Clinical Update: Guidelines for managing hospital-aquired Pneumonia

The American Thoracic Society (ATS) and the Infectious Diseases Society of America recently published guidelines for the management of hospital-acquired pneumonia (HAP).¹ These guidelines, which are an update of a 1996 ATS consensus statement,² focus on bacterial HAP in immunocompetent adults. This includes ventilator-associated pneumonia (VAP) and health care-associated pneumonia (HCAP). Selected highlights are presented here.

Definitions

HAP is defined as pneumonia that occurs 48 hours or more after admission and that was not incubating at the time of admission. VAP is defined as pneumonia that arises more than 48 to 72 hours after endotracheal intubation.

HCAP is defined as pneumonia in a patient who was hospitalized in an acute-care hospital for 2 or more days within 90 days of the infection; resided in a nursing home or long-term-care facility; received recent intravenous antibiotic therapy, chemotherapy, or wound care within the past 30 days of the current infection; or attended a hospital or hemodialysis clinic.

Patient evaluation

Culture of a lower respiratory tract specimen should be performed in all patients but should not delay the initiation of therapy in critically ill patients (Figure). Specimens can be obtained bronchoscopically or nonbronchoscopically, and treatment can be based on either semiquantitative or quantitative culture data.

Antibiotic therapy can be discontinued in a patient with negative lower respiratory tract culture results who has had cultures obtained without an antibiotic change within the past 72 hours.

Empiric antibiotic therapy

Patients with pneumonia should receive early, appropriate, broad-spectrum antibiotic therapy at adequate dosages that optimize efficacy. Empiric therapy should include antibiotics that are from a different class than the one the patient has recently received.

Initial empiric antibiotic therapy should be administered intravenously; it can be switched to oral/ enteral therapy in select patients who have a good clinical response and a functioning intestinal tract. For patients with early-onset disease who have no known risk factors for multidrug-resistant pathogens, the options for initial empiric therapy include ceftriaxone, a fluoroquinolone (levofloxacin, moxifloxacin, ciprofloxacin), ampicillin/ sulbactam, or ertapenem.

The risk factors for pneumo- nia caused by multidrug-resistant pathogens include antibiotic therapy within the preceding 90 days, current hospitalization of 5 days or more, a high frequency of antibiotic resistance in the community or in the specific hospital unit, and immunosuppressive disease or therapy. Risk factors for HCAP include hospitalization for 2 days or more within the preceding 90 days, residence in a nursing home or extended-care facility, home infusion therapy (including antibiotics), long-term dialysis within 30 days, home wound care, and a family member who has infection caused by a multidrug-resistant pathogen.

Patients with late-onset disease or risk factors for multidrug-resistant pathogens should receive combination therapy that consists of an antipseudomonal cephalosporin (cefepime, ceftazidime) or an antipseudomonal carbapenem (imipenem, meropenem), or a ß-lactam/ß-lactamase inhibitor (piperacillin-tazobactam) plus an antipseudomonal fluoroquinolone (ciprofloxacin, levofloxacin), or an aminoglycoside (amikacin, gentamicin, tobramycin) plus linezolid or vancomycin (Table 1). Preliminary data suggest that linezolid may have an advantage over vancomycin for the treatment of VAP caused by methicillin-resistant Staphylococcus aureus.

Colistin should be considered in patients with VAP caused by a carbapenem-resistant Acinetobacterspecies. Aerosolized antibiotics may have some benefit as adjunctive therapy in patients with VAP caused by certain multidrug-resistant pathogens.

If the patient's initial antibiotic regimen was appropriate, efforts should be made to shorten the duration of therapy to as little as 7 days, provided that the causative pathogen is not Pseudomonas aeruginosaand that the patient has a good clinical response. Four major principles in the management of HAP, VAP, and HCAP are summarized in Table 2.

References:

REFERENCES

1. American Thoracic Society; Infectious Diseases Society of America. Guidelines for the management of adults with hospital-acquired, ventilator-associated, and healthcare-associated pneumonia.

Am J Respir Crit Care Med.

2005;171:388-416.
2. American Thoracic Society. Hospital-acquired pneumonia in adults: diagnosis, assessment of severity, initial antimicrobial therapy, and preventive strategies [consensus statement].

Am J Respir Crit Care Med.

1996; 153:1711-1725.