This is a classic paper from 2000 (now available free!), published by Rosenberg and Watts of the University of Michigan, in the journal Chest. With the recent talk about a potential new JCAHO National Patient Safety Goal for Medical Emergency Teams, and other techniques like house-wide monitoring to avoid ICU readmissions, I thought it would be a good time to look at what we're trying to avoid.

In this study, Rosenberg and Watts reviewed primary articles focusing on ICU readmission or ICU outcomes from January 1966 to June 1999. Eight primary studies of ICU readmission and eight multi-institutional ICU outcome studies that reported ICU readmission rates were included. Here's what the data showed:

  • The average ICU readmission rate of 7% (range,4 to 14%) has remained relatively unchanged in both North America and Europe.
  • Respiratory and cardiac conditions were the most common(30 to 70%) precipitating cause of ICU readmission.
  • Patients readmittedto ICUs had average hospital stays at least twice as long as non-readmitted patients.
  • Hospital death rates were 2- to 10-times higher for readmitted patients than for those who survived an ICU admission and were never readmitted.
  • Predictors of ICU readmission have been neither well studied nor reproducible. Unstable vital signs, especially respiratory and heart rate abnormalities, and the presence of poor pulmonary function at time of ICU discharge appear to be the most consistent predictors of ICU readmission.
  • There were no consistent data supporting the use of readmission rates as a measure of quality of care.

The most common reasons for ICU readmission were pulmonary problems, including hypoxia and inadequate pulmonary toilet. Neurologic impairment, medication toxicities, and postoperative monitoring accounted for 20% of the aggregate causes for readmission. A variety of cardiac conditions — arrhythmia, congestive heart failure and cardiac arrest, followed by upper-GI bleeding, and neurologic impairments—were also common causes of ICU readmission. Two studies that included cardiac ICUs reported a predominance of cardiac-related readmissions - unstable angina or arrhythmias caused 49% of the readmissions, whereas congestive heart failure was the most common nonoperative cause of ICU readmission in the study by Cooper et al (7.6%). Among the reasons for ICU readmission unrelated to the patient’s diagnosis on initial admission were new cardiac complaints, medication toxicities, and pulmonary disorders involving hypoxia, especially pneumonia, or ventilatory failure.