Sevoflurane and desflurane effects on early cognitive function after low-risk surgery: A randomized clinical trial

Deleterious effects on short-term and long-term quality of life have been associated with the development of postoperative cognitive dysfunction (POCD) after general anesthesia. Yet, the progress in the field is still required. Most of the studies investigate POCD after major surgery, so scarce evidence exists about the incidence and effect different anesthetics have on POCD development after minor procedures. In this study, we compared early postoperative cognitive function of the sevoflurane and desflurane patients who experienced a low-risk surgery of thyroid gland.

Eighty-two patients, 40 years and over, with no previous severe cognitive, neurological, or psychiatric disorders, appointed for thyroid surgery under general anesthesia, were included in the study. In a random manner, the patients were allocated to either sevoflurane or desflurane study arms. Cognitive tests assessing memory, attention, and logical reasoning were performed twice: the day before the surgery and 24 h after the procedure. Primary outcome, magnitude of change in cognitive testing, results from baseline. POCD was diagnosed if postoperative score decreased by at least 20%.

Median change from baseline cognitive results did not differ between the sevoflurane and desflurane groups (-2.63%, IQR 19.3 vs. 1.13%, IQR 11.0; p = .222). POCD was detected in one patient (1.22%) of the sevoflurane group. Age, duration of anesthesia, postoperative pain, or patient satisfaction did not correlate with test scores. Intraoperative temperature negatively correlated with total postoperative score (r = -0.35, p = .007).

Both volatile agents proved to be equivalent in terms of the early cognitive functioning after low-risk thyroid surgery. Intraoperative body temperature may influence postoperative cognitive performance.