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Malnutrition has been considered as a risk factor for postoperative delirium (POD). The Prognostic Nutritional Index (PNI) is a validated tool for assessing nutritional status. This study aimed to investigate the association between preoperative PNI values and the occurrence of POD in elderly surgical patients. Methods: The retrospective cohort study included 361 elderly individuals who underwent noncardiac surgery between 2018 and 2019. Perioperative data were collected from the patients' medical records. PNI was used to evaluate preoperative nutritional status. The primary outcome was the occurrence of POD. Univariate and multivariate logistic regression analyses were used to identify key factors associated with POD and assess the relationship between PNI values and the occurrence of POD. Receiver operating characteristic (ROC) curve analysis was used to assess the predictive value of PNI for POD. Results: Seventy-two (19.9%) individuals developed postoperative delirium after surgery. Compared with patients of normal nutrition status (PNI ≥ 50), mild malnutrition (PNI 45-50) did not increase the risk of POD, while patients with moderate to severe malnutrition (PNI 40-45) (odds ratio [OR], 2.92; 95% confidence interval [CI], 1.31-6.50) and serious malnutrition (PNI < 40) (OR, 3.15; 95% CI, 1.12-8.83) were more likely to develop POD. The cut-off value of PNI was 46.05 by ROC curve analysis, the area under the curve (AUC) was 0.69 (95% CI 0.62-0.77). Conclusion:Preoperative PNI value is related to postoperative delirium in elderly patients after noncardiac surgery.

BackgroundPostanesthetic shivering is a common complication of anesthesia, which accounts for much discomfort in postoperative patients and may increase postoperative complications in high-risk patients. Due to the lack of high-quality evidence, it is difficult to draw a conclusion about optimal anti-shivering medication. The main purpose of this meta-analysis was to analyze and evaluate the efficacy and safety of prophylactic use of ketamine for preventing postanesthetic shivering.MethodsWe searched the following databases: Medline, Embase, and the Cochrane Central Register of Controlled Trails for randomized controlled trials. The primary outcome observed was the difference of the incidence rate of postanesthetic shivering between ketamine group and placebo group. The secondary outcomes were the sedation score and incidence of the side effects caused by ketamine and any other drugs utilized in the studies.ResultsIn this meta-analysis, we analyzed a total of 16 trials including 1485 patients. Ketamine reduced the incidence rate of postanesthetic shivering compared to a placebo (odds ratio [OR]: 0.13, 95% confidence interval [CI]: 0.06 to 0.26, P<0.01). Regarding side effects, there was no evident variability of the incidence of nausea and vomiting. Usage of ketamine was associated with a lower rate of hypotension and bradycardia when compared to a placebo. Hallucinations were more frequently observed in patients who received higher doses of ketamine. No significant difference was found in the incidence of postanesthetic shivering with ketamine versus other pharmacological interventions.ConclusionsKetamine can prevent postanesthetic shivering without severe side effects. However, ketamine shows no advantage over other anti-shivering drugs.

IntroductionThe blood‐brain barrier (BBB) disruption contributes to postoperative delirium, but cost‐effective and non‐invasive assessment of its permeability is not practicable in the clinical settings. Urine albumin to creatinine ratio (UACR), reflecting systemic vascular endothelial dysfunction, may be a prognostic and predictive factor associated with postoperative delirium. The aim was to analyze the relationship between UACR and postoperative delirium in elderly patients undergoing elective non‐cardiac surgery.Materials and methodsThrough stratified random sampling, a cohort of 408 individuals aged 60 years and older scheduled for elective non‐cardiac surgery were included between February and August 2019 in the single‐center, prospective, observational study. The presence of delirium was assessed using the Confusion Assessment Method (CAM) or Confusion Assessment Method for the ICU (CAM‐ICU) on the day of surgery, at 2 h after the surgery ending time and on the first 3 consecutive days with repeated twice‐daily, with at least 6‐h intervals between assessments. Urine samples were collected on one day before surgery, and 1st day and 3rd day after surgery. The primary outcome was the presence of postoperative delirium, and association of the level of UACR with postoperative delirium was evaluated with unadjusted/adjusted analyses and multivariable logistic regression.ResultsPostoperative delirium was observed in 26.75% (107 of 400) of patients within 3 days post‐surgery. UACR‐Pre (OR, 1.30; 95% CI, 1.14–1.49, p < 0.001), UACR‐POD1 (OR, 1.20; 95% CI, 1.13–1.27, p < 0.001), and UACR‐POD3 (OR, 1.14; 95% CI, 1.08–1.20, p < 0.001) between the delirium and non‐delirium groups show a significant difference, even after adjusting for age, education levels, and other factors.ConclusionAs the marker of endothelial dysfunction, the high perioperative UACR value may be linked to the postoperative delirium in elderly patients undergoing elective non‐cardiac surgery.