Pediatric Shock Index Research Articles

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

ObjectiveThe 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. MethodsWe 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. ResultsWe 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. DiscussionWe 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.

The Shock Index among Children Presenting to the Emergency Department: Analysis of Nationally Representative Sample

BackgroundThe Shock Index (SI) is emerging as a potentially useful measure among children with injury or suspected sepsis. ObjectiveThe aim of this study was to evaluate the distribution of the SI and evaluate its association with clinical outcomes among all children presenting to the emergency department (ED). MethodsA complex survey of nonfederal U.S. ED encounters from 2016 through 2021 was analyzed. Among children, the Pediatric Age-Adjusted Shock Index (SIPA), Pediatric Shock Index (PSI), and the Temperature- and Age-Adjusted Shock Index (TAMSI) were analyzed. The association of these criteria with disposition, acuity, medication administration, diagnoses and procedures was analyzed. ResultsA survey-weighted 81.5 million ED visits were included for children aged 4–16 years and 117.2 million visits were included for children aged 1–12 years. SI could be calculated for 78.6% of patients aged 4–16 years and 57.9% of patients aged 1–12 years. An abnormal SI was present in 15.9%, 11.1%, and 31.7% when using the SIPA, PSI, and TAMSI, respectively. With all criteria, an elevated SI was associated with greater hospitalization. The SIPA and PSI were associated with triage acuity. All criteria were associated with medical interventions, including provision of IV fluids and acquisition of blood cultures. ConclusionsAn elevated SI is indicative of greater resource utilization needs among children in the ED. When using any criteria, an elevated SI was associated with clinically important outcomes. Further research is required to evaluate the distribution of the SI in children and to investigate its potential role within existing triage algorithms for children in the ED.

Pediatric Shock Index + Glasgow Coma Score Outperforms Shock Indices in Predicting ICU Admission, Ventilator Use, and Need for Early Transfusion

Pediatric Shock Index + Glasgow Coma Score Outperforms Shock Indices in Predicting ICU Admission, Ventilator Use, and Need for Early Transfusion

Derivation and validation of an improved pediatric shock index for predicting need for early intervention and outcomes in pediatric trauma.

Shock index, pediatric age adjusted (SIPA), has been widely applied in pediatric trauma but has limited precision because of the reference ranges used in its derivation. We hypothesized that a pediatric shock index (PSI) equation based on age-based vital signs would outperform SIPA. A retrospective cohort of trauma patients aged 1 to 18 years from Trauma Quality Programs - Participant Use File 2010 to 2018 was performed. A random 70% training subset was used to derive Youden index-optimizing shock index (SI) cutoffs by age for blood transfusion within 4 hours. We used linear regression to derive equations representing the PSI cutoff for children 12 years or younger and 13 years or older. For children 13 years or older, the well-established SI of 0.9 remained optimal, consistent with SIPA and other indices. For children 12 years or younger in the 30% validation subset, we compared our age-based PSI to SIPA as predictors of early transfusion, mortality, pediatric intensive care unit admission, and injury severity score of ≥25. For bedside use, a simplified "rapid" pediatric shock index (rPSI) equation was also derived and compared with SIPA. A total of 439,699 patients aged 1 to 12 years met the inclusion criteria with 2,718 (1.3% of those with available outcome data) requiring transfusion within 4 hours of presentation. In the validation set, positive predictive values for early transfusion were higher for PSI (8.3%; 95% confidence interval [CI], 7.5-9.1%) and rPSI (6.3%; 95% CI, 5.7-6.9%) than SIPA (4.3%; 95% CI, 3.9-4.7%). For early transfusion, negative predictive values for both PSI (99.3%; 95% CI, 99.2-99.3%) and rPSI (99.3%; 95% CI, 99.2-99.4%) were similar to SIPA (99.4%; 95% CI, 99.3-99.4%). We derived the PSI and rPSI for use in pediatric trauma using empiric, age-based SI cutoffs. The PSI and rPSI achieved higher positive predictive values and similar negative predictive values to SIPA in predicting the need for early blood transfusion and mortality. Prognostic/Epidemiological; level III.

