Shock index as a marker for significant injury in trauma patients

Establishing thresholds for shock index in children to identify major trauma

BACKGROUND

An abnormal shock index (SI) is associated with greater injury severity among children with trauma. We sought to empirically-derive age-adjusted SI cutpoints associated with major trauma in children, and to compare the accuracy of these cutpoints to existing criteria for pediatric SI.

METHODS

We performed a retrospective cohort study using the 2021 National Trauma Data Bank (NTDB) Participant Use File. We included injured children (<18 years), excluding patients with traumatic arrests, mechanical ventilation upon hospital presentation, and inter-facility transfers. Our outcome was major trauma defined by the standardized triage assessment tool (STAT) criteria. Our exposure of interest was the SI. We empirically-derived upper and lower cutpoints for the SI using age-adjusted Z-scores. We compared the performance of these to the SI, pediatric-adjusted (SIPA), and the Pediatric SI (PSI). We validated the performance of the cutpoints in the 2019 NTDB.

RESULTS

We included 64,326 and 64,316 children in the derivation and validation samples, of whom 4.9 % (derivation) and 4.0 % (validation) experienced major trauma. The empirically-derived age-adjusted SI cutpoints had a sensitivity of 43.2 % and a specificity of 79.4 % for major trauma in the validation sample. The sensitivity of the PSI for major trauma was 33.9 %, with a specificity of 90.7 % among children 1-17 years of age. The sensitivity of the SIPA was 37.4 %, with a specificity of 87.8 % among children 4-16 years of age. Evaluated using logistic regression, patients with an elevated age-adjusted SI had 3.97 greater odds (95 % confidence interval [CI] 3.63-4.33) of major trauma compared to those with a normal age-adjusted SI. Patients with a depressed SI had 1.55 greater odds (95 % CI 1.36-1.78) of major trauma. The area under the receiver operator characteristic curve (AUROC) for the empirically-derived model (0.62, 95 % CI 0.61-0.63) was similar to the AUROC for PSI (0.62, 95 % CI 0.61-0.63); both of which were greater than the SIPA model (0.58, 95 % CI 0.57-0.59).

CONCLUSION

Age-adjusted SI cutpoints demonstrated a mild gain in sensitivity compared to existing measures. However, our findings suggest that the SI alone has a limited role in the identification of major trauma in children.

Use of Shock Index, Modified Shock Index, and Age-Adjusted Shock Index for Detection of Postpartum Hemorrhage

PURPOSE

The aim of this study is to evaluate the role of shock index (SI), modified shock index (MSI), and delta shock index (ΔSI) in predicting postpartum hemorrhage (PPH) and adverse maternal outcomes.

MATERIAL AND METHODS

In this cross-sectional cohort study, a study group consisting of 416 pregnant women who delivered at our hospital and had postpartum hemorrhage was compared with 467 control patients with normal follow-up. SI (pulse/systolic blood pressure), MSI (pulse/mean arterial pressure), ΔSI (input SI - 2nd- or 6th-hour SI) values were calculated.

RESULTS

A total of 883 postpartum women were included in the study. The study group had higher peripartum, 2nd-hour, and 6th-hour SI values (p=0.011, p=0.001, p<0.001, respectively). Peripartum MSI values (p=0.004), 2nd-hour MSI values (p<0.001), and 6th-hour MSI values (p<0.001) were significantly lower in the control group than in the PPH group. When the groups were evaluated, the cut-off value of the 2nd-hour SI parameter was>0.8909 (sensitivity 30%, specificity 84%), and the 6th-hour SI parameter was>0.8909 (sensitivity 40%, specificity 80%) for predicting postpartum hemorrhage requiring blood transfusion and surgical intervention. The cut-off value of the 2nd-hour MSI parameter was>1.2 (sensitivity 34%, specificity 82%), and the cut-off value of the 6th-hour MSI parameter was>1.2652 (sensitivity 32%, specificity 90%).

CONCLUSION

The 2nd- and 6th-hour SI and 2nd- and 6th-hour MSI values were significantly higher in patients with postpartum hemorrhage. Values greater than 0.89 for SI and 1.2 for MSI were considered significant for predicting postpartum hemorrhage with maternal impairment.

An Assessment of Clinical Accuracy of Vital Sign-based Triage Tools Among U.S. and Coalition Forces

INTRODUCTION

Early appropriate allocation of resources for critically injured combat casualties is essential. This is especially important when inundated with an overwhelming number of casualties where limited resources must be efficiently allocated, such as during mass casualty events. There are multiple scoring systems utilized in the prehospital combat setting, including the shock index (SI), modified shock index (MSI), simple triage and rapid treatment (START), revised trauma score (RTS), new trauma score (NTS), Glasgow Coma Scale + age + pressure (GAP), and the mechanism + GAP (MGAP) score. The optimal score for application to the combat trauma population remains unclear.

MATERIALS AND METHODS

This is a secondary analysis of a previously described dataset from the Department of Defense Trauma Registry from January 1, 2007 through March 17, 2020. We constructed univariable analyses to determine the area under the receiving operator characteristic (AUROC) for the scoring systems of interest. Our primary outcomes were early death (within 24 hours) or early massive transfusion, as defined by ≥3 units.

RESULTS

There were 12,268 casualties that met inclusion criteria. There were 168 (1%) who died within the first 24 hours and 2082 (17%) that underwent significant transfusion within the first 24 hours. When assessing the predictive capabilities for death within 24 hours, the AUROCs were 0.72 (SI), 0.69 (MSI), 0.89 (START), 0.90 (RTS), 0.83 (NTS), 0.90 (GAP), and 0.91 (MGAP). The AUROCs for massive transfusion were 0.89 (SI), 0.89 (MSI), 0.82 (START), 0.81 (RTS), 0.83 (NTS), 0.85 (MGAP), and 0.86 (GAP).

CONCLUSIONS

This study retrospectively applied seven triage tools to a database of 12,268 cases from the Department of Defense Trauma Registry to evaluate their performance in predicting early death or massive transfusion in combat. All scoring systems performed well with an AUROC >0.8 for both outcomes. Although the SI and MSI performed best for predicting massive transfusion (both had an AUROC of 0.89), they ranked last for assessment of mortality within 24 hours, with the other tools performing well. START, RTS, NTS, MGAP and GAP reliably identified early death and need for massive transfusion, with MGAP and GAP performing the best overall. These findings highlight the importance of assessing triage tools to best manage resources and ultimately preserve lives of traumatically wounded warfighters. Further studies are needed to explain the surprising performance discrepancy of the SI and MSI in predicting early death and massive transfusion.

Centiles for the shock index among injured children in the prehospital setting

OBJECTIVE

The shock index (SI), the ratio of heart rate to systolic blood pressure, is a clinical tool for assessing injury severity. Age-adjusted SI models may improve predictive value for injured children in the out-of-hospital setting. We sought to characterize the proportion of children in the prehospital setting with an abnormal SI using established criteria, describe the age-based distribution of SI among injured children, and determine prehospital interventions by SI.

METHODS

We performed a multi-agency retrospective cross-sectional study of children (<18 years) in the prehospital setting with a scene encounter for suspected trauma and transported to the hospital between 2018 and 2022 using the National Emergency Medical Services (EMS) Information System datasets. Our exposure of interest was the first calculated SI. We identified the proportion of children with an abnormal SI when using the SI, pediatric age-adjusted (SIPA); and the pediatric SI (PSI) criteria. We developed and internally validated an age-based distributional model for the SI using generalized additive models for location, scale, and shape to describe the age-based distribution of the SI as a centile or Z-score. We evaluated EMS interventions (basic airway interventions, advanced airway interventions, cardiac interventions, vascular access, intravenous fluids, and vasopressor use) in relation to both the SIPA, PSI, and distributional SI values.

RESULTS

We analyzed 1,007,863 pediatric EMS trauma encounters (55.0% male, median age 13 years [IQR, 8-16 years]). The most common dispatch complaint was for traffic/transport related injury (32.9%). When using the PSI and SIPA, 13.1% and 16.3% were classified as having an abnormal SI, respectively. There were broad differences in the percentage of encounters classified as having an abnormal SI across the age range, varying from 5.1 to 22.8% for SIPA and 3.7-20.1% for PSI. The SIPA values ranged from the 75th to 95th centiles, while the PSI corresponded to an SI greater than the 90th centile, except in older children. The centile distribution for SI declined during early childhood and stabilized during adolescence and demonstrated a difference of <0.1% at cutoff values. An abnormal PSI, SIPA and higher SI centiles (>90th centile and >95th centiles) were associated with interventions related to basic and advanced airway management, cardiac procedures, vascular access, and provision of intravenous fluids occurred with greater frequency at higher SI centiles. Some procedures, including airway management and vascular access, had a smaller peak at lower (<10th) centiles.

DISCUSSION

We describe the empiric distribution of the pediatric SI across the age range, which may overcome limitations of extant criteria in identifying patients with shock in the prehospital setting. Both high and low SI values were associated with important, potentially lifesaving EMS interventions. Future work may allow for more precise identification of children with significant injury using cutpoint analysis paired to outcome-based criteria. These may additionally be combined with other physiologic and mechanistic criteria to assist in triage decisions.

Diastolic/systolic blood pressure ratio for predicting febrile children with sepsis and progress to septic shock in the emergency department

OBJECTIVE

Given the scarcity of studies analyzing the clinical predictors of pediatric septic cases that would progress to septic shock, this study aimed to determine strong predictors for pediatric emergency department (PED) patients with sepsis at risk for septic shock and mortality.

METHODS

We conducted chart reviews of patients with ≥ 2 age-adjusted quick Sequential Organ Failure Assessment score (qSOFA) criteria to recognize patients with an infectious disease in two tertiary PEDs between January 1, 2021, and April 30, 2022. The age range of included patients was 1 month to 18 years. The primary outcome was development of septic shock within 48 h of PED attendance. The secondary outcome was sepsis-related 28-day mortality. Initial important variables in the PED and hemodynamics with the highest and lowest values during the first 24 h of admission were also analyzed.

