Association of Time to Definitive Hemostasis With Mortality in Patients With Solid Organ Injuries.

Introduction The Golden Hour is a term used in the trauma setting to refer to the first 60 minutes after injury. Traditionally, definitive care within this period was believed to dramatically increase a patient's survival. Though the period of 60 minutes is unlikely to represent a point of distinct inflection in survival, the effect of time to definitive care on survival remains incompletely understood. This study aims to measure the association of time to definitive hemostasis with mortality in patients with solid organ injuries as well as the effect of survival bias and a form of selection bias known as indication by severity on the relationship between time to treatment and survival. Methodology This is a retrospective cohort study using data obtained from the American College of Surgeons National Trauma Data Bank (NTDB) from the years 2017 through 2019 selecting patients treated for blunt liver, spleen, or kidney injury who required angioembolization or surgical hemostasis within six hours. A Cox proportional hazards regression was used to analyze time to death. The association of probability of death with time was examined with a multivariate logistic regression initially treating the relationship as linear and subsequently transforming time to hemostasis with restricted cubic splines to model a non-linear association with the outcome. To model survival and indication by severity bias, we created a computer-generated data set and used LOESS regressions to display curves of the simulated data. Results The multivariate Cox proportional hazards analysis shows a coefficient of negative 0.004 for minutes to hemostasis with an adjusted hazard ratio of 0.9959 showing the adjusted hazard of death slightly diminishes with each increasing minute to hemostasis. The likelihood ratio chi-square difference between the model with time to hemostasis included as a linear term versus the model with the restricted cubic spline transformation is 97.46 (p<0.0001) showing the model with restricted cubic splines is a better fit for the data. The computer-generated data simulating treatment of solid organ injury with no programmed bias displays an almost linear association of mortality with increased treatment delay. When indications by severity bias and survival bias are introduced, the risk of death decreases with time to hemostasis as in the real-world data. Conclusion Decreasing mortality with increasing delay to hemostasis in trauma patients with solid organ injury is likely due to confounding due to indication by severity and survival bias. After taking these biases into account, the association of delayed hemostasis with better survival is not likely due to the benefit of delay but rather the delay sorts patients by severity of injury with those more likely to die being treated first. These biases are extremely difficult to eliminate which limits the ability to measure the true effect of delay with retrospective data. The findings may however be of value as a predictive model to anticipate the acuity of a patient after an interval of unavoidable delay such as with a long transfer time.

Elevated Cardiac Troponin Is Most Often Associated With Type 2 Myocardial Infarction in Trauma Patients.

Introduction Cardiac troponin (cTn) forms an essential part of the diagnostic criteria for myocardial infarction (MI). Type 1 MI is a primary coronary arterial event, whereas type 2 MI is due to coronary oxygen supply/demand mismatch, which is common in trauma patients. In addition, cTn may be elevated for many reasons other than MI. cTn elevations in trauma may not be specific for MI amenable to revascularization. The aim of this study is to determine which subset of trauma patients benefits from measuring cTn, and which patients with elevated cTn benefit from ischemic workup. Methods This is a retrospective cohort study. All patients on the trauma service of a level 1 trauma center with cTn elevated above the upper reference value of 0.032 ng/ml from July 2017 through December 2020 were selected. Baseline characteristics were recorded. The main outcomes were cardiology determination of the etiology of elevated cTn and patient survival. Logistic regression was used for multivariate analysis. Results One hundred forty-seven (147; 1.1%) of 13746 trauma patients had maximum cTn over the 99th percentile. Forty-one (27.5%) of the 147 had ischemic changes on electrocardiogram (ECG). Sixty-four (43.0%) had chest pain. In 81 (55.1%) cases, cTn was ordered without a clearly justified indication. One hundred thirty-seven patients (93.3%) received a cardiology consult. Two (1.5%) of 137 patients had a type 1 MI, which was diagnosed by ECG and clinical symptoms before cTn results were available. One hundred thirty-five patients were evaluated for cardiac ischemia based on elevated cTn. In 91 (66.4%) cases, the elevated cTn was attributed to a cardiac oxygen supply/demand mismatch. The etiology was cardiac contusion for 26 (19.0%), with the rest attributed to various other trauma-related causes. The cardiology consult changed management for 90 (65.7%) patients, mainly consisting of further evaluation by echocardiogram for 78 (57.0%) patients. Elevated cTn was a significant independent predictor of death with an adjusted odds ratio of 2.6 (p=0.002). Conclusion Isolated cTn values in trauma are most often due to type 2 MI resulting from trauma-related issues, such as tachycardia and anemia, which affect myocardial oxygen supply and demand. Changes in management generally consisted of further workup and interventions such as monitoring and pharmacologic treatment. Elevated cTn in this cohort never led to revascularization but was valuable to identify patients who required more intensive monitoring, longer-term follow-up, and supportive cardiac care. More selective ordering of cTn would improve specificity for patients requiring specialized cardiac care.