Validation of the age-adjusted shock index for pediatric casualties in Iraq and Afghanistan

BackgroundPediatric casualties account for a notable proportion of encounters in the deployed setting based on the humanitarian medical care mission. Previously published data demonstrates that an age-adjust shock index may be a useful tool in predicting massive transfusion and death in children. We seek to determine if those previous findings are applicable to the deployed, combat trauma setting.MethodsWe queried the Department of Defense Trauma Registry (DODTR) for all pediatric subjects admitted to US and Coalition fixed-facility hospitals in Iraq and Afghanistan from January 2007 to January 2016. This is a secondary analysis of casualties seeking to validate previously published data using the shock index, pediatric age-adjusted. We then used previously published thresholds to determine patients outcome for validation by age grouping, 1–3 years (1.2), 4–6 years (1.2), 7–12 years (1.0), 13–17 years (0.9).ResultsFrom January 2007 through January 2016 there were 3439 pediatric casualties of which 3145 had a documented heart rate and systolic pressure. Of those 502 (16.0%) underwent massive transfusion and 226 (7.2%) died prior to hospital discharge. Receiver operating characteristic (ROC) thresholds were inconsistent across age groups ranging from 1.0 to 1.9 with generally limited area under the curve (AUC) values for both massive transfusion and death prediction characteristics. Using the previously defined thresholds for validation, we report sensitivity and specificity for the massive transfusion by age-group: 1–3 (0.73, 0.35), 4–6 (0.63, 0.60), 7–12 (0.80, 0.57), 13–17 (0.77, 0.62). For death, 1–3 (0.75, 0.34), 4–6 (0.66–0.59), 7–12 (0.64, 0.52), 13–17 (0.70, 0.57). However, negative predictive values (NPV) were generally high with all greater than 0.87.ConclusionsWithin the combat setting, the age-adjusted pediatric shock index had moderate sensitivity and relatively poor specificity for predicting massive transfusion and death. Better scoring systems are needed to predict resource needs prior to arrival, that perhaps include other physiologic metrics. We were unable to validate the previously published findings within the combat trauma population.

Comparison of Prehospital Calculated Age-Adjusted Pediatric Shock Index (SIPA) to Those Calculated in the ED for Identifying Trauma Patients That Needed the Highest-Level Activation Based on Consensus Criteria

Background: The shock index (SI) is defined as the ratio of the heart rate to systolic blood pressure and a pediatric age-adjusted SI (SIPA) is more specific than the standard adult cutoff of 0.9 in identifying the sickest children presenting to a trauma center.Goal: To utilize prehospital vital signs to calculate the SIPA score and compare them to the SIPA calculated in the trauma bay to determine if they have the same validity in identifying critically ill children as determined by the consensus based standard criteria for trauma activation.Methods: Retrospective study using a cohort of patients transferred by EMS to a free standing, urban, level one, pediatric trauma center aged 1 to 16 years inclusive, and seen between January 1, 2016 and December 31, 2017. Vital signs collected during the patch call from the EMS agency were used to calculate the EMS SIPA. The first set of vital signs collected in the trauma bay was used to calculate the ED SIPA. Patients were dichotomized to an elevated or non-elevated ED SIPA and an elevated or non-elevated EMS SIPA.Results: Our cohort consisted of 2651 patients. 546 (20.6%) patients had an elevated EMS SIPA and 438 (16.5%) had an elevated ED SIPA. When compared to their non-elevated counterparts, EMS and ED SIPA were both able to identify patients who met consensus criteria in all areas except the need for IR intervention, and unstable spinal fracture/spinal cord injury. For these criteria, the ED SIPA was better than the EMS SIPA. Sensitivity and specificity analysis reveal poor sensitivity for both measures but a high specificity for ED and EMS SIPA. Both SI and SIPA have a poor PPV but high NPV.Conclusions: This study utilized prehospital vital signs to calculate the SIPA score and compare them to the SIPA calculated in the trauma bay. Both scores had similar test metrics when based on the consensus based standard trauma criteria and could be utilized in the triage traumatic injuries.

Predictive value of the shock index (SI) compared to the age-adjusted pediatric shock index (SIPA) for identifying children that needed the highest-level trauma activation based on the presence of consensus criteria

