The Pediatric Hybrid Observation Unit: An Analysis of 6477 Consecutive Patient Encounters
Authors: Zebrack Michelle , Kadish Howard , Nelson Douglas 
Published: May 2005

Objectives.Pediatric observation units (OUs) are becoming more common in hospitals throughout the United States, providing physicians with a new disposition option for children who are judged to be too ill for home management. Some OUs function as “hybrid” units, serving both acutely ill and injured observation patients as well as scheduled elective procedure patients. How best to utilize this new resource is not yet defined. We studied the utilization of our pediatric hybrid OU during the first 2 years of operation to determine (1) the spectrum and frequency of diagnoses treated, (2) diagnoses and procedures most (and least) likely to attain discharge successfully within 24 hours, and (3) whether age was associated with inability to be discharged from the OU within 24 hours.
Methods.The study setting was a 20-bed hybrid OU located in a pediatric tertiary care hospital in Salt Lake City, Utah. The records of all patients admitted during the first 2 years of OU operation, from August 1999 through July 2001, were examined retrospectively.
Results.There were 6477 OU admissions: 4189 (65%) for acutely ill and injured observation patients and 2288 (35%) for scheduled elective procedure patients. For the observation patients, median age was 2.5 years and median length of stay was 15.5 hours. Common admission diagnoses in these patients included enteritis/dehydration (n = 722), orthopedic injuries (n = 362), asthma (n = 327), closed head injury (n = 289), urgent transfusion/infusion (n = 221), bronchiolitis (n = 212), croup (n = 207), abdominal pain (n = 199), cellulitis (n = 177), and nonfebrile seizure (n = 98). Overall, 15% of observation patients required subsequent inpatient admission for &gt;24-hour stay. Observation diagnoses that were most likely to require inpatient admission were hematochezia (60%), viral pneumonia (46%), and bronchiolitis (43%). We demonstrated successful OU discharge rates (&gt;85%) for several diagnoses not commonly reported: neonatal hyperbilirubinemia, aseptic meningitis, and diabetic ketoacidosis in the patient with known diabetes. Among the scheduled elective procedure patients, median age was 5.0 years and median length of stay was 3.0 hours. Only 1% of these patients required subsequent inpatient admission. In both populations, age ≤30 days was associated with increased need for inpatient admission, with a relative risk of 1.9 (95% confidence interval: 1.4–2.6) among the observation patients and 13.9 (95% confidence interval: 3.0–65.0) among scheduled procedure patients.
Conclusion.Our pediatric hybrid OU played an important role in the treatment of children who were admitted for observation as a result of acute illness or injury, as well as children who required scheduled procedures. For both patient types, we identified diagnoses that are most and least likely to attain successful discharge within 24 hours. The majority (85%) of observation patients were discharged successfully within 24 hours. Successful discharge rates for diagnoses that are not commonly managed in other pediatric OUs were reported. We identified certain age groups within selected diagnoses that may not have been appropriate for the OU.