CHICAGO — Early antibiotic therapy does not improve survival in emergency department patients with community-acquired pneumonia, suggesting that the reallocation of resources for that purpose is unnecessary, according to two studies presented at the annual meeting of the Society for Academic Emergency Medicine.
“Our results suggest that the time to antibiotics in the 0- to 24-hour range has little impact on survival from community-acquired pneumonia,” said Dr. Marie Elie and colleagues at the New Jersey Medical School, Newark.
Largely as a result of a 2004 study (Arch. Intern. Med. 2004;164:637–44), the Centers for Medicare and Medicaid Services and the Joint Commission recommend that patients with community-acquired pneumonia be given an appropriate antibiotic within 4 hours of their arrival in the emergency department.
CMS and the Joint Commission set the measure identification number for this 4-hour guideline as quality measure PN-5b.
The 2004 retrospective study had mined the medical records from a national random sample of 18,000 Medicare patients older than 65 years who were hospitalized with community-acquired pneumonia (CAP) between 1988 and 1999.
Consistent with CMS guidelines, CAP patients in the study were identified as those with a discharge diagnosis between ICD-9 (CAP) codes 480 and 486, and pneumonia diagnosed within 24 hours of ED presentation, in order to distinguish CAP from hospital-acquired pneumonia, said Dr. Elie, director of emergency critical care at New Jersey Medical School.
The study cohort, drawn from three urban New York hospitals, consisted of 4,300 patients given antibiotics within 48 hours of hospital arrival.
The overall mortality rate was 7.6%. For patients with systemic inflammatory response syndrome (SIRS) in the ED, the mortality rate was 12%; without SIRS, it was significantly lower, at 5%. In addition, there was a significant relationship between increasing Acute Physiology and Chronic Health Evaluation (APACHE) II scores and decreasing survival.
There was no statistically significant linear effect of time to antibiotics on mortality, whether time to antibiotics was examined as the only explanatory variable or after adjustment for initial APACHE II score and SIRS.
A second study determined mortality rates and geometric length of stay (GLOS) for adult ED patients admitted to Union Memorial Hospital in Baltimore with a diagnosis of pneumonia.
Mortality rates and GLOS were determined for 1,781 patients and compared annually over 3 years during 2003–2006 with expected mortality rates and expected GLOS calculated using the CareScience risk-adjustment methodology (Quovadx Inc.).
CareScience is an Internet-based risk-adjustment program in which about 150 U.S. hospitals participate; each submitted information about resource use, pharmacy, radiology, device, procedure, discharge diagnosis, and demographics, said Dr. William Frohna, chief of emergency medicine at Union Memorial Hospital.
The retrospective, observational study used patient selection criteria of the Joint Commission's National Hospital Quality Measures, hospital records, and the CareScience database to determine outcomes at a time when performance improvement efforts significantly cut the time to antibiotics in the ED.
In the first of the 3 years, 67% of about 600 patients discharged from the Union Memorial Hospital ED with a diagnosis of pneumonia received an antibiotic within 4 hours. In the second and third years, the percentage rose to 77% and 91%, respectively, Dr. Frohna said.
“Our mortality went from 6.8% in year 1 to 8.4% in year 2, then dropped back to 6.8% in year 3, and the mortality differences were not statistically significant,” he said. The expected mortality rates were 7.6%, 8.1%, and 5.9%.
Geometric length of stay remained below the comparative group and declined each year, from 4.1% to 3.7%.
“Over the 3 years, our performance measure improved as reported to the National Hospital Quality Measures Program. Our mortality rate remained unchanged and our geometric length of stay decreased,” Dr. Frohna said.
The discrepancy between the findings of the New Jersey Medical School and Union Memorial Hospital studies and the 2004 study may be attributable to the fact that the 2004 retrospective study included only Medicare patients older than 65 years, Dr. Frohna explained.
Dr. Frohna cautioned emergency physicians to “be on the front lines of making sure that performance measures actually link to improved outcomes,” and not look the other way while others dictate how they treat their patients.