Risk Factors For Ventilator-associated Pneumonia Research Articles

Viral colonization in intubated patients: initial pathogen pattern and follow‐up

Colonization of the lower respiratory tract is an independent risk factor for ventilator-associated pneumonia. Little is known about the frequency of viral colonization on intubation and during mechanical ventilation. Overall, 65 eligible intubated patients with no initial signs of pulmonary infection were studied over a period of up to 7 days. Tracheobronchial aspirates were taken: (i) within 48 h after intubation; and (ii) when clinical signs of nosocomial tracheobronchitis were present, before extubation, or after 7 days. Presence of respiratory viruses was investigated using quantitative polymerase chain reaction. Patients were 67 +/- 11 years old and had been in hospital for 5.1 +/- 8.4 days when intubated (major cause for intubation: cardio-pulmonary resuscitation 25/65, 38%). The average Acute Physiology and Chronic Evaluation II score was 27.3 +/- 4.9. Microbiology detected Candida spp. (17/65; 26%) and Staphylococcus aureus (methicillin sensitive: 11/65; 17%; methicillin resistant: 3/65; 5%) and only few respiratory viruses (4/65, 6%). Thirty-eight percent of the samples (25/65) were sterile. At the given endpoints, 27/65 (42%) patients were available for follow-up and only one aspirate became positive for respiratory syncytial virus (RSV). After endotracheal intubation, fungi, but not viruses were most frequently isolated. Only one patient acquired RSV, therefore colonization with respiratory viruses does not seem to play a major role early after intubation.

Keeping Patients Safe During Intrahospital Transport

Keeping Patients Safe During Intrahospital Transport

Ventilator-associated pneumonia in long-term ventilator-assisted individuals

Information on the characteristics of pneumonia in long-term ventilator-assisted individuals is scarce. We evaluate the incidence, risk factors and outcome of ventilator-associated pneumonia (VAP) in a large series of chronically ventilated patients. All patients assisted in a chronic ventilator-dependent unit were prospectively followed up for the development of VAP. Patients with a new and persistent lung infiltrate and a purulent tracheal aspirate were suspected to have VAP. Pneumonia was considered microbiologically confirmed in the presence of (1) a positive blood culture and/or (2) ≥10⁵ CFU ml⁻¹ in quantitative bacterial culture of tracheal aspirates or ≥10³ CFU ml⁻¹ in quantitative mini-bronchoalveolar lavage cultures. In total, 100 consecutive long-term ventilated individuals with spinal cord injury (mean age 49 years) were prospectively followed up. The length of mechanical ventilation before admission in the unit was 54±37 days, and the follow-up after admission was 119±127 days. There were 32 episodes of VAP in 27 patients (1.74 episodes per 1000 days of mechanical ventilation). By logistic regression analysis, hypoalbuminaemia (P=0.03), administration of antacids (P=0.002) and length of mechanical ventilation (P=0.05) were independent risk factors for VAP. The most frequently isolated organisms were Pseudomonas aeruginosa (62%), methicillin-resistant Staphylococcus aureus (25%) and Acinetobacter baumannii (15%); 9 (28%) episodes were polymicrobial. Antimicrobial treatment, including monotherapy in 66%, was successful in most patients. Only three patients (11%) died in relation to VAP. Patients on long-term ventilation are at significant risk for the development of VAP, but the mortality is low.

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.

Pneumonia associada à ventilação mecânica: epidemiologia e impacto na evolução clínica de pacientes em uma unidade de terapia intensiva

