Admission lactate level and the APACHE II score are the most useful predictors of prognosis following torso trauma

Measuring the Level of Agreement for Lactate Measurements in Hispaniolan Amazon Parrots (Amazona ventralis) Among 2 Point-of-Care Analyzers and a Benchtop Analyzer

Lactate is an important biochemistry analyte used in human and veterinary medicine to assess tissue perfusion and can be used as a prognostic indicator for certain disease conditions. Whereas lactate is commonly measured using "patient-side" handheld meters, these meters have not been validated for companion avian species. The purpose of this study was to measure the level of agreement between 2 commercially available point-of-care lactate meters and a laboratory benchtop blood analyzer in Hispaniolan Amazon parrots (Amazona ventralis). Blood samples were collected from 20 adult parrots at Louisiana State University by drawing 1.5 mL of blood from the right jugular vein. One drop of whole blood was used for the Lactate Plus analyzer and the remainder of the sample transferred into a lithium heparin microtainer. From the blood in the microtainer, 0.2 mL whole blood was analyzed using the epoc Blood Analysis System, and the remaining sample was centrifuged to obtain plasma that was immediately frozen at -80°C (-112°F) and submitted to the Texas A&M University Clinical Pathology Laboratory for analysis on the VITROS 4500 benchtop analyzer. Bland-Altman agreement plots and Passing-Bablok regression were used to measure the level of agreement between the methods. There was poor agreement between all 3 methods with mean percentage differences in lactate concentrations ≥22% (epoc and Lactate Plus: 33.6% [95% CI: 27-40]; epoc and VITROS 4500: 55% [95% CI:52-58]; VITROS 4500 and Lactate Plus: 22% [95% CI:16-28]). Based on these results, the point-of-care meters tested in this study are not interchangeable, and separate reference intervals were calculated for each method. Blood lactate concentrations may have more utility in tracing lactate trends over time in an individual rather than being able to utilize this information at 1 time point for disease diagnosis and prognosis.

Impact of Serum Lactate as an Early Serum Biomarker for Cardiopulmonary Parameters within the First 24 Hours of Intensive Care Unit Treatment in Patients with Isolated Traumatic Brain Injury

OBJECTIVE

Cardiopulmonary (CP) complications are well-known phenomena in patients with isolated traumatic brain injury (iTBI) that can lead to tissue hypoperfusion and hypoxia. Serum lactate level is a well-known biomarker, indicating these systemic dysregulations in various diseases, but this has not been investigated in iTBI patients so far. The current study evaluates the association between serum lactate levels upon admission and CP parameters within the first 24 h of intensive care unit (ICU) treatment in iTBI patients.

PATIENTS AND METHODS

182 patients with iTBI who were admitted to our neurosurgical ICU between December 2014 and December 2016 were retrospectively evaluated. Serum lactate levels on admission, demographic, medical, and radiological data upon admission, as well as several CP parameters within the first 24 h of ICU treatment, were analyzed, as well as the functional outcome at discharge. The total study population was dichotomized into patients with an elevated serum lactate level (lactate-positive) and patients with a low serum lactate level (lactate-negative) upon admission.

RESULTS

69 patients (37.9%) had an elevated serum lactate level upon admission, which was significantly associated with a lower Glasgow Coma Scale score (p = 0.04), a higher head AIS score (p = 0.03), and a higher Acute Physiology and Chronic Health Evaluation II score (p = 0.01) upon admission, as well as a higher modified Rankin Scale score (p = 0.002) and a lower Glasgow Outcome Scale score (p < 0.0001) at discharge. Furthermore, the lactate-positive group required a significantly higher norepinephrine application rate (NAR; p = 0.04) and a higher fraction of inspired oxygen (FiO2; p = 0.04) to maintain the defined CP parameters within the first 24 h.

CONCLUSION

ICU-admitted iTBI patients with elevated serum lactate levels upon admission required higher CP support within the first 24 h of ICU treatment after iTBI. Serum lactate may be a helpful biomarker for improving ICU treatment in the early stages.

Acute Kidney Injury: Iterative Development of an Audit Tool for Trauma Patients

BACKGROUND

Acute kidney injury is a low-volume, high-risk complication in trauma patients and is associated with prolonged hospital length of stay and increased mortality. Yet, no audit tools exist to evaluate acute kidney injury in trauma patients.

OBJECTIVE

This study aimed to describe the iterative development of an audit tool to evaluate acute kidney injury following trauma.

METHODS

Our performance improvement nurses developed an audit tool to evaluate acute kidney injury in trauma patients using an iterative, multiphase process conducted from 2017 to 2021, which included a review of our Trauma Quality Improvement Program data, trauma registry data, literature review, multidisciplinary consensus approach, retrospective and concurrent review, and continuous audit and feedback for piloted and finalized versions of the tool.

RESULTS

The final acute kidney injury audit tool can be completed within 30 min using data obtained from the electronic medical record and consists of six sections, including identification criteria, source potential causes, source treatment, acute kidney injury treatment, dialysis indications, and outcome status.

CONCLUSION

The iterative development and testing of an acute kidney injury audit tool improved the uniform data collection, documentation, audit, and feedback of best practices to positively impact patient outcomes.

Rapid Measurement of Lactate in the Exhaled Breath Condensate: Biosensor Optimization and In-Human Proof of Concept

Lactate concentration is of increasing interest as a diagnostic for sepsis, septic shock, and trauma. Compared with the traditional blood sample media, the exhaled breath condensate (EBC) has the advantages of non-invasiveness and higher user acceptance. An amperometric biosensor was developed and its application in EBC lactate detection was investigated in this paper. The sensor was modified with PEDOT:PSS-PB, and two different lactate oxidases (LODs). A rotating disk electrode and Koutecky-Levich analysis were applied for the kinetics analysis and gel optimization. The optimized gel formulation was then tested on disposable screen-printed sensors. The disposable sensors exhibited good performance and presented a high stability for both LOD modifications. Finally, human EBC analysis was conducted from a healthy subject at rest and after 30 min of intense aerobic cycling exercise. The sensor coulometric measurements showed good agreement with fluorometric and triple quadrupole liquid chromatography mass spectrometry reference methods. The EBC lactate concentration increased from 22.5 μM (at rest) to 28.0 μM (after 30 min of cycling) and dropped back to 5.3 μM after 60 min of rest.

Serum Lactate as Serum Biomarker for Cardiopulmonary Parameters within the First 24 Hours after a Spontaneous Intracerebral Hemorrhage

Objective: Cardiopulmonary (CP) complications are well known in patients with an intracerebral hemorrhage (ICH) and could be associated with a higher serum lactate level. The present study aimed to assess the associations between the initial serum lactate level and the CP parameters within the first 24 h of intensive care unit (ICU) treatment in neurosurgical ICH patients. Patients and Methods: A total of 354 patients admitted to the ICU between 01/2009 and 12/2017 with a diagnosis of an ICH were retrospectively analyzed. Blood samples were taken upon admission, and each patient’s demographic, medical, and radiological data upon admission, as well as several CP parameters, were recorded within the first 24 h of ICU treatment. Results: A higher serum lactate level was associated with a lower GCS score (p < 0.0001), as well as a higher Acute Physiology and Chronic Health Evaluation II score (p = 0.002) upon admission. Additionally, patients with initially higher serum lactate levels had a significantly higher need for a norepinephrine application (p = 0.004) and inspiratory oxygen fraction (p = 0.03) within the first 24 h. Conclusion: Neurosurgical ICH patients with higher serum lactate levels upon admission require more CP support within the first 24 h of ICU treatment.

Characteristics and Survival of Patients with Acute Traumatic Spinal Cord Injury Above T6 with Prolonged Intensive Care Unit Stays

OBJECTIVE

To characterize patients with acute traumatic spinal cord injury (ATSCI) above T6 who were admitted to the intensive care unit (ICU) for ≥30 days and their 1-year mortality compared with patients admitted for <30 days.

METHODS

A retrospective observational study was performed on 211 patients with an acute traumatic spinal cord injury above T6 who were admitted to an ICU between 1998 and 2017. Multivariate logistic regression analysis was performed to determine the relationship between an ICU stay ≥30 days and mortality after ICU discharge.

