The availability and use of out-of-hospital physiologic information to identify high-risk injured children in a multisite, population-based cohort

Abstract

Objective: The validity of using adult physiologic criteria to triage injured children in the out-of-hospital setting remains unproven. Among children meeting adult field physiologic criteria, we assessed the availability of physiologic information, the incidence of death or prolonged hospitalization, and whether age-specific criteria would improve the specificity of the physiologic triage step.

Methods: We analyzed a prospective, out-of-hospital cohort of injured children aged < or =14 years collected from December 2005 through February 2007 by 237 emergency medical services (EMS) agencies transporting to 207 acute care hospitals (trauma and nontrauma centers) in 11 sites across the United States and Canada. Inclusion criteria were standard adult physiologic values: systolic blood pressure (SBP) < or =90 mmHg, respiratory rate < 10 or > 29 breaths/min, Glasgow Coma Scale (GCS) score < or =12, and field intubation attempt. Seven physiologic variables (including age-specific values) and three demographic and mechanism variables were included in the analysis. "High-risk" children included those who died (field or in-hospital) or were hospitalized > 2 days. The decision tree was derived and validated using binary recursive partitioning.

Results: Nine hundred fifty-five children were included in the analysis, of whom 62 (6.5%) died and 117 (12.3%) were hospitalized > 2 days. Missing values were common, ranging from 6% (respiratory rate) to 53% (pulse oximetry), and were associated with younger age and high-risk outcome. The final decision rule included four variables (assisted ventilation, GCS score < 11, pulse oximetry < 95%, and SBP > 96 mmHg), which demonstrated improved specificity (71.7% [95% confidence interval (CI) 66.7-76.6%]) at the expense of missing high-risk children (sensitivity 76.5% [95% CI 66.4-86.6%]).

Conclusions: The incidence of high-risk injured children meeting adult physiologic criteria is relatively low and the findings from this sample do not support using age-specific values to better identify such children. However, the amount and pattern of missing data may compromise the value and practical use of field physiologic information in pediatric triage.

FIGURE 1

Length-of-stay distribution among survivors (n = 893).

FIGURE 2

The proportion of missing values for out-of-hospital systolic blood pressure among injured children, by age group and outcome (N = 955).High-risk = mortality (field or in-hospital) or length of hospital stay >2 days; low-risk = survival with 0–2-day length of stay.

FIGURE 3

The proportion of missing values for out-of-hospital respiratory rate among injured children, by age group and outcome (N = 955). High-risk = mortality (field or in-hospital) or length of hospital stay >2 days; low-risk = survival with 0–2-day length of stay.

FIGURE 4

The proportion of missing values for out-of-hospital Glasgow Coma Scale (GCS) score among injured children, by age group and outcome (N = 955). High-risk = mortality (field or in-hospital) or length of hospital stay >2 days; low-risk = survival with 0–2-day length of stay.

FIGURE 5

Physiologic decision rule to identify high-risk injured children (mortality or length of hospital stay >2 days) meeting American College of Surgeons Committee on Trauma (ACSCOT) step 1 criteria (validation set, n = 382). Event = mortality (either field-based after resuscitative efforts or in-hospital) or hospital length of stay greater than 2 days. Non-event = survival with hospital length of stay 0–2 days. Predictor variables considered in developing this decision tree included systolic blood pressure (SBP) (mmHg), respiratory rate (breaths/min), Glasgow Coma Scale (GCS) score, pulse rate (beats/min), pulse oximetry (percentage oxyhemoglobin saturation), shock index (pulse rate/SBP), ventilatory support (bag–valve–mask or advanced airway), and age.