Triage vital signs do not correlate with serum lactate or base deficit, and are less predictive of operative intervention in penetrating trauma patients: a prospective cohort study

HEMORRHAGIC SHOCK ASSESSED BY TISSUE MICROCIRCULATORY MONITORING: A NARRATIVE REVIEW

ABSTRACT

Hemorrhagic shock (HS) is a common complication after traumatic injury. Early identification of HS can reduce patients' risk of death. Currently, the identification of HS relies on macrocirculation indicators such as systolic blood pressure and heart rate, which are easily affected by the body's compensatory functions. Recently, the independence of the body's overall macrocirculation from microcirculation has been demonstrated, and microcirculation indicators have been widely used in the evaluation of HS. In this study, we reviewed the progress of research in the literature on the use of microcirculation metrics to monitor shock. We analyzed the strengths and weaknesses of each metric and found that microcirculation monitoring could not only indicate changes in tissue perfusion before changes in macrocirculation occurred but also correct tissue perfusion and cell oxygenation after the macrocirculation index returned to normal following fluid resuscitation, which is conducive to the early prediction and prognosis of HS. However, microcirculation monitoring is greatly affected by individual differences and environmental factors. Therefore, the current limitations of microcirculation assessments mean that they should be incorporated as part of an overall assessment of HS patients. Future research should explore how to better combine microcirculation and macrocirculation monitoring for the early identification and prognosis of HS patients.

The Effectiveness of Prehospital Subcutaneous Continuous Lactate Monitoring in Adult Trauma: A Systematic Review

INTRODUCTION

Existing diagnostics for polytrauma patients continue to rely on non-invasive monitoring techniques with limited sensitivity and specificity for critically unwell patients. Lactate is a known diagnostic and prognostic marker used in infection and trauma and has been associated with mortality, need for surgery, and organ dysfunction. Point-of-care (POC) testing allows for the periodic assessment of lactate levels; however, there is an associated expense and equipment burden associated with repeated sampling, with limited feasibility in prehospital care. Subcutaneous lactate monitoring has the potential to provide a dynamic assessment of physiological lactate levels and utilize these trends to guide management and response to given treatments.

STUDY OBJECTIVE

The aim of this study was to appraise the current literature on dynamic subcutaneous continuous lactate monitoring (SCLM) in adult trauma patients and its use in lactate-guided therapy in the prehospital environment.

METHODS

The systematic review was conducted in accordance with the PRISMA guidelines and registered with PROSPERO. Searched databases included PubMed, EMBASE via Ovid SP, Cochrane Library, and Web of Science. Databases were searched from inception to March 29, 2022. Relevant manuscripts were further scrutinized for reference citations to interrogate the fullness of the adjacent literature.

RESULTS

Searches returned 600 studies, including 551 unique manuscripts. Following title and abstract screening, 14 manuscripts met the threshold for full-text sourcing. Subsequent to the scrutiny of all 14 manuscripts, none fully met the specified eligibility criteria. Following careful examination, no article was found to cover the exact area of scientific inquiry due to disparity in technological or environmental characteristics.

CONCLUSION

Little is known about the utility of dynamic subcutaneous lactate monitoring, and this review highlights a clear gap in current literature. Novel subcutaneous lactate monitors are in development, and the literature describing the prototype experimentation has been summarized. These studies demonstrate device accuracy, which shows a close correlation with venous lactate while providing dynamic readings without significant lag times. Their availability and cost remain barriers to implementation at present. This represents a clear target for future feasibility studies to be conducted into the clinical use of dynamic subcutaneous lactate monitoring in trauma and resuscitation.

Early correction of base deficit decreases late mortality in polytrauma

INTRODUCTION

Physiology-driven resuscitation has become the standard of care in severely injured patients. This has resulted in a decrease in acute deaths by hemorrhagic shock. With increased survival from hemorrhage, focus shifts towards death later during hospital stay. This population based cohort study investigated the association of initial physiology derangement correction and (late) mortality.