RESULTS

Of patients, 29.4% were admitted to the ICU for ≥30 days, accounting for 53.4% of total days of ICU stays generated by all patients. An ICU stay ≥30 days was not identified as an independent risk factor for mortality (1-year survival: 88.5% vs. 88.1%; adjusted hazard ratio [HR] 0.80, P = 0.699). Variables identified as predictors of 1-year post-ICU discharge mortality were severity at admission according to the Acute Physiology and Chronic Health Evaluation II score (HR 1.18) and the American Spinal Injury Association Impairment Scale motor score (HR 0.97). Among patients who required invasive mechanical ventilation, a longer duration of the respiratory support was associated with increased mortality (HR 1.01).

CONCLUSIONS

Three out of 10 patients with acute traumatic spinal cord injury above T6 require prolonged stays in the ICU. Variables found to be associated with 1-year post-ICU discharge mortality in these patients were American Spinal Injury Association Impairment Scale motor score, severity, and greater duration of invasive mechanical ventilation, but not an ICU stay ≥30 days.

Is massive hemothorax still an absolute indication for operation in blunt trauma?

BACKGROUND

Surgery is usually suggested to treat massive haemothorax (MHT). The MHT criteria are based on penetrating trauma observations in military scenarios; the need for surgery in blunt trauma patients remains questionable. This study aimed to determine the characteristics of blunt trauma patients with MHT who required surgery.

METHODS

Patients who presented to the emergency department (ED) with traumatic haemothorax or pneumothorax, heart and lung injuries, and thoracic blood vessel injuries from Jan 1, 2014, to Dec 31, 2018, were reviewed. The inclusion criterion was a chest tube drainage amount that met the MHT criteria. Therapeutic operations were defined as those involving surgical haemostasis; otherwise, operations were considered non-therapeutic. The non-therapeutic operation group included the patients who received nonoperative management. The characteristics of the therapeutic and non-therapeutic operation groups were compared.

RESULTS

Forty-four patients were enroled in the study. Six patients received conservative treatment and were discharged uneventfully. Eleven patients underwent non-therapeutic operations. The patients with surgical bleeding had a high pulse rate (125.0 (111.0, 135.0) vs. 116.0 (84.0, 121.0) bpm, p = 0.013); low systolic blood pressure (SBP) after resuscitation (106.0 (84.0, 127.0) vs. 121.0 (116.0, 134.0) mmHg, p = 0.040); low pH (7.2 (7.2, 7.3) vs. 7.4 (7.3, 7.4), p = 0.002); and low bicarbonate (17.8 (14.6, 21.5) vs. 21.4 (17.0, 21.5) mEq/L, p = 0.038), low base excess (-9.1 (-13.4, -4.5) vs. -3.8 (-10.1, -0.7), p = 0.028), and high lactate (5.7 (3.3, 7.8) vs. 1.8 (1.7, 2.8) mmol/L, p = 0.002) levels.

CONCLUSION

Conservative treatment could be performed selectively in patients with MHT. Lactate could be a predictor of the need for surgical intervention in blunt trauma patients with MHT.

The malnutrition in polytrauma patients (MaPP) study: Research protocol

BACKGROUND

Polytrauma patients are at risk of considerable harm from malnutrition due to the metabolic response to trauma. However, there is little knowledge of (the risk of) malnutrition and its consequences in these patients. Recognition of sub-optimally nourished polytrauma patients and their nutritional needs is crucial to prevent complications and optimize their clinical outcomes.

AIM

The primary objective is to investigate whether polytrauma patients admitted to the Intensive Care Unit (ICU) who have or develop malnutrition have a higher complication rate than patients who are and remain well nourished. Secondary objectives are to determine the prevalence of pre-existent and in-hospital acquired malnutrition in these patients, to assess the association between malnutrition and long-term outcomes, and to determine the association between serum biomarkers (albumin and pre-albumin) and malnutrition.

METHODS

This international observational prospective cohort study will be performed at three Level-1 trauma centers in the United States and two Level-1 centers in the Netherlands. Adult polytrauma patients (Injury Severity Score ≥16) admitted to the ICU of one of the participating centers directly from the Emergency Department are eligible for inclusion. Nutritional status and risk of malnutrition will be assessed using the Subjective Global Assessment (SGA) scale and Nutritional Risk in Critically Ill (NUTRIC) score, respectively. Nutritional intake, biomarkers and complications will be collected daily. Patients will be followed up to one year after discharge for long-term outcomes.

CONCLUSIONS

This international prospective cohort study aims to gain more insight into the effect and consequences of malnutrition in polytrauma patients admitted to the ICU.

Comparisons of Traditional Metabolic Markers and Compensatory Reserve as Early Predictors of Tolerance to Central Hypovolemia in Humans

Circulatory shock remains a leading cause of death in both military and civilian trauma. Early, accurate and reliable prediction of decompensation is necessary for the most efficient interventions and clinical outcomes. Individual tolerance to reduced central blood volume can serve as a model to assess the sensitivity and specificity of vital sign measurements. The compensatory reserve (CRM) is the measurement of this capacity. Measurements of muscle oxygen saturation (SmO2), blood lactate, and end tidal CO2 (EtCO2) have recently gained attention as prognostic tools for early assessment of the status of patients with progressive hemorrhage, but lack the ability to adequately differentiate individual tolerance to hypovolemia. We hypothesized that the CRM would better predict hemodynamic decompensation and provide greater specificity and sensitivity than metabolic measures. To test this hypothesis, we employed lower body negative pressure on healthy human subjects until symptoms of presyncope were evident. Receiver operating characteristic area under the curve (ROC AUC), sensitivity, and specificity were used to evaluate the ability of CRM, partial pressure of oxygen (pO2), partial pressure of carbon dioxide (pCO2), SmO2, lactate, EtCO2, potential of hydrogen (pH), base excess and hematocrit (Hct) to predict hemodynamic decompensation. The ROC AUC for CRM (0.94) had a superior ability to predict decompensation compared with pO2 (0.85), pCO2 (0.62), SmO2 (0.72), lactate (0.57), EtCO2 (0.74), pH (0.55), base excess (0.59), and Hct (0.67). Similarly, CRM also exhibited the greatest sensitivity and specificity. These findings support the notion that CRM provides superior detection of hemodynamic compensation compared with commonly used clinical metabolic measures.

Agreement between arterial and venous blood gases in trauma resuscitation in emergency department (AGREE)

INTRODUCTION

Arterial blood gas (ABG) sampling is routinely performed in major trauma patients to assess the severity of hemorrhagic shock. Compared to venous blood gas (VBG), ABG is an additional procedure with risks of hematoma and pain. We aim to determine if pH, base deficit (BD), and lactate from VBG and ABG in trauma patients are clinically equivalent. If proven, the need for ABG and its associated risks can be eliminated.

METHODS

This prospective observational study was conducted in the Emergency Department of National University Hospital, Singapore, between February and October 2016. We correlated paired ABG and VBG results in adult trauma patients. VBG and ABG were obtained within 10 min and processed within 5 min using a point-of-care blood gas analyzer. Bland-Altman plot analysis was used to evaluate the agreement between peripheral VBG and ABG in terms of pH, base deficit and lactate.

RESULTS

There were 102 patients included, with a median age of 34 (interquartile range 28-46) years and male predominance (90.2%). Majority of patients sustained blunt trauma (96.1%), and had injuries of Tier 1 and Tier 2 severity (60/102, 58.8%). Bland-Altman plot analyses demonstrated that only 72.6% of venous pH and 76.5% of venous BD lie within the pre-defined clinically acceptable limits of agreement, whereas 96.0% of venous lactate was within these limits.

CONCLUSION

Venous and arterial pH and BD are not within clinically acceptable limits of agreement, and ABG should be obtained for accurate acid-base status. However, venous lactate may be an acceptable substitute for arterial lactate.

