Perioperative predictors of delirium and incidence factors in adult patients post cardiac surgery

Predictive value of cumulative SII for MACE in STEMI patients after PCI

The systemic immune-inflammation index (SII) has been used effectively to effectively assess the prognosis of patients with a variety of diseases. But few evidence on the relationship between SII and long-term prognosis of myocardial infarction. We thus aimed to evaluate the relationships of cumulative exposure to SII and its accumulation time course with major adverse cardiovascular events (MACE) events in patients with acute myocardial infarction after percutaneous coronary intervention. To evaluate the predictive value of SII in MACE events in patients with acute myocardial infarction. A total of 480 patients with acute ST-elevation myocardial infarction who underwent emergency coronary angiography at the Department of Cardiology, Affiliated Hospital of Hebei University from August 2022 to August 2023 were enrolled in this study. Eighteen patients were lost to follow-up, with a loss rate of 3.8%. Time-weighted cumulative SII was calculated as the weighted sum of the mean SII value for each time interval, then normalized by total exposure duration, the exposure duration was from hospitalization to 1-year follow-up. Duration of high SII exposure was defined as the duration with high SII and ranged from hospitalization to 1-year follow-up. The time course of SII accumulation was categorized by the combination of time-weighted cumulative SII < or ≥ median and SII slope. At 1-year follow-up, after adjusting for potential confounders, the time-weighted cumulative SII was divided into 2 groups. The S2 group which is above the median had a higher risk of MACE (hazard ratio, 1.090; 95% confidence interval 1.035-1.149), the high time-weighted cumulative SII group with a positive slope had a higher risk of MACE (hazard ratio, 4.096; 95% confidence interval 1.851-9.065). Long-term cumulative exposure to SII increases the risk of MACE in patients with acute ST-elevation myocardial infarction undergoing coronary angiography, and late high SII results in a higher risk of MACE events at the same time-weighted cumulative SII, underscoring the importance of late inflammation control.

Systematic literature review on early detection of postoperative delirium in adult patients after cardiac surgery

BACKGROUND

Postoperative delirium (POD) is a cognitive decline and attention deficit that can occur in patients after cardiac surgery. Despite extensive research identifying the risk factors, POD often remains undiagnosed and untreated in medical settings. Therefore, this systematic literature review (SLR) aimed to summarize the available studies on early POD identification in patients following cardiovascular surgery.

METHOD

Data were obtained from Scopus, PubMed, and the Cochrane International database. The search strategy was designed to identify articles published between January 2000 and January 2024. The keywords and medical subject heading (MeSH) terms used in the search included "postoperative delirium," "cardiac surgery," "early detection," and "risk factors." Studies were included if they met the following criteria: (1) focused on adult patients undergoing cardiac surgery; (2) examined methods for the early identification or prediction of POD; and (3) provided statistical analyses or clinical outcomes related to POD. The exclusion criteria were: studies on non-cardiac surgeries, pediatric populations, or those without clear methodological details.

RESULTS

Seven of the examined studies highlighted high-risk variables (individual characteristics, underlying diseases, and treatment methods) and typical symptoms as crucial components for early POD diagnosis. However, the diagnostic criteria and evaluation methodologies needed to be more consistent, and there was no consensus regarding the most efficient early detection approaches.

CONCLUSION

These findings underscore the need for standardized diagnostic criteria and evaluation methods for the early detection of POD in patients undergoing cardiovascular surgery. Evidence-based recommendations are necessary to enhance early diagnosis and treatment of POD in this population.

Neutrophil to Lymphocyte Ratio and Periprosthetic Joint Infection: A Systematic Review and Meta-Analysis

BACKGROUND

The neutrophil-to-lymphocyte ratio (NLR) has shown promising results as a diagnostic tool for periprosthetic joint infection (PJI) after total joint arthroplasty. We conducted a systematic review and meta-analysis to determine the utility of NLR in the diagnosis of PJI.

METHODS

We searched PubMed, Scopus, and Web of Science from inception up to 2022 and evaluated the quality of the included literature.

