Statistical analysis:
Appropriate data entry and statistical analysis was performed on Microsoft Excel 2010 (Microsoft, Redmond, WA) and SPSS software version 20 (SPSS, Inc, Chicago, IL). Descriptive statistics [number (percentages) and median (interquartile range, IQR)] was used for baseline variables. The infants admitted to PICU were compared with those who do not required PICU admission by using Chi square test for categorical variables and Mann Whitney U test for continuous variables. Multivariate analysis was done to find out independent predictors of PICU admission. All tests were two-tailed and p value <0.05 was taken as significant.