Early recognition and treatment of shock and hemodynamic instability plays an important role in the management of patients admitted to PICU. In our study, we compared Shock Index (SI), Modified Shock Index (MSI) and Shock Index Pediatric age-Adjusted (SIPA) for triaging and treating children admitted to PICU. All the three indices were compared to determine which index of the three can be used as a more effective tool for early prediction of mortality and length of PICU stay.
In a study done by Kim SY et al., SI, MSI, and age multiplied SI were compared [13]. Study group was categorized into stable and unstable groups according to indices on admission to emergency department. Study included a total of 45880 cases, 97.8% of cases had SI < 1 and 2.2% of cases had SI ≥ 1. In hospitalized patients, 98.2% of survivors and 63.4% of non-survivors had SI of < 1. Similarly, in emergency department 99.1% of survivors and 43.9% of non-survivors had SI < 1.
In our study, out of 235 children, average LOS was 5 days with mortality rate of 11.48%. Sepsis, diabetic keto acidosis and pneumonia consisted majority of cases. Among 235 cases 38% had SI of ≤ 0.7 with mortality of 9%. In the remaining 62% of total cases with SI > 0.7, about 14% of patients expired. In the age group of 4 to 6 years, 40 cases (38 %) had SI value of ≤ 0.7 of which 95% of cases survived. Similarly, 64 cases (61.5%) had SI of > 0.7, out of which 56 cases survived (87.5%) and 12.5% of cases died. Among children aged between 7 and 12 years, 38.3% of cases had SI of ≤ 0.7 and 14.3% of cases died. 61.7% had SI value of > 0.7 and 84.44% survived. A total of 58 cases were aged between 13 and 16 years. 37.9% of cases had SI of ≤ 0.7, of which 95.4% survived. Sixty-two percent of cases had SI > 0.7, of which 86% of patients survived and 14% died as summarized in Table 4.
In another study by Rassameehiran S et al. [14], on utility of shock index for risk stratification in patients with acute upper gastrointestinal (GI) bleeding, a total of 214 admissions among all age groups with mean age of 59 ± 15.9 years, and mean shock index of 0.78 ± 0.21 was found. It was found that SI is good tool with potential for short-term adverse outcomes when present with upper GI bleeding.
In this study of 235 children, patients were grouped according MSI as > 1.3 or ≤ 1.3. Overall, those with MSI ≤ 1.3 had mortality of 6.3% and that of MSI > 1.3 was 14.8%. In 4–6 years age group, out of 94 cases, 55.5% had MSI of ≤ 1.3 and 4.5% of them expired. 44.5% of cases had MSI > 1.3 with survival of 81%. Among children of 7–12 years age, 51.6% had MSI of ≤ 1.3 and 94% survived. While 44 cases had MSI > 1.3 out of which 28.2% died. In children of 13–16 years age, 59.6% had MSI of ≤ 1.3 with mortality of 3.2%, 23% of cases with MSI of > 1.3 expired.
In the study done by Kim SY et al. [13], out of 45,880 cases, 97.3% had MSI of < 1.3 and 2.2% had MSI of ≥ 1.3. 97.8% of survivors and 61.4% of non-survivors had MSI < 1.3.
In a study of 18,478 adults, conducted by Sotello et al. [4], 97.1% of cases were alive before discharge and had MSI ≤ 1.3. The observed mortality of patients with an MSI ≤ 1.3 was 2.9% and the mortality of those with an MSI > 1.3 was 10.3%.
From our study as specified in Table 5, on age adjusting SI for children between age 4 and 6 years, 97.7% of cases who had a SIPA score of ≤ 1.22 survived with median hospital stay of 4 days. 84.7% patients with SIPA > 1.22 survived with median hospital stay of 4 days. Among children aged between 7 and 12 years, 94% of cases with SIPA ≤ 1 survived with median length of hospital stay of 3 days. However, 76.9% of patients with SIPA > 1 survived with median length of hospital stay of 5 days. In 13–16 years age group, 32 had SIPA ≤ 0.9 of which 96.5% of cases survived and 3.5% had expired. Out of 26 cases with SIPA > 0.9, 80.7% survived with median hospital stay of 6 days.
In study done by Acker S N, et al. [9], Shock Index Pediatric age-Adjusted (SIPA) was more accurate than age-adjusted hypotension for trauma team activation; children of ages 4–16 years were included in the study. Inclusion criteria for trauma team activation included blood transfusion, emergency operation, or endotracheal intubation. A total of 559 cases were included. Thirty percent of patients who required operative intervention showed increased SIPA over time. Similarly, 40% of children on mechanical ventilator had increase in SIPA score. In the same line, 53% of children requiring blood transfusion showed progressive increase in SIPA score. It was demonstrated that SIPA is superior to age-adjusted hypotension to identify injured children who required trauma team activation.
In another study done by Kim SY et al. [13], age-adjusted SI was taken in total of 45,880 cases, majority of cases (78.1%) had age-adjusted SI < 50. Among admitted cases, 78.7% of survivors had age-adjusted SI of < 50 and 69.4% of non-survivors had age-adjusted SI of ≥ 50. Similarly, at emergency department, 81.2% of survivors had age-adjusted SI of < 50 and 83.1% of non-survivors had age-adjusted SI ≥ 50. In a similar study done by Sotello et al. [4], among 18,478 adult case, 97.5% cases were alive at discharge with age-adjusted SI ≤ 50 and 10% of cases with age-adjusted SI > 50 expired.