Etiology Of Ventilator-associated Pneumonia Research Articles

The efficiency of routine endotracheal aspirate cultures compared to bronchoalveolar lavage cultures in ventilator-associated pneumonia diagnosis.

Ventilator-associated pneumonia (VAP) is the most common nosocomial infection in İntensive Care Units (ICUs) and its mortality rate varies from 24% to 50%. The most important factor in decreasing the mortality is administering adequate antibiotics as early as possible. In this study, we investigate the efficiency of routine endotracheal aspirate (EA) cultures to identify the etiology of VAP earlier. Fifty-nine patients who were accepted to our ICU with acute cerebrovascular disease with mechanical ventilation (MV) requirement were chosen for this study over a 12-month period. The patients intubated in our ICU were included in the study to exclude prior colonization. Upon ICU admission, the patient's; age, sex, comorbidities, diagnosis, acute physiology and chronic health evaluation II score, and sequential organ failure assessment (SOFA) score were recorded. When bronchoalveolar lavage (BAL) was performed, the SOFA score, temperature, leukocyte count, C-reactive protein levels, PaO2/FiO2ratio, PCO2, clinical pulmonary infection score value, length of MV, and presence of antimicrobiological treatments were recorded. Routine microbiological analysis was performed by EA (pre-VAP EA) twice weekly in all patients until the endotracheal tube was removed. When VAP was suspected, fiberoptic bronchoscopy examination with BAL was performed. A diagnosis of VAP was established when the BAL quantitative culture grew at least one microorganism at a concentration ≥104 cfu/mL. VAP was diagnosed in 41 (69%) of the 59 patients based on BAL culture results. Among 41 positive BAL cultures, pre-VAP EA identified the same microorganism with the same antibiotics resistance pattern in 23 (56%) patients. Regarding only late-onset VAP, pre-VAP EA identified the same microorganisms found by BAL culture in 17 (63%) of the 27 cases. Among 18 BAL culture negative patients, 7 (39%) patients had negative prior pre-VAP EA culture results. Acinetobacter baumannii was the most frequently isolated microorganism from BAL cultures (n = 21, 51%). The diagnostic value of pre-VAP EA results in predicting A. baumannii VAP documented with the following values (sensitivity: 62%; specificity: 95%, positive predictive value: 87%, negative predictive value: 82%). VAP patients should be treated with international guidelines, but if pre-VAP EA cultures identify multidrug resistant pathogens, the initial antibiotic therapy should cover these microorganisms. Thus, quantitative EA cultures are a useful noninvasive diagnostic tool in critically ill patients suspected of having pneumonia especially in the case of VAP.

Trauma-associated pneumonia: time to redefine ventilator-associated pneumonia in trauma patients

BackgroundThe high prevalence of ventilator-associated pneumonia (VAP) in trauma patients has been reported in the literature, but the reasons for this observation remain unclear. We hypothesize that trauma factors play critical roles in VAP etiology. MethodsIn this retrospective study, 1,044 ventilated trauma patients were identified from December 2010 to December 2013. Patient-level trauma factors were used to predict pneumonia as study endpoint. ResultsNinety-five of the 1,044 ventilated trauma patients developed pneumonia. Rib fractures, pulmonary contusion, and failed prehospital intubation were significant predictors of pneumonia in a multivariate model. ConclusionsIt is time to redefine VAP in trauma patients based on the effect of rib fractures, pulmonary contusions, and failed prehospital intubations. The Centers for Disease Control and Prevention definition of VAP needs to be modified to reflect the effect of trauma factors in the etiology of trauma-associated pneumonia.

Ventilator-associated pneumonia monitoring according to the INICC project at one centre.