Fluid and Solute Intakes Show Minimal Association With Serum Sodium Levels in a Mixed ICU Population.

BACKGROUND:  Hyponatremia is common among hospital inpatients. It is generally due to excess free body water resulting from increased water intake and decreased water elimination due to underlying pathology and hormonal influence. However, supporting evidence is lacking for treating mild hyponatremia with fluid restriction. Our study examines the association between hyponatremia and fluid intake in acutely ill inpatients. We hypothesize that fluid intake is not closely associated with serum sodium (SNa). METHODS:  We conducted a retrospective study of hyponatremia using the Multiparameter Intelligent Monitoring in Intensive Care (MIMIC) III dataset, a public ICU registry. We analyzed fluid, sodium, and potassium intake with a mixed model linear regression with SNa as the outcome for hyponatremic and non-hyponatremic patients and cumulative total input from one to seven days. In addition, we compared a group of patients receiving less than one liter of fluid per day to a group receiving more than one liter. RESULTS:  The association of SNa with fluid intake was negative and statistically significant for most cumulative days of intake from one to seven for the total population and those with sporadic hyponatremia. For those with uniform hyponatremia, the negative association was significant for three and four days of cumulative input. The change in SNa was almost always less than 1 mmol/L of additional fluid intake across all groups. SNa for hyponatremic patients who received less than one liter of fluid per day were within one mmol/L of those who received more (p<0.001 for one, two, and seven cumulative intake days). CONCLUSIONS:  SNa is associated with a change of less than 1 mmol/L across a wide range of fluid and sodium intake in adult ICU patients. Patients who received less than one liter per day had SNa almost identical to those who received more. This suggests that SNa is not tightly coupled with fluid intake in the acutely ill population and that hormonal control of water elimination is the predominant mechanism. This might explain why the correction of hyponatremia by fluid restriction is often difficult.

Endpoints in Vital Signs as a Useful Tool for Measuring Successful Needle Decompression After Traumatic Tension Pneumothorax: An Analysis of the National Emergency Medicine Information System Database.

Background Needle decompression is a useful tool in the pre-hospital setting for treating tension pneumothorax. However the specific improvements in vital signs that determine a successful decompression are only reported in a few studies and Emergency Medical Services (EMS) self-reported assessments of improvement are more commonplace. We hypothesize that EMS reports may exaggerate improvement when compared to objective vital sign changes. Methodology This is a retrospective cohort study using the National Emergency Medicine Information System (NEMSIS) for the year 2020. Vital signs recorded as objective endpoints include systolic blood pressure (SBP), pulse (HR), respiratory rate (RR), and oxygen saturation (SpO2). Univariate analysis was performed using the t-test for continuous variables and the chi-square test for categorical variables. Results A total of 8,219 calls were included in the sample size analyzed. Most patients were white (2,911, 35.4%) and male (6,694, 81.4%). Abnormal vitals recorded as indications for needle decompression included SBP <100 mmHg, HR <60 or >100 beats/minute, RR <12 or >20 breaths/minute, and SpO2 <93%. Statistically significant improvements were seen in the number of abnormal vital signs after the procedure. The percentage of improvement was higher in the EMS self-reported assessment than in objective findings for oxygen saturation and SBP. Conclusions Our analysis shows objective improvement of hypoxia and hypotension after field needle decompression, supporting the efficacy of the procedure. The improvement based on vital sign change is modest and is less than that reported by EMS assessment of global improvement. This represents a target for quality improvement in EMS practice.

Hospital-Acquired Condition Rate of Admitting Facility Does Not Predict Mortality in Traumatically Injured Patients.

BACKGROUND: Hospital-acquired conditions (HACs) are increasingly scrutinized as markers of hospital quality and are subject to increasing regulatory and financial pressure. Despite this, there is little evidence that HACs are associated with poor outcomes in traumatically injured patients, or that lower HAC rates are a marker of a better quality of care. Our study compares mortality rates in hospitals with high versus low rates of HAC. Our hypothesis is that high HAC trauma centers have higher mortality. METHODS: The latest editions of the National Trauma Data Bank (NTDB) containing facility identification keys (2011 to 2015) were combined. The HACs targeted by the Centers for Medicare and Medicaid Services (CMS) Hospital-Acquired Condition Reduction Program (HACRP) were identified. Hospital-acquired conditions per 1000 patient-days were calculated for individual trauma centers, and these facilities were stratified into quartiles by HAC rate. Propensity score matching was used to match patients admitted to hospitals in the highest versus the lowest quartiles. RESULTS: Complete data was available for 3,510,818 patients; 58,296 (1.67%) developed HACs recorded in the NTDB. Good performing centers had a mean of 0.84 HACs per 1000 patient-days compared to 7.82 at poor-performing centers. After propensity matching, patients treated at good performing centers had higher mortality of 1.22% versus 1.02% at poor-performing centers (p<0.001). The facility characteristics most over-represented in the poor performing quartile were: University (45.19% vs 10.59%, p<0.001), American College of Surgeons (ACS) Level I Status (31.85% vs 2.24%, p<0.001), and bed size > 600 (28.15% vs 5.5%, p<0.001). CONCLUSION: Injured patients treated at poor-performing centers (high HAC) have reduced mortality relative to good performing centers (low HAC). Large academic centers were overwhelmingly represented in the poor-performing quartile. Hospital-acquired conditions may be markers of a non-modifiable underlying patient and facility characteristics rather than markers of poor hospital quality.