Although ventilator-associated pneumonia (VAP) is a major cause of nosocomial infection, its role in the prognosis of patients remains undefined. The objective of this study was to evaluate the impact of VAP on the clinical evolution of patients. This was a prospective cohort study involving 233 patients on mechanical ventilation (VAP group, n = 64; control group, n = 169). Primary outcomes were time on mechanical ventilation (TMV), time in ICU (TICU), overall length of hospital stay (LHS) and in-ICU mortality. Secondary outcomes were in-hospital mortality, microbiological profile, prior use of antibiotics and risk factors for VAP acquisition. Control and VAP group outcomes were, respectively, as follows: median TMV (days), 9 (interquartile range [IQR]: 5-15) and 23 (IQR: 15-37; p < 0.0001); median TICU (days), 12 (IQR: 8-21) and 27 (IQR: 17-42; p < 0.0001); median LHS (days), 33 (IQR: 18-64) and 46 (IQR: 25-90; p = 0.05); and in-ICU mortality, 38% (95% CI: 31-45) and 55% (95% CI: 42-67; p = 0.02). VAP was a predictor of in-ICU mortality (OR = 3.40; 95% CI: 1.54-7.48). TMV (OR = 2.27; 95% CI: 1.05-4.87) and prior use of antibiotics (OR = 1.07; 95% CI: 1.04-1.10) were risk factors for VAP. VAP did not affect in-hospital mortality. Acinetobacter spp. was the most common isolate (28%). Inappropriate empirical antibiotic therapy was administered in 48% of cases. In this study, there was a high incidence of infection with resistant bacteria and inappropriate initial antibiotic therapy. Long TMV and prior use of antibiotics are risk factors for VAP.

Non-adherence to guidelines: an avoidable cause of failure of empirical antimicrobial therapy in the presence of difficult-to-treat bacteria

To identify the risk factors of ventilator-associated pneumonia (VAP) due to difficult-to-treat (DTT) bacteria (i.e., Pseudomonas aeruginosa, Acinetobacter baumannii and oxacillin-resistant Staphylococcus aureus), and to assess the rate and the causes of inappropriateness of empirical antimicrobial therapy. In an intensive care unit of a university hospital, patients with VAP were empirically treated with antibiotics without activity against DTT bacteria if the patients had no prior hospitalization or prior administration of antibiotics, according to local guidelines. Overall, the empirical antimicrobial therapy was appropriate in 190 (87%) out of 218 patients with VAP. Fifty (23%) patients developed problems due to DTT bacteria. The risk factors for VAP due to DTT bacteria were shock state, prior antimicrobial therapy, prior stay in long-term care facilities and late-onset VAP. Empirical antimicrobial therapy was inappropriate in 20 (40%) patients with VAP due to DTT bacteria and 8 (5%) patients with VAP due to non-DTT (P = 0.001). Guidelines violations (nine patients), bacteria not included in antibiotic spectrum (eight patients) and bacterial resistance (three patients) were the causes of inappropriateness in case of DTT bacteria. Despite the abundant information for the treatment of VAP and the establishment of guidelines, too many patients with DTT bacteria received inappropriate antimicrobial therapy. Since 45% of the cases are related to non-adherence to the local protocol, there is room for improvement by implementing educational programs. Also, since DTT bacteria are found in 23% of late-onset VAP, empirical antibiotic treatment should be directed against these pathogens.

Risk Factors for Relapse of Ventilator-Associated Pneumonia in Trauma Patients

Our goal was to define risk factors for ventilator-associated pneumonia (VAP) relapse and examine the implications, if any, for initial therapy in trauma patients. Trauma patients cared for in the surgical intensive care unit during a 48-month period with confirmed VAP recurrence were evaluated. Recurrent VAP was defined as a positive quantitative culture (> or = 10(4) colony-forming units/mL in a bronchoalveolar lavage or protected catheter lavage specimen) > or = 4 days after initiation of antibiotics for the primary episode. Recurrence with at least one of the initial causative pathogens was defined as a relapse. Initial causal pathogen, Acute Physiology and Chronic Health Evaluation II score, injury severity score, Glasgow Coma Score (GCS), age, white blood cell count (WBC), and duration of hospital stay before diagnosis were analyzed in univariate and multivariate regression models. A total of 55 patients met the criteria of recurrent VAP. Of these 55 recurrences, 19 (35%) were relapses. Acute Physiology and Chronic Health Evaluation II score, injury severity score, and GCS were not associated with VAP relapse by univariate analyses. Patients who relapsed had primary VAP involving nonfermenting gram-negative bacilli (NFGNB) (Acinetobacter, Pseudomonas, and Stenotrophomonas species) more frequently than other organisms (68% vs. 32%, p = 0.001). Primary VAP with NFGNB was found to be a significant predictor of VAP relapse by univariate and multivariate logistic regression analysis (OR = 5.1, p = 0.003; OR = 4.63, p = 0.005, respectively). There is a high rate of VAP relapse associated with primary infection by NFGNB, suggesting initial treatment failure. Trauma patients with primary VAP involving these organisms may benefit from increased surveillance for relapse.

