Postpartum hemorrhage: new insights for definition and diagnosis

The current definition of is inadequate for early recognition of this important cause of maternal death that is responsible for >80,000 deaths worldwide in 2015. A stronger definition of postpartum hemorrhage should include both blood loss and clinical signs of cardiovascular changes after delivery, which would help providers to identify postpartum hemorrhage more promptly and accurately. Along with the amount of blood loss, clinical signs, and specifically the shock index (heart rate divided by systolic blood pressure) appear to aid in more accurate diagnosis of postpartum hemorrhage.

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.

Prediction of Massive Transfusion in Trauma Patients with Shock Index, Modified Shock Index, and Age Shock Index

Objectives: The shock index (SI) and its derivations, the modified shock index (MSI) and the age shock index (Age SI), have been used to identify trauma patients with unstable hemodynamic status. The aim of this study was to evaluate their use in predicting the requirement for massive transfusion (MT) in trauma patients upon arrival at the hospital. Participants: A patient receiving transfusion of 10 or more units of packed red blood cells or whole blood within 24 h of arrival at the emergency department was defined as having received MT. Detailed data of 2490 patients hospitalized for trauma between 1 January 2009, and 31 December 2014, who had received blood transfusion within 24 h of arrival at the emergency department, were retrieved from the Trauma Registry System of a level I regional trauma center. These included 99 patients who received MT and 2391 patients who did not. Patients with incomplete registration data were excluded from the study. The two-sided Fisher exact test or Pearson chi-square test were used to compare categorical data. The unpaired Student t-test was used to analyze normally distributed continuous data, and the Mann-Whitney U-test was used to compare non-normally distributed data. Parameters including systolic blood pressure (SBP), heart rate (HR), hemoglobin level (Hb), base deficit (BD), SI, MSI, and Age SI that could provide cut-off points for predicting the patients’ probability of receiving MT were identified by the development of specific receiver operating characteristic (ROC) curves. High accuracy was defined as an area under the curve (AUC) of more than 0.9, moderate accuracy was defined as an AUC between 0.9 and 0.7, and low accuracy was defined as an AUC less than 0.7. Results: In addition to a significantly higher Injury Severity Score (ISS) and worse outcome, the patients requiring MT presented with a significantly higher HR and lower SBP, Hb, and BD, as well as significantly increased SI, MSI, and Age SI. Among these, only four parameters (SBP, BD, SI, and MSI) had a discriminating power of moderate accuracy (AUC > 0.7) as would be expected. A SI of 0.95 and a MSI of 1.15 were identified as the cut-off points for predicting the requirement of MT, with an AUC of 0.760 (sensitivity: 0.563 and specificity: 0.876) and 0.756 (sensitivity: 0.615 and specificity: 0.823), respectively. However, in the groups of patients with comorbidities such as hypertension, diabetes mellitus, or coronary artery disease, the discriminating power of these three indices in predicting the requirement of MT was compromised. Conclusions: This study reveals that the SI is moderately accurate in predicting the need for MT. However, this predictive power may be compromised in patients with HTN, DM or CAD. Moreover, the more complex calculations of MSI and Age SI failed to provide better discriminating power than the SI.

Prehospital parameters can help to predict coagulopathy and massive transfusion in trauma patients

BACKGROUND

This study aimed to evaluate the accuracy of prehospital parameters, including vital signs and resuscitation (fluids, vasopressor), to predict trauma-induced coagulopathy (TIC, fibrinogen <1·5 g/l or PT_ratio > 1·5 or platelet count <100 × 10⁹ /l), and a massive transfusion (MT, ≥10 RBC units within the first 24 h).

METHODS

From a trauma registry (2011-2015), in which patients are prospectively included, we retrospectively retrieved the heart rate (HR), systolic blood pressure (SBP), volume of prehospital fluids and administration of noradrenaline. We calculated the shock index (SI: HR/SBP), the MGAP prehospital triage score and the Injury Severity Score (ISS). We also identified patients who had positive criteria from the Resuscitation Outcome Consortium (ROC, SBP < 70 mmHg or SBP 70-90 and HR > 107 pulse/min). For these parameters, we drew a ROC curve and defined a cut-off value to predict TIC or MT. The strength of association between prehospital parameters and TIC as well as MT was assessed using logistic regression, and cut-off values were determined using ROC curves.

