Processes of care, illness severity, and outcomes in the management of community-acquired pneumonia at academic hospitals.

BACKGROUND

Prompt antibiotic administration, oxygenation measurement, and blood cultures are generally considered markers of high-quality care in the inpatient management of community-acquired pneumonia (CAP). However, few studies have examined the relationship between prompt achievement of process-of-care markers and outcomes for patients with CAP. We examined whether antibiotic administration within 8 hours of hospital arrival, a blood culture within 24 hours, an oxygenation measurement within 24 hours, or performing blood cultures before giving antibiotics was associated with the following: (1) reaching clinical stability within 48 hours of hospital admission, (2) a decreased length of hospital stay, or (3) fewer inpatient deaths.

METHODS

A retrospective medical record review identified 1062 eligible patients discharged from the hospital with a diagnosis of CAP between December 1, 1997, and February 28, 1998, among 38 US academic hospitals. We assessed the independent relationship between each process marker and the 3 clinical outcomes, controlling for the Pneumonia Severity Index on admission. We also examined the relationship of pneumonia severity on admission to process marker achievement and clinical outcomes.

RESULTS

Overall, there was no consistent or statistically significant relationship between achieving process markers and better clinical outcomes (P>.40 for all). We did observe that performing blood cultures within 24 hours was related to not achieving clinical stability within 48 hours (odds ratio, 1.62; 95% confidence interval, 1.13-2.33). However, this finding likely reflects residual confounding by severity of illness, since increasing pneumonia severity on admission was associated with blood culture performance (P =.009) and with shorter times to antibiotic administration (P =.04).

CONCLUSIONS

Achieving process-of-care markers was not associated with improved outcomes, but was related to the severity of pneumonia as assessed on admission. Our results highlight the difficulty in demonstrating a link between process-of-care markers and outcomes in observational studies of CAP. Randomized studies are needed to objectively evaluate the impact of process-of-care markers on CAP outcomes.