Prone Kinetic Therapy (PKT) during ventilation for Acute Respiratory Distress Syndrome (ARDS) has been shown to reduce patient morbidity. Early tracheostomy in ARDS has further been shown to reduce ICU resources and lower patient comorbidity. We undertook a dual-center retrospective review to predict the earliest window for tracheostomy during the application of PKT. We hypothesized that while applying PKT to ARDS patients, the change in ABG data over time may signal the earliest tracheostomy window.
Of 37 sequential PKT patients at Banner Desert Medical Center, Mesa, AZ (Jan, 2004 to Dec, 2005, Margolin/Lauzon) and 14 at Methodist Hospital, Indianapolis, IN (Mar, 2004 to Oct, 2004, Powers), 22 and 11 patients respectively met the inclusion criteria. ABG data, in relationship to the application of PKT, was paired with ventilator liberation status at time of ICU discharge (downgrade, transfer or death). Patients were excluded from evaluation if ABG data was absent, PKT was ceased before day three, or patients only received Kinetic Therapy without proning, Daily median P/F ratios and changes in pCO2 were calculated. Baseline values were the median of all values in the 12 hours proceeding start of PKT (Figure 1). Daily percent changes were divided by the patient's age and the results were transformed by log function to generate a normal distribution. A logistic regression was then calculated.
We found that the P/F data predicted ventilator liberation by PKT day #3 in the following formula[(1=yes) = 2.1 − 1.7[log(day3%/Age)], p<0.05. (Figure 2). The line generated maintained observational strength out to 5 days of PKT. We found changes in PaCO2 could not predict utility in the timing of early tracheostomy.
These data suggest a reliable indicator may exist for the optimal timing of tracheostomies in ARDS patients exposed to PKT base upon their P/F ratio response.
Translation of this model to the bedside could potentially aid in optimizing tracheostomy placement and ultimately reducing hospital-acquired morbidity and ICU-related expenditures.
Gregory Margolin, Employee George Hutchinson, PhD is an employee of KCI.; No Product/Research Disclosure Information