What is the role of intravenous-to-oral switch therapy in the treatment of community-acquired pneumonia (CAP)?

Updated: Jul 30, 2018
  • Author: Shirin A Mazumder, MD, FIDSA; Chief Editor: Pranatharthi Haran Chandrasekar, MBBS, MD  more...
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One of the most common uses of intravenous-to-oral (IV-to-PO) switch therapy is in the treatment of CAP. CAP is most commonly caused by Streptococcus pneumoniae infection. The natural history of CAP is beyond the scope of this article; see Pneumonia, Community-Acquired for more information. In terms of switch therapy, approximately 40-50% of patients admitted for intravenous antibiotics can be switched to oral antibiotics within 2-3 days.

The US Medicare Pneumonia Project database provided evidence that the routine practice of in-hospital observation after the switch from intravenous to oral antibiotics in patients with CAP can be avoided in those who are clinically stable. [12] Explicit physiological criteria must be recorded routinely to serve as a benchmark in order for the switch to be consistently successful.

In 1999, Siegel reported that the treatment of hospitalized patients with uncomplicated CAP is changing to include a brief period of intravenous antibiotics followed by oral therapy. [13] The Classification of Community-Acquired Pneumonia (CoCAP) is a stratification tool in which patients are categorized as having low-risk pneumonia, unstable pneumonia, or complicated pneumonia (see the image below). Caregivers can achieve a structure for organizing treatment of patients with CAP by using (1) validated hospital admission criteria, (2) the CoCAP algorithm, and (3) newly evolving criteria for switching patients from intravenous to oral therapy.

A Japanese multicenter randomized study of early-switch therapy from intravenous sulbactam/ampicillin to oral garenoxacin in CAP was successful. [14]

The Classification of Community-Acquired Pneumonia The Classification of Community-Acquired Pneumonia

Patients with unstable pneumonia can be discharged early if (1) their metabolic problems have reversed and comorbid conditions have stabilized and (2) they have not developed any serious pneumonia-related complications. Prolonged courses of intravenous antibiotic therapy are being replaced with 2- to 3-day courses of intravenous hydration and antibiotics; patients can be switched to oral therapy and can be discharged from the hospital after they tolerate one dose of oral therapy. The vital signs and the WBC count should be monitored, and, provided these parameters are improving (although possibly not normalized), patients can be switched to oral therapy.

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