RESULTS

Overall, 417 patients were admitted because of sepsis and met the eligibility criteria for the study. Forty-nine cases progressed to septic shock within 48 h after admission and 368 were discharged without progression. General demographics, laboratory data, and hemodynamics were analyzed by multivariate analysis. Only the minimum diastolic blood pressure/systolic blood pressure ratio (D/S ratio) during the first 24 h after admission remained as an independent predictor of progression to septic shock and 28-day mortality. The best cutoff values of the D/S ratio for predicting septic shock and 28-day mortality were 0.52 and 0.47, respectively.

CONCLUSIONS

The D/S ratio is a practical bedside scoring system in the PED and had good discriminative ability in predicting the progression of septic shock and in-hospital mortality in PED patients. Further validation is essential in other settings.

Shock indices are associated with in-hospital mortality among patients with septic shock and normal left ventricular ejection fraction

BACKGROUND

The understanding of shock indices in patients with septic shock is limited, and their values may vary depending on cardiac function.

METHODS

This prospective cohort study was conducted across 20 university-affiliated hospitals (21 intensive care units [ICUs]). Adult patients (≥19 years) with septic shock admitted to the ICUs during a 29-month period were included. The shock index (SI), diastolic shock index (DSI), modified shock index (MSI), and age shock index (Age-SI) were calculated at sepsis recognition (time zero) and ICU admission. Left ventricular (LV) function was categorized as either normal LV ejection fraction (LVEF ≥ 50%) or decreased LVEF (<50%).

RESULTS

Among the 1,194 patients with septic shock, 392 (32.8%) who underwent echocardiography within 24 h of time zero were included in the final analysis (normal LVEF: n = 246; decreased LVEF: n = 146). In patients with normal LVEF, only survivors demonstrated significant improvement in SI, DSI, MSI, and Age-SI values from time zero to ICU admission; however, no notable improvements were found in all patients with decreased LVEF. The completion of vasopressor or fluid bundle components was significantly associated with improved indices in patients with normal LVEF, but not in those with decreased LVEF. In multivariable analysis, each of the four indices at ICU admission was significantly associated with in-hospital mortality (P < 0.05) among patients with normal LVEF; however, discrimination power was better in the indices for patients with lower lactate levels (≤ 4.0 mmol/L), compared to those with higher lactate levels.

CONCLUSIONS

The SI, DSI, MSI, and Age-SI at ICU admission were significantly associated with in-hospital mortality in patients with septic shock and normal LVEF, which was not found in those with decreased LVEF. Our study emphasizes the importance of interpreting shock indices in the context of LV function in septic shock.

Shock index and its variants as predictors of mortality in severe traumatic brain injury

BACKGROUND

The increase in severe traumatic brain injury (sTBI) incidence is a worldwide phenomenon, resulting in a heavy disease burden in the public health systems, specifically in emerging countries. The shock index (SI) is a physiological parameter that indicates cardiovascular status and has been used as a tool to assess the presence and severity of shock, which is increased in sTBI. Considering the high mortality of sTBI, scrutinizing the predictive potential of SI and its variants is vital.

AIM

To describe the predictive potential of SI and its variants in sTBI.

METHODS

This study included 71 patients (61 men and 10 women) divided into two groups: Survival (S; n = 49) and Non-survival (NS; n = 22). The responses of blood pressure and heart rate (HR) were collected at admission and 48 h after admission. The SI, reverse SI (rSI), rSI multiplied by the Glasgow Coma Score (rSIG), and Age multiplied SI (AgeSI) were calculated. Group comparisons included Shapiro-Wilk tests, and independent samples t-tests. For predictive analysis, logistic regression, receiver operator curves (ROC) curves, and area under the curve (AUC) measurements were performed.

RESULTS

No significant differences between groups were identified for SI, rSI, or rSIG. The AgeSI was significantly higher in NS patients at 48 h following admission (S: 26.32 ± 14.2, and NS: 37.27 ± 17.8; P = 0.016). Both the logistic regression and the AUC following ROC curve analysis showed that only AgeSI at 48 h was capable of predicting sTBI outcomes.

CONCLUSION

Although an altered balance between HR and blood pressure can provide insights into the adequacy of oxygen delivery to tissues and the overall cardiac function, only the AgeSI was a viable outcome-predictive tool in sTBI, warranting future research in different cohorts.

Impact of Intra-Operative Shock and Resuscitation on Surgical Site Infections After Trauma Laparotomy

Background: Patients undergoing trauma laparotomy experience high rates of surgical site infection (SSI). Although intra-operative shock is a likely contributor to SSI risk, little is known about the relation between shock, intra-operative restoration of physiologic normalcy, and SSI development. Patients and Methods: A retrospective review of trauma patients who underwent emergent definitive laparotomy was performed. Using shock index and base excess at the beginning and end of laparotomy, patients were classified as normal, persistent shock, resuscitated, or new shock. Univariable and multivariable analyses were performed to identify predictors of organ/space SSI, superficial/deep SSI, and any SSI. Results: Of 1,191 included patients, 600 (50%) were categorized as no shock, 248 (21%) as resuscitated, 109 (9%) as new shock, and 236 (20%) as persistent shock, with incidence of any SSI as 51 (9%), 28 (11%), 26 (24%), and 32 (14%), respectively. These rates were similar in organ/space and superficial/deep SSIs. On multivariable analysis, resuscitated, new shock, and persistent shock were associated with increased odds of organ/space SSI (odds ratio [OR], 2.2; 95% confidence interval [CI], 1.3-3.5; p < 0.001) and any SSI (OR, 2.0; 95% CI, 1.4-3.2; p < 0.001), but no increased risk of superficial/deep SSI (OR, 1.4; 95% CI, 0.8-2.6; p = 0.331). Conclusions: Although the trajectory of physiologic status influenced SSI, the presence of shock at any time during trauma laparotomy, regardless of restoration of physiologic normalcy, was associated with increased odds of SSI. Further investigation is warranted to determine the relation between peri-operative shock and SSI in trauma patients.

A Novel Continuous Real-Time Vital Signs Viewer for Intensive Care Units: Design and Evaluation Study

BACKGROUND

Clinicians working in intensive care units (ICUs) are immersed in a cacophony of alarms and a relentless onslaught of data. Within this frenetic environment, clinicians make high-stakes decisions using many data sources and are often oversaturated with information of varying quality. Traditional bedside monitors only depict static vital signs data, and these data are not easily viewable remotely. Clinicians must rely on separate nursing charts-handwritten or electric-to review physiological patterns, including signs of potential clinical deterioration. An automated physiological data viewer has been developed to provide at-a-glance summaries and to assist with prioritizing care for multiple patients who are critically ill.

OBJECTIVE

This study aims to evaluate a novel vital signs viewer system in a level 1 trauma center by subjectively assessing the viewer's utility in a high-volume ICU setting.

METHODS

ICU attendings were surveyed during morning rounds. Physicians were asked to conduct rounds normally, using data reported from nurse charts and briefs from fellows to inform their clinical decisions. After the physician finished their assessment and plan for the patient, they were asked to complete a questionnaire. Following completion of the questionnaire, the viewer was presented to ICU physicians on a tablet personal computer that displayed the patient's physiologic data (ie, shock index, blood pressure, heart rate, temperature, respiratory rate, and pulse oximetry), summarized for up to 72 hours. After examining the viewer, ICU physicians completed a postview questionnaire. In both questionnaires, the physicians were asked questions regarding the patient's stability, status, and need for a higher or lower level of care. A hierarchical clustering analysis was used to group participating ICU physicians and assess their general reception of the viewer.

RESULTS

A total of 908 anonymous surveys were collected from 28 ICU physicians from February 2015 to June 2017. Regarding physicians' perception of whether the viewer enhanced the ability to assess multiple patients in the ICU, 5% (45/908) strongly agreed, 56.6% (514/908) agreed, 35.3% (321/908) were neutral, 2.9% (26/908) disagreed, and 0.2% (2/908) strongly disagreed.

CONCLUSIONS

Morning rounds in a trauma center ICU are conducted in a busy environment with many data sources. This study demonstrates that organized physiologic data and visual assessment can improve situation awareness, assist clinicians with recognizing changes in patient status, and prioritize care.

Emergency Department Shock Index Outperforms Prehospital and Delta Shock Indices in Predicting Outcomes of Trauma Patients

INTRODUCTION

Multiple shock indices (SIs), including prehospital, emergency department (ED), and delta (ED SI - Prehospital SI) have been developed to predict outcomes among trauma patients. This study aims to compare the predictive abilities of these SIs for outcomes of polytrauma patients on a national level.

METHODS

This was a retrospective analysis of the American College of Surgeons Trauma Quality Improvement Program (2017-2018). We included adult (≥18 y) trauma patients and excluded patients who were transferred, had missing vital signs, and those with severe head injuries (Head-Abbreviated Injury Scale>3). Outcome measures were 24-h and in-hospital mortality, 24-h packed red blood cells transfusions, and intensive care unit and hospital length of stay. Predictive performances of these SIs were evaluated by the Area Under the Receiver Operating Characteristics for the entire study cohort and across all injury severities.

RESULTS

A total of 750,407 patients were identified. Meanstandard deviation age and lowest systolic blood pressure were 53 ± 21 y, and 81 ± 32 mmHg, respectively. Overall, 24-h and in-hospital mortality were 1.2% and 2.5%, respectively. On multivariable analysis, all three SIs were independently associated with higher rates of 24-h and in-hospital mortality, blood product requirements, intensive care unit and hospital length of stay (P < 0.001). ED SI was superior to prehospital and delta SIs (P < 0.001) for all outcomes. On subanalysis of patients with moderate injuries, severe injuries, and positive delta SI, the results remained the same.

