Implementation of a Guideline for Community-Acquired Pneumonia is Associated with a Reduction in Antibiotic Class Switching and Length of Therapy

Background: Community-acquired pneumonia (CAP) is the most common reason for hospital admission for antibiotic treatment.  CAP can be treated with short durations (< 7 days) of relatively narrow-spectrum antibiotics.  We previously demonstrated that unnecessary resource utilization, transition to a new antibiotic class at discharge, and excessive treatment durations were common.  We developed and implemented an institutional guideline for the management of CAP and report on its impact.

Methods: The guideline was a one-page decision support algorithm developed with multi-disciplinary input.  Use of CT scan if an infiltrate was present on chest radiograph, routine sputum culture, and prescription of a new antibiotic class at discharge were discouraged.   A 5-day total duration of therapy was recommended in clinically responding cases.  The guideline was published on an internal website and publicized by peer champions at staff meetings.  We performed a retrospective review of adults admitted with CAP between 5/1/2010-5/31/2011(baseline period) and 7/1/2011-7/31/2012 (intervention period).  The primary outcomes evaluated were use of sputum culture and CT scan, antibiotic class-switching (with exposure to 3 or more drug classes, and the duration of therapy.

Results: 166 and 46 patients were included in the baseline and intervention periods, respectively.  Use of sputum culture decreased from 84 (51%) cases during the baseline period to 7(15%) during the intervention (p=0.02).  Use of chest CT decreased from 39 (50%) to 12 (26%) cases (p=0.14). Changes in antibiotic use included the following: 

 

Outcome	Baseline	Intervention	p-value
Initial therapy with B-lactam+ macrolide	147 (89%)	43 (93%)	0.40
New antibiotic class at discharge	97 (66%)	15 (35%)	0.004
Discharge therapy
Macrolide	29 (17%)	22 (48%)	< 0.0001
Fluoroquinolone	99 (60%)	15 (33%)	0.001
Median length of therapy (Interquartile range (IQR))	10 (8-14)	7 (5-8)	<0.0001

Conclusion: Implementation of a CAP guideline was associated with reductions in resource utilization, use of a new antibiotic class at discharge, and total length of therapy.  Antibiotic stewardship programs that target antibiotic use through institutional guideline implementation can have a substantial impact on prescribing practices.