Control of Hemodynamic Responses and Perioperative Outcomes in Transsphenoidal Pituitary Surgery: A Qualitative Systematic Review of the Available Evidence

Effects of Low versus Intermediate Doses of Dexmedetomidine Infusion on Blood Loss, Hemodynamics, and Operative Time in Transsphenoidal Pituitary Tumor Removal: A Prospective Randomized Study

Background Dexmedetomidine, an alpha-2 agonist, has been widely used as an anesthetic adjunct for transsphenoidal pituitary resection. However, there is no consensus on the appropriate infusion dosage. This study aimed to compare the effects of low (0.2 mcg/kg/h) and intermediate (0.5 mcg/kg/h) dexmedetomidine infusions during anesthetic maintenance on blood loss, hemodynamics, and operating time.

Methods A randomized controlled trial involving two centers was conducted. Between December 2015 and November 2019, 80 patients (40 in each group) who underwent elective transsphenoidal pituitary tumor resection were recruited. Dexmedetomidine was administered to group I at a loading dose of 0.5 mcg/kg, followed by 0.2 mcg/kg/h, and to group II at the same loading dose, followed by 0.5 mcg/kg/h. Comparative analyses were performed using the Student's t-test, repeated-measures analysis of variance, and Mann–Whitney U test; p-values < 0.05 were considered statistically significant.

Results Eighty patients were analyzed. Patient demographics were comparable. The difference in intraoperative blood loss between both groups (320 [220–525] vs. 250 [100-487] mL, p = 0.070) was not statistically significant. There were no differences in blood pressure or heart rate between the groups. In group II, the procedure took significantly less time (179 vs. 142 minutes, p = 0.018), with more episodes of transient hypotension (p = 0.034).

Conclusion When maintaining anesthesia for transsphenoidal pituitary resection, dexmedetomidine infusions of 0.2 and 0.5 mcg/kg/h showed the same effect on blood loss and hemodynamics; however, significantly more episodes of transient hypotension and shorter operating times were noted with the latter.

Anesthetic management during transsphenoidal pituitary surgery

PURPOSE OF REVIEW

Pituitary adenoma resections comprise a large proportion of intracranial tumor surgeries. This patient population is medically and physiologically complex and requires careful perioperative planning and management on the part of the anesthesiologist. This review will summarize anesthetic considerations for pre, intra, and postoperative management of patients undergoing transsphenoidal pituitary surgery.

RECENT FINDINGS

An endoscopic approach is favored for patients undergoing transsphenoidal pituitary surgery. Hemodynamic monitoring is important to maintain cerebral perfusion and avoid risk of bleeding; however, 'controlled' hypotension may have adverse effects. Multimodal analgesia is effective for the management of postoperative pain and may reduce the risk of postoperative complications, including respiratory depression and postoperative nausea and vomiting.

SUMMARY

Transsphenoidal pituitary surgery is a preferred approach for the surgical management of nonfunctioning pituitary macroadenomas with symptoms of mass effect and functioning adenomas that cannot be otherwise managed medically. Understanding tumor pathologies and systemic effects are essential for preoperative planning and providing safe anesthetic care during the perioperative period.