The influence of general and regional anesthesia on cognitive status in elderly and senile patients undergoing primary and revision arthroplasty of lower limb joints

BACKGROUND: Recently, the impact of general anaesthesia on the patient's cognitive state has been increasingly discussed. The detrimental effects of the general anaesthetic components can be clinically manifested in the form of impaired memory, coordination and attention, as well as in the development of delirium, which increases postoperative mortality. AIM: To evaluate the influence of methods of general anaesthesia and the combination of regional anaesthesia and intravenous sedation on the development of early postoperative cognitive dysfunction in older and elderly patients undergoing surgery for endoprosthesis of large joints of the lower limb, such as knee and hip joints. MATERIALS AND METHODS: A single-blind, randomized study was conducted in 122 aged patients with orthopedic pathology of the lower limb joints undergoing treatment in the Priorov National Medical Research Center of Traumatology and Otrhopaedics. The effect of general anesthesia and its components in combination with spinal anesthesia with bupivacaine or levobupivacaine on the development of cognitive impairment in the early postoperative period was assessed using the Montreal Mental Status Assessment Scale MoCA. RESULTS: Postoperative delirium developed in 3.3% of patients in the spinal anaesthesia group with intravenous midazolam sedation, early postoperative cognitive dysfunction developed in 26.7% of patients in the spinal anaesthesia group with intravenous midazolam and diazepam sedation, and in 16.7% of patients in the dexmedetomidine group with intravenous dexmedetomidine sedation. In the sevoflurane general anaesthesia group, the incidence of cognitive impairment was significantly higher than in the spinal anaesthesia groups: postoperative delirium developed in 6.3% of patients, and postoperative cognitive dysfunction was found in 50% of older and elderly patients. CONCLUSION: The use of spinal anaesthesia with intravenous sedation with benzodiazepines or dexmedetomidine has a significantly lower effect on the incidence of early postoperative cognitive impairment compared with general anaesthesia with sevoflurane in elderly and older patients undergoing major joint replacement surgery. Intravenous sedation with dexmedetomidine is preferable to spinal anaesthesia.