Ventilator-associated pneumonia in pediatric trauma patients

Ventilator-associated pneumonia (VAP) is a significant cause of secondary morbidity and mortality in adult trauma patients. No study has characterized VAP in pediatric trauma patients. We determined the rates of and potential risk factors for VAP in pediatric trauma patients. A countywide trauma registry identified all pediatric trauma patients with potential VAP treated at a Regional Trauma Center. After a structured chart review, descriptive statistics were used to characterize the population. One hundred fifty-eight trauma patients younger than 16 years requiring intubation and mechanical ventilation were identified in 3388 pediatric trauma admissions from the period 1995-2006. Drownings and poisonings were excluded. The registry identified 14 potential VAPs, of which, on detailed review, 7 were true cases. The VAP rate for pediatric trauma patients was 0.2% overall or 4.4% of those mechanically ventilated. In addition, ventilator days were available in the registry from 2003 forward and the rate in ventilator days was found to be 13.83/1000. Although higher than the overall pediatric intensive care unit VAP rate (5.93/1000 ventilator days), the pediatric trauma VAP rate was substantially lower than the VAP rate in adult trauma patients (58.25/1000 ventilator days). On chart review, six of the seven patients were male and older than 10 years (mean age, 11.9 years). All seven patients with VAP were blunt trauma victims with head injury (mean initial Glasgow Coma Score, 5.6) with Injury Severity Scores over 25 (mean, 32.1). Pulmonary contusion was present in four of the seven. Although the in-hospital mortality rate of ventilated pediatric trauma patients was 17.1%, there was no mortality in those with VAP. The rate of VAP in pediatric trauma patients is substantially lower than in similar adults. Age older than 10 years, blunt trauma, head injury, and Injury Severity Score >25 may be risk factors. VAP is not associated with increased mortality in pediatric trauma patients.

Incidence and risk factors for ventilator-associated pneumonia after major heart surgery

Major heart surgery (MHS) patients are a particularly high-risk population for nosocomial infections. Our objective was to identify risk factors for ventilator-associated pneumonia (VAP) in patients undergoing MHS. Prospective study including 1,844 patients operated from 2003 to 2006. Overall 106 patients (140 episodes) developed one or more episodes of VAP (5.7%, 22.2 episodes per 1,000 days of mechanical ventilation). VAP incidence was 45.9% in those patients requiring more than 48 h of MV. Enterobacteriaceae (32.8), Pseudomonas aeruginosa (28.6%) and Staphylococcus aureus (27.1%, of which 65.8% were methicillin resistant) were the principal microorganisms causing VAP. The independent risk factors for VAP were: age >70, perioperative transfusions, days of mechanical ventilation, reintubation, previous cardiac surgery, emergent surgery and intraoperative inotropic support. Median length of stay in the ICU for patients who developed VAP or not was, respectively, 25.5 versus 3 days (P < 0.001), and mortality was, respectively, 45.7 versus 2.8% in both populations (P < 0.001). We developed a predictive preoperative score with a sensitivity of 93% and a specificity of 40%. VAP is common in patients undergoing MHS that require more than 48 h of MV. In that "high-risk" population, innovative preventive measures should be developed and applied.

Prevention of ventilator-associated pneumonia after cardiac surgery: prepare and defend!

Prevention of ventilator-associated pneumonia after cardiac surgery: prepare and defend!

