Resource Utilization of Adults Admitted to a Large Urban Hospital With Community-Acquired Pneumonia Caused by Streptococcus pneumoniae: Recommendation
The present results do confirm findings from other studies demonstrating that hospital bed costs are the major contributor to total costs for CAP. In the study by Klepser et al, room costs accounted for 34% of total hospital costs and nursing costs accounted for 37%. Although we were not able to separate nursing costs from that of room costs in our study, our hospital bed costs accounted for both direct and indirect fixed costs. When added together, the percentage of resources dedicated to room and nursing was similar with our reported hospital bed cost percentage of 55.6%. Likewise, in a separate study to assess resource utilization in the treatment of CAP, Orrick and colleagues found median costs to be $2,430 for their population, with hospital room costs constituting 83.7% of total costs, followed by antibiotic (4.6%), radiology (2.6%), and respiratory care (0.9%) costs. It is not surprising then that admission to an ICU in our study was significantly associated with an increased cost and length of stay, as daily bed cost and total length of stay (11 days vs 5 days, p < 0.001) were both greater for patients in the ICU compared with a normal hospital bed. Importantly, these data taken together confirm that antibiotic costs account for only a small percentage (< 5%) of total costs in the treatment of hospitalized patients with CAP; moreover, any efforts to reduce total or ICU length of stay, such as IV-to-oral transition or clinical pathways, will have the most profound effect on reducing the economic burden of CAP.
The only variable that was significantly different between the susceptible and nonsusceptible groups in this study was the presence of bacteremia. In our analysis, 48% of patients infected with penicillin-susceptible S pneumoniae were also bacteremic, compared with 25% of patients with nonsusceptible isolates (p = 0.012). These results are consistent with numerous other reports in which invasive disease was more common among susceptible pneumococci. This is probably related to organism serotype, with certain serotypes commonly more susceptible than others, but also more virulent. We were unable to confirm this because we did not have access to the S pneumoniae isolates in our study to perform serotyping.
One interesting and perhaps still controversial observation in our study was the significance of the variable we defined as unexpected delayed discharge in predicting total costs and increased length of stay. Although difficult, it was our intent to characterize a measure of prolonged and unnecessary observation. We used clinical criteria (normalization of temperature and WBC) as well as transition to oral antibiotic therapy to determine whether the physicians in our hospital might by using unnecessarily longer observation periods and not discharging patients when they were stable.