Pneumonia is a common complication of hospitalisation in severely ill patients who need mechanical ventilation. The aim of this study was to assess the usefulness of the International Nosocomial Infection Control Consortium programme for the surveillance of ventilator-associated pneumonia (VAP). A prospective study (1 Jan 2012-30 June 2014) was conducted in the 20-bed ICU. The device utilisation ratios for lung ventilation and the frequency (density and incidence) and aetiology of VAP were estimated in ICU patients. From a total of 1097 patients, VAP infections were diagnosed in 93. Thirty percent of patients with VAP died. The incidence index was 8.47 per 100 admissions to the ICU. VAP infections accounted for 46% of the overall count of device-associated healthcare-associated infections. Mechanical ventilation was used in 71 ± 8 patients during the 11 862 patient days and 8425 ventilation days. The rate of VAP per 1000 ventilator days was 11.15/9.34 /10.23 in years 2012/2013/2014 (half a year), respectively. The main VAP pathogens were Acinetobacter baumannii (45%) and Pseudomonas aeruginosa (17%). During the reported time span, the incidence of VAP was lower than in the INICC report (2007-2012), but it was tenfold higher than in the NHSN/CDC report (dated 2012). Because of the unchanged VAP level during the 2.5-year observation period, the root cause needs to be determined and action should be taken to resolve this issue.

Drug-resistant ventilator associated pneumonia in a tertiary care hospital in Saudi Arabia.

BACKGROUND:There is a wide geographic and temporal variability of bacterial resistance among microbial causes of ventilator-associated pneumonia (VAP). The contribution of multi-drug resistant (MDR) pathogens to the VAP etiology in Saudi Arabia was never studied. We sought to examine the extent of multiple-drug resistance among common microbial causes of VAP.MATERIALS AND METHODS:We conducted a retrospective susceptibility study in the adult intensive care unit (ICU) of King Abdulaziz Medical City, Riyadh, Saudi Arabia. Susceptibility results of isolates from patients diagnosed with VAP between October 2004 and June 2009 were examined. The US National Healthcare Safety Network definition of MDR was adopted.RESULTS:A total of 248 isolates including 9 different pathogens were included. Acinetobacter spp. was highly (60-89%) resistant to all tested antimicrobials, including carbapenems (three- and four-class MDR prevalence were 86% and 69%, respectively). Pseudomonas aeruginosa was moderately (13-31%) resistant to all tested antimicrobials, including antipseudomonal penicillins (three- and four-class MDR prevalence were 13% and 10%, respectively). With an exception of ampicillin (fully resistant), Klebsiella spp. had low (0-13%) resistance to other tested antimicrobials with no detected MDR. Staphylococcus aureus was fully susceptible to vancomycin with 42% resistance to oxacillin. There were significant increasing trends of MDR Acinetobacter spp. however not P. aeruginosa during the study. Resistant pathogens were associated with worse profile of ICU patients but not patients’ outcomes.CONCLUSION:Acinetobacter in the current study was an increasingly resistant VAP-associated pathogen more than seen in many parts of the world. The current finding may impact local choice of initial empiric antibiotics.

P069: Drug-resistant acinetobacter ventilator-associated pneumonia: a time for desperate measures!

There is a wide geographic and temporal variability of bacterial resistance among microbial causes of ventilator-associated pneumonia (VAP). The contribution of multi-drug resistant (MDR) pathogens to the VAP etiology in Saudi Arabia was never studied.

Estudo bacteriológico do lavado broncoalveolar na gestão de antibióticos na pneumonia associada à ventilação mecânica de pacientes em unidades de terapia intensiva cirúrgica

To determine the correlation of Gram staining with the culture of bronchoalveolar lavage in patients with clinical features of ventilator-associated pneumonia from two adult trauma and surgical intensive care units. We conducted a retrospective study of 252 samples of bronchoalveolar lavage from patients with clinical ventilator-associated pneumonia in trauma or surgical postoperative care. Gram staining samples were classified as Gram-positive cocci and Gram-negative bacilli, all other results being excluded. Cultures from bronchoalveolar lavage were compared with Gram staining results. The correlation between Gram staining and culture from the bronchoalveolar lavage showed a kappa index of 0.27. The sensitivity of Gram staining was 53.9% and the specificity, 80.6%. Considering the identification of Gram-positive cocci against other results (negative and Gram-negative bacilli), the negative predictive value was 94.8%. The evaluation of Gram-negative bacilli against other results (negative and Gram-positive cocci) rendered a sensitivity of 27.1% and a specificity of 95.4%. It appears that the negative predictive value for Gram-positive cocci is acceptable, but the sensitivity of Gram staining in the etiology of ventilator-associated pneumonia was not able to identify the microorganism before culture.