ObjectivesIn previous studies, SIPA was shown to be better than the SI in identifying children who have an elevated ISS, required transfusion, or were at a high risk of death. No comparison has been made to the consensus-based criteria that identify patients requiring the highest-level trauma activation. The objective of this study was to determine if the SIPA was more accurate than the SI in identifying children with increased need for trauma team activation as defined by the criterion standard definition, and secondly the sensitivity and specificity of the SI and SIPA. MethodsRetrospective review of prospectively collected trauma based data. Children aged 1–17 years admitted to a pediatric level 1 trauma center between 1/1/16 and 12/31/17 and met the prehospital criteria for level 1 or 2 trauma activation were included. We evaluated the ability of SI > 0.9 at ED presentation and elevated SIPA to predict need for trauma activation based on consensus criteria. SIPA cutoffs were > 1.22 (age 4–6), >1.0 (age 7–12), and > 0.9 (age 13–17). ResultsAmong 3378 children, 1486 (44%) had an elevated SI and 590 (18%) had an elevated SIPA. There were 160 (5%) patients who met at least one consensus criterion. Broadly, sensitivity and specificity analyses reveal poor sensitivity for both SI and SIPA (59.4% versus 43.1% respectively) measures but a moderate specificity for SIPA (83.8%). Both SI and SIPA have a poor PPV (6.4% versus 11.7%) but high NPV (96.6% versus 96.7%). Overall, SIPA has higher accuracy than SI in predicting consensus criteria 82% versus 57%). ConclusionSIPA is more accurate than the SI in identifying children who meet a consensus criterion defining the need for highest-level trauma activation. The low PPV and sensitivity suggest that SIPA alone, while somewhat less likely to lead to overtriage than SI is not ideal for ruling in the need for level one resources as defined by the consensus criteria.Prognosis study, retrospective. Level of EvidenceLevel II.

An unambiguous definition of pediatric hypotension is still lacking: Gaps between two percentile-based definitions and Pediatric Advanced Life Support/Advanced Trauma Life Support guidelines.

Data are lacking to provide cutoffs for hypotension in children based on outcome studies and Pediatric Advanced Life Support (PALS), and Advanced Trauma Life Support (ATLS) definitions are based on normal populations. The goal of this study was to compare different normal population based cutoffs including fifth percentile of systolic blood pressure (P5-SBP) in children and adolescents from the German Health Examination Survey for Children and Adolescents (KiGGS), US population data (Fourth Report), and cutoffs from PALS and ATLS guidelines. Fifth percentile of systolic blood pressure according to age, sex, and height was modeled based on standardized resting oscillometric BP measurements (12,199 children aged 3-17 years) from KiGGS 2003-2006. In addition, we applied the age-adjusted pediatric shock index in the KiGGS study. The KiGGS P5-SBP was on average 7 mm Hg higher than Fourth Report P5-SBP (5-10 mm Hg depending on age-sex group). For children aged 3 to 9 years, KIGGS P5-SBP at median height follows the formula 82 mm Hg + age; for age 10 to 17 years, the increase was not linear and is presented in a simplified table. Pediatric Advanced Life Support/ATLS thresholds were between KiGGS and Fourth Report until age of 11 years. The adult threshold of 90 mm Hg was reached by KiGGS P5-SBP median height at 8 years, PALS/ATLS at age of 10 years, and Fourth Report P5-SBP at 12 years. The pediatric shock index, which is supposed to identify severely injured children, was exceeded by 2.3% nonacutely ill KiGGS participants. Our study shows that percentile cutoffs vary by reference population. The 90 mm Hg cutoff for adolescents targets only those in the less than 1% of the low SBP range and represents an undertriage compared with P5 at younger ages according to both KiGGS and Fourth Report. Finally, current pediatric shock index cutoffs when applied to a healthy cohort lead to a relevant percentage of false positives. Epidemiologic/prognostic, level III.

Prospective validation of the shock index pediatric-adjusted (SIPA) in blunt liver and spleen trauma: An ATOMAC + study

BackgroundAge-adjusted pediatric shock index (SIPA) does not require knowledge of age-adjusted blood pressure norms, yet correlates with mortality, serious injury, and need for transfusion in trauma. No prospective studies support its validity. MethodsA multicenter prospective observational study of patients 4–16years presenting April 2013–January 2016 with blunt liver and/or spleen injury (BLSI). SIPA (maximum heart rate/minimum systolic blood pressure) thresholds of >1.22, >1.0, and >0.9 in the emergency department were used for 4–6, 7–12 and 13–16year-olds, respectively. Patients with ISS ≤15 were excluded to conform to the original paper. Discrimination outcomes were compared between SIPA and shock index (SI). ResultsOf 1008 patients, 386 met inclusion. SI was elevated in 321, and SIPA elevated in 282. The percentage of patients with elevated index (SI or SIPA) and blood transfusion within 24 hours (30% vs 34%), BLSI grade ≥3 requiring transfusion (28% vs 32%), operative intervention (14% vs 16%) and ICU admission (64% vs 67%) was higher in the SIPA group. ConclusionSIPA was validated in this multi-institutional prospective study and identified a higher percentage of children requiring additional resources than SI in BLSI patients. SIPA may be useful for determining necessary resources for injured patients with BLSI. Level of evidenceLevel II prognosis.