The Science Journal of the American Association for Respiratory Care

2008 OPEN FORUM Abstracts


Carla Wollens1, Jorge A. Guzman1, Robert Chatburn1

Background: Available data do not permit identification of a minimum set of necessary and sufficient criteria for determining readiness for weaning (wean screen WS), successful spontaneous breathing trials (SBT) or readiness for extubation (extubation screen ES). The purpose of this study was to provide benchmarking data for one set of criteria used in an academic, tertiary care medical ICU.

Methods: A ventilator management protocol was implemented describing 4 phases of ventilatory support: (1) initial stabilization on full support; (2) daily assessment until WS met; (3) weaning by daily 60 minute SBT alternated with full support; (4) extubation. Phase criteria are shown in the figure. Duration of ventilation = date extubated - date intubated, stabilization = date first WS - date intubated. Wean assessment = date first passed WS - date first WS. Weaning = date SBT passed - date passed WS. Extubation assessment = date ES passed - date SBT passed. Extubation delay = date extubated - date ES passed. All patients requiring mechanical ventilation between 1/1/8 and 1/6/8 were included. Patients transferred out of the MICU before extubation were excluded.

Results: Data from 57 patients were evaluated. Major outcomes expressed as median (range) in days: duration of ventilation = 4 (0.42 - 31), stabilization = 1.2 (0.16 - 2.6), wean assessment = 1 (0 - 6.14), weaning = 0.25 (0 - 10.17), extubation assessment = 0.04 (0 - 29.74), extubation delay = 0.03 (0 - 24). Seventy percent of patients failed the first WS; 25% failed first SBT; 30% failed first ES. One patient required reintubation within 24 hours. Criteria failure data are shown in the figure.

Conclusion: Duration of ventilation might be reduced by loosing or eliminating WS criteria FiO2 and PEEP and SBT criterion respiratory rate. Assessment time might be saved by eliminating WS criteria PaO2, HR, BP, and temperature and eliminating SBT criteria BP and blood gases, as these variables rarely led to failure. These assumptions should be tested to help define minimum sets of necessary and sufficient criteria.