Ventilator-Associated Tracheobronchitis

Nosocomial lower respiratory tract infections are a common cause of morbidity and mortality in ICU patients receiving mechanical ventilation. Many studies have investigated the management and prevention of ventilator-associated pneumonia (VAP), but few have focused on the role of ventilator-associated tracheobronchitis (VAT). The pathogenesis of lower respiratory tract infections often begins with tracheal colonization that may progress to VAT, and in selected patients to VAP. Since there is no well-established definition of VAT, discrimination between VAT and VAP can be challenging. VAT is a localized disease with clinical signs (fever, leukocytosis, and purulent sputum), microbiologic information (Gram stain with bacteria and leukocytes, with either a positive semiquantitative or a quantitative sputum culture), and the absence of a new infiltrate on chest radiograph. Monitoring endotracheal aspirates has been used to identify and quantify pathogens colonizing the lower airway, to diagnose VAT or VAP, and to initiate early, targeted antibiotic therapy. Recent data suggest that VAT appears to be an important risk factor for VAP and that targeted antibiotic therapy for VAT may be a new paradigm for VAP prevention and better patient outcomes. Nosocomial lower respiratory tract infections are a common cause of morbidity and mortality in ICU patients receiving mechanical ventilation. Many studies have investigated the management and prevention of ventilator-associated pneumonia (VAP), but few have focused on the role of ventilator-associated tracheobronchitis (VAT). The pathogenesis of lower respiratory tract infections often begins with tracheal colonization that may progress to VAT, and in selected patients to VAP. Since there is no well-established definition of VAT, discrimination between VAT and VAP can be challenging. VAT is a localized disease with clinical signs (fever, leukocytosis, and purulent sputum), microbiologic information (Gram stain with bacteria and leukocytes, with either a positive semiquantitative or a quantitative sputum culture), and the absence of a new infiltrate on chest radiograph. Monitoring endotracheal aspirates has been used to identify and quantify pathogens colonizing the lower airway, to diagnose VAT or VAP, and to initiate early, targeted antibiotic therapy. Recent data suggest that VAT appears to be an important risk factor for VAP and that targeted antibiotic therapy for VAT may be a new paradigm for VAP prevention and better patient outcomes. VAT vs VAP: Are We Heading Toward Clarity or Confusion?CHESTVol. 135Issue 2PreviewThe Centers for Medicare and Medicaid Services have recently stopped reimbursing hospitals for several preventable complications including nosocomial infections such as vascular catheter-related bloodstream infections and catheter-associated urinary tract infections. The proposal that reimbursement for ventilator-associated pneumonia (VAP) would be one of the next “preventable complications” added to the list for nonreimbursement was met with disapproval by many intensivists and hospital administrators as there is often some degree of uncertainty in making the diagnosis and because VAP is likely not entirely preventable. Full-Text PDF

Gastroesophageal reflux in mechanically ventilated pediatric patients and its relation to ventilator-associated pneumonia

IntroductionThe objective was to determine the frequency of gastroesophageal reflux (GER) in mechanically ventilated pediatric patients and its role as a risk factor for ventilator-associated pneumonia (VAP), which may be enhanced among those patients.MethodsThe study is a prospective cohort study of mechanically ventilated pediatric patients in the pediatric intensive care unit (PICU) of Ain Shams University Children's Hospital. It was conducted in 24 mechanically ventilated patients (16 of them developed VAP and 8 did not, with mean age of 16.6 +/- 20.5 and 18.6 +/- 22.4 months respectively). Esophageal 24-hour pH-metry beside clinical and laboratory evaluation of their underlying problem and severity of their condition were carried out.ResultsAll VAP patients had GER (50% alkaline reflux, 12.5% acidic reflux and 37.5% combined reflux) compared to 75% of non-VAP ones (100% alkaline reflux). The mean total reflux time was significantly longer among VAP (50 minutes) versus non-VAP (3 minutes) patients. There was significant increase in acidic reflux parameters among non-survivors versus survivors (P < 0.001). For VAP mortality, total acidic reflux at a cut-off value of 28.6 minutes is found to be a mortality predictor with a sensitivity of 100% and a specificity of 100%.ConclusionsGER is a constant incident in mechanically ventilated pediatric patients, with alkaline reflux being more common than acidic reflux. Both acidic and alkaline refluxes were found to be associated with the development of VAP and total reflux time was found to be a reliable predictor of VAP. Moreover, acidic reflux was found to be more related to mortality than alkaline reflux.