RESULTS

Among the 485 patients included in the study, TIC was observed in 112 patients (23%) and MT in 22 patients (5%). For the prediction of TIC, ISS had good accuracy (AUC: 0·844, 95% confidence interval, CI: 0·799-0·879), as did the volume of fluids (>1000 ml) given during prehospital care (AUC: 0·801, 95% CI: 0·752-0·842). For the prediction of MT, ISS had excellent accuracy (AUC: 0·932, 95% CI: 0·866-0·966), whereas good accuracy was found for SI (> 0·9; AUC: 0·859, 95% CI: 0·705-0·936), vasopressor administration (AUC: 0·828, 95% CI: 0·736-0·890) and fluids (>1000 ml; AUC: 0·811, 95% CI: 0·737-0·867). Vasopressor administration, ISS and SI were independent predictors of TIC and MT, whereas fluid volume and ROC criteria were independent predictor of TIC but not MT. No independent relationship was found between MGAP and TIC or MT.

CONCLUSIONS

Prehospital parameters including the SI and resuscitation may help to better identify the severity of bleeding in trauma patients and the need for blood product administration at admission.

The prognostic value of shock index for the outcomes of acute myocardial infarction patients: A systematic review and meta-analysis

BACKGROUND

Several studies have revealed that high shock index (SI) is a risk factor for acute myocardial infarction (AMI) patients. These studies do not give a systematic review in this issue. Therefore, we conducted a systematic review and meta-analysis to determine the effect of high SI on the prognosis of AMI patients.

METHODS

We did a systematic search of PubMed, Embase, and the Cochrane Library, using various combinations of keywords such as "shock index," "shock-index," "acute myocardial infarction," "ST elevation myocardial infarction," "non-ST segment elevation myocardial infarction," "STEMI," "NSTEMI," "AMI," and "MI" for eligible studies published up to December 23, 2016. The 3 primary outcomes for this analysis were all-cause in-hospital mortality, short-term adverse outcomes, and long-term adverse outcomes.

RESULTS

Database searches retrieved 226 citations. Finally, 8 studies enrolling 20,404 patients were eventually included in the analysis. High SI was associated with an increased in-hospital mortality (pooled RR = 10.96, 95% CI: 2.00-59.94, P = .01). Adverse outcomes were significantly higher in the high SI group compared to the low SI group (pooled RR = 1.93, 95% CI: 1.10-3.39, P = .02; I = 95%). Individuals with high SI had an increased risk of long-term adverse outcomes (pooled RR = 2.31, 95% CI: 1.90-2.81, P < .001) compared to low SI.

CONCLUSION

High SI may increase the in-hospital mortality, short-term, and long-term adverse outcomes in AMI patients.

The assessment of blood pressure in pregnant women: pitfalls and novel approaches

