Abstract
Pediatric Index of Mortality 2 (PIM-2) is one of the leading mortality scores used
in intensive care units all around the world. We assessed its validity as an outcome
predictor in a pediatric intensive care unit (PICU) of Mayo Hospital/King Edward Medical
University Lahore, Pakistan. We enrolled 154 consecutive admissions, aged 1 month
to 13 years, requiring intensive care from January to June of 2019. Patient demographics
along with PIM-2 data were collected; PIM-2 score and mortality risk was calculated;
and the outcome recorded as death or survival. The median age at admission was 0.50
years (interquartile range [IQR]: 0.24–1.78) and the median weight was 5.0 kg (IQR:
3.08–10.0) with females constituting 54%; malnutrition was also common (66%). Observed
mortality was 29.9% (46 out of 154) and expected mortality (cut-off ≥ 99.8%) was 27.9%
with a standardized mortality ratio of 1.07 (95% confidence interval [CI]: 0.79–1.41).
Sepsis was the most common diagnosis at admission (27.9%) with the highest mortality
(52.2%). Chi-square analysis revealed a sensitivity of 54.3% and a specificity of
83.3% (p-value 0.00). PIM-2 score showed acceptable discrimination between survivors and nonsurvivors
with an area under the receiver operating characteristic curve of 0.75 (95% CI: 0.67–0.84)
(p-value = 0.00); however, poor calibration according to Hosmer–Lemeshow goodness of
fit test (Chi-square = 15.80, df = 7, and p-value of 0.027 [< 0.1]), thus requiring recalibration according to local population
characteristics.
Keywords
mortality - pediatric index of mortality 2 - validity - pediatric intensive care unit
- sepsis