Ventilator-associated pneumonia in patients undergoing major heart surgery: an incidence study in Europe

IntroductionPatients undergoing major heart surgery (MHS) represent a special subpopulation at risk for nosocomial infections. Postoperative infection is the main non-cardiac complication after MHS and has been clearly related to increased morbidity, use of hospital resources and mortality. Our aim was to determine the incidence, aetiology, risk factors and outcome of ventilator-associated pneumonia (VAP) in patients who have undergone MHS in Europe.MethodsOur study was a prospective study of patients undergoing MHS in Europe who developed suspicion of VAP. During a one-month period, participating units submitted a protocol of all patients admitted to their units who had undergone MHS.ResultsOverall, 25 hospitals in eight different European countries participated in the study. The number of patients intervened for MHS was 986. Fifteen patients were excluded because of protocol violations. One or more nosocomial infections were detected in 43 (4.4%) patients. VAP was the most frequent nosocomial infection (2.1%; 13.9 episodes per 1000 days of mechanical ventilation). The microorganisms responsible for VAP in this study were: Enterobacteriaceae (45%), Pseudomonas aeruginosa (20%), methicillin-resistant Staphylococcus aureus (10%) and a range of other microorganisms. We identified the following significant independent risk factors for VAP: ascending aorta surgery (odds ratio (OR) = 6.22; 95% confidence interval (CI) = 1.69 to 22.89), number of blood units transfused (OR = 1.08 per unit transfused; 95% CI = 1.04 to 1.13) and need for re-intervention (OR = 6.65; 95% CI = 2.10 to 21.01). The median length of stay in the intensive care unit was significantly longer (P < 0.001) in patients with VAP than in patients without VAP (23 days versus 2 days). Death was significantly more frequent (P < 0.001) in patients with VAP (35% versus 2.3%).ConclusionsPatients undergoing aortic surgery and those with complicated post-intervention courses, requiring multiple transfusions or re-intervention, constitute a high-risk group probably requiring more active preventive measures.

Positive-end expiratory pressure reduces incidence of ventilator-associated pneumonia in nonhypoxemic patients*

To analyze the effect on clinical outcomes of prophylactic positive end expiratory pressure in nonhypoxemic ventilated patients. Multicenter randomized controlled clinical trial. One trauma and two general intensive care units in two university hospitals. One hundred thirty-one mechanically ventilated patients with normal chest radiograph and PaO2/FiO2 above 250. Patients were randomly allocated to receive mechanical ventilation with 5-8 cm H2O of positive end-expiratory pressure (PEEP) (PEEP group, n = 66) or no-PEEP (control group, n = 65). Primary end-point variable was hospital mortality. Secondary outcomes included microbiologically confirmed ventilator-associated pneumonia, acute respiratory distress syndrome, barotrauma, atelectasis, and hypoxemia (PaO2/FiO2 <175). Both groups were similar at randomization in demographic characteristics, intensive care unit admission diagnoses, severity of illness, and risk factors for ventilator-associated pneumonia. Hospital mortality rate was similar (p = 0.58) between PEEP (29.7%) and control (25.4%) groups. Ventilator-associated pneumonia was detected in 16 (25.4%) patients in the control group and 6 (9.4%) in the PEEP group (relative risk, 0.37; 95% confidence interval = 0.15-0.84; p = 0.017). The number of patients who developed hypoxemia was significantly higher in the control group (34 of 63 patients, 54%) than in the PEEP group (12 of 64, 19%) (p < 0.001), and the hypoxemia developed after a shorter period (median [interquartile range]) in the control group than in the PEEP group (38 [20-70] hrs vs. 77 [32-164] hrs, p < 0.001). Groups did not significantly differ in incidence of acute respiratory distress syndrome (14% in controls vs. 5% in the PEEP group, p = 0.08), barotrauma (8% vs. 2%, respectively, p = 0.12), or atelectasis (27% vs. 19%, respectively, p = 0.26). These findings indicate that application of prophylactic PEEP in nonhypoxemic ventilated patients reduces the number of hypoxemia episodes and the incidence of ventilator-associated pneumonia.

