Cerebral Oxygen Desaturation and Postoperative Cognitive Effects in Elderly Patients Operated in Beach Chair Position

INTRODUCTION: Elderly patients may be affected by some extreme positions during surgery. Upright positions may lead to systemic hypotension, cerebral circulation and oxygenation derangements, and postoperative cognitive dysfunction (POCD). Cerebral oxygen saturation monitored by near infrared spectroscopy (NIRS) in elderly patients undergoing arthroscopic shoulder operations in beach chair position (BCP) was assessed to see if this age group showed any failure to compensate for these positional hemodynamic effects and had POCD.
METHODS: After pre-operative baseline mini mental state examination (MMSE) assessment, 105 patients were operated on in beach chair position and monitored using NIRS. Intraoperative data and postoperative cognitive functions were analyzed.
RESULTS: Ninety-seven patients were included in the final analysis. Patients were cohort according to age: After Group ≥65-years old, n=43; Group <65-years old, n=54. In the group of elderly patients, the frequency, the maximum percentage of drop in hypotensive events were higher, the duration was longer (p<0.02, p=0.018); the maximum percentage of regional cerebral oxygen saturation drop, and the duration was larger. (AUC-R, median (IQR): 30 (0.274) versus 0 (0.21); (p=0.014). Three patients had a decline in cognitive function at 24 h that persisted at the 3-month follow-ups; in another 3 patients, cognitive dysfunction was detected 3-months following surgery (p=0.016).
DISCUSSION AND CONCLUSION: Elderly patients undergoing shoulder operations in BCP are at higher risk of serious cerebral hypotension, desaturation and peri-operative cognitive dysfunction than the younger patients.