Does acuity matter?--Optimal timing of tracheostomy stratified by injury severity.

BACKGROUND A number of conflicting studies have been conducted to analyze the relationship between the timing of tracheostomy and mortality, intensive care unit (ICU) length of stay (LOS), hospital LOS, and the incidence of pneumonia. In contrast to previous studies, this relationship was investigated in the context of expected survival based on probability of survival (Ps) greater than 25%. METHODS Trauma patients were screened using a statewide registry during a 5-year period (January 2001 to December 2005). Burn patients, transfer patients, permanent tracheostomies, and patients who underwent multiple surgical airways were excluded from the study. Data were collected on patient demographics, Trauma and Injury Severity Score, days to tracheostomy, mortality, ICU LOS, total ventilator days, pneumonia, and hospital LOS. STATISTICAL ANALYSES log-linear modeling, chi2, p < 0.05. RESULTS A total of 125,533 trauma patients were analyzed. Out of these, 82,148 patients met inclusion criteria and had complete data for analysis. There were 6,880 patients intubated at the scene, during transport, or at admission to the emergency department, with 685 receiving a temporary tracheostomy. There was a significantly higher mortality rate (48.9%) associated with patients with low Ps (<0.25) receiving early tracheostomy (ET), <4 days. Among high-Ps patients, the ET group demonstrated reduced ICU LOS, total ventilator days, pneumonia, and hospital LOS (p < 0.05). CONCLUSION ET in patients with low Ps may not be beneficial given the substantially high mortality rate before post injury day 4. However, ET in high-Ps patients reduces ICU and hospital LOS, total ventilator days, and the incidence of pneumonia. This suggests an increased benefit in ET to trauma patients with high Ps.