Determinants of time-to-weaning in a specialized respiratory care unit.
BACKGROUND
As the decision-making process in long-term respiratory care units often depends on time-based outcomes, we sought to identify independent predictors of time-to-weaning (TTW) in a hospital-based specialized respiratory care unit.


METHODS
Characteristics that were identified in previous studies as predictors of weaning success in ICUs and long-term ventilator units were prospectively collected on 113 consecutive admissions to our unit. TTW analyses were performed with Kaplan-Meier curves, log rank test, and Cox proportional regression.


RESULTS
The TTW was shorter in patients with static lung compliance (Cst) of > 20 mL/cm H(2)O, a normal creatinine level (0.6 to 1.4 mg/dL), a rapid shallow breathing index (RSBI) of < or = 105, intact skin, and in those patients from a surgical referral source. We found an interaction between RSBI and Cst (p = 0.02) such that patients with an RSBI of < or = 105, regardless of Cst, had a median TTW of 11 days, those with an RSBI of > 105 and a Cst of > 20 had a median TTW of 31 days, and those with an RSBI of > 105 and a Cst of < or = 20 mL/cm H(2)O had not reached a median TTW by 60 days (p = 0.007 [log rank for linear trend]). In a Cox-proportional hazard model, both this categorization model of RSBI and Cst, and renal function had a significant impact on TTW.


CONCLUSIONS
In a multivariate model incorporating the variables reviewed, only the lung parameters (RSBI combined with Cst) and renal function remained independently associated with TTW.
Aboussouan
Loutfi S
LS
Pulmonary, Critical Care and Sleep Medicine, Harper University Hospital, Wayne State University, Detroit, MI, USA. aboussl@ccf.org
Lattin
Chris D
CD
Anne
Vijay V
VV
D018806:APACHE; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003404:Creatinine / Q000097:blood; D005260:Female; D006757:Hospital Units; D006801:Humans; D008170:Lung Compliance; D008824:Michigan; D008875:Middle Aged; D015999:Multivariate Analysis; D016016:Proportional Hazards Models; D012372:ROC Curve; D015656:Respiratory Mechanics; D013997:Time Factors; D015300:Ventilator Weaning
D003404:Creatinine