Mild acute stress prevents the memory impairment induced by long-term isoflurane anesthesia

Abstract

Objectives Long-term isoflurane anesthesia exposure could result in postoperative cognitive dysfunction (POCD). Preoperative stress is also reported to be a risk factor of POCD. However, it is unknown whether acute stress could impair memory after long-term isoflurane anesthesia. Methods In this study, we categorized the mice with acute stress into mild (30 min restraint stress), moderate (60 min restraint stress), and severe (120 min restraint stress) stress groups and then we used Open-Field Test (OFT) to detect whether different scales of acute restraint stress successfully induced acute stress in mice. The memory performance of mice was measured using contextual and cued memory test, and the brain-derived neurotrophic factor protein levels of hippocampus was detected by Western blot. Results We verified that mild stress has pro-cognitive effect, but severe stress has amnestic effect. Moreover, we found that mild and moderate other than severe acute stress could partially attenuate the memory impairment induced by long-term isoflurane anesthesia. Conclusion Mild and moderate acute stress could partially attenuate the memory impairment induced by long-term isoflurane anesthesia.

Early postoperative cognitive decline—are there any preventive strategies for surgical patients in the emergency setting?

“…Melatonin has also been advocated in cognitive decline, due to its known properties of adjusting production of proand anti-inflammatory cytokines, and scavenging free radicals molecules [57]. Animal model studies evaluated exogenous melatonin effect after exposure to the volatile anesthetic isoflurane and the results indicated an improvement in the sleepwake pattern due to circadian rhythm resetting [58,59]. The published studies in human subjects validated the previous findings regarding the sleep-wake cycle and also indicated a preserved neurocognitive function in the immediately postoperative period in patients receiving melatonin [60,61].…”