METHODS

Consecutive polytrauma patients aged > 15 years with deranged physiology who were admitted to a level-1 trauma center intensive care unit (ICU) from 2015 to 2021, and requiring surgical intervention < 24 h were included. Patients who acutely (< 48 h) died were excluded. Demographics, treatment, and outcome parameters were analyzed. Physiology was monitored by serial base deficits (BD) during the first 48 h. Correction of physiology was defined as BD return to normal values. Area under the curve (AUC) of BD in time was used as measurement for the correction of physiological derangement and related to mortality 3-6 days (early), and > 7 days (late).

RESULTS

Two hundred thirty-five patients were included with a median age of 44 years (70% male), and Injury Severity Score (ISS) of 33. Mortality rate was 16% (71% due to traumatic brain injury (TBI)). Median time to death was 11 (6-17) days; 71% died > 7 days after injury. There was no difference between the single base deficit measurements in the emergency department(ED), operating room (OR), nor ICU between patients who died and those who did not. However, patients who later died were more acidotic at 24 and 48 h after arrival, and had a higher AUC of BD in time. This was independent of time and cause of death.

CONCLUSION

Early physiological restoration based on serial BD measurements in the first 48 h after injury decreases late mortality.

End-tidal carbon dioxide measured at emergency department triage outperforms standard triage vital signs in predicting in-hospital mortality and intensive care unit admission

OBJECTIVES

This study assessed the ability of end-tidal carbon dioxide (ETCO2 ) in predicting in-hospital mortality and intensive care unit (ICU) admission compared to standard vital signs at ED triage as well as comparing to measures of metabolic acidosis.

METHODS

This prospective study enrolled adult patients presenting to the ED of a tertiary care Level I trauma center over 30 months. Patients had standard vital signs measured along with exhaled ETCO2 at triage. Outcome measures included in-hospital mortality; ICU admission; and correlations with lactate, sodium bicarbonate (HCO3 ), and anion gap.

RESULTS

There were 1136 patients enrolled and 1091 patients with outcome data available. There were 26 (2.4%) patients who did not survive to hospital discharge. Mean ETCO2 levels were 34 (33-34) in survivors and 22 (18-26) nonsurvivors (p < 0.001). The area under the curve (AUC) for predicting in-hospital mortality for ETCO2 was 0.82 (0.72-0.91). In comparison the AUC for temperature was 0.55 (0.42-0.68), respiratory rate (RR) 0.59 (0.46-0.73), systolic blood pressure (SBP) 0.77 (0.67-0.86), diastolic blood pressure (DBP) 0.70 (0.59-0.81), heart rate (HR) 0.76 (0.66-0.85), and oxygen saturation (SpO2 ) 0.53 (0.40-0.67). There were 64 (6%) patients admitted to the ICU, and the ETCO2 AUC for predicting ICU admission was 0.75 (0.67-0.80). In comparison the AUC for temperature was 0.51, RR 0.56, SBP 0.64, DBP 0.63, HR 0.66, and SpO2 0.53. Correlations between expired ETCO2 and serum lactate, anion gap, and HCO3 were rho = -0.25 (p < 0.001), rho = -0.20 (p < 0.001), and rho = 0.330 (p < 0.001), respectively.

CONCLUSIONS

ETCO2 was a better predictor of in-hospital mortality and ICU admission than the standard vital signs at ED triage. ETCO2 correlated significantly with measures of metabolic acidosis.

The European guideline on management of major bleeding and coagulopathy following trauma: sixth edition

BACKGROUND

Severe trauma represents a major global public health burden and the management of post-traumatic bleeding continues to challenge healthcare systems around the world. Post-traumatic bleeding and associated traumatic coagulopathy remain leading causes of potentially preventable multiorgan failure and death if not diagnosed and managed in an appropriate and timely manner. This sixth edition of the European guideline on the management of major bleeding and coagulopathy following traumatic injury aims to advise clinicians who care for the bleeding trauma patient during the initial diagnostic and therapeutic phases of patient management.

METHODS

The pan-European, multidisciplinary Task Force for Advanced Bleeding Care in Trauma included representatives from six European professional societies and convened to assess and update the previous version of this guideline using a structured, evidence-based consensus approach. Structured literature searches covered the period since the last edition of the guideline, but considered evidence cited previously. The format of this edition has been adjusted to reflect the trend towards concise guideline documents that cite only the highest-quality studies and most relevant literature rather than attempting to provide a comprehensive literature review to accompany each recommendation.