CONCLUSIONS

ED SI outperformed both prehospital and delta SIs across all injury severities. Trauma triage guidelines should prioritize ED SI in the risk stratification of trauma patients who may benefit from earlier and more intense trauma activations.

THE COMPENSATORY RESERVE INDEX FOR PREDICTING HEMORRHAGIC SHOCK IN PREHOSPITAL TRAUMA

ABSTRACT

Background: The compensatory reserve index (CRI) is a noninvasive, continuous measure designed to detect intravascular volume loss. CRI is derived from the pulse oximetry waveform and reflects the proportion of physiologic reserve remaining before clinical hemodynamic decompensation. Methods: In this prospective, observational, prehospital cohort study, we measured CRI in injured patients transported by emergency medical services (EMS) to a single Level I trauma center. We determined whether the rolling average of CRI values over 60 s (CRI trend [CRI-T]) predicts in-hospital diagnosis of hemorrhagic shock, defined as blood product administration in the prehospital setting or within 4 h of hospital arrival. We hypothesized that lower CRI-T values would be associated with an increased likelihood of hemorrhagic shock and better predict hemorrhagic shock than prehospital vital signs. Results: Prehospital CRI was collected on 696 adult trauma patients, 21% of whom met our definition of hemorrhagic shock. The minimum CRI-T was 0.14 (interquartile range [IQR], 0.08-0.31) in those with hemorrhagic shock and 0.31 (IQR 0.15-0.50) in those without ( P = <0.0001). The positive likelihood ratio of a CRI-T value <0.2 predicting hemorrhagic shock was 1.85 (95% confidence interval [CI], 1.55-2.22). The area under the ROC curve (AUC) for the minimum CRI-T predicting hemorrhagic shock was 0.65 (95% CI, 0.60-0.70), which outperformed initial prehospital HR (0.56; 95% CI, 0.50-0.62) but underperformed EMS systolic blood pressure and shock index (0.74; 95% CI, 0.70-0.79 and 0.72; 95% CI, 0.67-0.77, respectively). Conclusions: Low prehospital CRI-T predicts blood product transfusion by EMS or within 4 hours of hospital arrival but is less prognostic than EMS blood pressure or shock index. The evaluated version of CRI may be useful in an austere setting at identifying injured patients that require the most significant medical resources. CRI may be improved with noise filtering to attenuate the effects of vibration and patient movement.

Preoperative shock index in major abdominal emergency surgery

Introduction

Major abdominal emergency surgery (MAES) patients have a high risk of mortality and complications. The time-sensitive nature of MAES necessitates an easily calculable risk-scoring tool. Shock index (SI) is obtained by dividing heart rate (HR) by systolic blood pressure (SBP) and provides insight into a patient's haemodynamic status. We aimed to evaluate SI's usefulness in predicting postoperative mortality, acute kidney injury (AKI), requirements for intensive care unit (ICU) and high-dependency monitoring, and the ICU length of stay (LOS).

Method

We retrospectively reviewed 212,089 MAES patients from January 2013 to December 2020. The cohort was propensity matched, and 3960 patients were included. The first HR and SBP recorded in the anaesthesia chart were used to calculate SI. Regression models were used to investigate the association between SI and outcomes. The relationship between SI and survival was explored with Kaplan-Meier curves.

Results

There were significant associations between SI and mortality at 1 month (odds ratio [OR] 2.40 [1.67-3.39], P<0.001), 3 months (OR 2.13 [1.56-2.88], P<0.001), and at 2 years (OR 1.77 [1.38-2.25], P<0.001). Multivariate analysis revealed significant relationships between SI and mortality at 1 month (OR 3.51 [1.20-10.3], P=0.021) and at 3 months (OR 3.05 [1.07-8.54], P=0.034). Univariate and multivariate analysis also revealed significant relationships between SI and AKI (P<0.001), postoperative ICU admission (P<0.005) and ICU LOS (P<0.001). SI does not significantly affect 2-year mortality.

Conclusion

SI is useful in predicting postopera-tive mortality at 1 month, 3 months, AKI, postoperative ICU admission and ICU LOS.

Prehospital shock index predicts 24-h mortality in trauma patients with a normal shock index upon emergency department arrival

BACKGROUND

The shock index (heart rate divided by systolic blood pressure) of trauma patients upon emergency department arrival predicts blood loss and death. However, some patients with normal shock indices (0.4 < shock index <0.9) upon emergency department arrival also have poor prognoses. This study aimed to determine whether abnormal prehospital shock indices in trauma patients with normal shock indices upon emergency department arrival were predictors of a high risk of mortality.

METHODS

We conducted a retrospective cohort study of emergency department-admitted trauma patients from 2004 to 2017. The study included 89,495 consecutive trauma patients aged ≥16 years, with Abbreviated Injury Scale score of ≥3, who were transported to the emergency department directly from the field and had a normal shock index upon emergency department arrival. According to the prehospital shock index scores, the patients were categorized into low shock index (≤ 0.4), normal shock index, and high shock index (≥0.9) groups. Odds ratios and 95% confidence intervals were calculated using logistic regression analysis.

RESULTS

The 89,495 patients had a median age of 64 (interquartile range: 43-79) years, and 55,484 (62.0%) of the patients were male. There were 1350 (1.5%) 24-h deaths in total; 176/4263 (4.1%), 1017/78,901 (1.3%), and 157/6331 (2.5%) patients were in the low, normal, and high prehospital shock index groups, respectively. The adjusted odds ratios for 24-h mortality compared with the normal shock index group were 1.63 (95% confidence interval: 1.34-1.99) in the low shock index group and 1.62 (95% confidence interval: 1.31-1.99) in the high shock index group.

CONCLUSION

Trauma patients with abnormal prehospital shock indices but normal shock indices upon emergency department arrival are at a higher risk of 24-h mortality. Identifying these indices could improve triage and targeted care for patients.

Discriminant ability of the shock index, modified shock index, and reverse shock index multiplied by the Glasgow coma scale on mortality in adult trauma patients: a PATOS retrospective cohort study

BACKGROUND

The shock index (SI) predicts short-term mortality in trauma patients. Other shock indices have been developed to improve discriminant accuracy. The authors examined the discriminant ability of the SI, modified SI (MSI), and reverse SI multiplied by the Glasgow Coma Scale (rSIG) on short-term mortality and functional outcomes.

METHODS

The authors evaluated a cohort of adult trauma patients transported to emergency departments. The first vital signs were used to calculate the SI, MSI, and rSIG. The areas under the receiver operating characteristic curves and test results were used to compare the discriminant performance of the indices on short-term mortality and poor functional outcomes. A subgroup analysis of geriatric patients with traumatic brain injury, penetrating injury, and nonpenetrating injury was performed.

RESULTS

A total of 105 641 patients (49±20 years, 62% male) met the inclusion criteria. The rSIG had the highest areas under the receiver operating characteristic curve for short-term mortality (0.800, CI: 0.791-0.809) and poor functional outcome (0.596, CI: 0.590-0.602). The cutoff for rSIG was 18 for short-term mortality and poor functional outcomes with sensitivities of 0.668 and 0.371 and specificities of 0.805 and 0.813, respectively. The positive predictive values were 9.57% and 22.31%, and the negative predictive values were 98.74% and 89.97%. rSIG also had better discriminant ability in geriatrics, traumatic brain injury, and nonpenetrating injury.

CONCLUSION

The rSIG with a cutoff of 18 was accurate for short-term mortality in Asian adult trauma patients. Moreover, rSIG discriminates poor functional outcomes better than the commonly used SI and MSI.

Shock index as predictor of massive transfusion and mortality in patients with trauma: a systematic review and meta-analysis

BACKGROUND

Management of bleeding trauma patients is still a difficult challenge. Massive transfusion (MT) requires resources to ensure the safety and timely delivery of blood products. Early prediction of MT need may be useful to shorten the time process of blood product preparation. The primary aim of this study was to assess the accuracy of shock index to predict the need for MT in adult patients with trauma. For the same population, we also assessed the accuracy of SI to predict mortality.

METHODS

This systematic review and meta-analysis was performed in accordance with the PRISMA guidelines. We performed a systematic search on MEDLINE, Scopus, and Web of Science from inception to March 2022. Studies were included if they reported MT or mortality with SI recorded at arrival in the field or the emergency department. The risk of bias was assessed using the QUADAS-2.

RESULTS

Thirty-five studies were included in the systematic review and meta-analysis, for a total of 670,728 patients. For MT the overall sensibility was 0.68 [0.57; 0.76], the overall specificity was 0.84 [0.79; 0.88] and the AUC was 0.85 [0.81; 0.88]. Positive and Negative Likelihood Ratio (LR+; LR-) were 4.24 [3.18-5.65] and 0.39 [0.29-0.52], respectively. For mortality the overall sensibility was 0.358 [0.238; 0.498] the overall specificity 0.742 [0.656; 0.813] and the AUC 0.553 (confidence region for sensitivity given specificity: [0.4014; 0.6759]; confidence region for specificity given sensitivity: [0.4799; 0.6332]). LR+ and LR- were 1.39 [1.36-1.42] and 0.87 [0.85-0.89], respectively.

CONCLUSIONS

Our study demonstrated that SI may have a limited role as the sole tool to predict the need for MT in adult trauma patients. SI is not accurate to predict mortality but may have a role to identify patients with a low risk of mortality.

Characteristics and Outcomes of Prehospital Tourniquet Use for Trauma in the United States

INTRODUCTION

The use of the extremity tourniquet in military environments has reduced preventable deaths due to exsanguinating hemorrhage, leading to increased use in civilian settings. However, the outcomes of contemporary prehospital tourniquet use in civilian settings are not well-described nationally. The objective of this study was to describe the characteristics and outcomes following prehospital tourniquet use by emergency medical services (EMS) in the United States.

