Neal Handly

Evidence of Hormonal Basis for Improved Survival Among Females With Trauma-associated Shock: An Analysis of the National Trauma Data Bank

BACKGROUND Basic science research suggests that sex hormones affect survival after traumatic shock. This study sought to determine the independent effect of gender on mortality among trauma patients in different hormone-related age groups. METHODS Review of severely injured trauma patients with shock included in the National Trauma Databank. Patients were stratified into three groups on the basis of likely hormonal status: prehormonal (age, 0-12 years), hormonal (age,13-64 years), and posthormonal (age, ≥ 65 years). Multiple logistic regression was used to analyze the independent effect of gender on mortality in each group, adjusting for anatomic and physiologic injury severity. RESULTS A total of 48,394 patients met our inclusion criteria (Injury Severity Score ≥ 16 and systolic blood pressure <90 mm Hg). Crude mortality was higher (p < 0.05) for males in all categories: prehormonal = 29% for males (n = 3,553) versus 24% for females (n = 1,831); hormonal = 34% for males (n = 26,778) versus 30% for females (n = 8,677) and posthormonal = 36% for males (n = 4,280) versus 31% for females (n = 3,275). After adjusting for covariates, women in the hormonally active group had a 14% decreased odds of death (0.86 [95% CI, 0.76-0.93]) compared with men. Females did not exhibit this survival advantage in the prehormonal (odds of death = 0.92 [0.74-1.14]) or posthormonal (odds of death = 0.90 [0.76-1.05]) groups. CONCLUSIONS Females aged between 13 and 64 years exhibit significantly lower mortality than males after trauma-associated shock. This outcome difference is lost at the extremes of age (preadolescent children and individuals aged ≥ 65 years) where the effects of sex hormones are absent or diminished. These findings suggest that hormonal differences play a role in the gender-based outcome disparities after traumatic shock.

Clinical Evaluation of a Portable Near-Infrared Device for Detection of Traumatic Intracranial Hematomas

The purpose of this multicenter observational clinical study was to evaluate the performance of a near-infrared (NIR)-based, non-invasive, portable device to screen for traumatic intracranial hematomas. Five trauma centers collected data using the portable NIR device at the time a computed tomography (CT) scan was performed to evaluate a suspected traumatic brain injury (TBI). The CT scans were read by an independent neuroradiologist who was blinded to the NIR measurements. Of 431 patients enrolled, 365 patients were included in the per-protocol population analyzed. Of the 365 patients, 96 were determined by CT scan to have intracranial hemorrhages of various sizes, depths, and anatomical locations. The NIR device demonstrated sensitivity of 88% (95% confidence interval [CI] 74.9,95.0%), and specificity of 90.7% (95% CI 86.4,93.7%), in detecting the 50 intracranial hematomas that were large enough to be clinically important (larger than 3.5 mL in volume), and that were less than 2.5 cm from the surface of the brain. For all 96 cases with intracranial hemorrhage, regardless of size and type of hemorrhage, the sensitivity was 68.7% (CI 58.3,77.6%), and specificity was 90.7% (CI 86.4,93.7%). These results confirm the results of previous studies that indicate that a NIR-based portable device can reliably screen for intracranial hematomas that are superficial and of a size likely to be of clinical importance. The NIR device cannot replace CT scanning in the diagnosis of TBI, but the device might be useful to supplement clinical information used to triage TBI patients, and in situations in which CT scanning is not readily available.

The occurrence of potential patient safety events among trauma patients: are they random?

Objective:The Patient Safety Indicators (PSIs) from the Agency for Healthcare Research and Quality are validated measures of quality of care. The pattern of PSIs among adult trauma patients is unknown. Hypothesis:The occurrence of PSI events should be random and have no identifiable pattern across age, gender, and racial groups in trauma, because trauma services are designed to be an equal-access system. Design:Retrospective analysis of a nationally representative dataset. Setting:Nationwide Inpatient Sample (representative 20% sample from 37 states) for 5 years (2000 through 2004). Patients:Patients aged ≥18 admitted primarily for trauma. Outcomes:Occurrence of at least one of the applicable PSIs on multiple logistic regression analysis, with confirmation by sensitivity analysis. Results:A total of 1.35 million trauma patients were identified, with 19,338 patients (1.43%) experiencing at least one of the applicable PSIs. On multivariate analysis, controlling for injury severity and disease comorbidity, the adjusted odds ratios (ORs) for occurrence of at least 1 applicable PSI were noted to increase for patients who are 1) above age 35, 2) male gender (OR 1.25, 95% CI 1.19–1.31), and 3) black (OR 1.20 vs. whites, 95% CI 1.10-1.30) but not for any other racial groups. These results did not change significantly on sensitivity analysis. Conclusions:Patients who are above age 35, male gender, and black are associated with increased likelihood of experiencing a patient safety event in trauma care. When all else is equal, black patients are approximately 20% more likely than any other racial groups to experience a patient safety event, even after controlling for injury severity and disease comorbidity. These findings can help institutions prioritize chart review-based investigations to determine potential targets of systems improvement.