Prognostic Value of Blood Lactate and Base Deficit in Refractory Cardiac Arrest Cases Undergoing Extracorporeal Life Support

Objective

Cardiac arrest (CA) resuscitation is associated with an 'ischaemia-reperfusion' syndrome characterised by lactic acidosis as assessed by lactate and base deficit (BD). Both biomarkers are usually measured in patients suffering from refractory CA (RCA) subjected to extracorporeal life support (ECLS) to evaluate tissue reperfusion. However, their prognostic value has never been compared. The aim of the present study was to compare the prognostic value of both biomarkers measured at 0 and 3 h after the initiation of ECLS in patients with RCA on mortality.

Methods

Patients who were admitted to the intensive care unit with RCA were consecutively included in the study.

Results

Sixty-six patients were included. Lactate correlated with BD (R2=0.44, p<0.001). An area under the curve of 0.72 (95% confidence interval (CI) 0.59-0.84) was found for lactate and of 0.60 (95% CI 0.46-0.73) for BD. Using multivariable logistic regression, lactate (odds ratio (OR) 1.22, 95% CI 1.03-1.48) remained associated with mortality on day 28, but not BD (OR 0.99, 95% CI 0.86-1.14).

Conclusion

We report a difference in the prognostic value of lactate and BD on mortality. Three hours from the initiation of ECLS in patients with RCA, lactate should be preferred to BD to predict the efficiency of ECLS.

No effect of hyperoxia on outcome following major trauma

Purpose

Oxygen supplementation has previously been considered beneficial when managing critically ill patients in order to avoid hypoxia. However, in recent years, studies have shown that hyperoxia may be harmful in critical care patients. The aim of the study was to investigate whether hyperoxia within the first 24 hours of admission following major trauma is associated with 30-day in-hospital mortality.

Patients and methods

We conducted a retrospective database study of trauma patients admitted to the general intensive care unit at University Hospital Southampton from October 2008 to October 2014. Hyperoxia was defined as one arterial blood gas with a pO₂ ≥40.0 kPa during the first 24 hours of admission. Cox proportional hazards regression was used to compare 30-day in-hospital mortality between the two groups. HRs for death were calculated with 95% CIs and presented as both unadjusted and adjusted for age, sex, Acute Physiology and Chronic Health Evaluation II (APACHE II) score and number of arterial blood gases.

Results

In total, 1,462 patients had trauma as the cause for admission. Of these, 343 patients met the study inclusion criteria, of which 265 were defined as normoxic and the remaining 78 patients as hyperoxic. The cumulative in-hospital risk of death within 30 days was 7.8% (95% CI: 4.9%–12.5%) for the normoxia group and 9.7% (95% CI: 4.4 %–20.4%) for the hyperoxia group. The crude HR for 30-day in-hospital mortality was 1.15 (95% CI: 0.45–2.90) for hyperoxia compared to normoxia. Adjusting for APACHE II, age, sex and number of arterial blood gases yielded an adjusted HR of 30-day in-hospital mortality of 0.65 (95% CI: 0.24–1.73) for the hyperoxia group compared to the normoxia group.

Conclusion

In our convenience sample of 343 patients, hyperoxia within the first 24 hours following admission to intensive care with major trauma had no impact on 30-day in-hospital mortality.

Performance of injury severity measures in trauma research: a literature review and validation analysis of studies from low-income and middle-income countries

INTRODUCTION

Characterisation of injury severity is an important pillar of scientific research to measure and compare the outcomes. Although majority of injury severity measures were developed in high-income countries, many have been studied in low-income and middle-income countries (LMICs). We conducted this study to identify and characterise all injury severity measures, describe how widely and frequently they are used in trauma research from LMICs, and summarise the evidence on their performance based on empirical and theoretical validation​ analysis.

METHODS

First, a list of injury measures was identified through PubMed search. Subsequently, a systematic search of PubMed, Global Health and EMBASE was undertaken on LMIC trauma literature published from January 2006 to June 2016, in order to assess the application and performance of injury severity measures to predict in-hospital mortality. Studies that applied one or more global injury severity measure(s) on all types of injuries were included, with the exception of war injuries and isolated organ injuries.

RESULTS

Over a span of 40 years, more than 55 injury severity measures were developed. Out of 3862 non-duplicate citations, 597 studies from 54 LMICs were listed as eligible studies. Full-text review revealed 37 studies describing performance of injury severity measures for outcome prediction. Twenty-five articles from 13 LMICs assessed the validity of at least one injury severity measure for in-hospital mortality. Injury severity score was the most commonly validated measure in LMICs, with a wide range of performance (area under the receiver operating characteristic curve (AUROC) between 0.9 and 0.65). Trauma and Injury Severity Score validation studies reported AUROC between 0.80 and 0.98.

CONCLUSION

Empirical studies from LMICs frequently use injury severity measures, however, no single injury severity measure has shown a consistent result in all settings or populations and thus warrants validation studies for the diversity of LMIC population.

Use of CytoSorb in Traumatic Amputation of the Forearm and Severe Septic Shock

Severe trauma associated with later disability and mortality still constitutes a major health and socioeconomic problem throughout the world. While primary morbidity and mortality are mostly related to initial injuries and early complications, secondary lethality is strongly linked to the development of systemic inflammatory response syndrome, sepsis, and ultimately multiple organ dysfunction syndrome. We herein report on a 49-year-old male patient who was admitted to the hospital after a traumatic amputation of his right forearm that was cut off while working on a landfill. After initial treatment for shock, he received immediate replantation and was transferred to the ICU. Due to the anticipated risk of a complex infection, continuous renal replacement therapy in combination with CytoSorb was initiated. During the course of the combined treatment, a rapid improvement in hemodynamics was noticed, as well as a significant reduction of IL-6 and lactate levels. Despite a recurring septic episode and the necessity for amputation, the patient clinically stabilized and underwent complete recovery. The early treatment with a combination of CVVHDF and CytoSorb was accompanied by an attenuation of the systemic inflammatory reaction, which subsided without major or permanent organ damage, despite the impressive pathogen spectrum and the pronounced local damage.

Assessment of a portable lactate meter for field use in the white rhinoceros (<i>Ceratotherium simum</i>)

Blood lactate is a predictor of mortality in critically ill humans and animals. Handheld lactate meters have the potential to be used in the field to evaluate the condition of severely injured rhinoceroses but have not been compared with laboratory-based methods. Agreement between a handheld lactate meter and a laboratory method was assessed, as was the stability of rhino blood lactate in the anticoagulant sodium fluoride/potassium oxalate (fluoride/oxalate). Blood samples were obtained from 53 white rhinos that had been immobilised for management reasons. Lactate was measured by means of a handheld meter using whole blood in heparin (WBHEP), whole blood in fluoride/oxalate (WBFO) and fluoride/oxalate plasma (PFO). Results were recorded in both blood (BL) and plasma (PL) modes and compared to an established laboratory method for measuring plasma lactate. To assess the stability of lactate over time, blood lactate in fluoride/oxalate was measured on the handheld meter at intervals for up to 91 h. Agreement was best using WBFO in PL mode, with small bias (−0.16), tight 95% limits of agreement (LOA) (−1.46, 1.14) and a Pc (95% CI) of 0.97 (0.92, 0.99). The agreement was improved for all sample types when using the PL mode compared to the blood lactate (BL) mode. Blood lactate was stable in fluoride/oxalate for 91 h, with a mean change from baseline of 0.15 (−0.178, 0.478) mmol/L (mean, 95% CI). The handheld meter was found to be suitable for field use in white rhinos but provided more reliable results with the device in PL mode. Furthermore, rhino blood lactate was found to be stable in fluoride/oxalate for as long as 3 days.

Comparison of compensatory reserve and arterial lactate as markers of shock and resuscitation

BACKGROUND

During traumatic hemorrhage, the ability to identify shock and intervene before decompensation is paramount to survival. Lactate is extremely sensitive to shock, and its clearance has been demonstrated a useful gauge of shock and resuscitation status. Though lactate can be measured in the field, logistical constraints render it impractical in certain environments. The compensatory reserve represents a new clinical measurement reflecting the remaining capacity to compensate for hypoperfusion. We hypothesized the compensatory reserve index (CRI) would be an effective surrogate marker of shock and resuscitation compared to lactate.

