722. Normal clinical signs and duration of antibiotics in hospitalized patients with pneumonia
Session: Poster Abstract Session: Respiratory Infections: Viral
Thursday, October 4, 2018
Room: S Poster Hall
Background: The most common reason for antibiotic prescribing in hospitalized patients is suspected respiratory tract infection. In many cases, however, antibiotics may be started when the diagnosis is unclear and continued for a fixed course regardless of patients’ clinical trajectories. We sought to characterize the distribution of clinical signs in patients started on antibiotics for possible pneumonia, number of days to normalization of clinical signs, and duration of antibiotics beyond when signs normalized.

Methods: We performed a retrospective analysis on 43,820 consecutive adults admitted to Brigham and Women’s Hospital from May 2017 to Jan 2018. We identified all non-ventilated patients started on antibiotics for pneumonia using clinicians’ stated indications in their medication orders. We analyzed the distribution of clinical signs indicative of pneumonia (maximum temperature, maximum white blood cell count, median respiratory rate, and supplemental oxygen need) on the first day of antibiotics. We then calculated median days to normalization for each sign, total days of antibiotics for pneumonia, and duration of antibiotics beyond when all signs normalized.

Results: We identified 2,754 non-ventilated patients started on antibiotics for pneumonia. On the first day of antibiotics, 38%had oxygen saturations ≥95% without supplemental oxygen, 78% had normal temperatures, 63% had normal white blood cell counts, and 79% had median respiratory rates <22 breaths/minute. All signs were normal in 25% of patients. Amongst those with at least one abnormal clinical sign on the first day of antibiotics, all signs returned to normal within a median of 3 days (IQR 2-7 days). Antibiotics were nonetheless continued for ≥3 more days in 33% of these patients.

Conclusion: Pneumonia is a major driver of antibiotic utilization in hospitalized patients but we found 25% of cases lacked the cardinal clinical signs of pneumonia and antibiotics were continued for ≥3 days after all clinical signs normalized in a third of the 75% of patients who did have signs of pneumonia. These findings suggest substantial opportunities to improve antibiotic prescribing for suspected respiratory tract infections in hospitalized patients.

Aileen Ochoa, MPH1, Wenjing Ji, MS1,2, Cara Smith, MPH1, Chanu Rhee, MD, MPH3,4 and Michael Klompas, MD, MPH4,5, (1)Harvard Pilgrim Health Care Institute, Boston, MA, (2)Xi’an Jiaotong University, Xian, China, (3)Division of Infectious Diseases, Brigham and Women's Hospital, Boston, MA, (4)Department of Population Medicine, Harvard Medical School and Harvard Pilgrim Health Care Institute, Boston, MA, (5)Brigham and Women's Hospital, Boston, MA


A. Ochoa, None

W. Ji, None

C. Smith, None

C. Rhee, None

M. Klompas, None

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