Related Experiment Video
Updated: Mar 21, 2026
A Mouse Model of Orthopedic Surgery to Study Postoperative Cognitive Dysfunction and Tissue Regeneration
Published on: February 27, 2018
Effects of Single Low Dose of Dexamethasone before Noncardiac and Nonneurologic Surgery and General Anesthesia on
Livia Stocco Sanches Valentin1, Valeria Fontenelle Angelim Pereira1, Ricardo S Pietrobon2
1Department of Anesthesia, LIM 8 -Laboratory of Anesthesiology, Faculdade de Medicina da Universidade de São Paulo, São Paulo, São Paulo, Brazil.
Unlabelled:
Postoperative cognitive dysfunction (POCD) is a multifactorial adverse event most frequently in elderly patients. This study evaluated the effect of dexamethasone on POCD incidence after noncardiac and nonneurologic surgery.
Methods:
One hundred and forty patients (ASA I-II; age 60-87 years) took part in a prospective phase III, double blind, randomized study involving the administration or not of 8 mg of IV dexamethasone before general anesthesia under bispectral index (BIS) between 35-45 or 46-55. Neuropsychological tests were applied preoperatively and on the 3rd, 7th, 21st, 90th and 180th days after surgery and compared with normative data. S100β was evaluated before and 12 hours after induction of anesthesia. The generalized estimating equations (GEE) method was applied, followed by the posthoc Bonferroni test considering P<0.05 as significant.
Results:
On the 3rd postoperative day, POCD was diagnosed in 25.2% and 15.3% of patients receiving dexamethasone, BIS 35-45, and BIS 46-55 groups, respectively. Meanwhile, POCD was present in 68.2% and 27.2% of patients without dexamethasone, BIS 35-45 and BIS 46-55 groups (p<0.0001). Neuropsychological tests showed that dexamethasone associated to BIS 46-55 decreased the incidence of POCD, especially memory and executive function. The administration of dexamethasone might have prevented the postoperative increase in S100β serum levels.
Conclusion:
Dexamethasone can reduce the incidence of POCD in elderly patients undergoing surgery, especially when associated with BIS 46-55. The effect of dexamethasone on S100β might be related with some degree of neuroprotection.
Trial Registration:
www.clinicaltrials.gov NCT01332812.
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