METHODS

The CRI device was placed on consecutive patients meeting trauma center activation criteria and remained on the patient until discharge, admission, or transport to operating suite. All subjects had a lactate level measured as part of their routine admission metabolic analysis. Time-corresponding CRI and lactate values were matched in regards to initial and subsequent lactate levels. Mean time from lactate sample collection to data availability in the electronic medical record was calculated. Predictive capacity of CRI and lactate in predicting hemorrhage was determined by receiver-operator characteristic curve analysis. Correlation analysis was performed to determine if any association existed between changing CRI and lactate values.

RESULTS

Receiver-operator characteristic (ROC) curves were generated and area under the curve was 0.8052 and 0.8246 for CRI and lactate, respectively. There was no significant difference in each parameter's ability to predict hemorrhage (p = 0.8015). The mean duration from lactate sample collection to clinical availability was 44 minutes whereas CRI values were available immediately. Analysis of the concomitant change in serial CRI and lactate levels revealed a Spearman's correlation coefficient of -0.73 (p < 0.01).

CONCLUSION

CRI performed with equivalent predictive capacity to lactate with respect to identifying initial perfusion status associated with hemorrhage and subsequent resuscitation.

LEVEL OF EVIDENCE

Diagnostic, Level II.

Extremes of shock index predicts death in trauma patients

Context:

We noted a bimodal relationship between mortality and shock index (SI), the ratio of heart rate to systolic blood pressure.

Aims:

To determine if extremes of SI can predict mortality in trauma patients.

Settings and Designs:

Retrospective evaluation of adult trauma patients at a tertiary care center from 2000 to 2012 in the United States.

Materials and Methods:

We examined the SI in trauma patients and determined the adjusted mortality for patients with and without head injuries.

Statistical Analysis Used:

Descriptive statistics and multivariable logistic regression. Results: SI values demonstrated a U-shaped relationship with mortality. Compared with patients with a SI between 0.5 and 0.7, patients with a SI of <0.3 had an odds ratio for death of 2.2 (95% confidence interval [CI] 21.2–4.1) after adjustment for age, Glasgow Coma score, and injury severity score while patients with SI >1.3 had an odds ratio of death of 3.1. (95% CI 1.6–5.9). Elevated SI is associated with increased mortality in patients with isolated torso injuries, and is associated with death at both low and high values in patients with head injury.

Conclusion:

Our data indicate a bimodal relationship between SI and mortality in head injured patients that persists after correction for various co-factors. The distribution of mortality is different between head injured patients and patients without head injuries. Elevated SI predicts death in all trauma patients, but low SI values only predict death in head injured patients.

Validation of the Denver Emergency Department Trauma Organ Failure Score to Predict Post-Injury Multiple Organ Failure

BACKGROUND

Early recognition of trauma patients at risk for multiple organ failure (MOF) is important to reduce the morbidity and mortality associated with MOF. The objective of the study was to externally validate the Denver Emergency Department (ED) Trauma Organ Failure (TOF) Score, a 6-item instrument that includes age, intubation, hematocrit, systolic blood pressure, blood urea nitrogen, and white blood cell count, which was designed to predict the development of MOF within 7 days of hospitalization.

STUDY DESIGN

We performed a prospective multicenter study of adult trauma patients between November, 2011 and March, 2013. The primary outcome was development of MOF within 7 days of hospitalization, assessed using the Sequential Organ Failure Assessment Score. Hierarchical logistic regression analysis was performed to determine associations between the Denver ED TOF Score and MOF. Discrimination was assessed and quantified using a receiver operating characteristics (ROC) curve. The predictive accuracy of the Denver ED TOF score was compared with attending emergency physician estimation of the likelihood of MOF.

RESULTS

We included 2,072 patients with a median age of 46 years (interquartile range [IQR] 30 to 61 years); 68% were male. The median Injury Severity Score was 9 (IQR 5 to 17), and 88% of patients had blunt mechanism injury. Among participants, 1,024 patients (49%) were admitted to the ICU, and 77 (4%) died. Multiple organ failure occurred in 120 (6%; 95% CI 5% to 7%) patients and of these, 37 (31%; 95% CI 23% to 40%) died. The area under the ROC curve for the Denver ED TOF Score prediction of MOF was 0.89 (95% CI 0.86 to 0.91) and for physician estimation of the likelihood of MOF was 0.78 (95% CI 0.73 to 0.83).

CONCLUSIONS

The Denver ED TOF Score predicts development of MOF within 7 days of hospitalization. Its predictive accuracy outperformed attending emergency physician estimation of the risk of MOF.

The predictive value of initial serum lactate in trauma patients

Trauma patients require early assessment of injury severity. Trauma scores, although well validated, can be unwieldy in the emergency clinical setting. We sought to evaluate the prognostic value of initial serum lactate (ISL) for mortality, operative intervention (OI), and intensive care unit admission (ICUA) in trauma patients. We conducted an institutional review board-approved retrospective study. We reviewed all trauma patients between January 2007 and June 2012 in our prospectively maintained database. We included only adults whose ISL had been drawn within the first 35 min after arrival. We included only those patients whose interval between injury and arrival was within 24 h. Survivors and nonsurvivors were compared using logistic regression, Mann-Whitney U, and chi-square tests. Discriminating ability of ISL for mortality was assessed with receiver operating characteristic analysis. Our secondary outcomes (ICUA and OI) were evaluated with logistic regression test and receiver operating characteristic analysis. A total of 1,941 patients were included. Overall mortality was 6.2%. Median ISL was 32 mg/dL (interquartile range, 17 - 62) for nonsurvivors versus 21 mg/dL (interquartile range, 14 - 32) for survivors (P < 0.001). In multivariate analysis, ISL was a significant covariate for mortality (P = 0.015). The odds ratio was 1.010 (95% confidence interval, 1.002 - 1.019). The area under the curve was 0.63. The ISL was a significant covariate for OI (P = 0.033). The ISL did not reach significance for ICUA. The ISL is an easily measured, rapid, and inexpensive test that can help to quickly stratify injury severity in trauma patients. We have found that ISL, when used in strictly selected patients, can predict OI and mortality.

Validation and analysis of prognostic scoring systems for critically ill patients with cirrhosis admitted to ICU

Introduction

The number of patients admitted to ICU who have liver cirrhosis is rising. Current prognostic scoring tools to predict ICU mortality have performed poorly in this group. In previous research from a single centre, a novel scoring tool which modifies the Child-Turcotte Pugh score by adding Lactate concentration, the CTP + L score, is strongly associated with mortality. This study aims to validate the use of the CTP + L scoring tool for predicting ICU mortality in patients admitted to a general ICU with cirrhosis, and to determine significant predictive factors for mortality with this group of patients. This study will also explore the use of the Royal Free Hospital (RFH) score in this cohort.

Methods

A total of 84 patients admitted to the Glasgow Royal Infirmary ICU between June 2012 and Dec 2013 with cirrhosis were included. An additional cohort of 115 patients was obtained from two ICUs in London (St George’s and St Thomas’) collected between October 2007 and July 2009. Liver specific and general ICU scoring tools were calculated for both cohorts, and compared using area under the receiver operating characteristic (ROC) curves. Independent predictors of ICU mortality were identified by univariate analysis. Multivariate analysis was utilised to determine the most predictive factors affecting mortality within these patient groups.

Results

Within the Glasgow cohort, independent predictors of ICU mortality were identified as Lactate (p < 0.001), Bilirubin (p = 0.0048), PaO₂/FiO₂ Ratio (p = 0.032) and PT ratio (p = 0.012). Within the London cohort, independent predictors of ICU mortality were Lactate (p < 0.001), PT ratio (p < 0.001), Bilirubin (p = 0.027), PaO₂/FiO₂ Ratio (p = 0.0011) and Ascites (p = 0.023). The CTP + L and RFH scoring tools had the highest ROC value in both cohorts examined.

Conclusion

The CTP + L and RFH scoring tool are validated prognostic scoring tools for predicting ICU mortality in patients admitted to a general ICU with cirrhosis.

