Because initially adequate antibiotic therapy is so important in reducing the mortality from VAP, when patients are at risk for MDR organisms, initial therapy should be broad and known to be effective against MDR pathogens, especially P aeruginosa and MRSA, and tailored to the local antibiogram. Current guidelines3 suggest that this will usually require three antibiotics: two drugs of different classes active against Pseudomonas, and a third for MRSA. A recommended empiric regimen for these patients is: an antipseudomonal cephalosporin (cefepime, ceftazidime), or an antipseudomonal carbepenem (imipenem, meropenem), or a β-lactam/β-lactamase inhibitor (piperacillin/tazobactam) plus an antipseudomonal fluoroquinolone (ciprofloxacin, levofloxacin), or an aminoglycoside (amikacin, gentamicin, tobramycin) plus either linezolid or vancomycin.3 The initial choice of agents should also take into account any antibiotics the patient has received in the past 2 weeks, striving not to repeat the same antimicrobial class if possible, as recent exposure to one antibiotic can provoke resistance to the entire class.55–56 In patients with suspected VAP who do not have risk factors for MDR pathogens (Table 3), limited-spectrum antibiotic therapy is appropriate. Recommended antibiotics are as follows: ceftriaxone or a fluoroquinolone, or ampicillin/sulbactam or ertapenem.,3 The selection of antibiotic therapy is based on patient risk factors, recent exposure to specific antibiotic classes, and the local antibiogram. Because microbiologic culture data will not be immediately available, the initial antibiotic selection will be the same regardless of the diagnostic methodology employed (BAL, PSB, TA).