Higher serum PGE2 is a predicative biomarker for postoperative delirium following elective orthopedic surgery in elderly patients

Novel applications of sleep pharmacology as delirium therapeutics

Sleep-wake and circadian disruption (SCD) is a core feature of delirium. It has been hypothesized that SCD contributes to delirium pathogenesis; therefore, interventions that prevent or reverse SCD represent an array of promising opportunities in relation to delirium. This review explores the relationship between sleep-wake/circadian physiology and delirium pathophysiology with a focus on neurotransmitter systems. Across potential targets aimed at preventing or treating delirium, three broad approaches are considered: 1. Pharmacological mechanisms that contribute to physiological sleep may preserve or restore next-day cognition in patients with or at risk for delirium (e.g., alpha 2 agonists, dopamine 2 antagonists, serotonin 2 A antagonists, dual orexin receptor antagonists, or GHB agonists); 2. Pharmacological mechanisms that promote wakefulness during the day may combat hypoactive delirium (e.g., adenosine 2 A antagonists, dopamine transporter antagonists, orexin agonists, histamine 3 antagonists); and 3. Melatonergic and other circadian interventions could strengthen the phase or amplitude of circadian rhythms and ensure appropriately entrained timing in patients with or at risk for delirium (e.g., as informed by a person's preexisting circadian phase).

Influence of Intraoperative Pain Management on Postoperative Delirium in Elderly Patients: A Prospective Single-Center Randomized Controlled Trial

INTRODUCTION

Intraoperative analgesia and sedation are closely related to postoperative delirium. Depth of sedation based on bispectral index (BIS) guidance has been shown to reduce the occurrence of postoperative delirium (POD). However, the correlation between intraoperative analgesia levels and POD is unclear. The aim of this study was to investigate the effect of intraoperative analgesic management guided by the nociceptive stimulus index (NOX) on postoperative delirium.

METHODS

In this prospective single-center randomized controlled study, elderly patients aged 65 and above, who are scheduled to undergo unilateral total knee arthroplasty (TKA), were allocated into two groups: the routine monitoring group (group R), which solely monitored patient sedation levels using BIS; and the NOX monitoring group (group N), which monitored patient analgesic levels using NOX based on BIS-monitored sedation levels. The primary outcome was the incidence of postoperative delirium within 3 days after surgery, using the confusion assessment method (CAM).

RESULTS

From May 2022 to December 2022, a total of 240 patients were randomized; 12 were excluded because of failure to meet experimental conditions or were lost to follow-up. Patients in group N had a lower incidence rate (%) of POD on the first day compared to those in group R (8 (7%) vs 18 (16%), P = 0.041). The dosage of remifentanil administered in group N was significantly higher than that in group R (927.07 ± 268.09 vs 882.32 ± 187.91 mg, P = 0.002).

CONCLUSIONS

Appropriate intraoperative analgesia guided by NOX is associated with POD. When sedation levels were consistent, the incidence of POD was significantly reduced in older patients with NOX-guided analgesic management during unilateral TKA surgery.

Accumulating the key proteomic signatures associated with delirium: Evidence from systematic review

Delirium is a severe neuropsychiatric illness that occurs frequently in intensive care and postoperative units which results in prolonged hospital stays and increases patient's mortality and morbidity rates. This review focused on accumulating the common key proteomic signatures significantly associated with delirium. We carried out a systematic literature review of studies on delirium proteomic biomarkers published between 1st January 2000 and 31st December 2023 from the following electronic bibliographic databases including PubMed, Scopus, and EBSCOhost (CINAHL, Medline). A total of 1746 studies were identified and reviewed, and 78 studies were included in our review. The PRISMA guidelines, the PEO framework, and JBI quality assessment method were followed in this review to maintain the inclusion and exclusion criteria and risk of bias assessment. Most of the included studies were of the cohort (68%) and case-control (23%) design. We have accumulated a total of 313 proteins or gene encoded proteins of which 189 were unique. Among the unique proteins, we focused on the top 13 most investigated proteins (IL-6, CRP, IL-8, S100B, IL-10, TNF-a, IL-1b, Cortisol, MCP-1, GFAP, IGF-1, IL-1ra, and NFL) that are significantly associated with delirium. Most of these are cytokines and inflammatory proteins indicating a strong interconnection with delirium. There was remarkable inconsistency among the studies in reporting the specific potential proteomic biomarker. No single proteomic biomarker can be solely used to diagnose and predict delirium. The current review provides a rationale for further molecular investigation of delirium-related proteomic biomarkers. Also, it's recommended to conduct further in-depth molecular research to decipher drug target biomolecules for potential prognostic, diagnostic, and therapeutic development against delirium.