Blood Product Transfusion and Ventilator-Associated Pneumonia in Trauma Patients

Ventilator-associated pneumonia (VAP) is the most common nosocomial infection in trauma patients, with a high mortality rate. Blood transfusion has been identified as an independent risk factor for VAP in critically ill patients. Prior studies in trauma are limited by retrospective design, lack of multivariable analyses, and scant data on the timing of transfusion. We examined critically the relation between blood product transfusion and VAP in trauma patients. Prospective observational cohort study of 766 trauma patients admitted to the intensive care unit (ICU), who received mechanical ventilation (MV) for >or= 48 h, and who did not have pneumonia on admission. Late-onset VAP was defined as that occurring >or= 72 h after MV. Only transfusions of red blood cell (RBC) concentrate, fresh-frozen plasma (FFP), or platelets before the onset of VAP were considered. Logistic regression analyses controlled for all variables related significantly to VAP by univariate analysis (sex, Injury Severity Score, and ventilator days and ICU length of stay prior to VAP). A significantly greater proportion of male patients developed VAP. Patients with VAP had a longer duration of MV: The mean number ventilator days prior to VAP was 11.1 +/- 8.0. Transfusion of blood products was an independent risk factor for VAP, and the risk increased with more units transfused. All blood products were associated with a higher risk of VAP (RBC: odds ratio [OR] 4.41; 95% confidence interval [CI] 1.00, 19.54; p = 0.05; FFP: OR 3.34; 95% CI 1.18, 9.43; p = 0.023; platelets: OR 4.19; 95% CI 1.37, 12.83; p = 0.012). Blood product transfusion is an independent risk factor for VAP in trauma, and the odds ratio is significantly higher (3.34-4.41) than in published studies of other types of ICU patients (1.89). To reduce the incidence of VAP, all efforts to reduce the transfusion of blood products to trauma patients should be implemented.

Risk factors and pathogenic analysis in the newborn infants with ventilator-associated pneumonia

Objective To investigate the risk factors and microbial causes related to the pathogenesis of ventilator-associated pneumonia(VAP).Methods Totaly 138 intubated newborn infants for longer than 48 hours in Ningbo Women and Children's Hospital were studied,who were divided into VAP group (56 cases)and non VAP group(82 cases).Microbial causes of VAP were analyzed.Results Malnutrition,repeated tracheal intubation,repeated endotracheal suctioning,indwelling tube,posture,hyaline membrane disease,gestational age,birth weight,duration of intubation,duration of hospitalization were independent risk factors for ventilator-associated pneumonia(P<0.05).Klebsiella pneumoniae,pseudomonas aeruginosa,acinetobacter species and enterobacter cloacae were the main pathogenic bacteria of VAP.Conclusion Shortening of mechanical ventilation duration,avoiding repeated tracheal intubation and indwelling tube usage,semi-fowler positioning can lower the incidence of VAP.Pathogenic bacteria control is essential for VAP. Key words: Newborn; Ventilator-associated pneumonia; Risk factors

Closed Tracheal Suction Systems Versus Open Tracheal Suction Systems for Mechanically Ventilated Adult Patients