Accurate assessment of blood pressure is fundamental to the provision of safe obstetrical care. It is simple, cost effective, and life-saving. Treatments for preeclampsia, including antihypertensive drugs, magnesium sulfate, and delivery, are available in many settings. However, the instigation of appropriate treatment relies on prompt and accurate recognition of hypertension. There are a number of different techniques for blood pressure assessment, including the auscultatory method, automated oscillometric devices, home blood pressure monitoring, ambulatory monitoring, and invasive monitoring. The auscultatory method with a mercury sphygmomanometer and the use of Korotkoff sounds was previously recommended as the gold standard technique. Mercury sphygmomanometers have been withdrawn owing to safety concerns and replaced with aneroid devices, but these are particularly prone to calibration errors and regular calibration is imperative to ensure accuracy. Automated oscillometric devices are straightforward to use, but the physiological changes in healthy pregnancy and pathologic changes in preeclampsia may affect the accuracy of a device and monitors must be validated. Validation protocols classify pregnant women as a "special population," and protocols must include 15 women in each category of normotensive pregnancy, hypertensive pregnancy, and preeclampsia. In addition to a scarcity of devices validated for pregnancy and preeclampsia, other pitfalls that cause inaccuracy include the lack of training and poor technique. Blood pressure assessment can be affected by maternal position, inappropriate cuff size, conversation, caffeine, smoking, and irregular heart rate. For home blood pressure monitoring, appropriate instruction should be given on how to use the device. The classification of hypertension and hypertensive disorders of pregnancy has recently been revised. These are classified as preeclampsia, transient gestational hypertension, gestational hypertension, white-coat hypertension, masked hypertension, chronic hypertension, and chronic hypertension with superimposed preeclampsia. Blood pressure varies across gestation and by ethnicity, but gestation-specific thresholds have not been adopted. Hypertension is defined as a sustained systolic blood pressure of ≥140 mm Hg or a sustained diastolic blood pressure of ≥90 mm Hg. In some guidelines, the threshold of diagnosis depends on the setting in which blood pressure measurement is taken, with a threshold of 140/90 mm Hg in a healthcare setting, 135/85 mm Hg at home, or a 24-hour average blood pressure on ambulatory monitoring of >126/76 mm Hg. Some differences exist among organizations with respect to the criteria for the diagnosis of preeclampsia and the correct threshold for intervention and target blood pressure once treatment has been instigated. Home blood pressure monitoring is currently a focus for research. Novel technologies, including early warning devices (such as the CRADLE Vital Signs Alert device) and telemedicine, may provide strategies that prompt earlier recognition of abnormal blood pressure and therefore improve management. The purpose of this review is to provide an update on methods to assess blood pressure in pregnancy and appropriate technique to optimize accuracy. The importance of accurate blood pressure assessment is emphasized with a discussion of preeclampsia prediction and treatment of severe hypertension. Classification of hypertensive disorders and thresholds for treatment will be discussed, including novel developments in the field.

Extremes of shock index predicts death in trauma patients

Context:

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

Aims:

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

Settings and Designs:

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

Materials and Methods:

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

Statistical Analysis Used:

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

Conclusion:

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

Shock Index Predicts Outcome in Patients with Suspected Sepsis or Community-Acquired Pneumonia: A Systematic Review

Background: To improve outcomes for patients who present to hospital with suspected sepsis, it is necessary to accurately identify those at high risk of adverse outcomes as early and swiftly as possible. To assess the prognostic accuracy of shock index (heart rate divided by systolic blood pressure) and its modifications in patients with sepsis or community-acquired pneumonia. Methods: An electronic search of MEDLINE, EMBASE, Allie and Complementary Medicine Database (AMED), Cumulative Index to Nursing and Allied Health Literature (CINAHL), Open Grey, ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform (WHO ITRP) was conducted from conception to 26th March 2019. Eligible studies were required to assess the prognostic accuracy of shock index or its modifications for outcomes of death or requirement for organ support either in sepsis or pneumonia. The methodological appraisal was carried out using the Downs and Black checklist. Evidence was synthesised using a narrative approach due to heterogeneity. Results: Of 759 records screened, 15 studies (8697 patients) were included in this review. Shock index ≥ 1 at time of hospital presentation was a moderately accurate predictor of mortality in patients with sepsis or community-acquired pneumonia, with high specificity and low sensitivity. Only one study reported outcomes related to organ support. Conclusions: Elevated shock index at time of hospital presentation predicts mortality in sepsis with high specificity. Shock index may offer benefits over existing sepsis scoring systems due to its simplicity.

Shock index thresholds to predict adverse outcomes in maternal hemorrhage and sepsis: A prospective cohort study

Introduction

Shock index (SI) is a predictor of hemodynamic compromise in obstetric patients. The SI threshold for action is not well understood. We aimed to evaluate SI thresholds as predictors of outcomes in obstetric patients.