RESULTS

Based on the 12 eligible studies, NLR levels were significantly higher in patients who had PJI compared to those who had aseptic loosening (standard mean difference (SMD) = 1.05, 95% Confidence Interval (CI) = 0.71 to 1.40, P < .001). In the subgroup analysis according to type of PJI, NLR levels were significantly higher in patients who had either acute (SMD = 1.04, 95% CI = 0.05 to 2.03, P < .001) or chronic PJI (SMD = 1.08, 95% CI = 0.55 to 1.61, P < .001), compared to those who had aseptic loosening. According to type of arthroplasty, NLR levels were significantly higher in patients who had either total knee arthroplasty (SMD = 1.81, 95% CI = 1.48 to 2.13, P < .001) or total hip arthroplasty (SMD = 1.76, 95% CI = 1.54 to 1.98, P < .001) compared to aseptic loosening. The pooled sensitivity of the 12 studies was 0.73 (95% CI, 0.65 to 0.79), and the pooled specificity was 0.75 (95% CI, 0.71 to 0.78). The pooled positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio of NLR were 2.94 (95% CI = 2.44 to 3.54), 0.35 (95% CI = 0.27 to 0.46), and 8.26 (95% CI = 5.42 to 12.58), respectively.

CONCLUSION

In summary, this meta-analysis indicates that NLR is a reliable marker in the diagnosis of PJI.

Neutrophil to lymphocyte ratio and platelet to lymphocyte ratio as prognostic predictors for delirium in critically ill patients: a systematic review and meta-analysis

INTRODUCTION

In this systematic review and meta-analysis, we aim to analyze the current literature to evaluate neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) values among critically ill patients who develop delirium as compared to those who do not.

METHODS

PubMed, Web of Science, and Scopus were used to conduct a systematic search for relevant publications published before June 12, 2022. The Newcastle-Ottawa scale was used for quality assessment. Because a significant level of heterogeneity was found, we used the random-effects model to generate pooled effects.

RESULTS

Twenty-four studies including 11,579 critically ill patients, of whom 2439 were diagnosed with delirium, were included in our meta-analysis. Compared with the non-delirious group, the delirious group's NLR levels were significantly higher (WMD = 2.14; CI 95% = 1.48-2.80, p < 0.01). In the subgroup analysis according to the type of critical condition, the NLR levels in patients of delirious group were significantly more than those of non-delirious group in studies on POD, PSD and PCD (WMD = 1.14, CI 95% = 0.38-1.91, p < 0.01, WMD = 1.38, CI 95% = 1.04-1.72, p < 0.001, and WMD = 4.22, CI 95% = 3.47-4.98, p < 0.001, respectively). However, compared with the non-delirious group, the delirious group's PLR levels were not significantly different (WMD = 1.74; CI 95% = -12.39-15.86, p = 0.80).

CONCLUSION

Our findings support NLR to be a promising biomarker that can be readily integrated into clinical settings to aid in the prediction and prevention of delirium.

Common Biomarkers Associated with Delirium in Hospitalized Patients with COVID-19 at the Epicentre of Turkish Coronavirus Outbreak: A Case-Control Study

Introduction

To investigate the differences in biochemical characteristics between Coronavirus Disease 2019 (COVID-19) patients with and without delirium in non-intensive care (IC) COVID-19 units was aimed.

Methods

This study was designed as an observational, single-centered, and case-control study consisting of 43 delirious patients and matched 45 non-delirious patients admitted to non-IC COVID-19 units. Delirium was diagnosed by a consultant psychiatrist according to the DSM-5 delirium diagnostic criteria. Independent variables such as laboratory tests at the time of admission, clinical features, and patient characteristics were obtained from electronic medical records by researchers. In the primary analyses, binomial logistic regression models were used to investigate the factors associated with delirium, which was identified as the outcome variable. Multivariate logistic models were then adjusted for potential confounding factors, including age, gender, history of neurocognitive disorders and Charlson Comorbidity Index (CCI).

Results

We observed higher levels of urea, d-dimer, troponin-T, proB-type natriuretic peptide, and CCI in patients with delirium compared to patients without delirium. We also observed lower levels of estimated glomerular filtration rate (eGFR), serum albumin, and O₂ saturation and a decrease in the length of stay at the hospital. After adjusting for confounding factors such as gender, age, and comorbidity, we found that urea (adjusted estimate=0.015; 95% Confidence Interval [CI]=0.058-0.032, P=0.039), urea/creatinine ratio (adjusted estimate=0.008; 95% CI=0.002-0.013, P=0.011), and troponin-T (adjusted estimate=0.066; 95% CI=0.014-0.118, P=0.014) were independent biomarkers associated with delirium.

Conclusion

Delirium is associated with higher urea levels and urea/creatinine ratios in COVID-19 patients. In addition, the relationship between troponin-T and delirium may help understand the potential link between the brain and the heart in COVID-19. Additional multi-centred studies with larger sample sizes are needed to generalise these results.

Prediction model for delirium in patients with cardiovascular surgery: development and validation

BACKGROUND

The aim of this study was to construct a nomogram model for discriminating the risk of delirium in patients undergoing cardiovascular surgery.