Background Ventilator-associated pneumonia is a common complication in ventilated patients. Endotracheal suctioning is a procedure that may constitute a risk factor for ventilator-associated pneumonia. It can be performed with an open system or with a closed system. In view of suggested advantages being reported for the closed system, a systematic review comparing both techniques was warranted. Objectives To compare the closed tracheal suction system and the open tracheal suction system in adults receiving mechanical ventilation for more than 24 hours. Search methods We searched CENTRAL (The Cochrane Library 2006, Issue 1) MEDLINE, CINAHL, EMBASE and LILACS from their inception to July 2006. We handsearched the bibliographies of relevant identified studies, and contacted authors and manufacturers. Selection criteria The review included randomized controlled trials comparing closed and open tracheal suction systems in adult patients who were ventilated for more than 24 hours. Data collection and analysis We included the relevant trials fitting the selection criteria. We assessed methodological quality using method of randomization, concealment of allocation, blinding of outcome assessment and completeness of follow up. Effect measures used for pooled analyses were relative risk (RR) for dichotomous data and weighted mean differences (WMD) for continuous data. We assessed heterogeneity prior to meta-analysis. Main results Of the 51 potentially eligible references, the review included 16 trials (1684 patients), many with methodological weaknesses. The two tracheal suction systems showed no differences in risk of ventilator-associated pneumonia (11 trials; RR 0.88; 95% CI 0.70 to 1.12), mortality (five trials; RR 1.02; 95% CI 0.84 to 1.23) or length of stay in intensive care units (two trials; WMD 0.44; 95% CI -0.92 to 1.80). The closed tracheal suction system produced higher bacterial colonization rates (five trials; RR 1.49; 95% CI 1.09 to 2.03). Authors' conclusions Results from 16 trials showed that suctioning with either closed or open tracheal suction systems did not have an effect on the risk of ventilator-associated pneumonia or mortality. More studies of high methodological quality are required, particularly to clarify the benefits and hazards of the closed tracheal suction system for different modes of ventilation and in different types of patients.

Ventilator-Associated Pneumonia as a Quality Indicator for Patient Safety?

The economic and clinical burden of ventilator-associated pneumonia (VAP) is uncontested. In many hospitals, VAP surveillance is conducted to identify outbreaks and to monitor infection rates. Here, we discuss the concept of benchmarking in health care as modeled on industry, and we contribute personal arguments against considering the VAP rate as a potential candidate for benchmarking or for monitoring the quality of patient care. Accurate benchmarking of VAP rates currently seems to be unfeasible, because the patient case mix is often too diverse and complicated to be adjusted for, and diagnostic criteria and surveillance protocols vary. Thus, the risk of drawing inaccurate comparisons is high. In contrast, some risk factors for VAP are modifiable and can be monitored and used as quality indicators. Process-oriented surveillance permits bypass of case-mix and diagnostic constraints. A well-defined interhospital surveillance system is necessary to prove that interventions on procedures do really lead to a reduction of VAP rates.

The incidence and microbial spectrum of ventilator-associated pneumonia after tracheotomy in a selective decontamination of the digestive tract-setting

Tracheotomy is considered to be an independent risk factor for ventilator-associated pneumonia (VAP). Antimicrobial prophylaxis, in particular with coverage of Pseudomonas aeruginosa, is presently advocated. Selective decontamination of the digestive tract (SDD) aims to prevent VAP in critically ill patients, including those after tracheotomy. We determined the incidence and microbial spectrum of VAP after tracheotomy in a SDD-setting. Retrospective analysis of 231 tracheotomized patients during a 2-year period. Thirteen patients (5.6%) developed VAP. The median [IQR] day of onset was 8.0 [3.0-10.5] days after tracheotomy. The most predominant causative pathogen was Methicillin-sensitive Staphylococcus aureus (MSSA). Timing of tracheotomy was not different between patients developing VAP and those who did not. The type of tracheotomy (percutaneous or surgical, 84.6% versus 15.4%) had no significant influence on the incidence of VAP. The incidence of VAP after tracheotomy in a SDD-setting is low, with MSSA as the predominant causative pathogen. Accordingly, if antimicrobial prophylaxis is considered, it may be advisable to cover MSSA in an SDD-setting.

Ventilator-Associated Pneumonia

Ventilator-Associated Pneumonia