Browsing by Subject "Postoperative"

Now showing 1 - 5 of 5
  • Thumbnail Image
    Item
    Association between plasma tau and postoperative delirium incidence and severity: a prospective observational study
    (Elsevier, 2021) Ballweg, Tyler; White, Marissa; Parker, Margaret; Casey, Cameron; Bo, Amber; Farahbakhsh, Zahra; Kayser, Austin; Blair, Alexander; Lindroth, Heidi; Pearce, Robert A.; Blennow, Kaj; Zetterberg, Henrik; Lennertz, Richard; Sanders, Robert D.; Medicine, School of Medicine
    Background: Postoperative delirium is associated with increases in the neuronal injury biomarker, neurofilament light (NfL). Here we tested whether two other biomarkers, glial fibrillary acidic protein (GFAP) and tau, are associated with postoperative delirium. Methods: A total of 114 surgical patients were recruited into two prospective biomarker cohort studies with assessment of delirium severity and incidence. Plasma samples were sent for biomarker analysis including tau, NfL, and GFAP, and a panel of 10 cytokines. We determined a priori to adjust for interleukin-8 (IL-8), a marker of inflammation, when assessing associations between biomarkers and delirium incidence and severity. Results: GFAP concentrations showed no relationship to delirium. The change in tau from preoperative concentrations to postoperative Day 1 was greater in patients with postoperative delirium (P<0.001) and correlated with delirium severity (ρ=0.39, P<0.001). The change in tau correlated with increases in IL-8 (P<0.001) and IL-10 (P=0.0029). Linear regression showed that the relevant clinical predictors of tau changes were age (P=0.037), prior stroke/transient ischaemic attack (P=0.001), and surgical blood loss (P<0.001). After adjusting for age, sex, preoperative cognition, and change in IL-8, tau remained significantly associated with delirium severity (P=0.026). Using linear mixed effect models, only tau (not NfL or IL-8) predicted recovery from delirium (P<0.001). Conclusions: The change in plasma tau was associated with delirium incidence and severity, and resolved over time in parallel with delirium features. The impact of this putative perioperative neuronal injury biomarker on long-term cognition merits further investigation.
  • Thumbnail Image
    Item
    Cohort study into the neural correlates of postoperative delirium: the role of connectivity and slow-wave activity
    (Elsevier, 2020-07) Tanabe, Sean; Mohanty, Rosaleena; Lindroth, Heidi; Casey, Cameron; Ballweg, Tyler; Farahbakhsh, Zahra; Krause, Bryan; Prabhakaran, Vivek; Banks, Matthew I.; Sanders, Robert D.; Medicine, School of Medicine
    Background: Delirium frequently affects older patients, increasing morbidity and mortality; however, the pathogenesis is poorly understood. Herein, we tested the cognitive disintegration model, which proposes that a breakdown in frontoparietal connectivity, provoked by increased slow-wave activity (SWA), causes delirium. Methods: We recruited 70 surgical patients to have preoperative and postoperative cognitive testing, EEG, blood biomarkers, and preoperative MRI. To provide evidence for causality, any putative mechanism had to differentiate on the diagnosis of delirium; change proportionally to delirium severity; and correlate with a known precipitant for delirium, inflammation. Analyses were adjusted for multiple corrections (MCs) where appropriate. Results: In the preoperative period, subjects who subsequently incurred postoperative delirium had higher alpha power, increased alpha band connectivity (MC P<0.05), but impaired structural connectivity (increased radial diffusivity; MC P<0.05) on diffusion tensor imaging. These connectivity effects were correlated (r2=0.491; P=0.0012). Postoperatively, local SWA over frontal cortex was insufficient to cause delirium. Rather, delirium was associated with increased SWA involving occipitoparietal and frontal cortex, with an accompanying breakdown in functional connectivity. Changes in connectivity correlated with SWA (r2=0.257; P<0.0001), delirium severity rating (r2=0.195; P<0.001), interleukin 10 (r2=0.152; P=0.008), and monocyte chemoattractant protein 1 (r2=0.253; P<0.001). Conclusions: Whilst frontal SWA occurs in all postoperative patients, delirium results when SWA progresses to involve posterior brain regions, with an associated reduction in connectivity in most subjects. Modifying SWA and connectivity may offer a novel therapeutic approach for delirium.