Increasing Rate of Pulmonary Embolism in Trauma Patients at a Level One Trauma Center: An Opportunity for Quality Improvement?

Introduction Pulmonary embolism (PE) is the most common cause of preventable hospital death in trauma patients, with 100,000 patients dying from PE annually. A steadily increasing PE rate was observed over seven years in the trauma population at a single level one trauma center. Our study seeks to analyze this trend by examining risk factors and searching for targets for improvement. We hypothesized that a change in one or more modifiable risk factors was associated with the increased PE rate.  Methods This retrospective cohort study considered trauma patients admitted to our trauma center between 2012 and 2018. The change in PE rate over time and correlation with various risk factors were examined using logistic regression. The study population was divided into two cohorts: early (2012-2015), and late (2016-2018). Data were collected from a prospectively maintained trauma database. More detailed information was obtained from individual patient charts for 533 patients worked up for PE. Risk factors were evaluated using both univariate and multivariate analysis. Results A total of 14,986 trauma patients were included in the study, of which 132 were diagnosed with PE. The PE rate was 1.11% in the late group compared to 0.67% in the early group (p=.004). We detected no association between the PE rate and preventive measures such as screening for and treating deep venous thrombosis (DVT), placing inferior vena cava (IVC) filters, and patterns of chemical DVT prophylaxis. We did not observe a distal migration of the anatomic distribution of PEs on CT pulmonary angiogram (CTPA). There were nonsignificant trends between PE rate and changes in population demographics and injury patterns, increased frequency of major surgery, and increased tranexamic acid (TXA) use. Of known risk factors for PE, units of packed red blood cells (PRBC) (p=0.041), units of fresh frozen plasma (FFP) (p=.037), and the number of patients receiving transfusion (p=0.043) were all significantly greater in the later period. Conclusion Change in hemostatic resuscitation practices (use of balanced ratios of blood products) is most likely to have contributed to the increased PE rate at our institution. However, PE in trauma is multifactorial, and the increased rate cannot be attributed to any single factor. We did not observe a lapse in preventive measures commonly considered indices of quality of care. Caution is advised against overreliance on PE rate as a measure of quality.

Analysis of Predictors of Myocardial Infarction in Trauma With Development of a Trauma Cardiac Risk Index.

STUDY OBJECTIVE: Trauma has historically been considered a disorder of the young and healthy, with a low risk of cardiac ischemia; hence most research on myocardial infarction in trauma has focused on direct cardiac damage from blunt chest trauma. However, the age and comorbidity of trauma patients are increasing, making the trauma population more vulnerable to myocardial infarction (MI). Cardiac risk assessment has emphasized morbidity and mortality in an elective surgical setting, but it is also important in acute trauma. Our study analyzes the risk factors for MI in a trauma population to create a scoring system to predict the risk of MI. DESIGN:  Retrospective cohort analysis of a national trauma registry over a five-year period. Potential predictors of MI in trauma patients were identified and tested with univariate and multivariate statistics. A numerical score was created to predict the risk of MI based on these criteria. SETTING: The National Trauma Data Bank (NTDB) is a large registry of selected trauma centers in the United States. Data include demographic, injury, treatment, and outcome variables pertaining to the index admission of each patient. The institutions range from community hospitals through level 1 trauma centers. The time period is the entire inpatient hospital admission from arrival from the field, through the emergency department, ICU, and floor up to discharge. PATIENTS: 3,437,959 trauma patients aged 18 years and older from various US trauma centers. 62.8% were male. The median age is 50 years with a standard deviation of 21.25. The median Injury Severity Score is 9 with a standard deviation of 9.04. MEASUREMENTS: Demographic, traumatic, and comorbidity variables were collected from the NTDB. The primary outcome was MI during the initial trauma admission. Multivariate analysis was performed with logistic regression. MAIN RESULTS: Over 8010 (0.23%) suffered an MI. The strongest risk factors for MI were a history of MI with an adjusted odds ratio (OR) of 7.0, and angina with an OR of 3.4. A procedure under general anesthesia (GA) conferred an OR of 2.3. Minor risk factors included torso injury and 10-year age interval over 50, both with an OR of 1.7, a 20-point interval of the Injury Severity Score (ISS) with OR 1.6, male gender with OR of 1.5, and various chronic disease comorbidities with OR ranging from 1.4 to 1.9. A Trauma Cardiac Risk Index (TCRI) was derived from these risk factors. The model showed good discrimination with a C statistic of 0.85. CONCLUSIONS: Overall the trauma population has a low risk of MI. However, the risk is much higher for older patients with chronic comorbidity. The TCRI can be used to assess cardiac risk in trauma patients to help direct monitoring, testing, and risk reduction measures to those at the highest risk.