METHODS

From January 2017 to June 2020, we collected data from 838 patients who underwent cardiovascular surgery at the Affiliated Hospital of Nantong University. Patients were randomly divided into a training set and a validation set at a 5:5 ratio. A nomogram model was established based on logistic regression. Discrimination and calibration were used to evaluate the predictive performance of the model.

RESULTS

The incidence of delirium was 48.3%. A total of 389 patients were in the modelling group, and 449 patients were in the verification group. Logistic regression analysis showed that CPB duration (OR [Formula: see text] 1.004, 95% CI: 1.001-1.008, [Formula: see text] 0.018), postoperative serum sodium (OR [Formula: see text] 1.112, 95% CI: 1.049-1.178, [Formula: see text] 0.001), age (OR [Formula: see text] 1.027, 95% CI: 1.006-1.048, [Formula: see text] 0.011), and postoperative MV (OR [Formula: see text] 1.019, 95% CI: 1.008-1.030, [Formula: see text] 0.001) were independent risk factors. The results showed that AUC[Formula: see text] was 0.712 and that the 95% CI was 0.661-0.762. The Hosmer-Lemeshow goodness of fit test showed that the predicted results of the model were in good agreement with the actual situation ([Formula: see text] 6.200, [Formula: see text] 0.625). The results of verification showed that the AUC[Formula: see text] was 0.705, and the 95% CI was 0.657-0.752. The Hosmer-Lemeshow goodness of fit test results were [Formula: see text] 8.653 and [Formula: see text] 0.372, indicating that the predictive effect of the model is good.

CONCLUSIONS

The establishment of the model provides accurate and objective assessment tools for medical staff to start preventing postoperative delirium in a purposeful and focused manner when a patient enters the CSICU after surgery.

Outcomes of postoperative delirium in patients undergoing cardiac surgery: A systematic review and meta-analysis

Background

Postoperative delirium (POD) is an acute brain dysfunction that is frequently observed in patients undergoing cardiac surgery. Increasing evidence indicates POD is related to higher mortality among cardiac surgical patients, but the results remain controversial. Moreover, a quantitative evaluation of the influence of POD on hospital days, intensive care unit (ICU) time, and mechanical ventilation (MV) time has not been performed.

Objective

This study aimed to evaluate the correlation between POD and outcomes in patients undergoing cardiac surgery by a systematic review and meta-analysis.

Materials and methods

A total of 7 electronic databases (Cochrane Library, PubMed, EMBASE, CINAHL Complete, MEDLINE, Wan-fang database, and China National Knowledge Infrastructure) were searched from January 1980 to July 20, 2021, with language restrictions to English and Chinese, to estimate the impact of the POD on outcome in patients who underwent cardiac surgery. The meta-analysis was registered with PROSPERO (Registration: CRD42021228767).

Results

Forty-two eligible studies with 19785 patients were identified. 3368 (17.0%) patients were in the delirium group and 16417 (83%) were in the non-delirium group. The meta-analysis showed that compared to patients without POD, patients with POD had 2.77-fold higher mortality (OR = 2.77, 95% CI 1.86-4.11, P < 0.001), 5.70-fold higher MV (>24h) rate (OR = 5.70, 95% CI 2.93-11.09, P < 0.001); and longer MV time (SMD = 0.83, 95% CI 0.57-1.09, P < 0.001), ICU time (SMD = 0.91, 95% CI 0.60-1.22, P < 0.001), hospital days (SMD = 0.62, 95% CI 0.48-0.76, P < 0.001).

Conclusion

The synthesized evidence suggests that POD is causally related to the increased risk of mortality, prolonged length of ICU and hospital stay, and a longer duration of MV time. Future research should focus on the interventions for POD, to reduce the incidence.

Systematic review registration

[www.crd.york.ac.uk/PROSPERO], identifier [CRD42021228767].

Challenges in the Detection of Clinically Useful Biomarkers for the Diagnosis of Delirium in Older People in the Emergency Department-A Case-Control Study

