Factors Associated With Long Hospital Length of Stay in Patients Receiving Warfarin After Cardiac Surgery

Abstract

Patients receiving warfarin therapy after coronary artery bypass graft (CABG) or valve surgery have longer length of stay (LOS) than those not receiving warfarin therapy. Longer LOS increases patient costs, postdischarge recovery time, and rehabilitation. It is important to identify variables of longer postoperative LOS in this patient population so that the healthcare team can develop and facilitate interventions to minimize length of hospitalization. Using a hospital registry and medical record review of cases completed in 2004, data from cardiac surgery patients having CABG and/or valve procedures and given warfarin postoperatively were analyzed based on short (<7 days, CABG; 9 days, valve procedure) and long (> or =7 days, CABG; > or =9 days, valve procedure) postoperative LOS. By groups, significant associations were assessed using chi or Fisher exact test for categorical variables and Wilcoxon 2-sample test or Student t test for continuous variables. In 82 patients (33 CABG and 49 valve +/- CABG) who were given warfarin, most demographic, medical history, postoperative complications, and use of cardiac drugs did not predict longer LOS. Longer postoperative LOS was associated with being older (mean age, 73.5 vs 68.5 years), being not married, having postoperative respiratory insufficiency, and receiving more red blood cell transfusions, all P < .05; and having more healthcare consultations, longer critical care stay, and longer time between surgery date and start of warfarin; all P < .001. Variables associated with longer LOS were nonmodifiable by nursing services and were difficult to assess preoperatively. They primarily involved intraoperative or postoperative bleeding that led to red blood cell infusion and longer critical care stays that delayed warfarin initiation. However, older age and marital status are nursing targets because they may be associated with social isolation and other psychosocial issues. Transition of care programs can be developed to promote earlier discharge.