The Effect of Illegal Drug Screening Results and Chronic Drug Use on Perioperative Complications in Trauma.

CONTEXT: Illegal drug use and need for surgery are common in trauma. This allows examination of the effects of perioperative drug use. AIM: The aim was to study the effects of illegal drug use on perioperative complications in trauma. SETTING AND DESIGN: Propensity-matched analysis of perioperative complications between drug screen-positive (DSP) and drug screen-negative (DSN) patients from the National Trauma Data Bank (NTDB). METHODS: The NTDB reports drug screening as a composite. We compared complications for DSP, DSN, and specific chronic drug disorders. Time to first procedure was analyzed to determine whether delay to surgery was associated with reduced complications. STATISTICS: Logistic regression with 11 predictor variables was used to calculate propensity scores. Categorical and continuous variables were compared using Chi-square and Student's t-test, respectively. RESULTS: 752,343 patients (21.9%) were tested for illegal drugs. DSP was protective for mortality-relative risk (RR) 0.84 (P < 0.001) and arrhythmia RR 0.87 (P = 0.02). All complications (AC) were higher for DSP with a RR of 1.08 (P < 0.001). Cocaine, cannabis, and opioids were associated with reduced mortality. Cocaine was associated with increased myocardial infarction (MI). All four chronic drug disorders were associated with markedly higher arrhythmia. All except cannabis were associated with higher AC. Mortality was significantly lower for DSP for every time interval until first procedure. Continuous-time until procedure was associated with increased MI and arrhythmia. CONCLUSIONS: DSP was protective of mortality and cardiac complications. Drug disorders were protective for mortality but increased arrhythmia and AC. Delay until the surgery does not diminish cardiac or overall risk.

Efficacy and Safety of Tranexamic Acid in Prehospital Traumatic Hemorrhagic Shock: Outcomes of the Cal-PAT Study.

INTRODUCTION: The California Prehospital Antifibrinolytic Therapy (Cal-PAT) study seeks to assess the safety and impact on patient mortality of tranexamic acid (TXA) administration in cases of trauma-induced hemorrhagic shock. The current study further aimed to assess the feasibility of prehospital TXA administration by paramedics within the framework of North American emergency medicine standards and protocols. METHODS: This is an ongoing multi-centered, prospective, observational cohort study with a retrospective chart-review comparison. Trauma patients identified in the prehospital setting with signs of hemorrhagic shock by first responders were administered one gram of TXA followed by an optional second one-gram dose upon arrival to the hospital, if the patient still met inclusion criteria. Patients administered TXA make up the prehospital intervention group. Control group patients met the same inclusion criteria as TXA candidates and were matched with the prehospital intervention patients based on mechanism of injury, injury severity score, and age. The primary outcomes were mortality, measured at 24 hours, 48 hours, and 28 days. Secondary outcomes measured included the total blood products transfused and any known adverse events associated with TXA administration. RESULTS: We included 128 patients in the prehospital intervention group and 125 in the control group. Although not statistically significant, the prehospital intervention group trended toward a lower 24-hour mortality rate (3.9% vs 7.2% for intervention and control, respectively, p=0.25), 48-hour mortality rate (6.3% vs 7.2% for intervention and control, respectively, p=0.76), and 28-day mortality rate (6.3% vs 10.4% for intervention and control, respectively, p=0.23). There was no significant difference observed in known adverse events associated with TXA administration in the prehospital intervention group and control group. A reduction in total blood product usage was observed following the administration of TXA (control: 6.95 units; intervention: 4.09 units; p=0.01). CONCLUSION: Preliminary evidence from the Cal-PAT study suggests that TXA administration may be safe in the prehospital setting with no significant change in adverse events observed and an associated decreased use of blood products in cases of trauma-induced hemorrhagic shock. Given the current sample size, a statistically significant decrease in mortality was not observed. Additionally, this study demonstrates that it may be feasible for paramedics to identify and safely administer TXA in the prehospital setting.