RESULTS

This guideline comprises 39 clinical practice recommendations that follow an approximate temporal path for management of the bleeding trauma patient, with recommendations grouped behind key decision points. While approximately one-third of patients who have experienced severe trauma arrive in hospital in a coagulopathic state, a systematic diagnostic and therapeutic approach has been shown to reduce the number of preventable deaths attributable to traumatic injury.

CONCLUSION

A multidisciplinary approach and adherence to evidence-based guidelines are pillars of best practice in the management of severely injured trauma patients. Further improvement in outcomes will be achieved by optimising and standardising trauma care in line with the available evidence across Europe and beyond.

Keeping it simple: the value of mortality prediction after trauma with basic indices like the Reverse Shock Index multiplied by Glasgow Coma Scale

BACKGROUND

Identification of trauma patients at significant risk of death in the prehospital setting is challenging. The prediction probability of basic indices like vital signs, Shock Index (SI), SI multiplied by age (SIA) or the GCS is limited and more complex scores are not feasible on-scene. The Reverse SI multiplied by GCS score (rSIG) has been proposed as a triage tool to identify trauma patients with an increased risk of dying at EDs. Age adjustment (rSIG/A) displayed no advantage.We aim to (1) validate the accuracy of the rSIG in predicting death or early transfusion in a large trauma registry population, and (2) determine if the rSIG is valid for evaluation of trauma patients in the prehospital setting.

METHODS

70 829 trauma patients were retrieved from the TraumaRegister DGU database (time period between 2008 and 2017). The area under the receiver operating characteristic curve (AUROC) was calculated to measure the ability of SI, SIA, rSIG and rSIG divided by age (rSIG/A) to predict in-hospital mortality from data at the time of hospital arrival and solely from prehospital data.

RESULTS

The rSIG at time of hospital admission was not sufficiently predictive for clinical decision-making. However, rSIG calculated solely from prehospital data accurately predicted risk of death. Using prehospital data, the AUROC for mortality of rSIG/A was the highest (0.85; CI: 0.85 to 0.86), followed by rSIG (0.76; CI: 0.75 to 0.77), SIA (0.71; CI: 0.70 to 0.71) and SI (0.48; CI: 0.47 to 0.49).

CONCLUSION

The prehospital rSIG/A can be a useful adjunct for the prehospital evaluation of trauma patients and their allocation to trauma centres or trauma team activation. However, we could not confirm that the rSIG at hospital admission is a reliable tool for risk stratification.

Machine Learning Consensus Clustering Approach for Patients with Lactic Acidosis in Intensive Care Units

BACKGROUND

Lactic acidosis is a heterogeneous condition with multiple underlying causes and associated outcomes. The use of multi-dimensional patient data to subtype lactic acidosis can personalize patient care. Machine learning consensus clustering may identify lactic acidosis subgroups with unique clinical profiles and outcomes.

METHODS

We used the Medical Information Mart for Intensive Care III database to abstract electronic medical record data from patients admitted to intensive care units (ICU) in a tertiary care hospital in the United States. We included patients who developed lactic acidosis (defined as serum lactate ≥ 4 mmol/L) within 48 h of ICU admission. We performed consensus clustering analysis based on patient characteristics, comorbidities, vital signs, organ supports, and laboratory data to identify clinically distinct lactic acidosis subgroups. We calculated standardized mean differences to show key subgroup features. We compared outcomes among subgroups.

RESULTS

We identified 1919 patients with lactic acidosis. The algorithm revealed three best unique lactic acidosis subgroups based on patient variables. Cluster 1 (n = 554) was characterized by old age, elective admission to cardiac surgery ICU, vasopressor use, mechanical ventilation use, and higher pH and serum bicarbonate. Cluster 2 (n = 815) was characterized by young age, admission to trauma/surgical ICU with higher blood pressure, lower comorbidity burden, lower severity index, and less vasopressor use. Cluster 3 (n = 550) was characterized by admission to medical ICU, history of liver disease and coagulopathy, acute kidney injury, lower blood pressure, higher comorbidity burden, higher severity index, higher serum lactate, and lower pH and serum bicarbonate. Cluster 3 had the worst outcomes, while cluster 1 had the most favorable outcomes in terms of persistent lactic acidosis and mortality.

