Evaluation of the relationship between the level of controlled hypotension applied during rhinoplasty and septoplasty surgeries and the incidence of postoperative cognitive dysfunction and delirium

Objective: Controlled hypotension is a commonly used anesthesia technique aimed at reducing blood loss and minimizing complications, particularly in surgeries involving richly vascularized tissues. While previous studies have focused on the short-term cognitive effects, long-term impacts remain unexplored. This study examines the effects of controlled hypotension on cerebral blood flow and its potential impact on short-, medium-, and long-term postoperative cognitive dysfunction or delirium. Materials and Methods: This prospective, randomized, double-blind study included 70 patients scheduled for rhinoplasty or septoplasty. Patients were divided into two equal groups (n=35). Group A targeted a mean arterial pressure (MAP) of 50-57 mmHg, while Group B targeted 58-65 mmHg. Perioperative monitoring included blood pressure, heart rate, oxygen saturation, rSO2, entropy values, and blood lactate levels. MMT and DRS-R-98 scores were evaluated preoperatively and postoperatively. Findings: In the assessment of postoperative delirium, it was observed that patients in Group A had higher DRS-R-98 scores at both measurement points. The number of patients diagnosed with delirium in the recovery unit was higher in Group A compared to Group B. Correlation was identified between the duration of surgery and the occurrence of delirium. No significant difference was observed between the groups regarding the development of postoperative cognitive dysfunction Conclusion: It is predicted that a mean arterial pressure as low as 50 mmHg does not pose a long-term risk in terms of delirium and postoperative cognitive dysfunction (POCD). The higher incidence of delirium observed in group A in the recovery unit suggests that patients exposed to lower mean arterial pressure should be monitored more carefully in the early period. Keywords: Controlled Hypotension, Postoperative Cognitive Dysfunction, Delirium, Rhinoplasty, Septoplasty.