The weaning continuum use of Acute Physiology and Chronic Health Evaluation III, Burns Wean Assessment Program, Therapeutic Intervention Scoring System, and Wean Index scores to establish stages of weaning

Objective: To determine whether four stables of weaning (acute, prewean, we an, and outcome) could be identified by using clinical instruments designed to quantify severity of illness, patient stability, or weaning readiness, The instruments used were the Acute Physiology and Chronic Health Evaluatio n (APAGHE III), the Therapeutic Intervention Scoring System (TISS), the Bur ns Wean Assessment Program (BWAP), and the Wean Index (WI). The stages were adapted from those proposed by the American Association of Critical Care N urses Third National Study Group's Weaning Continuum Model. Design: Prospective, convenience cohort. This study was part of a larger st udy designed to test an outcomes managed approach to weaning by using an ou tcomes manager and a clinical pathway. Setting: University medical intensive care unit. Patients: Adult patients requiring mechanical ventilation >3 days admitted to the medical intensive care unit between November 1994 and May 1995, Interventions: None. Measurements and Main Results: Scores for the APACHE III, TISS, BWAP, and W I were collected on 97 patients every other day until they weaned, were tra nsferred, or died. Outcomes described for each stage of weaning were dated on the clinical pathway when achieved, Comments about patient stability and ventilator progress also were recorded along with a subjective determinati on of the stage of weaning. We used decision rules to identify time interva ls for each stage of weaning and outcomes attained by stage. Finally, APACH E III, TISS, BWAP, and WI scores were placed in each stage by date for anal ysis. The APACHE III, TISS, and BWAP scores were able to differentiate the acute, prewean, and wean stages but not the outcome stage, Conclusions: By identifying distinct scores for each stage, we may be able to better explore appropriate interventions for the stages as well as predi ct weaning outcomes. Indices that include physiologic and respiratory facto rs can differentiate weaning stages, but respiratory factors alone cannot.