CONCLUSIONS

Consensus clustering analysis synthesized the pattern of clinical and laboratory data to reveal clinically distinct lactic acidosis subgroups with different outcomes.

Comparison of the Previous and Current Trauma-Related Shock Classifications: A Retrospective Cohort Study from a Level I Trauma Center

PURPOSE

The aim was to examine the predictive value of the hypovolemic shock classification currently accepted by the Advanced Trauma Life Support (ATLS) program over the previous one, which used only vital signs (VS) for patient allocation. The primary outcome was 30-day mortality; as secondary outcome, heart rate (HR), systolic blood pressure (SBP), Glasgow Coma Scale (GCS) and base deficit (BD) data were compared and investigated in terms of mortality prediction.

METHODS

Retrospective analysis at a level I trauma center between 2014 and 2019. Adult patients treated by trauma teams were allocated into severity classes (I-IV) based on the criteria of the current and previous ATLS classifications, respectively. The prognostic values for the classifications were determined with Fisher's exact test and χ2 test for independence, and compared with the 2-proportion Z test. The individual variables were analyzed with receiver-operating characteristic (ROC) analyses.

RESULTS

A total of 156 patients met the inclusion criteria. Mortality was effectively predicted by both classifications, and there was no statistically significant difference between the predictive performances. According to ROC analyses, GCS, BD and SBP had significant prognostic values while HR change was ineffective in this regard.

CONCLUSIONS

The currently used ATLS shock classification does not appear to be superior to the VS-based previous classification. GCS, BD and SBP are useful parameters to predict the prognosis. Changes in HR do not reflect the clinical course accurately; thus, further studies will be needed to determine the value of this parameter in trauma-associated hypovolemic-hemorrhagic shock conditions.

Uso de los gases arteriales en trauma

El trauma continúa siendo una de las primeras causas de muertes prevenibles en nuestro país. A pesar de la disminución del trauma militar, la incidencia que abarca todas las formas de trauma continúa siendo alta y congestiona los servicios de urgencias, por eso es fundamental el adecuado enfoque inicial para disminuir la mortalidad. Tradicionalmente, se han utilizado marcadores, como los signos vitales, para la identificación del choque hemorrágico, pero estudios observacionales de gran escala han demostrado cómo estos muchas veces no logran identificar a los pacientes con choque hemorrágico, haciendo necesario usar marcadores más objetivos, como los gases arteriales, con la medición del lactato y el déficit de base, que según literatura tienen mejor predicción de mortalidad, identificación temprana del choque y activación temprana de protocolos transfusionales.

Correlation of Nasal Cannula End-Tidal Carbon Dioxide Concentration With Need for Critical Resources for Blunt Trauma Patients Triaged to Lower-Tier Trauma Activation

Patients assigned lower-tier trauma activation may be undertriaged. Delayed recognition and intervention may adversely affect outcome. For critically injured intubated patients, research shows that abnormally low end-tidal carbon dioxide (EtCO2) values correlate with need for blood transfusion, surgery, and mortality. The purpose of this study was to evaluate EtCO2 monitoring for patients triaged to lower-tier trauma activation. EtCO2 monitoring may aid in the recognition of patients who have greater needs than anticipated. This is a prospective observational study conducted at a Level I trauma center. Potential subjects presenting from the field were identified by lower-tier trauma activation for blunt mechanism. EtCO2 measurements acquired using nasal cannula sidestream technology were prospectively recorded in the trauma bay during the initial assessment. The medical record and trauma registry were queried for demographics, injury data, mortality, and critical resource data defined as intubation, blood transfusion, surgery, intensive care unit admission, and vasoactive medication infusion. EtCO2 data were obtained for 682 subjects during a 10.5-month period. Following exclusions, 262 patients were enrolled for data collection. EtCO2 values less than 30 mmHg were significantly associated with blood transfusion (p = .03) but not with other critical resources or mortality. Although capnography had limited utility for patients triaged to lower-tier trauma activation, EtCO2 values less than 30 mmHg correlated with blood transfusion, consistent with previous studies of critically injured intubated patients. EtCO2 monitoring is noninvasive and may serve as a simple prompt for earlier initiation of blood transfusion, a resource-intensive intervention.