Denver ED Trauma Organ Failure Score outperforms traditional methods of risk stratification in trauma

BACKGROUND

Early identification of trauma patients at risk for inhospital mortality may facilitate goal-directed resuscitation and secondary triage to improve outcomes. The objective of this study was to compare prognostic accuracies of the Denver Emergency Department (ED) Trauma Organ Failure (TOF) Score, ED Sequential Organ Failure Assessment (SOFA) score, and ED base deficit and ED lactate for inhospital mortality in adult trauma patients.

METHODS

Consecutive adult trauma patients from 2005 to 2008 from the Denver Health Trauma Registry were included. Prognostic accuracies of the Denver ED TOF Score, ED SOFA score, ED base deficit, and ED lactate for inhospital mortality were evaluated with receiver operating characteristic curves.

RESULTS

Of the 4355 patients, the median age was 37 years (interquartile range [IQR], 26-51 years), median Injury Severity Score was 9 (IQR, 4-16), and 81% had blunt mechanisms. In addition, 38% (1670 patients) were admitted to the intensive care unit with a median intensive care unit length of stay of 2.5 days (IQR, 1-8 days), and 3% (138 patients) died. The areas under the receiver operating characteristic curves for the Denver ED TOF, ED lactate, ED base deficit, and ED SOFA were 0.94 (95% confidence interval [CI], 0.94-0.96), 0.88 (95% CI, 0.85-0.91), 0.82 (95% CI, 0.78-0.86), and 0.78 (95% CI, 0.73-0.82), respectively.

CONCLUSIONS

The Denver ED TOF Score more accurately predicts inhospital mortality in adult trauma patients compared to the ED SOFA score, ED base deficit, or ED lactate. The Denver ED TOF Score may help identify patients early who are at risk for mortality, allowing for targeted resuscitation and secondary triage to improve outcomes.

Perioperative Acid-Base and Electrolyte Disturbances

Obtaining and interpreting blood gas and electrolyte levels is essential in the management of perioperative veterinary patients. Metabolic and electrolyte alterations are common in critically ill surgical patients, and can lead to alterations in cardiovascular function, neurologic status, respiratory function, and even response to various drug therapies. Several common perioperative conditions are discussed in this article, including metabolic disturbances, electrolyte abnormalities (hyponatremia and hypernatremia, hyperkalemia), and respiratory abnormalities.

Using population-based critical care data to evaluate trauma outcomes

BACKGROUND

The analysis of mortality is an integral part of the evaluation of trauma care. When specific data are not available, general prediction models can be used to adjust for case mix. The aim of this study was to evaluate the feasibility of conducting a population-based analysis of trends in trauma mortality, using critical care audit data, and to investigate whether such data could provide a benchmark for the assessment of service reconfiguration.

METHODS

Retrospective cohort study of adult trauma patients, requiring admission to a critical care unit in Scotland, 2002-2011, using nationally collected data. Results are presented as standardised mortality ratios of observed mortality divided by APACHE II predicted mortality. Tests for trends in numbers and ratios over time were performed using linear regression.

FINDINGS

4503 patients were identified. There was a significant increase in the number of trauma patients admitted per year (p = 0.011). The median predicted probability of in-hospital death was 7% (interquartile range 1-13%), against an actual mortality was 11.6%. There was no significant change in the standardised mortality ratios of trauma patients (p = 0.1224).

CONCLUSIONS

This study demonstrated the feasibility of utilising critical care unit audit data for analysing outcomes from trauma care. It also showed the potential of such an approach to establish a baseline against which to compare the impact of future service reconfiguration. In contrast to healthcare systems with regionalised trauma care, there appears to have been little change in the mortality of trauma patients requiring critical care unit admission in Scotland.

Comparison of APACHE II and three abbreviated APACHE II scores for predicting outcome among emergency trauma patients

OBJECTIVE

to compare the ability of the APACHE II score and three different abbreviated APACHE II scores: simplified APACHE II (s-APACHE II), Rapid Acute Physiology score (RAPS) and Rapid Emergency Medicine score to evaluate in-hospital mortality of trauma patients at the emergency department (ED).

METHODS

retrospective analysis of a prospective cohort study. All patients' victims of trauma admitted to the ED, during a 5 months period. For all entries to the ED, APACHE II score was calculated. APACHE II system was abbreviated by excluding the laboratory data to calculate s-APACHE II score for each patient. Individual data were reanalyzed to calculate RAPS and REMS. APACHE II score and its subcomponents were collected, and in-hospital mortality was assessed. The area under the receiver operating characteristic (AUROC) curve was used to determine the predictive value of each score.

RESULTS

163 patients were analyzed. In-hospital mortality rate was 10.4%. s-APACHE II, RAPS and REMS scores were correlated with APACHE II score (r2= 0.96, r2= 0.82, r2= 0.92; p < 0.0001). Scores had similar accuracy in predicting mortality ([AUROC 0.777 [95% CI 0.705 to 0.838] for APACHE II, AUROC 0.788 [95% CI 0.717 to 0.848] for s-APACHE II, AUROC 0.806 [95% CI 0.737 to 0.864] for RAPS, AUROC 0.761 [95% CI 0.688 to 0.824] for REMS.

CONCLUSION

abbreviated APACHE II scores have similar ability to evaluate in-hospital mortality of emergency trauma patients in comparison to APACHE II score.

Utility of admission serum lactate in pediatric trauma

BACKGROUND/PURPOSE

Serum lactate measurement has a predictive value in adult trauma. To date, there has been no prospective analysis of the predictive value of admission serum lactate in pediatric trauma.

METHODS

Admission serum lactate was prospectively measured over a two year period on all children under age 15 years who met trauma alert criteria at an urban Level 1 trauma center. Elevated serum lactate (>2.0 mmol/L) was correlated with Injury Severity Scores (ISS), injury types, and hospital outcomes.

RESULTS

A total of 277 injured children with admission lactate measurements were evaluated. Patients with elevated lactate had higher mean ISS than those with normal lactate (12.8 vs. 5.1, p<0.01), and increased need for intubation, major procedures and ICU admission. Elevated lactate was associated with low specificity (54.4%), moderate sensitivity (86.7%) and high negative predictive value (94.5%) for detecting injury (ISS>15). Lactate measurements over 4.7 mmol/L were highly specific (95.8%) for injury.

CONCLUSIONS

Elevated admission venous lactate level is associated with injury and outcomes, but lacks adequate sensitivity and specificity. Lactate over 4.7 mmol/L is strongly suggestive of severe injury, while lactate below 2.0 mmol/L is reassuring for not having injury. Lactates between 2.0 and 4.7 mmol/L remain indeterminate in predictive potential for injury or outcomes.

Lactate on emergency department arrival as a predictor of mortality and site-of-care in pneumonia patients: a cohort study

OBJECTIVE

To investigate the predictive performance of lactate, CURB-65, and a combination of lactate and CURB-65 (LAC-CURB-65) for mortality, hospitalisation and intensive care unit (ICU) admission in pneumonia patients in the emergency department (ED).

METHODS

Consecutive adult patients with pneumonia presenting from January 2012 to May 2014 were divided into low-, moderate- and high-risk groups according to lactate (<2.0, 2.0-4.0, >4.0 mmol/L), CURB-65 (≤1, 2, ≥3) and LAC-CURB-65 (patients with two low risks, any moderate risk, any high risk) values. Mortality, hospitalisation and ICU admission rates were compared between risk classes.

RESULTS

Of 1641 patients, 861 (53%) were hospitalised (38% to a general ward, 15% to the ICU) while the remaining 780 (47%) were treated as outpatients or observed in the ED. 547/1641 (33%) patients died within 28 days. Lactate and CURB-65 were higher in patients who died, were hospitalised or were admitted to the ICU compared with patients who were not (p<0.001). Lactate and CURB-65 independently predicted outcomes. The performance of lactate in predicting 28-day mortality, hospitalisation and ICU admission was higher than that of CURB-65 (p<0.01). For LAC-CURB-65, patients at low or moderate risk had mortality rates of 2% and 14%, respectively, and hospitalisation rates of 15% and 40%, respectively, while none were admitted to ICU. Patients at high risk had the highest mortality (52%), hospitalisation (70%) and ICU admission rates (27%).