Procalcitonin in early onset ventilator-associated pneumonia

Ventilator-associated pneumonia (VAP) is a significant problem in intensive care and there exists great demand for a suitable biomarker. Procalcitonin (PCT) has been proposed as a candidate marker. To assess the clinical usefulness of monitoring PCT concentrations in non-surgical patients with early onset VAP. Thirty-four patients were enrolled with early onset VAP defined as VAP diagnosed between 48 h and 6 days of the onset of mechanical ventilation. Serum PCT was measured on days 1, 2, 3, 5, 6 and 7. The mortality rate was 21%. Non-survivors had significantly elevated PCT levels on days 3 and 7. For non-survival, the areas under the receiver operator curve (AUC) for PCT were 0.762 [95% confidence interval (CI): 0.6-0.923] on day 3 and 0.754 (95% CI: 0.586-0.922) on day 7. Among septic patients, PCT was significantly higher on days 1, 2, 3, 5, and 7, with the highest AUC on day 1 (0.783; 95% CI: 0.626-0.94): a cut-off of 1 ng/mL on day 1 had a positive predictive value of 0.813 for the development of septic shock. No association was found between PCT concentration and the adequacy of antibiotic therapy or the aetiology of VAP. In logistic regression analysis, PCT was not significantly correlated with poor outcome. Although PCT levels were higher in non-survivors and those who developed septic shock, PCT is not a strong predictor of these outcomes.

O6-5.4 Ventilator-associated pneumonia in patients with severe burn injury: the predictive value of routine surveillance cultures to predict multidrug resistance

IntroductionBurn patients with inhalation injury requiring mechanical ventilation (MV) are at particular risk for ventilator-associated pneumonia (VAP), which is associated with increased morbidity and mortality. Routine endotracheal surveillance cultures (SC)...

Should the ATS/IDSA Guidelines for Hospital-acquired and Ventilator-associated Pneumonia be Reevaluated?

We have revised the effects of implementing the current and former guidelines for the management and treatment of ventilator-associated pneumonia (VAP) on the outcome of intensive care unit patients, with particular focus on issues related to VAP etiology, pathogen prediction, appropriate empiric antibiotic therapy, and mortality. Several studies showed that in patients with clinical suspicion of VAP, appropriate antibiotic therapy administered in a timely manner could improve survival. The guidelines for the management and treatment of VAP have been developed to help physicians achieve these goals. Implementation of these guidelines into clinical practice is difficult to achieve and requires extensive education for healthcare personnel and translation of recommendations into local protocols. Studies have shown that guideline implementation is associated with better outcome. However, extensive research needs to be undertaken to validate the efficacy of guidelines in predicting the etiology of pneumonia, in particular, to promptly identify multidrug-resistant pathogens. A recent report has validated the latest guidelines and has called attention for further research to improve microbial prediction.

Bacterial aetiology in ventilator-associated pneumonia at a Swedish university hospital

Ventilator-associated pneumonia (VAP) is a common complication of respiratory support and is associated with increased mortality, morbidity and costs, and a prolonged stay in the intensive care unit. Scandinavian data on the aetiology in VAP are lacking. We hereby present a retrospective study on the aetiology of VAP diagnosed by protective specimen brush culture at Malmö University Hospital in relation to early- and late-onset VAP, antibiotic treatment and the incidence of drug-resistant bacteria. Patients registered with a diagnosis of VAP between January 2004 and September 2007 were included in the study. Sixty-five of 109 patients diagnosed with VAP met the inclusion criteria, and 103 bacterial isolates were cultured from these patients. The most common findings among the 65 VAP episodes were Enterobacteriaceae (28), Pseudomonas aeruginosa (13), Haemophilus influenzae (12) and Staphylococcus aureus (8). Patients with no antibiotic treatment at the onset of VAP had significantly more H. influenzae (p = 0.035) and Gram-positive pathogenic bacteria (p = 0.019). There was no difference in incidence of P. aeruginosa between early- and late-onset VAP. Resistant bacteria were found in 18% of the patients.

Do guidelines change outcomes in ventilator-associated pneumonia?