Material and methods

We undertook a prospective cohort study at three South African hospitals of women with postpartum hemorrhage (n = 283) or maternal sepsis (n = 126). The “first” and “worst” SI following diagnosis were recorded. SI was compared with conventional vital signs as predictors of outcomes. The performance of SI <.9, SI .9‐1.69 and SI ≥1.7 to predict outcomes (maternal death; Critical Care Unit admission; major procedure; hysterectomy) and hemorrhage‐specific outcomes (lowest hemoglobin <70 g/l; blood transfusion ≥4 IU) were evaluated.

Results

“First” SI was one of two best performing vital signs for every outcome in postpartum hemorrhage and sepsis. In hemorrhage, risk of all outcomes increased with increasing “first” SI; for blood transfusion ≥4 IU odds ratio was 4.24 (95% confidence interval 1.25‐14.36) for SI ≥1.7 vs SI .9‐1.69. In sepsis, risk of all outcomes increased with increasing “worst” SI. Sensitivity, specificity, positive and negative predictive values of “first” SI <.9 vs SI ≥.9 for maternal death were 100.0%, 55.2%, 4.6% and 100.0%, respectively, in hemorrhage and 80.0%, 50.4%, 12.3% and 96.7%, respectively, in sepsis.

Conclusions

The shock index was a consistent predictor of outcomes compared with conventional vital signs in postpartum hemorrhage and sepsis. SI <.9 performed well as a rule‐out test and SI .9‐1.69 and SI ≥1.7 indicated increased risk of all outcomes in both cohorts. These thresholds may alert to the need for urgent intervention and prevent maternal deaths.

Shock Index Predicts Patient-Related Clinical Outcomes in Stroke

Background

The prognostic value of shock index (SI), heart rate divided by systolic blood pressure, in stroke for clinical outcomes other than mortality is not well understood.

Methods and Results

We examined the Get With The Guidelines–Stroke (GWTG‐Stroke) data to explore the usefulness of SI in predicting in‐hospital outcomes in 425 808 acute stroke cases (mean age: 71.0±14.5 years; 48.8% male; 89.7% ischemic stroke and 10.3% intracerebral hemorrhage) admitted between October 2012 and March 2015. Compared with patients with SI of 0.5 to 0.7, patients with SI >0.7 (13.6% of the sample) had worse outcomes, with adjusted odds ratios of 2.00 (95% confidence interval [CI], 1.92–2.08) for in‐hospital mortality, 1.46 (95% CI, 1.43–1.49) for longer length of hospital stay >4 days, 1.50 (95% CI, 1.47–1.54) for discharge destination other than home, 1.41 (95% CI, 1.38–1.45) for inability to ambulate independently at discharge, and 1.52 (95% CI, 1.47–1.57) for modified Rankin Scale score of 3 to 6 at discharge. Results were similar when analyses were confined to those with available National Institutes of Health Stroke Scale (NIHSS) or within individual stroke subtypes or when SI was additionally included in the models with or without blood pressure components. Every 0.1 increase in SI >0.5 was associated with significantly worse outcomes in linear spline models. The addition of SI to existing GWTG‐Stroke mortality prediction models without NIHSS demonstrated modest improvement, but little to no improvement was noted in models with NIHSS.

Conclusions

SI calculated at the point of care may be a useful prognostic indicator to identify those with high risk of poor outcomes in acute stroke, especially in hospitals with limited experience with NIHSS assessment.

The Usefulness of Shock Index and Modified Shock Index in Predicting the Outcome of COVID-19 Patients

Objective:

The aim of this study is to investigate the accuracy of shock index (SI) and modified shock index (mSI) in predicting the intensive care unit (ICU) requirement and in-hospital mortality among coronavirus disease (COVID-19) patients who are admitted to the emergency department (ED). Likewise, the effects of patients’ conditions such as age, gender, and comorbidity on prognosis will be analyzed.

Methods:

The files were retrospectively scanned for all COVID-19 patients over the age of 18 years who were admitted to the ED and hospitalized between January 1, 2021, and March 15, 2021. The area under the receiver operating characteristic curve and the area under the curve (AUC) were used to assess each scoring system discriminatory for predicting in-hospital mortality and ICU admission.