METHODS

All trauma activations reported to the National EMS Information System 2019 (NEMSIS) were included. Patients who had ≥1 tourniquet applied were identified. Descriptive analyses were used to compare characteristics between tourniquet and no-tourniquet cohorts. Coarsened exact matching was performed to generate a k2k match (on age, sex, lowest-systolic blood pressure, initial patient acuity, provider's initial impression, injury mechanism, and presence of upper/lower extremity injuries) and used to compare outcomes. Trauma patients who may have potentially benefited from tourniquet application (extremity injury, shock index ≥1 and no documented tourniquet application) were identified.

RESULTS

A total of 7,161 tourniquets were applied among 4,571,379 trauma activations (1.6/1000 activations). Patients in the tourniquet cohort were younger (40 ± 18 vs 52 ± 26 mean ± SD years), more hypotensive (16.1% vs. 2.5%) and had higher initial acuity (65.0% critical/emergent vs. 20.6%) [p < 0.01 for all]. A total of 7,074 patients in the tourniquet cohort were matched with 7,074 patients in the non-tourniquet cohort. Post-match analysis revealed that the patients in tourniquet cohort had a higher final acuity (80.8% vs. 75.0%, p < 0.01), lower scene-time (15.4 ± 13.6 vs. 17.0 ± 14.2 mean ± SD minutes, p < 0.01), and higher survival-to-hospital (83.6% vs. 75.1%, p < 0.01). A total of 141,471 trauma patients who may have potentially benefited from tourniquet application were identified.

CONCLUSION

Prehospital tourniquet use by EMS in the United States is associated with lower scene-time and improved survivability to hospital. Results indicate that patients might benefit from wider tourniquet use in the civilian prehospital setting.

Heart rate and diastolic arterial pressure in cardiac arrest patients: A nationwide, multicenter prospective registry

Background

Guidelines have recommended monitoring mean arterial pressure (MAP) and systolic arterial pressure (SAP) in cardiac arrest patients, but there has been relatively little regard for diastolic arterial pressure (DAP) and heart rate (HR). We aimed to determine the prognostic significance of hemodynamic parameters at all time points during targeted temperature management (TTM).

Methods

We reviewed the SAP, DAP, MAP, and HR data in out-of-hospital cardiac arrest (OHCA) survivors from the prospective multicenter registry of 22 teaching hospitals. This study included 1371 patients who underwent TTM among 10,258 cardiac arrest patients. The hemodynamic parameters were recorded every 6 hours from the return of spontaneous circulation (ROSC) to 4 days. The risks of those according to time points during TTM were compared.

Results

Of the included patients, 943 (68.8%) had poor neurological outcomes. The predictive ability of DAP surpassed that of SAP and MAP at all time points, and among the hemodynamic variables HR/DAP was the best predictor of the poor outcome. The risks in patients with DAP < 55 to 70 mmHg and HR > 70 to 100 beats/min were steeply increased for 2 days after ROSC and correlated with the poor outcome at all time points. Bradycardia showed lower risks only at 6 hours to 24 hours after ROSC.

Conclusion

Hemodynamic parameters should be intensively monitored especially for 2 days after ROSC because cardiac arrest patients may be vulnerable to hemodynamic instability during TTM. Monitoring HR/DAP can help access the risks in cardiac arrest patients.

New Injury Severity Score and Trauma Injury Severity Score are superior in predicting trauma mortality

BACKGROUND

Trauma scores are used to give clinicians appropriate quantitative context in making decisions. Studies show that anatomical trauma scores predicted intensive care unit admission better, while physiological trauma scores predicted mortality better. We hypothesize that trauma scores have a hierarchy of efficacies at predicting mortality and operative decision making.

METHODS

We performed a retrospective analysis of our trauma patient database at a level 1 trauma center from 2016 to 2020 and calculated the following trauma scores: Glasgow Coma Scale, Revised Trauma Score, Trauma Injury Severity Score, Injury Severity Score, Shock Index, and New Trauma Injury Severity Score (NISS). Receiver operating characteristic curves were used to evaluate the sensitivity and specificity of trauma scores for predicting mortality.

RESULTS

A total of 738 patients were included (mean ± SD age, 35.7 ± 15.6 years). Area under the curve (AUC) results from the DeLong test showed that NISS predicted mortality the best compared with other trauma scores. New Trauma Injury Severity Score was superior in predicting mortality for penetrating trauma (AUC, 0.86 ± 0.02; p < 0.001) compared with blunt trauma (AUC, 0.73 ± 0.04; p < 0.001). Trauma Injury Severity Score was the best predictor of mortality for patients with gunshot wounds (AUC, 0.83; 95% confidence interval [CI], 0.73-0.92; p < 0.001), motor vehicle accidents (AUC, 0.80; 95% CI, 0.61-1.00; p = 0.01), and falls (AUC, 0.73; 95% CI, 0.61-0.85; p = 0.007).

CONCLUSION

New Trauma Injury Severity Score was the best scoring index for predicting mortality in trauma patients, especially for penetrating trauma. Clinicians should consider incorporating other trauma scores, especially NISS and Trauma Injury Severity Score, in determining injury severity and the likelihood of mortality. These scores can help physicians determine the best course of action in patient management.

LEVEL OF EVIDENCE

Prognostic and Epidemiologic; level IV.

Association between blood pressure and the risk of biopsy-induced endobronchial hemorrhage during bronchoscopy

BACKGROUND

Hemorrhage is one of the most common complications of bronchoscopy. Although several hemorrhage risk factors have been proposed, it remains unclear whether blood pressure affects the onset of biopsy-induced endobronchial hemorrhage.

METHODS

We conducted a retrospective cohort study of 643 consecutive adults with lung cancer over an approximately 4-year period (from January 2014 to February 2018) at a large tertiary care hospital. Patients were divided into the hemorrhage group and the non-hemorrhage group based on endobronchial biopsy (EBB) findings. The association between systolic pressure (SP), diastolic pressure (DP), mean arterial pressure (MAP), pulse pressure (PP), PP to DP ratio (PP/DP) and the risk of EBB-induced hemorrhage was evaluated using multivariate regression analysis and smooth curve fitting adjusted for potential confounding factors.

RESULTS

The EBB-induced bleeding incidence was 37.8% (243/643) in our cohort. An independent association was found between PP/PD and the EBB-induced hemorrhage risk (per 1 SD, adjusted odds ratio, 0.788; 95% confidence interval, 0.653-0.951). The multivariate regression analysis performed using quartiles of PP/DP revealed that lower level of PP/DP ratio was related to a higher risk of EBB-induced hemorrhage (P for trend <0.05) after adjustment for potential confounders. However, no association was observed between SP, DP, MAP, PP and EBB-induced hemorrhage.

CONCLUSIONS

Low PP/DP was the independent risk factor for biopsy-induced endobronchial hemorrhage during bronchoscopy in patients with lung cancer.

Improved identification of severely injured pediatric trauma patients using reverse shock index multiplied by Glasgow Coma Scale

BACKGROUND

The shock index pediatric age-adjusted (SIPA) predicts the need for increased resources and mortality among pediatric trauma patients without incorporating neurological status. A new scoring tool, rSIG, which is the reverse shock index (rSI) multiplied by the Glasgow Coma Scale (GCS), has been proven superior at predicting outcomes in adult trauma patients and mortality in pediatric patients compared with traditional scoring systems. We sought to compare the accuracy of rSIG to Shock Index (SI) and SIPA in predicting the need for early interventions in civilian pediatric trauma patients.

METHODS

Patients (aged 1-18 years) in the 2014 to 2018 Pediatric Trauma Quality Improvement Program database with complete heart rate, systolic blood pressure, and total GCS were included. Optimal cut points of rSIG were calculated for predicting blood transfusion within 4 hours, intubation, intracranial pressure monitoring, and intensive care unit admission. From the optimal thresholds, sensitivity, specificity, and area under the curve were calculated from receiver operating characteristics analyses to predict each outcome and compared with SI and SIPA.

RESULTS

A total of 604,931 patients with a mean age of 11.1 years old were included. A minority of patients had a penetrating injury mechanism (5.6%) and the mean Injury Severity Score was 7.6. The mean SI and rSIG scores were 0.85 and 18.6, respectively. Reverse shock index multiplied by Glasgow Coma Scale performed better than SI and SIPA at predicting early trauma outcomes for the overall population, regardless of age.

CONCLUSION

Reverse shock index multiplied by Glasgow Coma Scale outperformed SI and SIPA in the early identification of traumatically injured children at risk for early interventions, such as blood transfusion within 4 hours, intubation, intracranial pressure monitoring, and intensive care unit admission. Reverse shock index multiplied by Glasgow Coma Scale adds neurological status in initial patient assessment and may be used as a bedside triage tool to rapidly identify pediatric patients who will likely require early intervention and higher levels of care.

LEVEL OF EVIDENCE

Prognostic, level III.

Outcomes of Trauma Patients Present to the Emergency Department with a Shock Index of ≥1.0

Introduction

The study aimed primarily to evaluate the association between the initial shock index (SI) ≥1.0 with blood transfusion requirement in the emergency department (ED) after acute trauma. The study's secondary aim was to look at the outcomes regarding patients' disposition from ED, intensive care unit (ICU) and hospital length of stay, and deaths.

Methods

It was a retrospective, cross-sectional study and utilized secondary data from the Saudi Trauma Registry (STAR) between September 2017 and August 2020. We extracted the data related to patient demographics, mechanism of injuries, the intent of injuries, mode of arrival at the hospital, characteristics on presentation to ED, length of stay, and deaths from the database and compared between two groups of SI <1.0 and SI ≥1.0. A P < 0.05 was statistically considered significant.