The purpose of the study is to summarize effects of implementation of current and past guidelines for management and treatment of ventilator-associated pneumonia (VAP) on outcome of intensive care patients, with particular focus on etiology of VAP, pathogens prediction, appropriate empiric antibiotic therapy and mortality. Several studies have shown that in patients with clinical suspicion of VAP, appropriate antibiotic therapy administered in a timely manner can improve survival. Guidelines for management and treatment of VAP have been developed to help physicians to achieve those goals. Implementation of guidelines into clinical practice is difficult to achieve and requires extensive education for healthcare personnel and translation of recommendations into local protocols. Studies have shown that guidelines implementation is associated with better outcome. However, extensive research needs to be undertaken in order to validate efficacy of guidelines in predicting etiology of pneumonia, in particular, to promptly identify multidrug-resistant pathogens. Only one recent report has validated the latest guidelines and called attention for further research to improve microbial prediction. Guidelines implementation can improve outcomes. To achieve this goal, guidelines should be adapted to local microbiology, accurately predict VAP pathogens and help physicians to administer the most appropriate empirical antimicrobial therapy.

Ventilator-associated pneumonia in a tertiary care hospital in India: role of multi-drug resistant pathogens

Ventilator-Associated Pneumonia (VAP) is the most frequent intensive-care-unit (ICU)-acquired infection. The aetiology of VAP varies with different patient populations and types of ICUs. A prospective study was performed over a period of 15 months in a tertiary care hospital to determine the various aetiological agents causing VAP and the prevalence of multidrug resistant (MDR) pathogens. Combination disk method, Modified Hodge test, EDTA disk synergy (EDS) test and AmpC disk test were performed for the detection of extended spectrum beta-lactamases (ESBL), carbapenemases, metallo-beta-lactamases (MBL) and AmpC beta-lactamases respectively. Enterobacteriaceae, Haemophilus influenzae, Staphylococcus aureus, Streptococcus pneumoniae, Candida spp. were more common in early-onset VAP, while non-fermenters (Pseudomonas spp. and Acinetobacter spp.) were significantly associated with late-onset VAP (P value 0.0267, Chi-square value 4.91). Thirty-seven (78.7%) of the 47 VAP pathogens were multidrug resistant. ESBL was produced by 50% and 67% of Escherichia coli and Klebsiella pneumoniae respectively. MBL was produced by 20% of P. aeruginosa. AmpC beta-lactamases were produced by 33.3% and 60.7% of the Enterobacteriaceae and non-fermenters respectively. Of the S. aureus isolates, 43% were methicillin resistant. Prior antibiotic therapy and hospitalization of five days or more were independent risk factors for VAP by MDR pathogens. VAP is increasingly associated with MDR pathogens. Production of ESBL, AmpC beta-lactamases and metallo beta-lactamases were responsible for the multi-drug resistance of these pathogens. Increasing prevalence of MDR pathogens in patients with late-onset VAP indicate that appropriate broad-spectrum antibiotics should be used to treat them.

