PRISM III Calculator


Physiologic variables are measured only in the first 4 hours of PICU care, and laboratory variables are measured in the time period from 2 hours before PICU admission through the first 4 hours. Neurologic score is calculated using GCS and Pupillary reflexes scores. Non-Neurologic is calculated from the remainder.

-Pollack MM, Dean JM, Butler J, et al: The ideal time interval for critical care severity-of-illness assessment. Pediatric Critical Care Med 2013; 14:448-453


Variable Lowest and/or Highest Measurements around PICU Admission Category Score







Systolic blood pressure      Low:   mmHg
Temperature       Low: °C                High: °C
Mental Status (glasgow coma scale)        GCS
Heart Rate      High:   beats per minute
Number of Pupils > 3mm And Fixed       
pH       Low: pH              High: pH
Total CO2       Low:   mmol/L     High:   mmol/L
Acidosis or Total CO2       calculated from lowest pH or lowest Total CO2
PCO2      High:   mmHg
Arterial PaO2      Low:   mmHg
Glucose      High:   mmol/L
Potassium      High:   mmol/L
Creatinine      High:   µmol/L
Urea      High:   mmol/L
White Blood Cells      Low:   cells/mm³
PT:      High:   seconds
PTT:      High:   seconds
Platelets      Low:  cells/mm³

The calculator tool is provided “as is” and without any warranty of any kind, express or implied.  In no event shall the University of Utah, CPCCRN, or the authors be liable for any claims, damages or other liability arising out of use of the calculator tool.

The PRISM III calculator was recently noted to have errors in its algorithm, which have been corrected as of November 11, 2019. If you used the calculator prior to this date, the results may be erroneous, depending on the values that you entered into the calculator. The flawed calculator used the HIGHEST white count instead of the LOWEST white count, and the calculator should have used the lowest platelets, but this was not possible to enter because the calculator inserted “not measured”. The ‘acidosis or total CO2’ was scored as 6 even when lowest pH and lowest total CO2 were not below the associated threshold. We apologize for any inconvenience caused by these errors.

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