Results

Of 6667 patients in STAR, 908 (13.6%) had SI ≥1.0. With SI ≥1.0, there was a significantly higher incidence of blood transfusion in ED compared to SI <1.0 (8.9% vs. 2.4%, P < 0.001). Furthermore, SI ≥ 1.0 was associated with significant ICU admission (26.4% vs. 12.3%, P < 0.001), emergency surgical intervention (8.5% vs. 2.8%, P < 0.001), longer ICU stay (5.0 ± 0.36 vs. 2.2 ± 0.11days, P < 0.001), longer hospital stays (14.8 ± 0.61 vs. 13.3 ± 0.24 days, P < 0.001), and higher deaths (8.4% vs. 2.8%, P < 0.001) compared to the patient with SI <1.0.

Conclusions

In our cohort, a SI ≥ 1.0 on the presentation at the ED carried significantly worse outcomes. This simple calculation based on initial vital signs may be used as a screening tool and therefore incorporated into initial assessment protocols to manage trauma patients.

Comparison of 4 Different Threshold Values of Shock Index in Predicting Mortality of COVID-19 Patients

OBJECTIVE

The object of this study was to examine the accuracy in prehospital shock index (SI) for predicting intensive care unit (ICU) requirement and 30-d mortality among from coronavirus disease 2019 (COVID-19) patients transported to the hospital by ambulance.

METHODS

All consecutive patients who were the age ≥18 y, transported to the emergency department (ED) by ambulance with a suspected or confirmed COVID-19 in the prehospital frame were included in the study. Four different cutoff points were compared (0.7, 0.8, 0.9, and 1.0) to examine the predictive performance of both the mortality and ICU requirement of the SI. The receiver operating characteristic (ROC) curve and the area under the curve (AUC) was used to evaluate each cut-off value discriminatory for predicting 30-d mortality and ICU admission.

RESULTS

The total of 364 patients was included in this study. The median age in the study population was 69 y (range, 55-80 y), of which 196 were men and 168 were women. AUC values for 30-d mortality outcome were calculated as 0.672, 0.674, 0.755, and 0.626, respectively, for threshold values of 0.7, 0.8, 0.9 and 1.0. ICU admission was more likely for the patients with prehospital SI > 0.9. Similarly, the mortality rate was higher in patients with prehospital SI > 0.9.

CONCLUSIONS

Early triage of COVID-19 patients will ensure efficient use of health-care resources. The SI could be a helpful, fast, and powerful tool for predicting mortality status and ICU requirements of adult COVID-19 patients. It was concluded that the most useful threshold value for the shock index in predicting the prognosis of COVID-19 patients is 0.9.

Injury burdens and care delivery in relation to the COVID-19 pandemic in Kigali, Rwanda: A prospective interrupted cross-sectional study

Introduction

Injuries cause significant burdens in sub-Saharan Africa. In Rwanda, national regulations to reduce COVID-19 altered population mobility and resource allocations. This study evaluated epidemiological trends and care among injured patients preceding and during the COVID-19 pandemic at the Centre Hospitalier Universitaire de Kigali (CHUK) in Kigali, Rwanda.

Methods

This prospective interrupted cross-sectional study enrolled injured adult patients (≥15 years) presenting to the CHUK emergency department (ED) from January 27th-March 21st (pre-COVID-19 period) and June 1st-28th (intra-COVID-19 period). Trained study personnel continuously collected standardized data on enrolled participants through the first six-hours of ED care. The Kampala Trauma Score (KTS) was calculated as a metric of injury severity. Case characteristics prior to and during the pandemic were compared, statistical differences were assessed using χ² or Fisher's exact tests.

Results

Data were collected from 409 pre-COVID-19 and 194 intra-COVID-19 cases. Median age was 32, with a male predominance (74.3%). Road traffic injuries (RTI) were the most common injury mechanism pre-COVID-19 (47.8%) and intra-COVID-19 (53.6%) (p = 0.27). There was a significant increase in the number of transfer cases during the intra-COVID-19 period (52.1%) versus pre-COVID-19 (41.3%) (p = 0.01). KTS was significantly lower among intra-COVID-19 patients (p = 0.04), indicating higher severity of presentation. In the intra-COVID-19 period, there was a significant increase in the number of surgery consultations (40.7%) versus pre-COVID-19 (26.7%) (p < 0.001). The number of hospital admissions increased from 35.5% pre-COVID-19 to 46.4% intra-COVID-19 (p = 0.01). There was no significant mortality difference pre-COVID-19 as compared to the intra-COVID-19 period among injured patients (p = 0.76).

Conclusion

Emergency injury care showed increased injury burden, inpatient admission and resource requirements during the pandemic period. This suggests the spectrum of disease may be more severe and that greater resources for injury management may continue to be needed during the ongoing COVID-19 pandemic in Rwanda and other similar settings.

Predicting mortality in trauma patients - A retrospective comparison of the performance of six scoring systems applied to polytrauma patients from the emergency centre of a South African central hospital

Introduction

Over 90% of trauma-related deaths worldwide, ensue in low- and middle-income countries. Multiple useful trauma scoring systems have been devised. Although validated in high-income countries, they cannot always be replicated in resource-limited countries. This study compares six trauma scores to identify the best-suited system to use for polytrauma patients in a hospital in Pretoria, South Africa.

Methods

This is an observational retrospective analysis of polytrauma admissions from 1 July 2016 to 31 December 2016. Data collected from patients' records from the EC of Steve Biko Academic Hospital, was analysed using Stata Release 14. Outcomes were recorded as 30-day survival, ICU– and overall hospital LOS. Scores pertaining to patient mortality, were compared in terms of sensitivity, specificity, and cut-off points based on ROC curve. Finally, for LOS Pearson correlation analysis was used.

Results

At the best calculated mortality prediction cut-points for the scores, the sensitivities and specificities were respectively 87% and 68% for TRISS, 81% and 61% for ISS, RTS yielded 81% and 60%, while for REMS it was 61% and 69%. The SI and RSI (cut-points used in agreement with the literature) produced sensitivities 58% and only 48%, and specificities of 73% and 83%, respectively.

45(41,7%) patients required ICU admission. Though the ICU LOS best correlated with ISS(r = 0.2710), the ICU LOS correlation coefficient was weak for all trauma scores. None of the scores had a significant p value for hospital LOS.

Discussion

Among the scores compared, TRISS had the highest sensitivity and NPV for mortality prediction in this South African polytrauma population. ISS correlated best with ICU LOS. However, compared to developed countries, ROC analyses & predictability of these scores fare relatively worse, and no correlation was found with hospital LOS. Therefore, we conclude that further studies are needed to ascertain a more suitable system for resource-limited settings.

Machine Learning for Military Trauma: Novel Massive Transfusion Predictive Models in Combat Zones

BACKGROUND

Damage control resuscitation has become the standard of care in military and civilian trauma. Early identification of blood product requirements may aid in optimizing the clinical decision-making process while improving trauma related outcomes. This study aimed to assess and compare multiple machine learning models for predicting patients at highest risk for massive transfusion on the battlefield.

METHODS

Supervised machine learning approaches using logistic regression, support vector machine, neural network, and random forest techniques were used to create predictive models for massive transfusion using standard prehospital and arrival data points from the Department of Defense Trauma Registry, 2008-2016. Seventy percent of the population was used for model development and performance was validated using the remaining 30%. Models were tested for accuracy and compared by standard performance statistics.

RESULTS

A total of 22,158 patients (97% male, 58% penetrating injury, median age 25-29 y/o, average Injury Severity Score 9, with an overall mortality of 3%) were included in the analysis. Massive transfusion was required by 7.4% of patients. Overall accuracy was found to be above 90% in all models tested. Following cross validation and model training, the random forest model outperformed the alternatively tested models for precision, recall, and area under the curve.

CONCLUSION

Machine learning techniques may allow for more optimal and rapid identification of combat trauma patients at highest risk for massive transfusion. These powerful approaches may uncover novel correlations and help improve triage, activation of massive transfusion resources, and trauma-related outcomes. Further research seeking to optimize and apply these algorithms to trauma-centered research should be pursued.

Reverse shock index multiplied by Glasgow coma scale as a predictor of massive transfusion in trauma

BACKGROUND AND PURPOSE

Previous studies have identified that the reverse shock index multiplied by the Glasgow Coma Scale score (rSIG) is a good predictor of mortality in trauma patients. However, it is unknown if rSIG has utility as a predictor for massive transfusion (MT) in trauma patients. The present study evaluated the ability of rSIG to predict MT in trauma patients.

METHODS

This was a retrospective, observational study performed at a level 1 trauma center. Consecutive patients who presented to the trauma center emergency department between January 2016 and December 2018 were included. The predictive ability of rSIG for MT was assessed as our primary outcome measure. Our secondary outcome measures were the predictive ability of rSIG for coagulopathy, in-hospital mortality, and 24-h mortality. We compared the prognostic performance of rSIG with the shock index, age shock index, and quick Sequential Organ Failure Assessment.

RESULTS

In total, 1627 patients were included and 117 (7.2%) patients received MT. rSIG showed the highest area under the receiver operating characteristic (AUROC) curve (0.842; 95% confidence interval [CI], 0.806--0.878) for predicting MT. rSIG also showed the highest AUROC for predicting coagulopathy (0.769; 95% CI, 0.728-0.809), in-hospital mortality (AUROC 0.812; 95% CI, 0.772-0.852), and 24-h mortality (AUROC 0.826; 95% CI, 0.789-0.864). The sensitivity of rSIG for MT was 0.79, and the specificity of rSIG for MT was 0.77. All tools had a high negative predictive value and low positive predictive value.

CONCLUSION

rSIG is a useful, rapid, and accurate predictor for MT, coagulopathy, in-hospital mortality, and 24- h mortality in trauma patients.