Results:

There were 464 patients included in this study. The mean age of the patients was 62.4 ± 16.7, of which 245 were men and 219 were women. The most common comorbidity in patients was hypertension (200; 43.1%), followed by chronic obstructive pulmonary disease (174; 37.5%), and coronary artery disease (154; 33.2%). In terms of in-hospital mortality, the AUC of SI, and mSI were 0.719 and 0.739, respectively. In terms of an ICU requirement, the AUC of SI, and mSI were 0.704 and 0.729, respectively.

Conclusion:

In this study, it was concluded that SI and mSI are useful in predicting in-hospital mortality and ICU requirement in COVID-19 patients. In addition, another important result of the study is that advanced age, male gender, and hypertension may be associated with a poor prognosis.

Lactate and fibrinogen as good predictors of massive transfusion in postpartum hemorrhage

Aim

This study aims to identify the clinical factors that can predict the requirement of massive transfusion among patients with postpartum hemorrhage (PPH).

Methods

Consecutive anonymized patients with PPH who were treated at the emergency department of our perinatal medical center were examined. Patients who had received transfusions before admission, those who had cardiac arrest on arrival, and those without history of blood gas analysis were excluded. Our primary outcome was the requirement of massive transfusion defined as packed red blood cells of ≥10 units/24 h. Univariable logistic analysis was carried out to identify the odds ratio and 95% confidence interval (CI) of the explanatory variables for the outcome.

Results

A total of 31 patients (massive transfusion, n = 19) were included in the main analysis. The crude odds ratio for fibrinogen per mg/dL and lactate per mmol/L were calculated as 0.98 (95% CI, 0.97–0.99) and 1.62 (95% CI, 1.08–3.02), respectively. The area under the curves for fibrinogen and lactate were 0.814 and 0.734, respectively, and optimal cut‐off values for fibrinogen and lactate were 211 mg/dL and 4 mmol/L, respectively.

Conclusion

These findings suggest that lactate and fibrinogen can be predictors for the requirement of massive transfusion in patients with PPH.

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.

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

BACKGROUND

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

AIMS

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

SETTINGS AND DESIGN

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

MATERIALS AND METHODS

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

STATISTICAL ANALYSIS

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

RESULTS

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

CONCLUSIONS

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

The golden hour for postpartum hemorrhage: Results from a prospective cohort study

OBJECTIVE

To evaluate the predictive capacity of vital signs for the diagnosis of postpartum hemorrhage (PPH).

METHODS

A prospective cohort study performed at the University of Campinas, Brazil, between February 2015 and March 2016 with women who delivered vaginally. Vital signs and postpartum bleeding were collected over 24 h. Exploratory data analysis was performed plus receiver operating characteristic curve analysis where the areas under the curve was used to determine the best cutoff points for sensitivity, specificity, likelihood ratio, and diagnostic odds ratio.

RESULTS

For the 270 women recruited, mean blood loss after 120 min was 427.49 ± 335.57 ml, while 84 (31.1%) and 22 (8.1%) women had blood loss ≥500 and ≥1000 ml, respectively. Heart rate cutoff point of 105 bpm measured between 21-40 min after birth identified blood loss ≥1000 ml with 90% specificity. A shock index (SI) of 0.965 at 41-60 min after birth identified blood loss ≥500 and ≥1000 ml within 2 h with approximately 95% specificity.

CONCLUSION

Shock index and heart rate measured after birth showed high specificity with low sensitivity to identify PPH. In clinical practice, "The rule of 1s" should receive special attention: SI ≥1, or heart rate >100 bpm, or estimated blood loss ≥1 L.

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.

Predictive accuracy of the shock index for severe postpartum hemorrhage in high-income countries: A systematic review and meta-analysis

AIM

The shock index has been suggested as a screening tool for predicting postpartum hemorrhage (PPH); however, there is little comprehensive evidence regarding its predictive accuracy. This systematic review and meta-analysis aim to investigate the predictive accuracy of the shock index for severe PPH in high-income countries.