CONCLUSIONS

Lactate is superior to CURB-65 in predicting mortality, hospitalisation and ICU admission in pneumonia patients in the ED. LAC-CURB-65 significantly improved the predictive value of CURB-65.

The effect of ethanol on lactate and base deficit as predictors of morbidity and mortality in trauma

OBJECTIVE

The objective of this study was to assess the predictive value of lactate and base deficit in determining outcomes in trauma patients who are positive for ethanol.

METHODS

Retrospective cohort study of patients admitted to a level 1 trauma center between 2005 and 2014. Adult patients who had a serum ethanol, lactate, base deficit, and negative urine drug screen obtained upon presentation were included.

RESULTS

Data for 2482 patients were analyzed with 1127 having an elevated lactate and 1092 an elevated base deficit. In these subgroups, patients with a positive serum ethanol had significantly lower 72-hour mortality, overall mortality, and hospital length of stay compared with the negative ethanol group. Abnormal lactate (odds ratio [OR], 2.607; 95% confidence interval [CI], 1.629-4.173; P = .000) and base deficit (OR, 1.917; 95% CI, 1.183-3.105; P = .008) were determined to be the strongest predictors of mortality in the ethanol-negative patients. Injury Severity Score was found to be the lone predictor of mortality in patients positive for ethanol (OR, 1.104; 95% CI, 1.070-1.138; P = .000). Area under the curve and Youden index analyses supported a relationship between abnormal lactate, base deficit, and mortality in ethanol-positive patients when the serum lactate was greater than 4.45 mmol/L and base deficit was greater than -6.95 mmol/L.

CONCLUSIONS

Previously established relationships between elevated lactate, base deficit, and outcome do not remain consistent in patients presenting with positive serum ethanol concentrations. Ethanol skews the relationship between lactate, base deficit, and mortality thus resetting the threshold in which lactate and base deficit are associated with increased mortality.

Initial venous lactate levels in patients with isolated penetrating extremity trauma: a retrospective cohort study

INTRODUCTION

Elevated initial lactate levels have been shown to be associated with severe injury in trauma patients, but some patients who do not appear to be in shock also presented with elevated lactate levels. We hypothesized that in hemodynamically stable patients with isolated penetrating extremity trauma, initial lactate level does not predict clinically significant bleeding.

METHODS

A 5-year institutional database review was performed. Hemodynamically stable patients (HR < 101, SBP > 90) with isolated penetrating extremity trauma with an initial lactate sent were included. The exposure of interest was captured as a dichotomous variable by initial lactate level normal (N ≤ 2.2 mEq/L), elevated (E > 2.2 mEq/L). The primary outcome measurement was clinically significant bleeding, defined by need for intervention (operation, angioembolization, or transfusion) or laboratory evidence of bleeding (presenting Hg < 7 g/dL, or Hg decrease by >2 g/dL/24 h). Chi-squared and Mann-Whitney tests were used to compare variables.

RESULTS

A total of 132 patients were identified. There were no differences in demographics or mechanism of injury between the N (n = 43, 7%) and E (n = 89, 14%) groups. Median lactate levels were 1.6 (IQR 1.2-1.9) mEq/dL vs. 3.8 (IQR 2.8-5.2) in the N and E groups, p < 0.001. Lactate was elevated in 89 (67%) patients but was not associated with clinically significant bleeding (37% elevated vs. 39 % not elevated p = 0.82).

CONCLUSIONS

In hemodynamically stable patients with isolated penetrating trauma to the extremity, elevated initial venous lactate levels (>2.2 mEq/L) are not associated with bleeding or need for interventions. Clinical judgment remains the gold standard for evaluation and management of these patients.

Arterial lactate improves the prognostic performance of severity score systems in septic patients in the ED

OBJECTIVE

To evaluate the prognostic performance of lactate in septic patients in the emergency department (ED) and investigate how to add lactate to the traditional score systems.

METHODS

This was a single-centered, prospective, observational cohort study conducted in ED of Beijing Chao-Yang Hospital. The study enrolled adult septic patients admitted to the ED. Arterial lactate was measured in every patient. Acute Physiology and Chronic Health Evaluation (APACHE) II, Sequential Organ Failure Assessment (SOFA), and Mortality in Emergency Department Sepsis (MEDS) scores were calculated on ED arrival. The primary outcome was 28-day mortality.

RESULTS

The average levels of lactate, MEDS, APACHE II, and SOFA were much higher in nonsurvivors than in survivors (P < .001), and they were the independent predictors of 28-day mortality. Area under receiver operating characteristic (AUC) curves of MEDS, APACHE II, SOFA, and lactate were 0.74, 0.74, 0.75, and 0.79, respectively. The AUCs of combination lactate and MEDS, APACHE II, and SOFA were 0.81, 0.81, and 0.82, respectively and were much higher than that of score systems alone (P < .05). The AUCs of modified MEDS, APACHE II, and SOFA were 0.80, 0.80, and 0.81, respectively. The prognostic value of the modified score systems was superior to the original score systems and similar to the combination of the lactate and original score systems.

CONCLUSIONS

Lactate is a prognostic predictor in septic patients in the ED, and it may improve the performance of APACHE II, SOFA, and MEDS scores in predicting mortality.

Prediction of postinjury multiple-organ failure in the emergency department: development of the Denver Emergency Department Trauma Organ Failure score

BACKGROUND

Multiple-organ failure (MOF) is common among the most seriously injured trauma patients. The ability to easily and accurately identify trauma patients in the emergency department at risk for MOF would be valuable. The aim of this study was to derive and internally validate an instrument to predict the development of MOF in adult trauma patients using clinical and laboratory data available in the emergency department.

METHODS

We enrolled consecutive adult trauma patients from 2005 to 2008 from the Denver Health Trauma Registry, a prospectively collected database from an urban Level 1 trauma center. Multivariable logistic regression was used to develop a clinical prediction instrument. The outcome was the development of MOF within 7 days of admission as defined by the Sequential Organ Failure Assessment (SOFA) score. A risk score was created from the final regression model by rounding the regression β coefficients to the nearest integer. Calibration and discrimination were assessed using 10-fold cross-validation.

RESULTS

A total of 4,355 patients were included in this study. The median age was 37 years (interquartile range [IQR], 26-51 years), and 72% were male. The median Injury Severity Score (ISS) was 9 (IQR, 4-16), and 78% of the patients had blunt injury mechanisms. MOF occurred in 216 patients (5%; 95% confidence interval, 4-6%). The final risk score included patient age, intubation, systolic blood pressure, hematocrit, blood urea nitrogen, and white blood cell count and ranged from 0 to 9. The prevalence of MOF increased in an approximate exponential fashion as the score increased. The model demonstrated excellent calibration and discrimination (calibration slope, 1.0; c statistic, 0.92).

CONCLUSION

We derived a simple, internally valid instrument to predict MOF in adults following trauma. The use of this score may allow early identification of patients at risk for MOF and result in more aggressive targeted resuscitation and improved resource allocation.

LEVEL OF EVIDENCE

Prognostic and epidemiologic study, level III.

Etiology and therapeutic approach to elevated lactate levels

Lactate levels are commonly evaluated in acutely ill patients. Although most often used in the context of evaluating shock, lactate levels can be elevated for many reasons. While tissue hypoperfusion may be the most common cause of elevation, many other etiologies or contributing factors exist. Clinicians need to be aware of the many potential causes of lactate level elevation as the clinical and prognostic importance of an elevated lactate level varies widely by disease state. Moreover, specific therapy may need to be tailored to the underlying cause of elevation. The present review is based on a comprehensive PubMed search between the dates of January 1, 1960, to April 30, 2013, using the search term lactate or lactic acidosis combined with known associations, such as shock, sepsis, cardiac arrest, trauma, seizure, ischemia, diabetic ketoacidosis, thiamine, malignancy, liver, toxins, overdose, and medication. We provide an overview of the pathogenesis of lactate level elevation followed by an in-depth look at the varied etiologies, including medication-related causes. The strengths and weaknesses of lactate as a diagnostic/prognostic tool and its potential use as a clinical end point of resuscitation are discussed. The review ends with some general recommendations on the management of patients with elevated lactate levels.