Early Maladaptive Cardiovascular Responses are Associated with Mortality in a Porcine Model of Hemorrhagic Shock

BACKGROUND

Hemorrhage is a leading cause of death on the battlefield. Current methods for predicting hemodynamic deterioration during hemorrhage are of limited accuracy and practicality. During a study of the effects of remote ischemic preconditioning in pigs that underwent hemorrhage, we noticed arrhythmias among all pigs that died before the end of the experiment but not among surviving pigs. The present study was designed to identify and characterize the early maladaptive hemodynamic responses (tachycardia in the presence of hypotension without a corresponding increase in cardiac index or mean arterial blood pressure) and their predictive power for early mortality in this experimental model.

METHODS

Controlled hemorrhagic shock was induced in 16 pigs. Hemodynamic parameters were monitored continuously for 7 h following bleeding. Changes in cardiovascular and laboratory parameters were analyzed and compared between those that had arrhythmia and those that did not.

RESULTS

All animals had similar changes in parameters until the end of the bleeding phase. Six animals developed arrhythmias and died early, while 10 had no arrhythmias and survived longer than 6 h or until euthanasia. Unlike survivors, those that died did not compensate for cardiac output (CO), diastolic blood pressure (DBP), and stroke volume (SV). Oxygen delivery (DO2) and mixed venous saturation (SvO2) remained low in animals that had arrhythmia, while achieving certain measures of recuperation in animals that did not. Serum lactate increased earlier and continued to rise in all animals that developed arrhythmias. No significant differences in hemoglobin concentrations were observed between groups.

CONCLUSIONS

Despite similar initial changes in variables, we found that low CO, DBP, SV, DO2, SvO2, and high lactate are predictive of death in this animal model. The results of this experimental study suggest that maladaptive responses across a range of cardiovascular parameters that begin early after hemorrhage may be predictive of impending death, particularly in situations where early resuscitative treatment may be delayed.

Prehospital shock index outperforms hypotension alone in predicting significant injury in trauma patients

BACKGROUND

The American College of Surgeons Resources for Optimal Care of the Injured Patient recommends using hypotension, defined as systolic blood pressure ≤90 mm Hg, as an indicator of a full team trauma activation. We hypothesized that an elevated shock index (SI) predicts significant traumatic injuries better than hypotension alone.

METHODS

This is a retrospective cohort study analyzing full team trauma activations between February 2018 and January 2020, excluding transfers and those who had missing values for prehospital blood pressure or heart rate. We reviewed patients' demographics, prehospital and emergency department vitals, injury pattern, need for operation, and clinical outcomes. The primary outcome was rate of significant injury defined as identified injured liver, spleen, or kidney, pelvis fracture, long bone fracture, significant extremity soft tissue damage, hemothorax, or pneumothorax.

RESULTS

Among 544 patients, 82 (15.1%) had prehospital hypotension and 492 had normal blood pressure. Of the patients with prehospital hypotension, 34 (41.5%) had a significant injury. There was no difference in age, gender, medical history, or injury pattern between the two groups. There was no difference between the two groups in rate of serious injury (41.5% vs. 46.1%, NS), need for emergent operation (31.7% vs. 28.1%, NS) or death (20.7% vs. 18.8%, NS). On the other hand, SI ≥1 was associated with increased rate of serious injury (54.6% vs. 43.4%, p=0.04). On a logistic regression analysis, prehospital hypotension was not associated with significant injury or need for emergent operation (OR 0.83, 95% CI 0.51 to 1.33 and OR 1.32, 95% CI 0.79 to 2.25, respectively). SI ≥1 was associated with both increased odds of significant injury and need for emergent operation (OR 1.57, 95% CI 1.01 to 2.44 and OR 1.64, 95% CI 1.01 to 2.66).

DISCUSSION

SI was a better indicator and could replace hypotension to better categorize and triage patients in need of higher level of care.

LEVEL OF EVIDENCE

Prognostic and epidemiologic, level III.

Automated remote decision-making algorithm as a primary triage system using machine learning techniques

OBJECTIVE

An objective and convenient primary triage procedure is needed for prioritizing patients who need help in mass casualty incident (MCI) situations, where there is a lack of medical staff and available resources. This study aimed to develop an automated remote decision-making algorithm that remotely categorize a patient's emergency level using clinical parameters that can be measured with a wearable device.

APPROACH

The algorithm was developed according to the following procedures. First, we used the National Trauma Data Bank data set, a large open trauma patient data set assembled by the American College of Surgeons (ACS). In addition, we performed pre-processing to exclude data when the vital sign or consciousness indicator value was missing or physiologically in an abnormal range. Second, we selected the T-RTS method, which classifies emergency levels into four classes (Delayed, Urgent, Immediate and Dead), as the primary outcome. Third, three machine learning methods widely used in the medical field, logistic regression, random forest, and deep neural network (DNN), were applied to build the algorithm. Finally, each method was evaluated using quantitative performance indicators including the macro-averaged f1 score, macro-averaged mean absolute error (MMAE), and the area under the receiver operating characteristic curve (AUC).

MAIN RESULTS

For total sets, the logistic regression had a macro-averaged f1 score of 0.673, an MMAE of 0.387 and an AUC value of 0.844 (95% CI, 0.843-0.845), while the random forest and DNN had macro-averaged f1 scores of 0.783 and 0.784, MMAEs of 0.297 and 0.298 and AUC values of 0.882 (95% CI, 0.881-0.883) and 0.883(95% CI, 0.881-0.884), respectively.

SIGNIFICANCE

In a comprehensive analysis of these results, our algorithm demonstrated a viable approach that could be practically adopted in an MCI. In addition, it can be employed to transfer patients and to redistribute available resources according to their priorities.

Predicting the need for massive transfusion in the prehospital setting

INTRODUCTION

Massive transfusion (MT) prediction scores allowed for the early identification of patients with massive hemorrhage likely to require large volumes of blood products. Despite their utility, very few MT scoring systems have shown promise in the pre-hospital setting due to their complexity and resource limitations.

AREAS COVERED

Pub med database was utilized to identify supporting literature for this review which discusses the importance of blood-based resuscitation and highlights the utility of scoring systems to predict the need of massive transfusion. MTP scoring systems effective in the prehospital setting are specifically discussed.

EXPERT OPINION

Massive transfusions scores are useful in alerting hospitals to the severity of trauma patients and organizing resources necessary for appropriate patient care but should not completely replace clinical . The opportunity exists to extend their use to the pre-hospital setting to allow for even earlier notification and to triage patients to trauma centers best able to treat severely injured.

Importance of shock index in the evaluation of postpartum hemorrhage cases that necessitate blood transfusion

This study aims to determine cutoff values for shock index (SI) to predict the need for transfusion and composite adverse outcomes in postpartum hemorrhage (PPH) cases. One hundred thirty PPH cases (study group) that necessitated blood transfusion were retrospectively compared to a frequency-matched control group (n = 130). Receiver operating characteristic (ROC) curves and decision tree [Classification & Regression Tree (C&RT) and Chi-square Automatic Interaction Detector (CHAID)] were used to identify cutoff values for SI. Cutoff values for postdelivery, peak and delta SI values for the prediction of PPH that required transfusion were 0.9125 (0.815 sensitivity, 0.923 specificity), 0.9145 (0.892 sensitivity, 0.823 specificity) and 0.195 (0.823 sensitivity, 0.885 specificity), while cutoff values for the same SI values in the prediction of composite adverse outcome were 1.315 (0.645 sensitivity, 0.616 specificity), 1.183 (0.613 sensitivity, 0.737 specificity) and 0.487 (0.710 sensitivity, 0.758 specificity). Delta SI was superior to postdelivery and peak SI in the prediction of PPH that required transfusion. Peak SI was superior to postdelivery and delta SI in the prediction of composite adverse outcome. In conclusion, increased postdelivery, peak, and delta SI values were related to adverse outcomes for PPH. SI seems to be a practical and effective method for the objective assessment of postpartum hemorrhage.

The AdHOC (age, head injury, oxygenation, circulation) score: a simple assessment tool for early assessment of severely injured patients with major fractures

Purpose

We sought to develop a simple, effective and accurate assessment tool using well-known prognostic parameters to predict mortality and morbidity in severely injured patients with major fractures at the stage of the trauma bay.

Methods

European Data from the TraumaRegister DGU^® were queried for patients aged 16 or older and with an ISS of 9 and higher with major fractures. The development (2012–2015) and validation (2016) groups were separated. The four prognostic aspects Age, Head injury, Oxygenation and Circulation along with parameters were identified as having a relevant impact on the outcome of severely injured patients with major fractures. The performance of the score was analyzed with the area under the receiver operating characteristics curve and compared to other trauma scores.

Results

An increasing AdHOC (Age, Head injury, Oxygenation, Circulation) score value in the 17,827 included patients correlated with increasing mortality (0 points = 0.3%, 1 point = 5.3%, 2 points = 15.6%, 3 points = 42.5% and 4 points = 62.6%). With an AUROC of 0.858 for the development (n = 14,047) and 0.877 for the validation (n = 3780) group dataset, the score is superior in performance compared to the Injury Severity Score (0.806/0.815).

Conclusion

The AdHOC score appears to be easy and accessible in every emergency room without the requirement of special diagnostic tools or knowledge of the exact injury pattern and can be useful for the planning of further surgical treatment.

Clinical evaluation of hyperimmune plasma for treatment of dogs with naturally occurring parvoviral enteritis

OBJECTIVE

To evaluate the clinical efficacy of a single infusion of hyperimmune plasma (HIP) in dogs with canine parvovirus (CPV).

DESIGN

Prospective, randomized, placebo-controlled clinical trial.

SETTING

University teaching hospital.

ANIMALS

Client-owned dogs with naturally occurring CPV.

