Empiric antibiotics pending bronchoalveolar lavage data in patients without pneumonia significantly alters the flora, but not the resistance profile, if a subsequent pneumonia develops.

Ventilator-associated pneumonia (VAP) occurs in up to 25% of mechanically ventilated patients, with an associated mortality up to 50%. Early diagnosis and appropriate empiric antibiotic coverage of VAP are crucial. Given the multitude of noninfectious clinical and radiographic anomalies within trauma patients, microbiology from bronchioalveolar lavage (BAL) is often needed. Empiric antibiotics are administered while awaiting BAL culture data. Little is known about the effects of these empiric antibiotics on patients with negative BAL microbiology if a subsequent VAP occurs during the same hospital course. This is a retrospective chart review of intubated trauma patients undergoing BAL for suspected pneumonia over a 3-y period at a Level 1 trauma center. All patients with suspected VAP undergoing a BAL receive empiric antibiotics. If microbiology data are negative at 72 h, all antibiotics are stopped; however, if the BAL returns with ≥10(5) colony-forming units per milliliter, the diagnosis of VAP is confirmed. We divided patients into three groups. Group 1 consisted of patients in whom the initial BAL was positive for VAP. Group 2 consisted of patients with an initial negative BAL, who subsequently developed VAP at a later point in the hospital course. Group 3 consisted of patients with negative BAL who did not develop a subsequent VAP. We obtained 499 BAL specimens in 185 patients over the 3-y period. A total of 14 patients with 23 BAL specimens initially negative for VAP subsequently developed VAP later during the same hospital stay. These patients did not have an increase in the hospital length of stay, intensive care unit days, ventilator days, or mortality compared with those who had a positive culture on the first suspicion of VAP. There was a significant increase in the percentage of Enterobacter (21% versus 8%) and Morganella (8% versus 0%) as the causative organism in these 14 patients when the VAP occurred. Furthermore, the profile of the top two organisms in each group changed. Enterobacter (21%) and Pseudomonas (17%) were the principal organisms in the initial BAL-negative group, whereas the two predominant strains in the initial positive BAL group were methicillin-sensitive Staphylococcus aureus (21%) and Haemophilus influenza (11%). Interestingly, methicillin-resistant S. aureus remained the third most common organism in both groups. Empiric antibiotics also did not seem to induce the growth of multidrug-resistant organisms, and there was no increased rate of secondary infections such as Clostridium difficile. Ventilator-associated pneumonia remains a significant cause of morbidity and mortality in mechanically ventilated trauma patients. The diagnosis and treatment of VAP continue to be challenging. Once clinically suspected, empiric coverage decreases morbidity and mortality. Our data demonstrate that patients who receive empiric coverage exhibit a significantly different microbiologic profile compared with those who had an initial positive BAL culture. Initial empiric antibiotics in BAL-negative patients were not associated with an increase in multidrug-resistant organisms, hospital, or intensive care unit length of stay, ventilator days, and mortality or secondary infections.

Thakkar RK ，Monaghan SF ，Adams CA Jr ，Stephen A ，Connolly MD ，Gregg S ，Cioffi WG ，Heffernan DS ... -  《-》

Pneumonia in the surgical intensive care unit: is every one preventable?

Pneumonia is a major complication for hospitalized patients and has come under the scrutiny of health care regulating bodies, which propose that hospital-acquired pneumonia should not be reimbursed and potentially be a "never event." We hypothesized that many of our acutely injured patients develop pneumonia at the time of their initial traumatic event despite aggressive measures to prevent pneumonia during hospitalization. This retrospective review included all mechanically ventilated patients admitted to a mixed surgical intensive care units (ICU; trauma, general surgery, and burns) who developed pneumonia from 2006 to 2008. All pneumonia diagnosed by culture were obtained from bronchoalveolar lavage (BAL) specimens with ≥ 10(4) colony forming united (CFU)/mL considered a positive result. Criteria for ventilator-associated pneumonia (VAP) applied only to those patients ventilated mechanically for >48 hours at the time of a positive BAL culture. Aspiration organisms included Streptococcus species, methicillin-sensitive Staphylococcus aureus, Haemophilus influenzae, and oral flora. This was an institutional review board-approved study. There were 208 mechanically ventilated who patients underwent BAL, half of which were performed in the first 48 hours after admission for fever, infiltrate on chest radiograph, or increasing white blood cell count (early BAL group). Of these patients, 58% had positive BAL cultures (pneumonia) but did not have VAP. Only 10% of patients studied with early BAL had no growth on culture. Although the predominant organisms in the early BAL group were aspiration-type organisms, 17% had resistant pathogens, and 16% had other Gram-negative rods (GNR). This percentage was compared with the VAP group in whom 33% of patients had resistant organisms (P = .04) and 8% other GNR (P = NS). Twenty-five patients with ≤ 10(4) CFU/mL on early BAL underwent repeat BAL, and 16 (64%) were later diagnosed with VAP. Many intubated patients in the surgical ICU had evidence of early pneumonia or bacterial growth within 48 hours after arrival, suggesting early infection or colonization occurred before ICU admission. In addition, 33% with early bacterial growth on early BAL had resistant organisms or GNR on BAL culture, which suggests a patient-derived rather than environmentally acquired source.

Wahl WL ，Zalewski C ，Hemmila MR 《-》

Hospital-acquired pneumonia and ventilator-associated pneumonia in adults at Siriraj Hospital: etiology, clinical outcomes, and impact of antimicrobial resistance.

Werarak P ，Kiratisin P ，Thamlikitkul V 《-》

Differences in management and mortality with a bronchoalveolar lavage-based diagnostic protocol for ventilator-associated pneumonia.

Michetti CP ，Aldaghlas T 《-》

Does bronchoalveolar lavage enhance our ability to treat ventilator-associated pneumonia in a trauma-burn intensive care unit?

Wahl WL ，Franklin GA ，Brandt MM ，Sturm L ，Ahrns KS ，Hemmila MR ，Arbabi S ... -  《journal of trauma-injury infection and critical care》