Redefining Success for VAP: 360-Degree Approach

BACKGROUND: Ventilator-associated pneumonia (VAP) in hospital intensive care units (ICUs) is associated with high morbidity and mortality. Effective treatment of VAP can be challenging due to a high prevalence of Pseudomonas aeruginosa and multidrug-resistant (MDR) pathogens as causative organisms. OBJECTIVE: To present the etiology of VAP in the United States (including national resistance trends of common nosocomial pathogens) and review dosing strategies aimed to optimize pharmacokinetic-pharmacodynamic parameters of antimicrobial agents. SUMMARY: The majority of nosocomial pneumonia cases are caused by gram-negative pathogens, most commonly P. aeruginosa, Enterobacter spp., A. baumannii, and K. pneumoniae. S. aureus is the most common gram-positive pathogen, with 55% of VAP isolates exhibiting methicillin resistance. Combination therapy is recommended when MDR pathogens and P. aeruginosa are suspected, although short-course therapy and deescalation should be considered when appropriate to reduce the risk of resistance. Optimized dosing strategies are important in increasing the probability of achieving successful outcomes. For example, when administering intravenous β-lactam therapy, prolonged infusion can be effective in increasing the T > MIC. CONCLUSION: Clinicians need to be familiar with local antibiograms as well as regional resistance trends in order to choose appropriate therapy for VAP. Optimized dosing strategies can be effective in increasing the probability of attaining pharmacokinetic-pharmacodynamic targets predictive of successful clinical outcomes. J Manag Care Pharm. 2009;15(5)(Suppl):S5-S9 Copyright © 2009, Academy of Managed Care Pharmacy. All rights reserved. DAVID S. BURGESS, PharmD, FCCP, is Clinical Professor of Pharmacy and Medicine, University of Texas at Austin, Austin, Texas, and the University of Texas Health Science Center at San Antonio, San Antonio, Texas. CORRESPONDENCE: David S. Burgess, PharmD, FCCP, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, MSC 6220, San Antonio, TX 78229-3900. Tel.: 210.567.8329; Fax: 210.567.8328; E-mail: burgessd@uthscsa.edu Author Introduction Ventilator-associated pneumonia (VAP) is among the most common nosocomial infections originating in the intensive care unit (ICU), affecting 9% to 27% of all intubated patients.1,2 The attributable mortality can be as high as 33% to 50%.1,2 The risk of VAP is correlated to the length of stay (LOS) in the hospital or ICU as well as to the duration of mechanical ventilation.2 Pseudomonas aeruginosa and multidrug-resistant (MDR) organisms account for over 20% of VAP infections, with higher rates observed in those with prolonged hospitalization.3 Infection by these problematic pathogens is associated with increased mortality, duration of mechanical ventilation, and hospital LOS.3 Therefore, when managing patients at high risk for VAP, it is important to recognize the local epidemiology and resistance trends in order to select the most appropriate initial antimicrobial therapy. Etiology of Hospital-Acquired Pneumonia Surveillance data from the National Healthcare Safety Network (NHSN, formerly the National Nosocomial Infections Surveillance System) have shown that gram-negative pathogens are the predominant cause of nosocomial pneumonia, accounting for approximately 70% of infections.4 Among the infections caused by gram-negative pathogens, P. aeruginosa is the leading cause (accounting for approximately 20%) followed by Enterobacter spp., Klebsiella pneumoniae, and Acinetobacter baumannii.4 The proportion of infections due to Acinetobacter has nearly doubled over the past 2 decades (from 4% in 1986 to 7% in 2003). However, there has been a gradual trend of increasing infections due to grampositive pathogens, mainly Staphylococcus aureus. The etiology of VAP can vary based on (a) local epidemiological trends as well as (b) the timing of onset of infection. According to the 2006–2007 NHSN data, the most common pathogen associated with VAP is S. aureus (24.4%) followed by P. aeruginosa (16.3%), Enterobacter spp. (8.4%), A. baumannii (8.4%), and K. pneumoniae (7.5%) (Table 1).5 The time of onset is also an important predictor of causative pathogens. Early-onset VAP, defined as VAP occurring within the first 5 days of hospitalization, is caused by enteric gram-negative bacteria (including Escherichia coli, K. pneumoniae, and Enterobacter spp.), Haemophilus influenzae, Streptococcus pneumoniae, and methicillin-susceptible S. aureus (MSSA).2,6 Late-onset VAP, defined as VAP occurring after 5 days of hospitalization, is more likely to be caused by MDR pathogens,2,6 including those associated with early-onset VAP as well as P. aeruginosa and A. baumannii. The variety and complexity of pathogens associated with VAP make choosing an appropriate initial therapy challenging. Appropriate Antimicrobial Therapy for VAP The American Thoracic Society (ATS) and the Infectious Diseases

Curbing resistance development: maximizing the utility of available agents.

Ventilator-associated pneumonia (VAP) in hospital intensive care units (ICUs) is associated with high morbidity and mortality. Effective treatment of VAP can be challenging due to a high prevalence of Pseudomonas aeruginosa and multidrug-resistant (MDR) pathogens as causative organisms. To present the etiology of VAP in the United States (including national resistance trends of common nosocomial pathogens) and review dosing strategies aimed to optimize pharmacokinetic-pharmacodynamic parameters of antimicrobial agents. The majority of nosocomial pneumonia cases are caused by gram-negative pathogens, most commonly P. aeruginosa, Enterobacter spp., A. baumannii, and K. pneumoniae. S. aureus is the most common gram-positive pathogen, with 55% of VAP isolates exhibiting methicillin resistance. Combination therapy is recommended when MDR pathogens and P. aeruginosa are suspected, although short-course therapy and deescalation should be considered when appropriate to reduce the risk of resistance. Optimized dosing strategies are important in increasing the probability of achieving successful outcomes. For example, when administering intravenous -lactam therapy, prolonged infusion can be effective in increasing the T > MIC. Clinicians need to be familiar with local antibiograms as well as regional resistance trends in order to choose appropriate therapy for VAP. Optimized dosing strategies can be effective in increasing the probability of attaining pharmacokinetic-pharmacodynamic targets predictive of successful clinical outcomes.