INTERVENTIONS

Dogs presenting for CPV treatment (n = 31) underwent cardiovascular resuscitation and were randomized to receive a single dose of either HIP (10 mL/kg IV) or placebo (0.9% sodium chloride [10 mL/kg IV]) during the first 6 hours of hospitalization. All dogs were treated with a standardized treatment protocol (IV fluid therapy [120 mL/kg/d isotonic crystalloids], cefoxitin [30 mg/kg IV q 8 h], maropitant [1 mg/kg IV q 24 h], and buprenorphine [0.01-0.02 mg/kg IV q 8 h]) until hospital discharge.

MEASUREMENTS AND MAIN RESULTS

Dogs treated with HIP (n = 16) demonstrated a lower shock index at 24 hours (median = 0.77, range: 0.5-1.5) than those treated with placebo (n = 15, median = 1.34, range: 0.5-1.7; P = 0.02). Plasma lactate concentration was lower at 24 hours in HIP-treated dogs (median = 1.3 mmol/L, range: 0.9-3.4 mmol/L) than in placebo-treated dogs (median = 2.1 mmol/L, range: 1.1-3.4 mmol/L; P = 0.01). There was no difference in duration of hospitalization when comparing HIP-treated dogs (median = 3.2 days, range: 0.83-10 days) to placebo-treated dogs (median = 2.83 days, range: 1-8.38 days; P = 0.35). Survival was 16 of 16 (100%) for the HIP group and 14 of 15 (93.3%) for the placebo group (P = 0.32).

CONCLUSIONS

HIP at 10 mL/kg IV administered to dogs with CPV within the first 6 hours of hospitalization improves markers of shock during the initial 24 hours of hospitalization. No effects were observed on duration of hospitalization or mortality; however, this study was underpowered to evaluate these effects. HIP was well tolerated in this population of critically ill dogs.

Patients With Combined Thermal and Intraabdominal Injuries: More Salvageable Than Not

This study aims to better characterize the course and outcome of the uncommon subset of trauma patients with combined thermal and intraabdominal organ injuries. The National Trauma Data Bank was queried for burn patients with intraabdominal injury treated in all U.S. trauma centers from July 1, 2011 to June 30, 2015. General demographics, Glasgow coma scale (GCS), shock index (SI), Abbreviated Injury Scale (AIS) for burn, Injury Severity Score (ISS), blood transfusions, and abdominal surgery were evaluated. During the 5-year study period, there were 334 burn patients with intraabdominal injury, 39 (13.2%) of which received abdominal surgery. Burn patients who underwent operations had more severe injuries reflected by higher SI, AIS, ISS, blood transfusion, and worse outcomes including higher mortality, longer hospital and ICU length of stay, and more ventilator days compared to patients who did not undergo an operation. Nonsurvivors also exhibited more severe injuries, and a higher proportion received abdominal operation compared to survivors. Multivariate logistic regression analysis revealed that GCS on arrival, SI, AIS, ISS, blood transfusion, and abdominal operation to be independent risk factors for mortality. Propensity score matching to control covariables (mean age, systolic blood pressure on arrival, GCS on arrival, SI, ISS, time to operation, blood transfusion, and comorbidities) showed that of trauma patients who received abdominal operation, those with concomitant burn injury exhibited a higher rate of complications but no significant difference in mortality compared to those without burns, suggesting that patients with concomitant burns are not less salvageable than nonburned trauma patients.

Optimal Prospective Predictors of Mortality in Austere Environments

BACKGROUND

Prospective predictors of trauma-related outcomes have been validated to guide management in low-resource settings. The primary objective of this study was to determine the optimal prospective prediction method for mortality within combat and humanitarian trauma.

MATERIALS AND METHODS

Retrospective review of the Department of Defense Trauma Registry from 2008 to 2016 was performed for adult patients. Areas under receiver operating characteristic curves (AUROCs) were calculated to assess the predictability of shock index (SI), reverse SI × Glasgow Coma Scale (rSIG), SI × Glasgow Coma Scale (SIG), Revised Trauma Score, and Trauma and Injury Severity Score (TRISS) on mortality at point of injury, arrival in emergency department (ED), and the difference in vital signs between those time points.

RESULTS

A total of 22,218 patients were included. Overall, 97.1% were male, median age range 25-29 y, Injury Severity Score 9.4 ± 0.07, with predominantly penetrating injuries (58.1%), and mortality of 3.4%. ED vitals yielded higher predictability of mortality for all tests based on higher AUROCs. TRISS and rSIG demonstrated the highest AUROCs (0.955 and 0.923, respectively). The optimal cutoff value for rSIG was 14.1 (sensitivity 89% and specificity 87%). rSIG values <14.1 were significantly associated with mortality (P < 0.01; odds ratio = 5.901).

CONCLUSIONS

Initial ED vital signs represented a better predictor of early mortality compared with point of injury vital signs for all predictive tools assessed. TRISS and rSIG proved to be most predictive of mortality. However, of the prospective tools assessed, rSIG may be optimal scoring tool because of its ease of calculation and its increased ability to predict mortality.

Confusion, respiratory rate, shock index (CRSI-65) score in the emergency department triage may be a new severity scoring method for community-acquired pneumonia

Objectives:

To investigate whether confusion, respiratory rate, shock index-age ≥65 years (CRSI-65) score, consisting of basic physiological parameters, can be used for severity prediction in patients with community-acquired pneumonia.

Methods:

This is a prospective cohort and single-center study conducted in Bolu Abant Izzet Baysal University Hospital, Bolu, Turkey between January 2018 and June 2018. The study investigated CRSI-65 score in predicting 4-week mortality and the need for intensive care for patients with community-acquired pneumonia.

Results:

A total of 58 patients with community-acquired pneumonia admitted to the emergency department were included in this study. Of the patients, 62.1% were males (n=36), and the mean age of the patients was 72.87 ± 12.30 years. After 4 weeks of follow-up, CURB-65 and CRSI-65 scores showed similar results in predicting mortality with respect to specificity, sensitivity, and positive and negative predictive values. Area under the receiver operating characteristic curve was 0.926 for the CURB-65 (95% confidence interval [CI] 0.853-0.999) and 0.954 for the CRSI-65 (95% CI 0.899-0.999).

Conclusion:

Similar to the CURB-65 score, the CRSI-65 score appears to be useful in predicting 4-week mortality. The evaluation of CRSI-65 score can be used in emergency department triage, primary care, and non-hospital settings.

Shock Index as a Marker for Mortality Rates in Those Admitted to the Medical Intensive Care Unit from the Emergency Department

Objective

Shock index (SI) is defined as the heart rate divided by systolic blood pressure. Studies have shown a correlation between the shock index and mortality in trauma patients in prehospital settings and in the emergency department (ED). The objective of this study was to identify the utility of SI in predicting mortality in the medical intensive care unit (MICU) patients admitted from the ED and transfers from the floor to MICU. 

Design

We performed a retrospective analysis of adult patients admitted to the MICU at our urban trauma hospital between January 2015 through August 2015 using ED vital signs to calculate the shock index and identify inpatient deaths. Similar data were examined for inpatient transfers to the MICU.

Results

Nine hundred and fifty patients were included in the study; 743 had an SI ≤ 0.99 with a mortality rate of 15.9%. Two hundred and seven patients had a SI ≥ 1.00 with a mortality rate of 22.7%. A higher SI was significant for mortality. There was no statistical significance in SI and mortality rate for patients transferred from the medical floor to the ICU.

Conclusions

Patients with an SI ≥ 1.00 from initial ED vital signs correlated with a higher mortality rate. In patients transferred from the floor to MICU, SI ≥ 1.00 did not correlate with a higher mortality rate.

Diastolic shock index and clinical outcomes in patients with septic shock

Background

Loss of vascular tone is a key pathophysiological feature of septic shock. Combination of gradual diastolic hypotension and tachycardia could reflect more serious vasodilatory conditions. We sought to evaluate the relationships between heart rate (HR) to diastolic arterial pressure (DAP) ratios and clinical outcomes during early phases of septic shock.

Methods

Diastolic shock index (DSI) was defined as the ratio between HR and DAP. DSI calculated just before starting vasopressors (Pre-VPs/DSI) in a preliminary cohort of 337 patients with septic shock (January 2015 to February 2017) and at vasopressor start (VPs/DSI) in 424 patients with septic shock included in a recent randomized controlled trial (ANDROMEDA-SHOCK; March 2017 to April 2018) was partitioned into five quantiles to estimate the relative risks (RR) of death with respect to the mean risk of each population (assumed to be 1). Matched HR and DAP subsamples were created to evaluate the effect of the individual components of the DSI on RRs. In addition, time-course of DSI and interaction between DSI and vasopressor dose (DSI*NE.dose) were compared between survivors and non-survivors from both populations, while ROC curves were used to identify variables predicting mortality. Finally, as exploratory observation, effect of early start of vasopressors was evaluated at each Pre-VPs/DSI quintile from the preliminary cohort.

Results

Risk of death progressively increased at gradual increments of Pre-VPs/DSI or VPs/DSI (One-way ANOVA, p < 0.001). Progressive DAP decrease or HR increase was associated with higher mortality risks only when DSI concomitantly increased. Areas under the ROC curve for Pre-VPs/DSI, SOFA and initial lactate were similar, while mean arterial pressure and systolic shock index showed poor performances to predict mortality. Time-course of DSI and DSI*NE.dose was significantly higher in non-survivors from both populations (repeated-measures ANOVA, p < 0.001). Very early start of vasopressors exhibited an apparent benefit at higher Pre-VPs/DSI quintile.

Conclusions

DSI at pre-vasopressor and vasopressor start points might represent a very early identifier of patients at high risk of death. Isolated DAP or HR values do not clearly identify such risk. Usefulness of DSI to trigger or to direct therapeutic interventions in early resuscitation of septic shock need to be addressed in future studies.

