Cleveland Clinic Children's Outcomes

An unplanned extubation is defined as dislodgement or removal of the endotracheal tube from the trachea in a patient receiving invasive mechanical ventilation at a time that was not specifically intended or ordered by a physician. ¹

¹Merkel L, Beers K, Lewis MM, Stauffer J, Mujsce DJ, Kresch MJ. Reducing Unplanned Extubations in the NICU. Pediatrics. 2014;133(5). doi:10.1542/peds.2013-3334.

Standardized mortality ratio (SMR) is the ratio of actual deaths to predicted deaths. The number of predicted deaths is calculated using the Pediatric Risk of Mortality III (PRISM III) score or the Pediatric Index of Mortality 3 (PIM 3) score. These are physiology-based mortality risk tools widely used to predict the intensive care outcomes of children.

An SMR of 1 indicates that observed mortality is equal to predicted mortality. An SMR > 1 suggests that more patients died than predicted using PRISM III or PIM 3, whereas an SMR < 1 indicates that fewer patients than predicted died. PIM 3 uses physiologic data from the first hour of admission to the pediatric intensive care unit (PICU). However, data from the immediate pre-ICU time frame may be used if the intensivist treated the patient before arrival to the PICU. Other variables used to calculate the PIM 3 include: the use of mechanical ventilation, whether the admission was elective, whether the patient was in the PICU primarily for postoperative recovery, the use of cardiac bypass, and the presence of certain high- and low-risk diagnoses.

PRISM III uses data from the first 12 hours of admission to the PICU to predict risk of mortality, using the most extreme values documented in the data collection time frame. Compared with PRISM III, PIM 3 is less likely to be biased by the quality of treatment after admission to the PICU, but may be subject to bias from different intervention thresholds. Utilizing PRISM III as an indicator of severity of illness, standardized length-of-stay ratios are calculated by comparing the observed with the expected length of stay.