METHODS

A comprehensive search was conducted on MEDLINE, Cochrane Central Register of Controlled Trials, and Web of Science (from inception to June 2021). Studies assessing the predictive performance of the shock index for PPH in high-income countries were included. Two or more reviewers independently extracted the data and assessed the risk of bias and applicability concerns using the modified Quality Assessment of Diagnostic Accuracy Studies 2 tool. PPH requiring higher-level care, such as blood transfusions, were considered as primary analyses. We described the hierarchical summary receiver-operating characteristic curve for data synthesis.

RESULTS

Nine studies were included after the eligibility assessment. All studies were considered to either have a high risk of bias or high applicability concerns. The sensitivity of the four studies that defined severe PPH as PPH requiring blood transfusion ranged from 0.51 to 0.80, whereas their specificity ranged from 0.33 to 0.92.

CONCLUSIONS

This review shows that the predictive performance of the shock index for severe PPH is inconsistent. Therefore, the evidence for using the shock index alone as a screening tool for PPH in high-income countries is insufficient.

STUDY REGISTRATION

This review was prospectively registered with the University Hospital Medical Information Network Clinical Trials Registry (UMIN000044230).

Shock index as a predictor of postpartum haemorrhage after vaginal delivery: Secondary analysis of a multicentre randomised controlled trial

OBJECTIVE

To describe the shock index (SI) distribution during the first 2 hours after delivery and to evaluate its performance when measured 15 and 30 minutes after delivery for predicting postpartum haemorrhage (PPH) occurrence in the general population of parturients after vaginal delivery.

DESIGN

Secondary analysis of a multicentre randomised controlled trial testing prophylactic administration of tranexamic acid versus placebo in addition to prophylactic oxytocin to prevent PPH.

SETTING

15 French maternity units in 2015-2016.

SAMPLE

3891 women with a singleton live fetus ≥35 weeks, born vaginally.

METHODS

For each PPH-related predicted outcome, we calculated the area under the receiver operating characteristic curve (AUROC) values of the SI at 15 and 30 minutes after delivery and its predictive performance for SI cut-off values of 0.7, 0.9 and 1.1.

MAIN OUTCOME MEASURES

Quantitative blood loss ≥1000 ml (QBL ≥1000 ml) measured in a graduated collector bag and provider-assessed clinically significant PPH (cPPH).

RESULTS

Prevalence of QBL ≥1000 ml and cPPH was respectively 2.7% (104/3839) and 9.1% (354/3891). The distributions of the SI at 15 and 30 minutes after delivery were similar with a median value of 0.73 and 97th percentile of 1.11 for both. The AUROC values of the 15-minute SI for discriminating QBL ≥1000 ml and cPPH were respectively 0.66 (lower limit of the 95% confidence interval [LCI] 0.60) and 0.56 (LCI 0.52); and for the 30-minute SI 0.68 (LCI 0.61) and 0.49 (LCI 0.43).

CONCLUSIONS

The shock index at 15 and 30 minutes after delivery did not satisfactorily predict either QBL ≥1000 ml or clinical PPH.

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.

Shock Index: A Simple and Effective Clinical Adjunct in Predicting 60-Day Mortality in Advanced Cancer Patients at the Emergency Department

Deciding between palliative and overly aggressive therapies for advanced cancer patients who present to the emergency department (ED) with acute issues requires a prediction of their short-term survival. Various scoring systems have previously been studied in hospices or intensive care units, though they are unsuitable for use in the ED. We aim to examine the use of a shock index (SI) in predicting the 60-day survival of advanced cancer patients presenting to the ED. Identified high-risk patients and their families can then be counseled accordingly. Three hundred and five advanced cancer patients who presented to the EDs of three tertiary hospitals were recruited, and their data retrospectively analyzed. Relevant data regarding medical history and clinical presentation were extracted, and respective shock indices calculated. Multivariate logistic regression analyses were performed. Receiver operating characteristic (ROC) curves were plotted to evaluate the predictive performance of the SI. Nonsurvivors within 60 days had significantly lower body temperatures and blood pressure, as well as higher pulse rates, respiratory rates, and SI. Each 0.1 SI increment had an odds ratio of 1.39 with respect to 60-day mortality. The area under the ROC curve was 0.7511. At the optimal cut-off point of 0.94, the SI had 81.38% sensitivity and 73.11% accuracy. This makes the SI an ideal evaluation tool for rapidly predicting the 60-day mortality risk of advanced cancer patients presenting to the ED. Identified patients can be counseled accordingly, and they can be assisted in making informed decisions on the appropriate treatment goals reflective of their prognoses.