Shock index is better than conventional vital signs for assessing higher level of care and mortality in severe sepsis or shock

BACKGROUND

Conventional vital signs alone have limitations in determining the physiological status. Age-adjusted shock-index (SIPA), a comprehensive physiological variable, defined as the ratio of heart rate (HR) and systolic blood pressure (SBP) may be better at predicting hemodynamic stability and outcome than vital signs.

OBJECTIVES

To compare discriminatory power of SIPA against vital signs in assessing higher level of care (vasopressor use and mechanical ventilation) and early mortality in severe sepsis/septic shock.

METHODS

Prospective cohort study of 116children <14 years with severe sepsis/septic shock admitted at emergency department of a tertiary care hospital. Association between abnormal signs (raised heart-rate; HR, lower systolic blood-pressure; SBP, high SIPA) and higher level of care and early mortality at 0 and completed 6 hours (t0, t6) were assessed using univariate/multivariate analysis. Area-under-receiver-operating-characteristic curves (AUROC) of SIPA and conventional vital signs for outcome variables and their correlation with arterial lactate using Pearson's-coefficient were noted.

RESULTS

High SIPA was independently associated with higher level of care i.e. vasopressor use, mechanical ventilation (AUROC t0: 0.698, 0.730; AUROC t6; 0.733, 0.735) as well as early mortality (AUROC t0: 0.638; AUROC t6:0.721) at t0 and t6. At t0, only high SIPA (r² = 0.313) fairly correlated with arterial lactate (4.5 mmol/L). At t6, HR and SBP showed weak and SIPA (r² = 0.434) demonstrated moderate correlation with arterial lactate.

CONCLUSIONS

SIPA performs better than conventional vital-signs in recognising higher-level-of-care and early mortality.

Prehospital lactate improves prediction of the need for immediate interventions for hemorrhage after trauma

The blood lactate level is used to guide the management of trauma patients with circulatory disturbance. We hypothesized that blood lactate levels at the scene (Lac scene) could improve the prediction for immediate interventions for hemorrhage. We prospectively measured blood lactate levels and assessed retrospectively in 435 trauma patients both at the scene and on arrival at the emergency room (ER) of a level I trauma center. Primary outcome was immediate intervention for hemorrhage defined as surgical/radiological intervention and/or blood transfusion within 24 h. Physiological variables plus Lac scene significantly increased the predictive value for immediate intervention (area under the curve [AUC] 0.882, 95% confidence interval [CI] 0.839-0.925) compared to that using physiological variables only (AUC 0.837, 95% CI 0.787-0.887, P = 0.0073), replicated in the validation cohort (n = 85). There was no significant improvement in predicting value of physiological variables plus Lac scene for massive transfusion compared to physiological variables (AUC 0.903 vs 0.895, P = 0.32). The increased blood lactate level per minute from scene to ER was associated with increased probability for immediate intervention (P < 0.0001). Both adding Lac scene to physiological variables and the temporal elevation of blood lactate levels from scene to ER could improve the prediction of the immediate intervention.

The European guideline on management of major bleeding and coagulopathy following trauma: fifth edition

Background

Severe traumatic injury continues to present challenges to healthcare systems around the world, and post-traumatic bleeding remains a leading cause of potentially preventable death among injured patients. Now in its fifth edition, this document aims to provide guidance on the management of major bleeding and coagulopathy following traumatic injury and encourages adaptation of the guiding principles described here to individual institutional circumstances and resources.

Methods

The pan-European, multidisciplinary Task Force for Advanced Bleeding Care in Trauma was founded in 2004, and the current author group included representatives of six relevant European professional societies. The group applied a structured, evidence-based consensus approach to address scientific queries that served as the basis for each recommendation and supporting rationale. Expert opinion and current clinical practice were also considered, particularly in areas in which randomised clinical trials have not or cannot be performed. Existing recommendations were re-examined and revised based on scientific evidence that has emerged since the previous edition and observed shifts in clinical practice. New recommendations were formulated to reflect current clinical concerns and areas in which new research data have been generated.