Trauma and aggressive homeostasis management

Homeostasis refers to the capacity of the human body to maintain a stable constant state by means of continuous dynamic equilibrium adjustments controlled by a medley of interconnected regulatory mechanisms. Patients who sustain tissue injury, such as trauma or surgery, undergo a well-understood reproducible metabolic and neuroendocrine stress response. This review discusses 3 issues that concern homeostasis in the acute care of trauma patients directly related to the stress response: hyperglycemia, lactic acidosis, and hypothermia. There is significant reason to question the "conventional wisdom" relating to current approaches to restoring homeostasis in critically ill and trauma patients.

Does Acute Physiology and Chronic Health Evaluation II Provide a Valid Metric to Directly Compare Disease Severity in Trauma versus Surgical Intensive Care Unit Patients?

The Acute Physiology and Chronic Health Evaluation II (APACHE II) score has never been validated to risk-adjust between critically ill trauma (TICU) and general surgical (SICU) intensive care unit patients, yet it is commonly used for such a purpose. To study this, we evaluated risk of death in TICU and SICU patients with pneumonia. We hypothesized that mortality for a given APACHE II would be significantly different and that using APACHE II to directly compare TICU and SICU patients would not be appropriate. We conducted a retrospective review of patients admitted to the TICU or SICU at a tertiary medical center over an 18-month period with pneumonia. Admission APACHE II scores, in-hospital mortality, demographics, and illness characteristics were recorded. One hundred eighty patients met inclusion criteria, 116 in the TICU and 64 in the SICU. Average APACHE II scores were not significantly different in the TICU versus SICU (25 vs 24; P = 0.4607), indicating similar disease severity; overall mortality rates, however, were significantly different (24 vs 50%; P = 0.0004). Components of APACHE II, which contributed to this mortality differential, were Glasgow Coma Score, age, presence of chronic health problems, and operative intervention. APACHE II fails to provide a valid metric to directly compare the severity of disease between TICU and SICU patients with pneumonia. These groups represent distinct populations and should be separated when benchmarking outcomes or creating performance metrics in ICU patients. Improved severity scoring systems are needed to conduct clinically relevant and methodologically valid comparisons between these unique groups.

Utility of admission physiology in the surgical triage of isolated ballistic battlefield torso trauma

BACKGROUND

An assessment of hemodynamic stability is central to surgical decision-making in the management of battlefield ballistic torso trauma (BBTT).

AIMS

To analyse the utility of admission physiological parameters in characterising hemodynamic stability.

SETTINGS AND DESIGN

A retrospective analysis of consecutive admissions, with BBTT, to forward surgical facility in Afghanistan.

MATERIALS AND METHODS

The cohorts' admission physiology, need for operative intervention, and mortality data were collected retrospectively. The cohort was divided into patients requiring surgery for Life-Threatening Torso Hemorrhage (LTTH) and those not requiring immediate surgery (non-LTTH).

STATISTICAL ANALYSIS

Parameters were compared using two sample t tests, Mann-Whitney, Fisher's exact, and Chi-square tests. Receiver operator characteristic curves were used to identify significant parameters and determine optimum cut-off values.

RESULTS

A total of 103 patients with isolated BBTT were identified: 44 in the LTTH group and 59 in the non-LTTH group. The mean New Injury Severity Score ± Standard Deviation (NISS±SD) was 28±14 and 13±12, respectively. The heart rate, systolic blood pressure (SBP), pulse pressure, shock index (SI=heart rate/SBP) and base excess were analysed. SI correlated best with the need for surgical torso hemorrhage control, P<0.05. An optimal cut-off of 0.9 was identified, producing a positive and negative predictive value of 81% and 82%, respectively.

CONCLUSIONS

Shock index (SI) is a useful parameter for helping military surgeons triage BBTT, identifying patients requiring operative torso hemorrhage control. SI performance requires a normal physiological response to hypovolemia, and thus should always be considered in clinical context.

Serial lactate and admission SOFA scores in trauma: an analysis of predictive value in 724 patients with and without traumatic brain injury

OBJECTIVE

Arterial lactate, base excess (BE), lactate clearance, and Sequential Organ Failure Assessment (SOFA) score have been shown to correlate with outcome in severely injured patients. The goal of the present study was to separately assess their predictive value in patients suffering from traumatic brain injury (TBI) as opposed to patients suffering from injuries not related to the brain.

MATERIALS AND METHODS

A total of 724 adult trauma patients with an Injury Severity Score (ISS) ≥ 16 were grouped into patients without TBI (non-TBI), patients with isolated TBI (isolated TBI), and patients with a combination of TBI and non-TBI injuries (combined injuries). The predictive value of the above parameters was then analyzed using both uni- and multivariate analyses.

RESULTS

The mean age of the patients was 39 years (77 % males), with a mean ISS of 32 (range 16-75). Mortality ranged from 14 % (non-TBI) to 24 % (combined injuries). Admission and serial lactate/BE values were higher in non-survivors of all groups (all p < 0.01), but not in patients with isolated TBI. Admission SOFA scores were highest in non-survivors of all groups (p = 0.023); subsequently septic patients also showed elevated SOFA scores (p < 0.01), except those with isolated TBI. In this group, SOFA score was the only parameter which showed significant differences between survivors and non-survivors. Receiver operating characteristic (ROC) analysis revealed lactate to be the best overall predictor for increased mortality and further septic complications, irrespective of the leading injury.

CONCLUSION

Lactate showed the best performance in predicting sepsis or death in all trauma patients except those with isolated TBI, and the differences were greatest in patients with substantial bleeding. Following isolated TBI, SOFA score was the only parameter which could differentiate survivors from non-survivors on admission, although the SOFA score, too, was not an independent predictor of death following multivariate analysis.

The utility of acute physiology and chronic health evaluation II scores for prediction of mortality among intensive care unit (ICU) and non-ICU patients with methicillin-resistant Staphylococcus aureus bacteremia

OBJECTIVE

Bloodstream infections due to methicillin-resistant Staphylococcus aureus (MRSA) have been associated with significant risk of in-hospital mortality. The acute physiology and chronic health evaluation (APACHE) II score was developed and validated for use among intensive care unit (ICU) patients, but its utility among non-ICU patients is unknown. The aim of this study was to determine the ability of APACHE II to predict death at multiple time points among ICU and non-ICU patients with MRSA bacteremia.

DESIGN

Retrospective cohort study.

PARTICIPANTS

Secondary analysis of data from 200 patients with MRSA bacteremia at 2 hospitals.

METHODS

Logistic regression models were constructed to predict overall in-hospital mortality and mortality at 48 hours, 7 days, 14 days, and 30 days using APACHE II scores separately in ICU and non-ICU patients. The performance of APACHE II scores was compared with age adjustment alone among all patients. Discriminatory ability was assessed using the c-statistic and was compared at each time point using χ(2) tests. Model calibration was assessed using the Hosmer-Lemeshow goodness-of-fit test.

RESULTS

APACHE II was a significant predictor of death at all time points in both ICU and non-ICU patients. Discrimination was high in all models, with c-statistics ranging from 0.72 to 0.84, and was similar between ICU and non-ICU patients at all time points. APACHE II scores significantly improved the prediction of overall and 48-hour mortality compared with age adjustment alone.

CONCLUSIONS

The APACHE II score may be a valid tool to control for confounding or for the prediction of death among ICU and non-ICU patients with MRSA bacteremia.

Prognostic value of admission serum lactate concentrations in intensive care unit patients

BACKGROUND

Although blood lactate concentrations have an established prognostic value in circulatory shock or after cardiac arrest, their relationship with morbidity and length of stay in general intensive care unit (ICU) populations has not been well defined.