Comparative study on quick sequential organ failure assessment, systemic inflammatory response syndrome and the shock index in prehospital emergency patients: single-site retrospective study

Aim

The quick sequential organ failure assessment (qSOFA) score, shock index (SI), and systemic inflammatory response syndrome (SIRS) criteria are simple indicators for the mortality of patients in the emergency department (ED). These simple indicators using only vital signs might be more useful in prehospital care than in the ED due to their quick calculation. However, these indicators have not been compared in prehospital settings. The aim of the present study is to compare these indicators measured in prehospital care and verify whether the qSOFA score is useful for prehospital triage.

Methods

We undertook a single‐site retrospective study on patients transferred by ambulance to the Kumamoto Medical Center ED (Kumamoto, Japan) between January 2015 and December 2016. We compared areas under the receiver operating characteristic (AUROC) curves of the qSOFA score, SI, and SIRS criteria measured in prehospital care. We also carried out sensitivity and specificity analyses using the Youden index.

Results

A total of 4,827 patients were included in the present study. The AUROC (95% confidence interval) of the qSOFA score for in‐hospital mortality was 0.64 (0.61–0.67), which was significantly higher than those of the SIRS criteria (0.59 [0.56–0.62]) and SI (0.58 [0.54–0.62]). According to the optimal cut‐off values (qSOFA ≥ 2) decided on as the Youden index, the sensitivity of the qSOFA score was 52.3% and its specificity was 69.9%.

Conclusions

The qSOFA score had the highest AUROC among three indicators. However, it might not be practical in actual prehospital triage due to its low sensitivity.

Shock index and modified shock index are predictors of long-term mortality not only in STEMI but also in NSTEMI patients

BACKGROUND

Shock index (SI) and modified shock index (mSI) are useful instruments for early risk stratification in acute myocardial infarction (AMI) patients. They are strong predictors for short-term mortality. Nevertheless, the association between SI or mSI and long-term mortality in AMI patients has not yet been sufficiently examined.

MATERIAL AND METHODS

For this study, a total of 10,174 patients with AMI was included. All cases were prospectively recorded by the population-based Augsburg Myocardial Infarction Registry from 2000 until 2017. Endpoint was all-cause mortality with a median observational time of 6.5 years [IQR: 3.5-7.4]. Using ROC analysis and calculating Youden-Index, the sample was dichotomized into a low and a high SI and mSI group, respectively. Moreover, multivariable adjusted COX regression models were calculated. All analyses were performed for the total sample as well as for STEMI and NSTEMI cases separately.

RESULTS

Optimal cut-off values were 0.580 for SI and 0.852 for mSI (total sample). AUC values were 0.6382 (95% CI: 0.6223-0.6549) for SI and 0.6552 (95% CI: 0.6397-0.6713) for mSI. Fully adjusted COX regression models revealed significantly higher long-term mortality for patients with high SI and high mSI compared to patients with low indices (high SI HR: 1.42 [1.32-1.52], high mSI HR: 1.46 [1.36-1.57]). Furthermore, the predictive ability was slightly better for mSI compared to SI and more reliable in NSTEMI cases compared to STEMI cases (for SI and mSI).

CONCLUSION

High SI and mSI are useful tools for early risk stratification including long-term outcome especially in NSTEMI cases, which can help physicians to make decision on therapy. NSTEMI patients with high SI and mSI might especially benefit from immediate invasive therapy.Key messagesShock index and modified shock index are predictors of long-term mortality after acute myocardial infarction.Both indices predict long-term mortality not only for STEMI cases, but even more so for NSTEMI cases.