Improving Patient Safety With Ultrasonography Guidance During Internal Jugular Central Venous Catheter Placement by Novice Practitioners

Introduction: This study compared ultrasonography-guided (USG) placement with anatomic placement during internal jugular (IJ) central venous catheter (CVC) insertion by novice practitioners using a simulation model. Methods: A prospective, randomized, crossover study of 28 fourth year medical students was conducted with institutional review board approval. Participants viewed an instructional material before participation, and supervision was standardized. Participants were randomly assigned to either USG or traditional landmark method first, and each group served as its own crossover comparison. Paired t tests and &khgr;2 analysis were performed on matched-pair data. Results: Fifty-four percent of participants had at least one arterial stick without USG compared with 0% when using USG. Significant differences were shown in the USG versus no-USG groups in number of needle advances until successful cannulation of the vein: mean with USG = 1.5 advances (95% CI, 1.0–1.9), mean without USG = 10.4 advances (95% CI, 7.8–13), P < 0.001; time to successful cannulation: mean with USG = 58 seconds (95% CI, 48–72 seconds), mean without USG = 338 seconds (95% CI, 286–390 seconds), P < 0.001; and success rates: 100% with USG and 42.8% without USG (95% CI, 24.5%–61.1%). The number needed to treat to avoid an arterial stick by using USG during IJ insertion by novice practitioners is ∼2. Conclusions: The USG during IJ CVC placement by novice practitioners is essential to improve patient safety. If these data are extrapolated to impact on patient care, an arterial stick may be avoided in one of every two IJ CVCs placed by novice practitioners. The USG technology should be made available to novice practitioners needing to place CVCs.

Subclavian central venous catheters and ultrasound guidance: policy vs practice.

Purpose Policy statements recommend the use of ultrasound guidance (USG) to improve patient safety during placement of central venous catheters (CVCs). Studies have conclusively demonstrated greater success rates and fewer complications with the use of USG in catheter placement using the internal jugular vein approach. Data supporting the use of USG for the subclavian vein (SCV) approach, however, have been less conclusive, and USG for SCV cannulation is rarely used in clinical practice. We compared USG placement versus anatomic placement during subclavian insertion of a CVC. Methods A prospective randomized study was performed in March 2010 using a simulation model. Results Ultrasound guidance did not provide a statistically significant benefit for successful cannulation of the SCV (93.3% with USG and 100% without; P=0.15 or 2) or for rate of inadvertent arterial puncture (3.3% with USG and 0% without; P=0.31). Conclusions The use of USG to access the SCV utilizing a task trainer did not improve time to cannulation or success rates. Further study is required to delineate why USG for SCV cannulation has not been widely adopted in clinical practice.

Hospital Admission Prediction Using Pre-hospital Variables

With the rapid outstripping of healthcare resourcesby the demands on hospital care, it is important to findmore effective and efficient ways for managing care.This research is aimed at developing new admissionprediction models using various pre-hospital variablesto help hospital estimate the patients to be admitted.We developed a framework of hospital admissionprediction and proposed two novel approaches tocapture semantics of chief complaints to enhanceprediction. Our experiments on a hospital datasetdemonstrated that our proposed models outperformedseveral benchmark methods.

Ejection fraction as related to basic components in the left and right ventricular volume domains