Ventilator-associated pneumonia after procedures in cardiac surgery

Surveillance of hospital-acquired infections in intensive care wards is a very important but time-consuming process requiring involvement of all medical personnel [1]. This means published data on infections after cardiac surgery are rather limited [2]. The aim of this study was to analyze the epidemiology and etiology of ventilator-associated pneumonia (VAP) following coronary surgery in ICU patients.

Determinants and impact of multidrug antibiotic resistance in pathogens causing ventilator-associated-pneumonia.

IntroductionThe idea that multidrug resistance (MDR) to antibiotics in pathogens causing ventilator-associated pneumonia (VAP) is an independent risk factor for adverse outcome is still debated. We aimed to identify the determinants of MDR versus non-MDR microbial aetiology in VAP and assessed whether MDR versus non-MDR VAP was independently associated with increased 30-day mortality.MethodsWe performed a retrospective analysis of a prospectively registered cohort of adult patients with microbiologically confirmed VAP, diagnosed at a university hospital intensive care unit during a three-year period. Determinants of MDR as compared with non-MDR microbial aetiology and impact of MDR versus non-MDR aetiology on mortality were investigated using multivariate logistic and competing risk regression analysis.ResultsMDR pathogens were involved in 52 of 192 episodes of VAP (27%): methicillin-resistant Staphylococcus aureus in 12 (6%), extended-spectrum β-lactamase producing Enterobacteriaceae in 28 (15%), MDR Pseudomonas aeruginosa and other non-fermenting pathogens in 12 (6%). Multivariable logistic regression identified the Charlson index of comorbidity (odds ratio (OR) = 1.38, 95% confidence interval (CI) = 1.08 to 1.75, p = 0.01) and previous exposure to more than two different antibiotic classes (OR = 5.11, 95% CI = 1.38 to 18.89, p = 0.01) as predictors of MDR aetiology. Thirty-day mortality after VAP diagnosis caused by MDR versus non-MDR was 37% and 20% (p = 0.02), respectively. A multivariate competing risk regression analysis showed that renal replacement therapy before VAP (standardised hazard ratio (SHR) = 2.69, 95% CI = 1.47 to 4.94, p = 0.01), the Charlson index of comorbidity (SHR = 1.21, 95% CI = 1.03 to 1.41, p = 0.03) and septic shock on admission to the intensive care unit (SHR = 1.86, 95% CI = 1.03 to 3.35, p = 0.03), but not MDR aetiology of VAP, were independent predictors of mortality.ConclusionsThe risk of MDR pathogens causing VAP was mainly determined by comorbidity and prior exposure to more than two antibiotics. The increased mortality of VAP caused by MDR as compared with non-MDR pathogens was explained by more severe comorbidity and organ failure before VAP.

Comparison of the surveillance with quantitative and nonquantitative ETA cultures in predicting ventilator-associated pneumonia etiology in patients receiving antibiotic therapy

It is not yet clear whether surveillance of lower respiratory tract secretions should be performed routinely and which method should be used for this. The aim of the present study is to investigate the value of quantitative (QC-ETA) and nonquantitative (NQC-ETA) surveillance cultures in predicting the causative pathogen of ventilator-associated pneumonia (VAP) in patients receiving antibiotic therapy.