Results

Advances in our understanding of the pathophysiology of post-traumatic coagulopathy have supported improved management strategies, including evidence that early, individualised goal-directed treatment improves the outcome of severely injured patients. The overall organisation of the current guideline has been designed to reflect the clinical decision-making process along the patient pathway in an approximate temporal sequence. Recommendations are grouped behind the rationale for key decision points, which are patient- or problem-oriented rather than related to specific treatment modalities. While these recommendations provide guidance for the diagnosis and treatment of major bleeding and coagulopathy, emerging evidence supports the author group’s belief that the greatest outcome improvement can be achieved through education and the establishment of and adherence to local clinical management algorithms.

Conclusions

A multidisciplinary approach and adherence to evidence-based guidance are key to improving patient outcomes. If incorporated into local practice, these clinical practice guidelines have the potential to ensure a uniform standard of care across Europe and beyond and better outcomes for the severely bleeding trauma patient.

Electronic supplementary material

The online version of this article (10.1186/s13054-019-2347-3) contains supplementary material, which is available to authorized users.

A retrospective analysis of the respiratory adjusted shock index to determine the presence of occult shock in trauma patients

BACKGROUND

The shock index (SI), calculated as hear rate/systolic blood pressure, is a simple hemodynamic marker that may be used to assess for the presence of occult shock in trauma patients. The normal range for a healthy adult patient is 0.5 to 0.7. Recently, studies have demonstrated that tachypnea is the most important predictor of cardiac arrest in hospital wards and is an important indicator of derangements across multiple organ systems. As such, we have sought to determine whether the inclusion of the patient's respiratory rate (RR) to the already existing SI (called the Respiratory Adjusted Shock Index [RASI]), calculated as hear rate/systolic blood pressure*(RR/10), will improve the overall diagnostic accuracy of detecting patients in early occult shock.

METHODS

A retrospective chart review over a 4-year period (2012-2016) at an urban, Level I trauma center was performed. All patients admitted to hospital for trauma were included in the study. Exclusion criteria were patients in traumatic arrest or in overt shock. Charts were reviewed for triage vital signs and point of care lactate drawn within 30 minutes of presentation. A lactate greater than 2 mmol/L was used to determine presence of hypoperfusion. The upper limit of normal for the RASI was calculated by multiplying the upper limit of the SI by 1.9 (RR of 19 divided by 10) and validated internally.

RESULTS

A total of 3,093 patients were included in this study. There was no difference in SI for patients discharged versus patients admitted, 0.6 (95% CI, 0.5-0.7) versus 0.7 (95% CI, 0.5-0.8) and a significant difference between the same groups of patients (discharged vs. admitted) for the RASI, 1.1 (95% CI, 1.04-1.18) versus 1.46 (95% CI, 1.35-1.55), respectively. Area under the curve for SI was 0.58 and for the RASI score was 0.94.

CONCLUSION

The RASI score improves diagnostic accuracy for detecting early occult shock in trauma patients when compared to the SI.

LEVEL OF EVIDENCE

Diagnostic, level II.

Respiratory adjusted shock index for identifying occult shock and level of Care in Sepsis Patients

OBJECTIVE

Early identification of shock allows for timely resuscitation. Previous studies note the utility of bedside calculations such as the shock index (SI) and quick sepsis-related organ failure assessment (qSOFA) to detect occult shock. Respiratory rate may also be an important marker of occult shock. The goal of our study was to evaluate whether using a modified SI with respiratory rate would improve identification of emergency department sepsis patients admitted to an ICU or stepdown unit.

METHODS

A prospective, observational cohort study of the respiratory adjusted shock index (RASI), defined as HR/SBP × RR/10, was conducted. RASI was calculated from triage vital signs and compared to serum lactate. Primary outcome was admission to a higher level of care defined as ICU or stepdown unit. A multivariable logistic regression model including RASI, SI, lactate, age and sex was performed with disposition as the outcome variable. Areas under the curve (AUC) were calculated to detect occult shock and level of care for RASI, SI, and qSOFA.

RESULTS

408 patients were enrolled, 360 were included in the analysis. Regression analysis revealed that lactate (OR 1.55, z = 4.38, p < 0.0001) and RASI (OR 2.27, z = 3.03, p < 0.002) were predictive of need for higher level of care. The AUC for RASI, SI, and qSOFA to detect occult shock were 0.71, 0.6, and 0.61 respectively. RASI also had a significant AUC in predicting level of care at 0.75 compared to SI (0.64) and qSOFA (0.62).

