The IDSA/ATS recently released guidelines (pdf here) for ventilator associated (VAP) and hospital acquired pneumonia (HAP.  These guidelines are full of interesting updates on the care of these patients, but interestingly, they weigh in on a old ID debate: double coverage for Pseudomonas aeruginosa.

Classically the debate has been framed in two spheres: empiric therapy and definitive therapy. The variable resistance of Pseudomonas makes predicting an active agent more difficult, so in some settings “double coverage” (that is two agents with activity) is favored.

The guidelines delineate who should receive considerate for empiric double coverage:

In VAP: Those with acute dialysis needs, those in septic shock, those admitted 5+ days prior, those with ARDS preceding VAP and those with IV antibiotics within last 90 days.

However: if >10% of all Gram Negative pathogens in the ICU are resistant to the a chosen mono-therapy agent, double coverage should be used

In HAP: (more simply): Those with IV antibiotics within last 90 days

Given the guideline discourage aminoglycoside use (they do not penetrate lung tissue to the alveoli very well), any patient meeting the above conditions should likely be on a Beta-lactam + fluoroquinolone.

Regarding definite therapy for Pseudomonas related VAP/HAP:

Monotherapy with an active agent based on testing is recommended in most cases, with the exception of ongoing septic shock and “high risk for death” (25% or more estimate).  The authors due note that definite dual coverage is a weak recommendation with low quality evidence.

Overall the guideline opinion on dual coverage or double coverage is relatively liberal in the empiric phase, with a focus on targeted therapy in most cases for definitive therapy.

One wonders what the rates of adherence to these guidelines will be across medical centers and units, and also whether antibiotic utilization of various classes will increase or decrease as a results.

Full guidelines published in CID.

Pubmed citation:  Kalil, AC et al Clinical Infectious Diseases, 2016 ; 63 : 1 -51

[JAV]