Etiología de la neumonía asociada a ventilación mecánica en un hospital clínico: Asociación con co-morbilidad, uso previo de antimicrobianos y mortalidad

Ventilator-associated pneumonia (VAP) is a complication with an increased risk of morbidity and mortality. Inadequate antibiotic treatment is a risk factor of mortality which can be improved. For this reason it is important to know the local etiology of VAP. During a one year-period we investigated the etiology of VAP in a teaching hospital. Forty eight VAP were included, of which 19 were women. The median age was 59.5 (range 17-91 years), twelve VAP were early onset. Methicillin resistant Staphylococcus aureus (MRSA) was the main microorganism isolated, regardless of timing of diagnosis of VAP, followed by polimicrobial etiology, Acinetobacter sp and P. aeruginosa. Etiology was not associated with comorbidity; however previous antibiotic use was related with MRSA and polymicrobial etiology. Mortality was 35% and was mainly associated with P. aeruginosa isolation. MRSA was the main cause of VAP regardless of the timing of its occurrence.

Are routine endotracheal aspirates predictive of the etiology of ventilator-associated pneumonia?

Most investigators discuss the predictive value of respiratory surveillance cultures in mechanically ventilated patients and doubt on the appropriate selection of the antibiotic therapy based on these findings, when pneumonia develops. The aim of our study was to evaluate whether microorganisms cultured from semiquantitative tracheal aspirates (SQTA) in the 48 hours prior to the clinical suspicion of ventilator-associated pneumonia (VAP) were predictive of the etiology, compared with the bronchoalveolar lavage (BAL) results performed on the same day that the clinical diagnosis was considered

Impact of BAL Data on the Therapy and Outcome of Ventilator-Associated Pneumonia

To define the impact of BAL data on the selection of antibiotics and the outcomes of patients with ventilator-associated pneumonia (VAP). Prospective observation and bronchoscopy with BAL, performed within 24 h of establishing a clinical diagnosis of a new episode of hospital-acquired VAP or progression of a prior episode of nosocomial pneumonia (NP). A 15-bed medical and surgical ICU. One hundred thirty-two patients hospitalized for more than 72 h, who were mechanically ventilated and had a new or progressive lung infiltrate plus at least two of the following three clinical criteria for VAP: abnormal temperature (> 38 degrees C or < 35 degrees C), abnormal leukocyte count (> 10,000/mm3 or < 3,000/mm3), purulent bronchial secretions. Bronchoscopy with BAL within 24 h of establishing a clinical diagnosis of VAP or progression of an infiltrate due to prior VAP or NP. All patients received antibiotics, 107 prior to bronchoscopy and 25 immediately after bronchoscopy. Sixty-five of the 132 patients were BAL positive (BAL[+]), satisfying a microbiologic definition of VAP (> 10(4) cfu/mL), while 67 were BAL negative (BAL[-]). The BAL(+) patients had no differences in mortality, prior antibiotic use, and demographic features when compared with the BAL(-) patients. More of the BAL(+) patients (38/65) satisfied all three clinical criteria of VAP than did BAL(-) patients (24/67) (p < 0.05). A total of 50 BAL(+) patients received antibiotic therapy prior to bronchoscopy, and when this prior therapy was adequate (n = 16), as defined by the results of BAL, then mortality was 38%, while if prior therapy was inadequate (n = 34), mortality was 91% (p < 0.001), and if no therapy was given (n = 15), mortality was 60%. When therapy changes were made after bronchoscopy, more patients (n = 42) received adequate therapy, but mortality in this group was comparable to mortality among those who continued to receive inadequate therapy (n = 23). A total of 46 of the 65 BAL(+) patients died, with 23 of these deaths occurring during the 48 h after the bronchoscopy, before BAL results were known. When BAL data became available, 37 of the 42 surviving patients received adequate therapy, but their mortality was comparable to the patients who continued to receive inadequate therapy. Patients with a strong clinical suspicion of VAP have a high mortality rate, regardless of whether BAL cultures confirm the clinical diagnosis of VAP. When adequate antibiotic therapy is initiated very early (ie, before performing bronchoscopy), mortality rate is reduced if this empiric therapy is adequate, compared to when this therapy is inadequate or no therapy is given. If adequate therapy is delayed until bronchoscopy is performed or until BAL results are known, mortality is higher than if it had been given at the time of first establishing a clinical diagnosis of VAP. When patients were changed from inadequate antibiotic therapy to adequate therapy, based on the results of BAL, mortality was comparable to those who continued to receive inadequate therapy. Thus, even if bronchoscopy can accurately define the microbial etiology of VAP, this information becomes available too late to influence survival.