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.

Emergency medical services shock index is the most accurate predictor of patient outcomes after blunt torso trauma

INTRODUCTION

Shock index (SI) and delta shock index (∆SI) predict mortality and blood transfusion in trauma patients. This study aimed to evaluate the predictive ability of SI and ∆SI in a rural environment with prolonged transport times and transfers from critical access hospitals or level IV trauma centers.

METHODS

We completed a retrospective database review at an American College of Surgeons verified level 1 trauma center for 2 years. Adult subjects analyzed sustained torso trauma. Subjects with missing data or severe head trauma were excluded. For analysis, poisson regression and binomial logistic regression were used to study the effect of time in transport and SI/∆SI on resource utilization and outcomes. p < 0.05 was considered significant.

RESULTS

Complete data were available on 549 scene patients and 127 transfers. Mean Injury Severity Score was 11 (interquartile range, 9.0) for scene and 13 (interquartile range, 6.5) for transfers. Initial emergency medical services SI was the most significant predictor for blood transfusion and intensive care unit care in both scene and transferred patients (p < 0.0001) compared with trauma center arrival SI or transferring center SI. A negative ∆SI was significantly associated with the need for transfusion and the number of units transfused. Longer transport time also had a significant relationship with increasing intensive care unit length of stay. Cohorts were analyzed separately.

CONCLUSION

Providers must maintain a high level of clinical suspicion for patients who had an initially elevated SI. Emergency medical services SI was the greatest predictor of injury and need for resources. Enroute SI and ∆SI were less predictive as time from injury increased. This highlights the improvements in en route care but does not eliminate the need for high-level trauma intervention.

LEVEL OF EVIDENCE

Therapeutic/care management, level IV.

Predicting the need for blood transfusion requirement in postpartum hemorrhage

OBJECTIVE

We aimed to assess the role of lactate and hemoglobin levels as predictors for the need for blood transfusion in post-partum hemorrhage (PPH).

METHODS

A retrospective cohort study of women with PPH in a single university-affiliated tertiary medical center between August 2018 and June 2020. PPH was defined as an estimated excessive blood loss (of more than 500 ml following vaginal delivery and 1000 ml following a cesarean delivery) requiring at least one uterotonic drug and fluid resuscitation. Women were stratified by the need of requiring blood transfusion due to hemorrhage. The criteria for blood transfusion were: (1) clinically severe uncontrollable ongoing hemorrhage; (2) symptomatic anemia (maternal tachycardia >110 beats per minute, dizziness, syncope or presyncope) in the presence of Hb 7-8 g/dL^; or (3) postpartum Hb level < 7 g/dL regardless of maternal symptoms or signs of anemia. Demographic, labor characteristics as well as laboratory data were collected. For all women the Shock Index (SI: heart rate divided by systolic blood pressure) was calculated. Women without available data on immediate (more than 15 min from the bleeding initiation) hemoglobin (Hb) level and lactate concentrations were excluded.

RESULTS

Overall, out of 22,241 deliveries during the study, 94 women were included, of them 26 (23.4%) required blood transfusion. The antepartum Hb level was lower in the transfused group (11.7 ± vs 12.4 ± 1.0 re/dL, p = .01). No significant differences were found in demographic and labor characteristics. In multivariate logistic regression analysis, a lower immediate postpartum Hb and a higher SI higher were associated with blood transfusion requirement (adjusted odds ratio (aOR) 3.45 [CI] 1.82-7.69, p < .001] and aOR 1.25 [CI 1.03-1.55, p = .03], respectively). The combination of SI, immediate postpartum Hb and lactate concentration provided the best integration, with an area under the curve of 0.86, sensitivity 92.65%, specificity 61.54%, positive and negative predictive values of 86.3% and 76.2%, respectively.

CONCLUSION

The combination of SI, immediate postpartum Hb and lactate levels is a good predictor for the need of blood requirement in PPH.