  • Thumbnail Image
    Item
    Contrast-Enhanced Ultrasound Versus Doppler Ultrasound for Detection of Early Vascular Complications of Pancreas Grafts
    (American Roentgen Ray Society, 2020-11) Swensson, Jordan; Hill, Danielle; Tirkes, Temel; Fridell, Jonathan; Patel, Aashish; Radiology and Imaging Sciences, School of Medicine
    OBJECTIVE. The purpose of this study is to compare conventional duplex ultrasound and contrast-enhanced ultrasound (CEUS) for identifying vascular abnormalities in pancreas allografts in the immediate posttransplant setting. Identification of pancreas allografts at risk of failure may impact patient care because early intervention for vascular insufficiency can lead to graft salvage. MATERIALS AND METHODS. Two radiologists who were blinded to patient outcomes performed a retrospective analysis of the postoperative Doppler ultrasound and CEUS images of 34 pancreas grafts from transplants performed between 2017 and 2019. A total of 28 patients who did not require surgical reexploration were considered the control group. Six patients had surgically proven arterial or venous abnormalities on surgical reexploration. Each radiologist scored grafts as having normal or abnormal vascularity on the basis of image sets obtained using Doppler ultrasound only and CEUS only. Comparisons of both the diagnostic performance of each modality and interobserver agreement were performed. RESULTS. Both readers showed that CEUS had increased sensitivity for detecting vascular abnormalities (83.3% for both readers) compared with Doppler ultrasound (66.7% and 50.0%). For both readers, the specificity of CEUS was similar to that of Doppler imaging (81.6% and 78.9% for reader 1 and reader 2 versus 76.3% and 84.2% for reader 1 and reader 2). For both readers, the negative predictive value of CEUS was higher than that of Doppler ultrasound (96.9% and 96.8% for reader 1 and reader 2 versus 93.5% and 91.4% for reader 1 and reader 2). Interobserver agreement was higher for CEUS than for Doppler ultrasound (κ = 0.54 vs κ = 0.28). CONCLUSION. CEUS may provide radiologists and surgeons with a means of timely and effective evaluation of pancreas graft perfusion after surgery, and it may help identify grafts that could benefit from surgical salvage.
  • Thumbnail Image
    Item
    Development and Validation of a Routine Electronic Health Record-Based Delirium Prediction Model for Surgical Patients Without Dementia: Retrospective Case-Control Study
    (JMIR, 2025-01-09) Holler, Emma; Ludema, Christina; Ben Miled, Zina; Rosenberg, Molly; Kalbaugh, Corey; Boustani, Malaz; Mohanty, Sanjay; Surgery, School of Medicine
    Background: Postoperative delirium (POD) is a common complication after major surgery and is associated with poor outcomes in older adults. Early identification of patients at high risk of POD can enable targeted prevention efforts. However, existing POD prediction models require inpatient data collected during the hospital stay, which delays predictions and limits scalability. Objective: This study aimed to develop and externally validate a machine learning-based prediction model for POD using routine electronic health record (EHR) data. Methods: We identified all surgical encounters from 2014 to 2021 for patients aged 50 years and older who underwent an operation requiring general anesthesia, with a length of stay of at least 1 day at 3 Indiana hospitals. Patients with preexisting dementia or mild cognitive impairment were excluded. POD was identified using Confusion Assessment Method records and delirium International Classification of Diseases (ICD) codes. Controls without delirium or nurse-documented confusion were matched to cases by age, sex, race, and year of admission. We trained logistic regression, random forest, extreme gradient boosting (XGB), and neural network models to predict POD using 143 features derived from routine EHR data available at the time of hospital admission. Separate models were developed for each hospital using surveillance periods of 3 months, 6 months, and 1 year before admission. Model performance was evaluated using the area under the receiver operating characteristic curve (AUROC). Each model was internally validated using holdout data and externally validated using data from the other 2 hospitals. Calibration was assessed using calibration curves. Results: The study cohort included 7167 delirium cases and 7167 matched controls. XGB outperformed all other classifiers. AUROCs were highest for XGB models trained on 12 months of preadmission data. The best-performing XGB model achieved a mean AUROC of 0.79 (SD 0.01) on the holdout set, which decreased to 0.69-0.74 (SD 0.02) when externally validated on data from other hospitals. Conclusions: Our routine EHR-based POD prediction models demonstrated good predictive ability using a limited set of preadmission and surgical variables, though their generalizability was limited. The proposed models could be used as a scalable, automated screening tool to identify patients at high risk of POD at the time of hospital admission.
  • Thumbnail Image
    Item
    Hydrocolloid dressing versus conventional wound care after dermatologic surgery
    (Elsevier, 2021-12-21) Holmes, Samantha P.; Rivera, Sydney; Hooper, Perry B.; Slaven, James E.; Que, Syril Keena T.; Medicine, School of Medicine
    Background: Hydrocolloid dressings (HCD) are helpful in chronic wound care, but research is limited in acute postoperative wounds. HCD can potentially be incorporated into a simplified wound care regimen after excisional surgeries. Objective: To examine whether a one-time HCD application after dermatologic surgery results in greater patient satisfaction and improved postoperative outcomes compared with conventional daily dressings (CDD). Methods: We examined patients who underwent Mohs or standard surgical excision with linear closure followed by HCD. The patients additionally had a history of excisional surgery with CDD in the past 5 years. A modified version of the validated Bluebelle Wound Healing Questionnaire was administered. Results: The survey response rate was 74.4% (64/86). Compared with CDD, HCD rated higher in comfort, convenience, scar appearance, and simplicity of wound care instructions (P < .0001). Nearly all patients (96.8%) preferred HCD over CDD. Limitations: Variability in time from prior dermatologic surgery may introduce recall bias. Prior surgeries involving CDD were sometimes performed by a different surgeon, which could introduce other confounding factors. Conclusions: A simplified wound care regimen involving HCD can potentially lead to increased comfort, convenience, simplicity, and a subjective improvement in scar appearance, though additional studies are needed.