine in Group D.

The use of dexmedetomidine infusion in patients scheduled for infratentorial brain tumor surgery ensures stable perioperative hemodynamics, reduces isoflurane requirements, and reduces intraoperative fentanyl needs.