Predictors of respiratory function deterioration after transfer of critically ill patients

Objectives: Critically ill patients are often transferred due to the growin g number of diagnostic procedures required to be performed outside the inte nsive care unit. These transfers have proved to be very critical. The aim o f this study was to evaluate predictors for the deterioration of respirator y function in critically ill patients after transfer. Design: prospective, clinical, observational study. Setting: 1800-bed university teaching hospital. Subjects: 98 mechanically ventilated patients were investigated during tran sfer. Measurement and main results: Before transfer, all patients were classified according to the Acute Physiology and Chronic Health Evaluation (APACHE) I I score and the Therapeutic Intervention :Scoring System (TISS). Haemodynam ics and arterial blood gases were measured at 11 different times. Arterial oxygen tension (PaO2) fractional inspired oxygen (FIO2), PaO2/FIO2 ratio lo west PaO2/FIO2 ratio, minimal PaO2 and maximal FIO2 APACHE II score, TISS b efore transfer age and duration of transfer were analysed as potential pred ictors for deterioration of respiratory function after transfer. Variables were analysed using Classification and Regression Trees and Clustering by R esponse. In 54 transports (55 %) there was a decrease in the PaO2/FIO2 rati o, and a decrease of more than 20 % from baseline was noted in 23 of the tr ansferred patients (24 %). Age > 43 years and FIO2 > 0.5 were identified as predictors for respiratory deterioration. Conclusions: Our predictors were able to indicate deterioration after trans fer correctly in 20 of 22 patients (91 %), combined with a false-positive r ate in 17 of 49 (35 %).