Association between postoperative delirium and heart rate variability in the intensive care unit and readmissions and mortality in elderly patients with cardiovascular surgery.

This study aimed to investigate the relationship between heart rate variability (HRV), a parameter of the autonomic nervous system activity (ANSA), and postoperative delirium and postoperative events. This retrospective cohort study included elderly patients aged 65 years or older who were admitted to the intensive care unit (ICU) after cardiovascular surgery. ANSA was measured using HRV parameters for 1 h at daytime and 1 h at night-time before ICU discharge. The primary endpoint was the effect of HRV parameters and delirium on mortality and readmission rates within 1 year after discharge, and the secondary endpoint was the association between HRV parameters and delirium. Cox proportional hazards models were used to examine the association between HRV parameters and postoperative events by adjusting for delirium and pre and postoperative information. A total of 71 patients, 39 without delirium and 32 with delirium, met the inclusion criteria. The incidence of death and readmission within 1 year was significantly higher in the delirium group and in the group with higher daytime HF (high frequency power) and r-MSSD (square root of the squared mean of the difference of successive NN intervals), parameters of the parasympathetic nervous system activity (PNSA), than that in other groups. Furthermore, the delirium group had significantly higher HF and r-MSSD than the nondelirium group. Even after adjusting for confounding factors in the multivariate analysis, a trend of higher daytime HF and r-MSSD was observed, indicating a significant effect on the occurrence of combined events within 1 year of discharge. ICU delirium has been associated with higher daytime HF and r-MSSD, parameters of PNSA. ICU delirium was a prognostic factor, and increased daytime PNSA may worsen the prognosis of elderly patients after cardiovascular surgery.

Decreased activities of daily living at discharge predict mortality and readmission in elderly patients after cardiac and aortic surgery: A retrospective cohort study.

ABSTRACT: Recently, activities of daily living (ADL) were identified as a prognostic factor among elderly patients with heart disease; however, a specific association between ADL and prognosis after cardiac and aortic surgery is not well established. We aimed to clarify the impact of ADL capacity at discharge on prognosis in elderly patients after cardiac and aortic surgery.This retrospective cohort study included 171 elderly patients who underwent open operation for cardiovascular disease in a single center (median age: 74 years; men: 70%). We used the Barthel Index (BI) as an indicator for ADL. Patients were classified into 2 groups according to the BI at discharge, indicating a high (BI ≥ 85) or low (BI < 85) ADL status. All-cause mortality and unplanned readmission events were observed after discharge.Thirteen all-cause mortality and 44 all-cause unplanned readmission events occurred during the median follow-up of 365 days. Using Kaplan-Meier analysis, a low ADL status was determined to be significantly associated with all-cause mortality and unplanned readmission. In the multivariable Cox proportional hazard models, a low ADL status was an independent predictor of all-cause mortality and unplanned readmission after adjusting for age, sex, length of hospital stay, and other variables (including preoperative status, surgical parameter, and postoperative course).A low ADL status at discharge predicted all-cause mortality and unplanned readmission in elderly patients after cardiac and aortic surgery. A comprehensive approach from the time of admission to postdischarge to improve ADL capacity in elderly patients undergoing cardiac and aortic surgery may improve patient outcomes.

The modified water swallowing test score is the best predictor of postoperative pneumonia following extubation in cardiovascular surgery: A retrospective cohort study.

ABSTRACT: No guidelines have been established for the evaluation of swallowing function following extubation. The factors of bedside swallowing evaluations (BSEs) that are associated with the development of pneumonia have not been fully elucidated. This study aimed to retrospectively investigate the most appropriate measurements of BSEs for predicting pneumonia.The study subjects were 97 adults who underwent BSEs following cardiovascular surgery. Patients were divided into the pneumonia onset group (n = 21) and the non-onset group (n = 76). Patient characteristics, intraoperative characteristics, complications, BSE results, and postoperative progress were compared between the groups. BSEs were composed of consciousness level, modified water swallowing test (MWST) score, repetitive saliva swallowing test score, speech intelligibility score, and risk of dysphagia in the cardiac surgery score. Univariate and multivariate analyses with the BSE as the independent variable and pneumonia onset as the dependent variable were also performed to identify factors that predict pneumonia. For factors that became significant in univariate analysis, the incidence of pneumonia was shown using the Kaplan-Meier curve.No significant differences were found in patient characteristics, intraoperative characteristics, and complications between the 2 groups. The postoperative progress was significantly different between the 2 groups, the pneumonia-onset group had a significantly longer time until the start of oral intake and a significantly lower median value of Food Intake Level Scale at the time of discharge. According to univariate and multivariate analyses, MWST score was a significant factor for predicting the onset of pneumonia even after adjusting for patient characteristics and surgical factors, and the incidence of pneumonia increased approximately 3 times when the MWST score was 3 points or less.The MWST score after extubation in cardiovascular surgery was the strongest predictor of postoperative pneumonia in BSEs. Furthermore, the incidence of pneumonia increased approximately 3 times when the MWST score was 3 points or less. Predicting cases with a high risk of developing pneumonia allows nurses and attending physicians to monitor the progress carefully and take aggressive preventive measures.