The association between the fibrinogen-to-albumin ratio and delirium after deep brain stimulation surgery in Parkinson's disease

Introduction

Postoperative delirium (POD) remains one of the most prevalent neuropsychiatric complications after deep brain stimulation (DBS) surgery. The fibrinogen-to-albumin ratio (FAR) has been shown to significantly correlate with the prognosis of many diseases related to inflammation. However, the association between FAR and POD remains unclear. We aimed to explore the association between POD and FAR in patients with Parkinson's disease (PD) undergoing DBS surgery.

Methods

Patients with PD who underwent DBS surgery in our hospital were included in this retrospective study. FAR was calculated from the blood sample collected on admission. The association between baseline FAR and delirium after surgery was assessed by binary logistic regression analysis, interaction analysis, and stratified analyses.

Results

Of 226 patients, 37 (16.4%) suffered from delirium after surgery. The average age of the participants was 63.3 ± 7.2 years, and 51.3% were male patients. Multivariate logistic regression analysis indicated that patients in the highest FAR tertile had a higher risk of POD compared with patients in the lowest FAR tertile (OR = 3.93, 95% CI: 1.24 ~ 12.67). Subgroup analysis demonstrated that FAR and the preoperative Mini-Mental State Examination score (p = 0.013) had an association with delirium after surgery.

Conclusion

Our data suggest that a higher preoperative FAR was significantly associated with delirium after DBS surgery. FAR on admission is a useful candidate biomarker to identify patients with PD who are at a high risk of delirium following DBS surgery.

The Potential Value of Systemic Inflammation Response Index on Delirium After Hip Arthroplasty Surgery in Older Patients: A Retrospective Study

Purpose

To explore the relationship between the systemic inflammation response index (SIRI) and postoperative delirium (POD) in older patients with hip arthroplasty surgery.

Patients and Methods

Older patients who underwent elective hip arthroplasty surgery were included in this retrospective study. SIRI, neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) were collected from blood routine examination at admission. Binary logistic regression analysis was performed to evaluate the association between SIRI levels and POD was analyzed.

Results

Ultimately, 116 older patients who met the inclusion criteria were assessed. Thirty-four (29%) of 116 patients diagnosed with POD were defined as the POD group, and the rest consisted of the Non-POD group. Compared with non-POD patients, POD patients showed significantly higher levels of SIRI (P < 0.001) and NLR (P = 0.002) at admission. There was no significance in the levels of PLR between two groups. SIRI was independently associated with the occurrence of POD in multivariate logistic regression analysis [odds ratio (OR) = 3.34, 95% confidence interval (95% CI) = 1.26-8.85, P = 0.016]. Receiver operating characteristic curve analysis indicated that SIRI with an optimal cutoff value of 0.987 predicted the POD with a sensitivity of 88.2% and specificity of 74.4%, and the area under the curve was 0.82 (95% CI, 0.74-0.90, P < 0.01).

Conclusion

Preoperative SIRI and NLR levels in the blood are associated with the occurrence of POD. Moreover, preoperative SIRI level is a useful candidate biomarker to identify delirium after elective hip arthroplasty surgery in older patients.

15-lipoxygenase and cyclooxygenase expression profile and their related modulators in COVID-19 infection

BACKGROUND

The role of the lipoxygenase (LOX) and cyclooxygenase (COX) enzymes in maintaining cellular homeostasis and regulating immune responses promoted us in this study to analyze the pattern of changes in 15-lipoxygenase and cyclooxygenase isoforms and their related cytokines in SARS-CoV-2 infection.

METHODS

15-LOX-1, 15-LOX-2, COX-1 and COX-2 gene expression levels were determined using qRT-PCR in nasopharynx specimens from patients with severe [N = 40] and non-severe [N = 40] confirmed SARS-CoV-2 infections and healthy controls. Circulating levels of lL-6, lL-10, PGE2, and IFN-γ were measured in patients and healthy controls using ELISA assay. The associations between the measured variables and the patient's clinic-pathological characteristics were assessed for all groups.

RESULTS

The expression level of 15-LOX-1 was elevated significantly in male patients with severe infection; although female patients showed a different expression profile. 15-LOX-2 expression level was considerably increased in male patients with severe infection; while changes in its expression remained inconclusive in female patients. The relationship between 15-LOX expression and the male gender was prominent. Both COX isoforms expression showed elevation in male and female patients that were correlated with disease severity. The simultaneous increase in lL-6, PGE2 and IFN-γ levels also decrease in lL-10 in patients with severe infection indicating the possible regulatory network related to the COX and 15-LOX enzymes in the output of the SARS-CoV-2 infection.

CONCLUSION

The results of this study determined the pattern of possible changes in key enzymes of prostaglandin and eicosanoids synthesis pathway and their mediators, which can be helpful in mapping the SARS-CoV-2 pathogenicity and pharmaceutical approaches.