CONCLUSIONS

RASI may have utility as a rapid bedside tool for predicting critical illness in sepsis patients.

A comparison of base deficit and vital signs in the early assessment of patients with penetrating trauma in a high burden setting

INTRODUCTION

An assessment of physiological status is a key step in the early assessment of trauma patients with implications for triage, investigation and management. This has traditionally been done using vital signs. Previous work from large European trauma datasets has suggested that base deficit (BD) predicts clinically important outcomes better than vital signs (VS). A BD derived classification of haemorrhagic shock appeared superior to one based on VS derived from ATLS criteria in a population of predominantly blunt trauma patients. The initial aim of this study was to see if this observation would be reproduced in penetrating trauma patients. The power of each individual variable (BD, heart rate (HR), systolic blood pressure (SBP), shock index(SI) (HR/SBP) and Glasgow Coma Score (GCS)) to predict mortality was then also compared.

METHODS

A retrospective analysis of adult trauma patients presenting to the Pietermaritzburg Metropolitan Trauma Service was performed. Patients were classified into four "shock" groups using VS or BD and the outcomes compared. Receiver Operator Characteristic (ROC) curves were then generated to compare the predictive power for mortality of each individual variable.

RESULTS

1863 patients were identified. The overall mortality rate was 2.1%. When classified by BD, HR rose and SBP fell as the "shock class" increased but not to the degree suggested by the ATLS classification. The BD classification of haemorrhagic shock appeared to predict mortality better than that based on the ATLS criteria. Mortality increased from 0.2% (Class 1) to 19.7% (Class 4) based on the 4 level BD classification. Mortality increased from 0.3% (Class 1) to 12.6% (Class 4) when classified based by VS. Area under the receiver operator characteristic (AUROC) curve analysis of the individual variables demonstrated that BD predicted mortality significantly better than HR, GCS, SBP and SI. AUROC curve (95% Confidence Interval (CI)) for BD was 0.90 (0.85-0.95) compared to HR 0.67(0.56-0.77), GCS 0.70(0.62-0.79), SBP 0.75(0.65-0.85) and SI 0.77(0.68-0.86).

CONCLUSION

BD appears superior to vital signs in the immediate physiological assessment of penetrating trauma patients. The use of BD to assess physiological status may help refine their early triage, investigation and management.

Lactate as predictor of mortality in polytrauma

BACKGROUND

The lactate is a product of anaerobic metabolism; it can be used as a marker on demand and availability of oxygen. Changes in lactate levels can be effectively used as a marker in resuscitation maneuvers, even in patients with stable vital signs.

AIM

To verify the lactate clearance as a predictor of mortality in trauma patients, in need of intensive care.

METHOD

A total of 851 patients were admitted in ICU, in which 146 were victims of multiple trauma; due to the exclusion criteria, were included 117.

RESULTS

Patients were 87% male, mean age 32.4 years, motorcycle drivers, Glasgow coma scale between 3-8, affected by cranial trauma, followed by abdominal trauma. Was verified mortality up to 48 h and global mortality, that did not show statistical relationship between lactate clearance and mortality (p=0.928).

CONCLUSION

There is no correlation between admission lactate or lactate clearance and mortality in patients treated with multiple trauma.

The European guideline on management of major bleeding and coagulopathy following trauma: fourth edition

BACKGROUND

Severe trauma continues to represent a global public health issue and mortality and morbidity in trauma patients remains substantial. A number of initiatives have aimed to provide guidance on the management of trauma patients. This document focuses on the management of major bleeding and coagulopathy following trauma and encourages adaptation of the guiding principles to each local situation and implementation within each institution.

METHODS

The pan-European, multidisciplinary Task Force for Advanced Bleeding Care in Trauma was founded in 2004 and included representatives of six relevant European professional societies. The group used a structured, evidence-based consensus approach to address scientific queries that served as the basis for each recommendation and supporting rationale. Expert opinion and current clinical practice were also considered, particularly in areas in which randomised clinical trials have not or cannot be performed. Existing recommendations were reconsidered and revised based on new scientific evidence and observed shifts in clinical practice; new recommendations were formulated to reflect current clinical concerns and areas in which new research data have been generated. This guideline represents the fourth edition of a document first published in 2007 and updated in 2010 and 2013.

