Short-Term and Long-Term Effects of Dexamethasone on Cognitive Dysfunction Induced by Sevoflurane in Adult Rats.

OBJECTIVE: Postoperative cognitive dysfunction (POCD) is common after anaesthesia in elderly patients. However, it may appear in patients of all ages. The main pathogenesis of cognitive dysfunction remains unclear, although there is some evidence that brain inflammation may alter cognitive abilities. In the present study, we aim to evaluate short-term and long-term effects of dexamethasone on cognitive dysfunction induced by sevoflurane anaesthesia in adult rats.

METHODS: Seven-month-old 30 male Wistar albino rats were randomised into three groups: sevoflurane group (exposure to sevoflurane), sevoflurane + dexamethasone group (exposure to sevoflurane and dexamethasone injection), and control group (exposure to 100% oxygen). Spatial learning and short-term (7 days after exposure) and long-term (30 days after exposure) memory were evaluated using Morris water maze test.

RESULTS: Sevoflurane induced significant deficit in spatial learning and short-term and long-term memory in adult rats. Dexamethasone-treated animals exposed to sevoflurane had equivalent performance as control animals in training and probe trials.

CONCLUSION: Sevoflurane may impair spatial learning and short-term and long-term memories in adult rats. The co-administration of dexamethasone and sevoflurane may ameliorate short-term and long-term cognitive dysfunctions induced by sevoflurane in adult rats.