Can the shock index be a reliable predictor of early mortality after trauma in older patients? A retrospective cohort study

Aim

Older patients have different physiological characteristics; thus, the reliability of the shock index (SI) to predict mortality could depend on age. We investigated whether the SI is a reliable predictor of early mortality in older patients and evaluated the clinical benefit of age in the interpretation of the SI.

Methods

Using data from the Japan Trauma Data Bank, we identified injured patients aged 20–84 years. Area under the receiver operating characteristic curve (AUC) was used to evaluate the discrimination ability of the SI to predict early mortality. A formula to determine the cut‐off for each age was derived using linear regression analysis. Performance of the new method was compared with that of the traditional SI cut‐off of ≥0.9 AUC.

Results

We analyzed data from 146,802 patients. Early mortality was observed in 4% of patients. The AUC showed a significant negative correlation with age (Spearman's ρ = –0.97, P < 0.001), and it decreased from 0.788 (95% confidence interval [CI], 0.761–0.815) in the 20–24 years age group to 0.660 (95% CI, 0.643–0.676) in those aged 80–84 years. By adjusting for age in the SI interpretation, AUC significantly improved from 0.681 (95% CI, 0.675–0.688) to 0.695 (95% CI, 0.688–0.701) (P < 0.001).

Conclusions

The performance of the SI to predict mortality after trauma was significantly worse in older patients. Even if the SI cut‐off value was adjusted based on age, the decrease in performance was not sufficiently prevented. Our results indicated that clinicians should be cautious when using the SI in older patients.

Shock index in the emergency department: utility and limitations

Shock index (SI) is defined as the heart rate (HR) divided by systolic blood pressure (SBP). It has been studied in patients either at risk of or experiencing shock from a variety of causes: trauma, hemorrhage, myocardial infarction, pulmonary embolism, sepsis, and ruptured ectopic pregnancy. While HR and SBP have traditionally been used to characterize shock in these patients, they often appear normal in the compensatory phase of shock and can be confounded by factors such as medications (eg, antihypertensives, beta-agonists). SI >1.0 has been widely found to predict increased risk of mortality and other markers of morbidity, such as need for massive transfusion protocol activation and admission to intensive care units. Recent research has aimed to study the use of SI in patients immediately on arrival to the emergency department (ED). In this review, we summarize the literature pertaining to use of SI across a variety of settings in the management of ED patients, in order to provide context for use of this measure in the triage and management of critically ill patients.

Prognostic Role of Shock Index in Traumatic Pelvic Fracture: A Retrospective Analysis

BACKGROUND

We aimed to validate the utility of shock index (SI) in predicting the need of blood transfusion and outcomes in patients with traumatic pelvic fracture (TPF).

MATERIALS AND METHODS

We conducted a retrospective analysis for patients who sustained TPF between 2012 and 2016 in a level 1 trauma center. Patients were categorized into patients with low versus high SI based on the cutoff obtained from the receiver operating characteristic curves to predict mortality.

RESULTS

A total of 966 patients sustained TPF (28.5% had SI ≥ 0.9 based on receiver operating characteristic curves) with a median age of 33 (IQR 25-47) y. Type B and C pelvic fractures significantly had higher SI. The frequency of blood transfusion use was greater in patients with high SI (P = 0.001). SI correlated significantly with Injury Severity Score (r = 0.32), Revised Trauma Score (r = -0.40), and transfused blood units (r = 0.35). Patients with high SI had prolonged hospital length of stay and higher mortality (P = 0.001). SI ≥ 0.9 showed high sensitivity and negative predictive value to identify the need of massive blood transfusion (77% and 86%, respectively) and mortality (73.5% and 98.1%, respectively). For hospital mortality, high SI had a sensitivity of 73.5%, specificity 74%, negative predictive value 98%, and negative likelihood ratio of 0.36. After adjustment for age, sex, Injury Severity Score, Glasgow Coma Scale, pelvis Abbreviated Injury Scale, blood transfusion, and Tile classification, the multivariate analysis models showed that high SI was an independent predictor of blood transfusion (odd ratio 5.6) and mortality (odd ratio 3.63).

CONCLUSIONS

SI is a potentially useful instant tool for the prediction of massive transfusion and mortality in patients with TPF. Further prospective studies are warranted to support our findings.

Novel transcatheter arterial embolization method for hemodynamically unstable pelvic fractures to prevent complications of gluteal necrosis

Purpose

To validate our previously designed transcatheter arterial embolization (TAE) technique for bilateral iliac arteries in unstable pelvic fractures, which is designed to also prevent gluteal necrosis and avoid vasopressors.

Methods

We retrospectively analyzed the data of patients with pelvic fractures who underwent our new TAE procedure to determine the incidence of subsequent gluteal necrosis. We also compared certain variables between patients who underwent TAE before 2005 using a different technique and developed gluteal necrosis and patients who underwent TAE in 2005 and onward using our technique. Gluteal necrosis was confirmed by a radiologist based on imaging findings.

Results

Seventy patients with pelvic fractures who underwent our TAE technique met the inclusion criteria (bilateral iliac arterial embolization and no embolic agent other than a gelatin sponge). Patients’ median age was 47.5 years, 33 were male, and 92.9% (65/70) had unstable fractures. Sixty-eight patients had severe multiple trauma. No patients developed gluteal necrosis following our TAE procedure and the overall survival rate was 82.9% (58/70). We found no statistically significant difference in procedure time between the previous and new technique, although the new procedure tended to be shorter. Furthermore, overall survival did not significantly differ between the groups. Multiple regression analysis revealed that TAE procedure time and external pelvic fracture fixation were independently related to gluteal necrosis.

Conclusions

Our non-selective bilateral iliac arterial embolization procedure involves arresting shock quickly, resulting in no post-procedure gluteal necrosis. The procedure involves cutting the gelatin sponge rather than “pumping” and avoids the use of vasopressors.

Systolic blood pressure lower than the heart rate indicates a poor outcome in patients with severe isolated traumatic brain injury: A cross-sectional study

BACKGROUND

A systolic blood pressure (SBP) lower than the heart rate (HR) could indicate a poor condition in trauma patients. In such scenarios, the reversed shock index (RSI) is < 1, as calculated by the SBP divided by the HR. This study aimed to clarify whether RSI could be used to identify high-risk adult patients with isolated traumatic brain injury (TBI).

METHODS

This retrospective study reviewed 1216 hospitalized adult patients with isolated TBI at a Level I trauma center between January 1, 2009 and December 31, 2015. The patients were grouped and analyzed according to RSI (<1 or ≥ 1). Subgroups of patients with severe TBI (Glasgow Coma Scale [GCS] ≤ 8) or non-severe TBI (GCS > 8) were also compared. The primary outcome was in-hospital mortality. The odds ratios (ORs) of categorical variables were calculated by chi-square tests with 95% confidence intervals (CIs). Mann-Whitney U-tests were used to analyze non-normally distributed continuous data.

RESULTS

Among patients with isolated TBI, those with an RSI <1 had higher mortality (44.7% vs. 7.1%, OR: 10.5, 95% CI: 5.36-20.75; P < 0.001) than those with an RSI ≥1. An RSI <1 indicated a higher risk of mortality (OR: 5.1, 95% CI: 2.08-12.49; P < 0.001) in patients with severe isolated TBI but not in patients with non-severe isolated TBI (OR: 3.6, 95% CI: 0.45-28.71; P = 0.267).

CONCLUSION

Patients with isolated TBI may be at risk for shock. In trauma patients with severe isolated TBI, an SBP lower than the HR indicates a poor outcome.

Shock Index-A Useful Noninvasive Marker Associated With Age-Specific Early Mortality in Children With Severe Sepsis and Septic Shock: Age-Specific Shock Index Cut-Offs

BACKGROUND

Aim of the study was to analyze the association of shock index (SI) from 0 to 6 hours with early mortality in severe sepsis/septic shock and to explore its age-specific cut-off values. To investigate association of change in SI over first 6 hours with early mortality.

METHODS

A prospective cohort study of children (<14 years) admitted in emergency department, tertiary care hospital with severe sepsis or septic shock, divided into 3 groups: group 1: 1 month to <1 year; group 2: 1 to <6 years; group 3: 6 to 12 years. Shock index (SI = heart rate/systolic blood pressure) measured at admission (X0) and hourly till 6 hours (X1-6). Primary outcome was death within 48 hours of admission. Area under receiver operating characteristic curves were constructed for SI (0-6). Optimal cut-offs of SI 0 and SI 6, maximizing both sensitivity and specificity were determined and positive and negative predictive values (PPV, NPV) were calculated.

RESULTS

From 2015 to 2016, 120 children were recruited. Septic shock was present at admission in 56.7% children. Early mortality was 50%. All hourly shock indices (SI 0-6) were higher among nonsurvivors in group 2 (P ≤ .03) and group 3 (P < .001). In group 1, SI after 2 hours was higher in nonsurvivors (P 2-6: ≤ .02). Area under receiver operating characteristic curves (95% CI) for SI at 0 hour was 0.72 (0.5-0.9), 0.66 (0.5-0.8), and 0.77 (0.6-0.9) and at 6 hours was 0.8 (0.6-1), 0.75 (0.6-0.9), and 0.8 (0.7-1) in 3 groups. The cut-off values of SI 0 (sensitivity; specificity; PPV; NPV) in 3 groups: 1.98 (77; 75; 67; 83), 1.50 (65; 65; 68; 63), and 1.25 (90; 67; 77; 83) and SI6: 1.66 (85; 80; 73; 89), 1.36 (73; 70; 73; 70), and 1.30 (74; 73; 78; 69). Improvement of SI over 6 hours was associated with better outcome. Children with higher SI at both time points had higher mortality than those with SI score below the cut-offs (P = .001).

CONCLUSIONS

Age-specific SI cut-off values may identify children at high risk of early mortality in severe sepsis/septic shock and allow for better targeted management.