Planning for inpatient care requires a keen understanding of inpatient utilization by service line. This study was undertaken to determine the overall inpatient utilization rates in the state of Arizona, further stratified by service line and age group. We also analyzed utilization differences in the key geographies of Pima County, Maricopa County, and the Rest of Arizona while quantifying the importance of the Emergency Department (ED) relative to inpatient discharges by service line.
The answers to these questions provide Arizona health care planners and administrators insight into the demand for care, how each specialty makes up that demand, demand variation by age and geography, and the varied importance of the ED to different service lines. For those outside Arizona, these data provide a baseline for comparison as well as a methodology that can be reproduced in other geographies.
- Arizona’s overall IP utilization rate across all service lines is 467.0 bed days of care per thousand. This total utilization is made up of a Medicine bed days of care utilization rate at 190.9 (41% of total) followed by Surgery at 132.3 (28%), Mental Health and Substance Abuse at 76.5 (16%) and Maternal / Child Health at 67.2 (14%).
- Overall utilization rates trend up with age but vary widely by service line: Medicine and Surgery utilization rates trend up with age, more than doubling from the 45-64 age group to the 65+ age group; Mental Health & Substance Abuse peak in the 18-44 age group and decline thereafter; Not surprisingly, Maternal / Child Health peaks earlier, with Obstetrics reaching maximum utilization in the 18-44 age group.
- The 65+ age group comprises only 16.6% of the Arizona population but accounts for 36.7% of total bed days of care (BDOC). At the other end of the age spectrum, the pediatric population comprises 23.4% of the Arizona population but accounts for only 15.3% of BDOC.
- Geographically, there is relatively little difference in utilization rates between Maricopa and Pima counties, both of which consist of large metropolitan areas with ample access to care. The Rest of Arizona has utilization rates 15% lower than Maricopa and Pima counties, likely due to lower proximity and more difficult access to care.
The overall Arizona state discharge rate is 88.3 (per 1,000) across all service lines with an average length of stay (ALOS) of 4.6 days. The ED plays a vital gatekeeper role for IP services, with 50.8% of all IP discharges initially admitted through the ED. However, the ED’s contribution to IP discharges varies widely by service line, ranging from 7.1% for Maternal / Child Health to 84.7% for Medicine.
By Donovan Gow, Phyllis Klawsky and Garrett Abeln | August 2020