Boston – Perioperative neurocognitive disorder (PND) is one of the most common postoperative complications in older adults and is associated with adverse postoperative outcomes. However, the causes, underlying mechanisms and interventions remain largely unknown.
A clinical and animal study led by investigators at Massachusetts General Hospital (MGH), Xuzhou Medical University, Shanghai Jiao Tong University, Fudan University and Shanghai10.th The hospital has shown that postoperative olfactory impairment is associated with postoperative cognitive impairment in patients and rodents.
Olfactory enrichment may prevent or treat postoperative cognitive impairment in rodents. The findings are published in the Annals of Surgery.
In this study, the team showed that patients who developed PND had poorer sense of smell before and after surgery.
In animal studies, researchers found that anesthesia/surgery resulted in impairment of both olfactory and cognitive function, increased amounts of interleukin-6 in the blood and nasal epithelium, decreased amounts of olfactory receptor neurons in the nasal epithelium, and decreased amounts of synapse markers. brain tissue of rats.
Importantly, these changes were attenuated by odor enrichment and treatment with the interleukin-6 antibody.
“These results help to understand the causes and underlying mechanisms of PND, including the contribution of the peripheral nervous system to PND”, said senior author Zhongkong Xie, MD, PhD, director of the Geriatric Anesthesia Research Unit in the MGH Department of Anesthesia, Critical Care says. and pain medicine. Professor of Anesthesia at Zee Harvard Medical School, Henry K. Beecher is a professor.
“These data also suggest that odor enrichment, a non-drug treatment, can reduce postoperative impairment in rats, suggesting that we have a potential to prevent or treat PND in patients.” Might consider using odor enhancement”, says Xie.
Co-senior author Jun-Li Cao, MD, PhD, director of the Leading Laboratory of Anesthesiology, Jiangsu Province, China, says: “While PND is very common in older patients, more clinical studies are needed to assess whether Can odor enrichment reduce the incidence and severity of PND in older patients”.
Anesthesia/surgery increases the amount of interleukin-6 in the blood and olfactory epithelium of the nasal cavity of rats, which then causes olfactory impairment by depleting olfactory sensory neurons, leading to a decrease in synapse numbers in the brain tissue of rats. and result in cognitive impairment.
Study co-senior author Yuan Shen, MD, PhD, of Shanghai Jiao Tong University and Shanghai 10, says, “We expect this work to be clinical and pre-clinical to further reveal the underlying mechanisms and interventions for PND.” Will spur more research on both.”th hospital. Dr. Shen is a professor of psychiatry at Shanghai Jiao Tong University and a former researcher at Massachusetts General Hospital and Harvard Medical School.
CE Zhang from the MGH Department of Anesthesia, Critical Care and Pain Medicine; Yuan Han of Xuzhou Medical University and Xiaojun Liu from Fudan University, MGH Department of Anesthesia, Critical Care and Pain Medicine are study co-authors.
Additional authors include Hong Tan, Yuanlin Dong, Yiying Zhang, Fang Liang from the MGH Department of Anesthesia, Critical Care and Pain Medicine; Hui Zheng from MGH Biostatistics Center; Gregory Crosby from Brigham and Women’s Hospital and Harvard Medical School; Deborah J. from the Perelman School of Medicine and the University of Pennsylvania. bud; and Edward R., from Beth Israel Deaconess Medical Center and Harvard Medical School. Marcantonio.
The study was supported by the National Institutes of Health, including the National Institute on Aging.
About Massachusetts General Hospital
Massachusetts General Hospital, established in 1811, is the original and largest teaching hospital of Harvard Medical School. Mass General Research Institute conducts the largest hospital-based research program in the country, with annual research operations of more than $1 billion and involving more than 9,500 researchers working in more than 30 institutions, centers and departments . In August 2021, Mass General was designated #4. US news and world report List of “Best Hospitals in America”.