Background: The identification of biomarkers associated with delirium in the emergency department could contribute to the understanding, prediction and diagnosis of this disorder. The present study was carried out to identify biomarkers included in easily and quickly obtained standard blood examinations in older patients with delirium in the emergency department. Methods: A case–control study was carried out in the emergency department of Francesc de Borja Hospital (Gandía, Valencia, Spain). Older adults (≥65 years of age) diagnosed with delirium (n = 128) were included. Cases due to alcohol or substance abuse were excluded. Controls were selected on a randomized basis from the remaining patients (n = 128). All laboratory test parameters included in the routine blood and urine tests of the emergency department were collected. Results: The mean age of the patients was 81.24 ± 7.51 years, and 56.2% were males, while the mean age of the controls was 78.97 ± 7.99 years, and 45.3% were males. Significant differences were found between the cases and controls in relation to the following parameters: urea 43 (32–58) mg/dL versus 50 (37–66) mg/dL, respectively; neutrophils 69.6 (62.05–78.75)% versus 75.5 (65.1–83.2)%; monocytes 8.7 (7–10.4)% versus 7.6 (5.5–9.2)%; platelets 213 (159–266) × 10⁹/L versus 224 (182–289) × 10⁹/L; neutrophil–lymphocyte ratio 3.88 (2.45–7.07) versus 5 (2.75–8.83); platelet–lymphocyte ratio 281.4 (210–360) versus 357.1 (257.8–457.1); and mean platelet volume 10.6 (10–11.5) fl versus 10.4 (9.67–10.9) fl. Although the mean values were above desirable levels in both groups, they were higher for most parameters in the control group. No significant differences were observed in C-reactive protein concentration (9.99 (1.69–51) mg/L versus 12.3 (3.09–65.97) mg/L). Conclusions: The identification of delirium biomarkers poses difficulties due to the urgent nature of the disorders found in older people admitted to the emergency department. Research in this field is needed, since it would allow early identification and treatment of delirium.

Assessment of preoperative frailty and identification of patients at risk for postoperative delirium in cardiac intensive care units: a prospective observational study

BACKGROUND

Postoperative delirium (POD) is a common complication that may occur from 24 to 72 h after cardiac surgery. Frailty is a chronic syndrome that leads to a decline in physiological reserve and to disability. The associations between frailty and POD are unclear.

AIMS

To investigate associations between POD and frailty in patients undergoing cardiac surgery and to analyse predictors of POD.

METHODS AND RESULTS

Convenience sampling was used to recruit 152 patients who underwent cardiac surgery in two medical centres in northern Taiwan. Preoperative frailty in these patients was evaluated using Fried's frailty phenotype. Delirium in patients was assessed from postoperative day 1 to day 5 using the confusion assessment method for intensive care units. A total of 152 patients who underwent cardiac surgery included 68 (44.74%) prefrail patients and 21 (13.81%) patients with frailty after the surgery. Ten patients (6.58%) developed delirium after cardiac surgery. The occurrence of delirium peaked at postoperative day 2, and the average duration of delirium was 3 days. A case-control comparison revealed a significant correlation between preoperative frailty and POD. Significant predictors of POD in patients undergoing cardiac surgery included the European System for Cardiac Operative Risk Evaluation II, preoperative arrhythmia, and preoperative anxiety and depression.

CONCLUSION

Preoperative frailty was correlated with POD. Preoperative arrhythmia, anxiety, and depression are predictors of POD. Nurses should perform preoperative assessments of surgical risk and physiological and psychological conditions of patients undergoing cardiac surgery and monitor the occurrence of POD.

Postoperative delirium after cardiac surgery of elderly patients as an independent risk factor for prolonged length of stay in intensive care unit and in hospital

Background

Postoperative delirium (POD) is a relevant and underdiagnosed complication after cardiac surgery that is associated with increased intensive care unit (ICU) and hospital length of stay (LOS). The aim of this subgroup study was to compare the frequency of tested POD versus the coded International Statistical Classification of Diseases and Related Health Problems (ICD) diagnosis of POD and to evaluate the influence of POD on LOS in ICU and hospital.

Methods

254 elective cardiac surgery patients (mean age, 70.5 ± 6.4 years) at the University Hospital Bonn between September 2018 and October 2019 were evaluated. The endpoint tested POD was considered positive, if one of the tests Confusion Assessment Method for ICU (CAM-ICU) or Confusion Assessment Method (CAM), 4 'A's Test (4AT) or Delirium Observation Scale (DOS) was positive on one day.

Results

POD occurred in 127 patients (50.0%). LOS in ICU and hospital were significantly different based on presence (ICU 165.0 ± 362.7 h; Hospital 26.5 ± 26.1 days) or absence (ICU 64.5 ± 79.4 h; Hospital 14.6 ± 6.7 days) of POD (p < 0.001). The multiple linear regression showed POD as an independent predictor for a prolonged LOS in ICU (48%; 95%CI 31–67%) and in hospital (64%; 95%CI 27–110%) (p < 0.001). The frequency of POD in the study participants that was coded with the ICD F05.0 and F05.8 by hospital staff was considerably lower than tests revealed by the study personnel.

