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

J Intensive Care Med. 2020 Oct;35(10):984-991. doi: 10.1177/0885066618802779. Epub 2018 Oct 2.

Abstract

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.

Keywords: children; cut-off; mortality; sepsis; septic shock; shock index.

Publication types

  • Evaluation Study

MeSH terms

  • Adolescent
  • Age Factors
  • Biomarkers / analysis
  • Child
  • Child, Preschool
  • Female
  • Humans
  • Infant
  • Infant, Newborn
  • Male
  • Predictive Value of Tests
  • Prognosis
  • Prospective Studies
  • ROC Curve
  • Reference Values
  • Risk Assessment
  • Risk Factors
  • Sensitivity and Specificity
  • Sepsis / diagnosis*
  • Sepsis / mortality*
  • Severity of Illness Index*
  • Shock, Septic / diagnosis*
  • Shock, Septic / mortality*
  • Time Factors

Substances

  • Biomarkers