RESULTS

The guideline now recommends that patients be transferred directly to an appropriate trauma treatment centre and encourages use of a restricted volume replacement strategy during initial resuscitation. Best-practice use of blood products during further resuscitation continues to evolve and should be guided by a goal-directed strategy. The identification and management of patients pre-treated with anticoagulant agents continues to pose a real challenge, despite accumulating experience and awareness. The present guideline should be viewed as an educational aid to improve and standardise the care of the bleeding trauma patients across Europe and beyond. This document may also serve as a basis for local implementation. Furthermore, local quality and safety management systems need to be established to specifically assess key measures of bleeding control and outcome.

CONCLUSIONS

A multidisciplinary approach and adherence to evidence-based guidance are key to improving patient outcomes. The implementation of locally adapted treatment algorithms should strive to achieve measureable improvements in patient outcome.

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.

The Shock Index revisited - a fast guide to transfusion requirement? A retrospective analysis on 21,853 patients derived from the TraumaRegister DGU

INTRODUCTION

Isolated vital signs (for example, heart rate or systolic blood pressure) have been shown unreliable in the assessment of hypovolemic shock. In contrast, the Shock Index (SI), defined by the ratio of heart rate to systolic blood pressure, has been advocated to better risk-stratify patients for increased transfusion requirements and early mortality. Recently, our group has developed a novel and clinical reliable classification of hypovolemic shock based upon four classes of worsening base deficit (BD). The objective of this study was to correlate this classification to corresponding strata of SI for the rapid assessment of trauma patients in the absence of laboratory parameters.

METHODS

Between 2002 and 2011, data for 21,853 adult trauma patients were retrieved from the TraumaRegister DGU database and divided into four strata of worsening SI at emergency department arrival (group I, SI <0.6; group II, SI ≥0.6 to <1.0; group III, SI ≥1.0 to <1.4; and group IV, SI ≥1.4) and were assessed for demographics, injury characteristics, transfusion requirements, fluid resuscitation and outcomes. The four strata of worsening SI were compared with our recently suggested BD-based classification of hypovolemic shock.

RESULTS

Worsening of SI was associated with increasing injury severity scores from 19.3 (± 12) in group I to 37.3 (± 16.8) in group IV, while mortality increased from 10.9% to 39.8%. Increments in SI paralleled increasing fluid resuscitation, vasopressor use and decreasing hemoglobin, platelet counts and Quick's values. The number of blood units transfused increased from 1.0 (± 4.8) in group I to 21.4 (± 26.2) in group IV patients. Of patients, 31% in group III and 57% in group IV required ≥10 blood units until ICU admission. The four strata of SI discriminated transfusion requirements and massive transfusion rates equally with our recently introduced BD-based classification of hypovolemic shock.

CONCLUSION

SI upon emergency department arrival may be considered a clinical indicator of hypovolemic shock in respect to transfusion requirements, hemostatic resuscitation and mortality. The four SI groups have been shown to equal our recently suggested BD-based classification. In daily clinical practice, SI may be used to assess the presence of hypovolemic shock if point-of-care testing technology is not available.

Recognition of hypovolemic shock: using base deficit to think outside of the ATLS box

Base deficit has frequently been utilized as an informal adjunct in the initial evaluation of trauma patients to assess the extent of their physiologic derangements. However, the current Advanced Trauma Life Support (ATLS) classification system for hypovolemic shock does not include base-deficit measurements and relies primarily on alterations in vital signs (heart rate, systolic blood pressure) and mental status (Glasgow Coma Scale) to estimate blood loss. The authors of this paper propose that the current ATLS system may not accurately reflect the degree of hypovolemic shock in many patients and that base-deficit measurements should be used in its place. The proposed system showed a greater correlation with transfusion requirements, need for massive transfusion, and mortality when compared with the ATLS classification system. Based on these findings, base-deficit measurement should be strongly considered during the initial trauma evaluation to identify the presence of hypovolemic shock and to guide blood product administration.