BACKGROUND Ejection fraction (EF) is commonly applied as a clinically relevant metric to assess ventricular function. The numerical value of EF depends on the interplay between end-systolic volume (ESV) and end-diastolic volume (EDV). Remarkably, the relative impact of the two constitutive components on EF received little attention. METHODS Three patient groups not using beta-blockers were analyzed for a robust investigation into the relative contribution of ESV and EDV when assessing EF: cardiac patients (N=155) with left ventricular (LV) data obtained by biplane ventriculography, near-normals (N=276) by gated SPECT investigation, and an MRI-based post Fallot repair study including right ventricular (RV) data (N=124), besides LV. We compared various routes to evaluate EF via linear and several types of nonlinear regression with ESV as independent variable. Advanced statistics was applied to evaluate sex-specific differences. RESULTS In all cases ESV emerges as the dominant component of EF, with less (P<0.0001) impact of EDV. The relationship for EF versus ESV is nonlinear (P<0.0001), and similar for both sexes. A linear approach may be inadequate and generate erroneous statistical outcomes when comparing subgroups of patients. CONCLUSIONS Values for EF primarily depend on ESV, both for LV and RV. This relationship is essentially nonlinear, and similar for both sexes. A logarithmic approximation is convenient and often acceptable. However, application of linear regression for EF vs ESV may lead to incorrect conclusions, particularly when comparing males and females.

Evaluation of a hospital admission prediction model adding coded chief complaint data using neural network methodology

Objective Our objective was to apply neural network methodology to determine whether adding coded chief complaint (CCC) data to triage information would result in an improved hospital admission prediction model than one without CCC data. Participants and methods We carried out a retrospective derivation and validation cohort study of all adult emergency department visits to a single center. We downloaded triage, chief complaint, and admission/discharge data on each included visit. Using a CCC algorithm and the Levenberg–Marquardt back-propagation learning method, we derived hospital admission prediction models without and with CCC data and applied these to the validation cohort, reporting the prediction models’ characteristics. Results A total of 74 056 emergency department visits were included in the derivation cohort, 85 144 in the validation cohort with 213 CCC categories. The sensitivity/specificity of the derivation cohort models without and with CCC data were 64.0% [95% confidence interval (CI): 63.7–64.3], 87.7% (95% CI: 87.4–88.0), 59.8% (95% CI: 59.5–60.3%), and 91.7% (95% CI: 91.4–92.0) respectively. The sensitivity/specificity of the derived models without and with CCC data applied to the validation cohort were 60.7% (95% CI: 60.4–61.0), 87.7% (95% CI: 87.4–88.0), 59.8% (95% CI: 59.5–60.3), and 90.6% (95% CI: 90.3–90.9) respectively. The area under the curve in the validation cohort for the derived models without and with CCC data were 0.840 (95% CI: 0.838–0.842) and 0.860 (95% CI: 0.858–0.862). Net reclassification index (0.156; 95% CI: 0.148–0.163) and integrated discrimination improvement (0.060; 95% CI: 0.058–0.061) in the CCC model were significant. Conclusion Neural net methodology application resulted in the derivation and validation of a modestly stronger hospital admission prediction model after the addition of CCC data.

Left ventricular volume analysis as a basic tool to describe cardiac function

The heart is often regarded as a compression pump. Therefore, determination of pressure and volume is essential for cardiac function analysis. Traditionally, ventricular performance was described in terms of the Starling curve, i.e., output related to input. This view is based on two variables (namely, stroke volume and end-diastolic volume), often studied in the isolated (i.e., denervated) heart, and has dominated the interpretation of cardiac mechanics over the last century. The ratio of the prevailing coordinates within that paradigm is termed ejection fraction (EF), which is the popular metric routinely used in the clinic. Here we present an insightful alternative approach while describing volume regulation by relating end-systolic volume (ESV) to end-diastolic volume. This route obviates the undesired use of metrics derived from differences or ratios, as employed in previous models. We illustrate basic principles concerning ventricular volume regulation by data obtained from intact animal experiments and collected in healthy humans. Special attention is given to sex-specific differences. The method can be applied to the dynamics of a single heart and to an ensemble of individuals. Group analysis allows for stratification regarding sex, age, medication, and additional clinically relevant covariates. A straightforward procedure derives the relationship between EF and ESV and describes myocardial oxygen consumption in terms of ESV. This representation enhances insight and reduces the impact of the metric EF, in favor of the end-systolic elastance concept advanced 4 decades ago.

Semantic-enhanced models to support timely admission prediction at emergency departments

With the rapid outstripping of limited health care resources by the demands on hospital care, it is of critical importance to find more effective and efficient methods of managing care. Our research addresses the problem of emergency department (ED) crowding by building classification models using various types of pre-admission information to help predict the hospital admission of individual patients. We have developed a framework of hospital admission prediction and proposed two novel approaches that capture semantic information in chief complaints to enhance prediction. Our experiments on an ED data set demonstrate that our proposed models outperformed several benchmark methods for admission prediction. These models can potentially be used as decision support tools at hospitals to improve ED throughput rate and enhance patient care.