METHODS

This study included all 433 patients (246 surgical and 187 medical) consecutively admitted to the Department of medico-surgical intensive care. Hyperlactataemia was defined as a serum lactate concentration > or = 2 mEq/l.

RESULTS

On admission, 195 patients (45%) had hyperlactataemia. Hyperlactataemic patients had higher Acute Physiology and Chronic Health Evaluation (APACHE) II (13.3 +/- 6.9 vs 10.0 +/- 5.2) and Sequential Organ Failure Assessment (SOFA) (5.3 +/- 3.3 vs 3.3 +/- 2.3) scores than patients with normal lactate concentrations (both p < 0.01). There was no overall difference in length of ICU stay (LOS) between the two groups but survivors in the hyperlactataemic group had a longer LOS than survivors in the normal lactate group, whereas hyperlactataemic non-survivors had a shorter LOS than normal lactate non-survivors. Mortality was 9% in patients with normal lactate concentrations and 23% in hyperlactataemic patients. The mortality rate increased with increasing lactate concentrations, from 17% in patients with lactate concentrations from 2-4 mEq/l to 64% in those with concentrations more than 8 mEq/l. Non-survivors had higher lactate concentrations than survivors on admission, and after 24 and 48 hours. Risk factors for developing hyperlactataemia that were present on admission were SOFA score > 5, mean arterial blood pressure less than 70 mmHg, blood sugar greater than 110 mg/dl, and current use of vasopressors.

CONCLUSIONS

Our study documents a direct relationship between the serum lactate level on ICU admission and not only the risk of death in ICU but also the length of ICU stay. Hyperlactataemic survivors have a longer LOS and non-survivors a shorter LOS than normal lactate survivors and non-survivors, respectively.

Severe blunt trauma in dogs: 235 cases (1997-2003)

OBJECTIVE

To evaluate population characteristics, injuries, emergency diagnostic testing, and outcome of dogs with blunt trauma requiring intensive care in an urban hospital.

DESIGN

Retrospective study 1997-2003.

SETTING

All data obtained from the University of Pennsylvania - Matthew J. Ryan Veterinary Hospital.

ANIMALS

Dogs admitted to the intensive care unit for treatment following blunt trauma.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of the 235 dogs that met inclusion criteria, 206 (88%) survived and 29 (12%) did not survive. Blunt vehicular trauma accounted for 91.1% of cases. Mild hyperglycemia and hyperlactatemia was common in both survivors and nonsurvivors. The chest was the most common region traumatized and the prevalence of polytrauma was 72.3%. Initial weight, vital signs, PCV, total plasma protein, BUN, glucose, lactate, acid-base status, and electrolytes did not differ between survivors and nonsurvivors. Nonsurvivors were significantly more likely to have had head trauma (P=0.008), cranium fractures (P<0.001), recumbency at admission (P<0.001), development of hematochezia (P<0.001), clinical suspicion of acute respiratory distress syndrome (P<0.001), disseminated intravascular coagulation (P<0.001), multiorgan dysfunction syndrome (P<0.001), development of pneumonia (P<0.001), positive-pressure ventilation (P<0.001), vasopressor use (P<0.001), and cardiopulmonary arrest (P<0.001).

CONCLUSIONS

Outcome of severe blunt trauma in dogs treated with intensive care is very good. Despite the high survival rate, several features associated with poor outcome were identified. Neither admission lactate nor glucose was able to predict outcome.

Early serum procalcitonin, interleukin-6, and 24-hour lactate clearance: useful indicators of septic infections in severely traumatized patients

BACKGROUND

Elevated lactate and interleukin-6 (IL-6) levels were shown to correlate with mortality and multiple organ dysfunction in severely traumatized patients. The purpose of this study was to test whether an association exists between 24-hour lactate clearance, IL-6 and procalcitonin (PCT) levels, and the development of infectious complications in trauma patients.

METHODS

A total of 1757 consecutive trauma patients with an Injury Severity Score (ISS) > 16 admitted over a 10-year period were retrospectively analyzed over a 21-day period. Exclusion criteria included death within 72 h of admission (24.5%), late admission > 12 h after injury (16%), and age < 16 years (0.5%). Data are stated as the median (range).

RESULTS

Altogether, 1032 trauma patients (76.2% male) with an average age of 38 years, a median ISS of 29 (16-75), and an Acute Physiology, Age, and Chronic Health Evaluation (APACHE) II score of 14 (0-40) were evaluated. The in-hospital mortality (>3 days) was 10%. Patients with insufficient 24-hour lactate clearance had a high rate of overall mortality and infections. Elevated early serum procalcitonin on days 1 to 5 after trauma was strongly associated with the subsequent development of sepsis (p < 0.01) but not with nonseptic infections. The kinetics of IL-6 were similar to those of PCT but did differentiate between infected and noninfected patients after day 5.

CONCLUSIONS

This study demonstrates that elevated early procalcitonin and IL-6 levels and inadequate 24-hour lactate clearance help identify trauma patients who develop septic and nonseptic infectious complications. Definition of specific cutoff values and early monitoring of these parameters may help direct early surgical and antibiotic therapy and reduce infectious mortality.

Revisiting the validity of APACHE II in the trauma ICU: improved risk stratification in critically injured adults

BACKGROUND

Quality and benchmarking initiatives highlight the need for accurate stratified risk adjustment. The stratification of trauma patients has relied on scores specific to trauma populations. While the Acute Physiologic and Chronic Health Evaluation (APACHE) II score has been considered "invalid" in the trauma population, we hypothesized that APAHCE II would more accurately predict outcomes in critically injured patients in whom commonly used trauma scores have inherent limitations.

METHODS

A prospective cohort of critically injured patients was enrolled. Severity scores and their sub-components were collected, and in-hospital mortality was assessed. The area under the receiver operating characteristic (AUROC) curve was used to determine the predictive value of each score. Logistic regression estimated the odds of death associated with incremental changes in severity scores and their subcomponents.

RESULTS

1019 patients were available for analysis. APACHE II was the best predictor of mortality (AUROC 0.77 versus AUROC 0.54 for ISS and 0.64 for TRISS). A unit increase in APACHE II was associated with an OR of death of 1.18 (95% CI 1.14-1.22). The components of APACHE II that contributed the most to its accuracy included temperature, serum creatinine and the Glasgow Coma Scale (GCS).

CONCLUSION

Critically injured patients have physiologic derangements not accurately accounted for by commonly used trauma scores. In this subset a more general ICU scoring system is useful for risk adjustment for research, administrative and quality improvement purposes.

Venous glucose and arterial lactate as biochemical predictors of mortality in clinically severely injured trauma patients--a comparison with ISS and TRISS

BACKGROUND

Early assessment of injury severity is important in trauma. Trauma scores are calculated after the fact and are useful for audit and research, but not in the emergency clinical setting. Glucose metabolism is altered in trauma, and we hypothesised that alterations in glucose and lactate levels would be an early predictor of mortality.

METHODS

Review of trauma registry data identified 1197 patients between May 2000 and September 2006 who had a trauma-team call out. Data collected included trauma scores, venous glucose (gluc), and arterial lactate (lact) on arrival. The predictive value of these variables was compared by ROC curves.

RESULTS

The mortality rate for patients with gluc >11.0mmol/L was 13.4% compared to 1.8% in those with gluc <or=11.0mmol/L (p<0.0001). Gluc had a specificity of 93.2% and a sensitivity of 37.9% for death. 13.0% of patients with lact >2.0mmol/L died, versus 2.7% with lact <or=2.0mmol/L, (p0.0003, specificity 56.8% and sensitivity 81.0%). Glucose was the better biochemical predictor of mortality compared to lactate (ROC area 0.845 and 0.716, respectively). The TRISS (trauma and injury severity score) was a very accurate predictor (ROC 0.963), whereas the ISS (injury severity score) significantly less so (ROC 0.854). There was a significant correlation between gluc, ISS, and TRISS (p 0.01), as well as lactate and ISS (p 0.01).

CONCLUSION

Glucose and lactate can predict mortality in severe trauma. The predictive value of glucose is comparable to that of ISS, and can be more easily employed in the clinical setting.