Conclusion

Approximately 50% of elderly patients who underwent cardiac surgery developed POD, which is associated with an increased ICU and hospital LOS. Furthermore, POD is highly underdiagnosed in clinical routine.

Urea-Creatinine Ratio (UCR) After Aneurysmal Subarachnoid Hemorrhage: Association of Protein Catabolism with Complication Rate and Outcome

OBJECTIVE

The urea-creatinine ratio (UCR) has been proposed as potential biomarker for critical illness-associated catabolism. Its role in the context of aneurysmal subarachnoid hemorrhage (aSAH) remains to be elucidated, which was the aim of the present study.

METHODS

We enrolled 66 patients with aSAH with normal renal function and 36 patients undergoing elective cardiac surgery as a control group for the effects of surgery. In patients with aSAH, the predictive or diagnostic value of early (day 0-2) and critical (day 5-7) UCRs was assessed with regard to delayed cerebral ischemia (DCI), DCI-related infarction, and clinical outcome after 12 months.

RESULTS

Preoperatively, UCR was similar both groups. Within 2 days postoperatively, UCRs increased significantly in patients in the elective cardiac surgery group (P < 0.001) but decreased back to baseline on day 5-7 (P = 0.245), whereas UCRs in patients with aSAH increased to significantly greater levels on day 5-7 (P = 0.028). Greater early or critical UCRs were associated with poor clinical outcomes (P = 0.015) or DCI (P = 0.011), DCI-related infarction (P = 0.006), and poor clinical outcomes (P < 0.001) respectively. In multivariate analysis, there was an independent association between greater early UCRs and poor clinical outcomes (P = 0.026).

CONCLUSIONS

In this exploratory study of UCR in the context of aSAH, greater early values were predictive for a poor clinical outcome after 12 months, whereas greater critical values were associated with DCI, DCI-related infarctions, and poor clinical outcomes. The clinical implications as well as the pathophysiologic relevance of protein catabolism should be explored further in the context of aSAH.

Neutrophil-to-lymphocyte Ratio and Platelet-to-lymphocyte Ratio as Biomarkers for Cardiovascular Surgery Procedures: A Literature Review

BACKGROUND

Neutrophil-to-lymphocyte ratio (NLR) and the platelet-to-lymphocyte ratio (PLR) have been studied so far as prognostic factors of cardiovascular diseases. Their role interplayed with endothelial inflammation has emerged as optimal predictors for major cardiovascular disease events and prognostic factors for post-procedural outcomes.

METHODS

A review of the current literature was undertaken to investigate the relationship between NLR and PLR with percutaneous, cardiac surgery, and vascular surgery procedures.

RESULTS

Our findings show that perioperative NLR and PLR levels are significantly correlated with patient morbidity and mortality rates.

CONCLUSION

These biomarkers have several attractive characteristics, as they are inexpensive and quickly available, and they can contribute to the early identification of patients at high risk for periprocedural adverse events.

Current Evidence Regarding Biomarkers Used to Aid Postoperative Delirium Diagnosis in the Field of Cardiac Surgery-Review

Postoperative cognitive disorders after cardiac surgery may manifest as postoperative delirium (POD) or later as postoperative cognitive dysfunction (POCD). The incidence of POD after cardiac surgery ranges from 16% to 73%. In contrast to POD, POCD is usually diagnosed after the discharge from hospital, with an incidence of 30 to 70% of cases, very often noticed only by close relative or friends, decreasing after six (20–30%) and twelve (15–25%) months after surgery. Perioperative cognitive disorders are associated with adverse short- and long-term effects, including increased morbidity and mortality. Due to the complexity of delirium pathomechanisms and the difficulties in the diagnosis, researchers have not yet found a clear answer to the question of which patient will be at a higher risk of developing delirium. The risk for POD and POCD in older patients with numerous comorbidities like hypertension, diabetes, and previous ischemic stroke is relatively high, and the predisposing cognitive profile for both conditions is important. The aim of this narrative review was to identify and describe biomarkers used in the diagnosis of delirium after cardiac surgery by presenting a search through studies regarding this subject, which have been published during the last ten years. The authors discussed brain-derived biomarkers, inflammation-related biomarkers, neurotransmitter-based biomarkers, and others. Work based on inflammation-related biomarkers, which are characterized by the low cost of implementation and the effectiveness of delirium diagnosis, seems to be the closest to the goal of discovering an inexpensive and effective marker. Currently, the use of a panel of tests, and not a single biomarker, brings us closer to the discovery of a test, or rather a set of tests ideal for the diagnosis of delirium after cardiac surgery.