Early Diagnosis Of Ventilator-associated Pneumonia Research Articles

Exhaled air profile in the early diagnosis of ventilator-associated pneumonia.

To predict exhaled air in patients undergoing mechanical ventilation during bedside diagnosis of ventilator-associated pneumonia. Air samples were collected through the expiratory branch of the mechanical ventilation circuit during the hospitalization of patients at the intensive care unit of Hospital São José in Criciúma (SC), Brazil. In this study, 83 participants were divided into two groups, namely, the group with and the group without ventilator-associated pneumonia. The analysis of three air patterns revealed a predictive value for the diagnosis of ventilator-associated pneumonia. The analyses of samples from the first 12 hours of invasive mechanical ventilation were able to predict ventilator-associated pneumonia (p = 0.018). However, none of the other air samples collected during hospitalization were useful in identifying the severity or predicting early or late ventilator-associated pneumonia. The use of a gas analyzer may be helpful for the early identification of patients admitted to intensive care who will develop ventilator-associated pneumonia.

Predicting ventilator-associated pneumonia in elderly patients requiring mechanical ventilation through the detection in tracheal aspirates

ABSTRACT Objective In this study, we evaluated the clinical utility of tracheal aspirates α-amylase (AM), pepsin, and lipid-laden macrophage index (LLMI) in the early diagnosis of ventilator-associated pneumonia (VAP) in elderly patients on mechanical ventilation. Methods Within 96 hours of tracheal intubation, tracheal aspirate specimens were collected from elderly patients on mechanical ventilation; AM, pepsin, and LLMI were detected, and we analyzed the potential of each index individually and in combination in diagnosing VAP. Results Patients with VAP had significantly higher levels of AM, pepsin, and LLMI compared to those without VAP (P < 0.001), and there was a positive correlation between the number of pre-intubation risk factors of aspiration and the detection value of each index in patients with VAP (P < 0.001). The area under a receiver operating characteristic (ROC) curve (AUC) of AM, pepsin, and LLMI in diagnosis of VAP were 0.821 (95% CI:0.713–0.904), 0.802 (95% CI:0.693–0.892), and 0.621 (95% CI:0.583–0.824), the sensitivities were 0.8815, 0.7632, and 0.6973, the specificities were 0.8495, 0.8602, and 0.6291, and the cutoff values were 4,321.5 U/L, 126.61 ng/ml, and 173.5, respectively. The AUC for the combination of indexes in diagnosing VAP was 0.905 (95% CI:0.812–0.934), and the sensitivity and specificity were 0.9211 and 0.9332, respectively. In the tracheal aspirate specimens, the detection rate of AM ≥ cutoff was the highest, while it was the lowest for LLMI (P < 0.001). The detection rates of AM ≥ cutoff and pepsin ≥ cutoff were higher within 48 hours after intubation than within 48–96 hours after intubation (P < 0.001). In contrast, the detection rate of LLMI ≥ cutoff was higher within 48–96 hours after intubation than within 48 hours after intubation (P < 0.001). The risk factors for VAP identified using logistic multivariate analysis included pre-intubation aspiration risk factors (≥3), MDR bacteria growth in tracheal aspirates, and tracheal aspirate AM ≥ 4,321.5 U/L, pepsin ≥ 126.61 ng/ml, and LLMI ≥ 173.5. Conclusion The detection of AM, pepsin, and LLMI in tracheal aspirates has promising clinical utility as an early warning biomarker of VAP in elderly patients undergoing mechanical ventilation.

Evaluation of the Kinetics of Pancreatic Stone Protein as a Predictor of Ventilator-Associated Pneumonia.

Ventilator-associated pneumonia (VAP) is a severe condition. Early and adequate antibiotic treatment is the most important strategy for improving prognosis. Pancreatic Stone Protein (PSP) has been described as a biomarker that increases values 3-4 days before the clinical diagnosis of nosocomial sepsis in different clinical settings. We hypothesized that serial measures of PSP and its kinetics allow for an early diagnosis of VAP. The BioVAP study was a prospective observational study designed to evaluate the role of biomarker dynamics in the diagnosis of VAP. To determine the association between repeatedly measured PSP and the risk of VAP, we used joint models for longitudinal and time-to-event data. Of 209 patients, 43 (20.6%) patients developed VAP, with a median time of 4 days. Multivariate joint models with PSP, CRP, and PCT did not show an association between biomarkers and VAP for the daily absolute value, with a hazard ratio (HR) for PSP of 1.01 (95% credible interval: 0.97 to 1.05), for CRP of 1.00 (0.83 to 1.22), and for PCT of 0.95 (0.82 to 1.08). The daily change of biomarkers provided similar results, with an HR for PSP of 1.15 (0.94 to 1.41), for CRP of 0.76 (0.35 to 1.58), and for PCT of 0.77 (0.40 to 1.45). Neither absolute PSP values nor PSP kinetics alone nor in combination with other biomarkers were useful in improving the prediction diagnosis accuracy in patients with VAP. Registered retrospectively on August 3rd, 2012. NCT02078999.

Clinical Decision Support System to Detect the Occurrence of Ventilator-Associated Pneumonia in Pediatric Intensive Care.

Ventilator-associated pneumonia (VAP) is a severe care-related disease. The Centers for Disease Control defined the diagnosis criteria; however, the pediatric criteria are mainly subjective and retrospective. Clinical decision support systems have recently been developed in healthcare to help the physician to be more accurate for the early detection of severe pathology. We aimed at developing a predictive model to provide early diagnosis of VAP at the bedside in a pediatric intensive care unit (PICU). We performed a retrospective single-center study at a tertiary-care pediatric teaching hospital. All patients treated by invasive mechanical ventilation between September 2013 and October 2019 were included. Data were collected in the PICU electronic medical record and high-resolution research database. Development of the clinical decision support was then performed using open-access R software (Version 3.6.1®). In total, 2077 children were mechanically ventilated. We identified 827 episodes with almost 48 h of mechanical invasive ventilation and 77 patients who suffered from at least one VAP event. We split our database at the patient level in a training set of 461 patients free of VAP and 45 patients with VAP and in a testing set of 199 patients free of VAP and 20 patients with VAP. The Imbalanced Random Forest model was considered as the best fit with an area under the ROC curve from fitting the Imbalanced Random Forest model on the testing set being 0.82 (95% CI: (0.71, 0.93)). An optimal threshold of 0.41 gave a sensitivity of 79.7% and a specificity of 72.7%, with a positive predictive value (PPV) of 9% and a negative predictive value of 99%, and with an accuracy of 79.5% (95% CI: (0.77, 0.82)). Using machine learning, we developed a clinical predictive algorithm based on clinical data stored prospectively in a database. The next step will be to implement the algorithm in PICUs to provide early, automatic detection of ventilator-associated pneumonia.

Evaluation of Five Host Inflammatory Biomarkers in Early Diagnosis of Ventilator-Associated Pneumonia in Critically Ill Children: A Prospective Single Center Cohort Study.

Background: Early diagnosis of ventilator-associated pneumonia (VAP) remains a challenge due to subjective clinical criteria and the low discriminative power of diagnostic tests. We assessed whether rapid molecular diagnostics in combination with Clinically Pulmonary Index Score (CPIS) scoring, microbiological surveillance and biomarker measurements of PTX-3, SP-D, s-TREM, PTX-3, IL-1β and IL-8 in the blood or lung could improve the accuracy of VAP diagnosis and follow-up in critically ill children. Methods: A prospective pragmatic study in a Pediatric Intensive Care Unit (PICU) was conducted on ventilated critically ill children divided into two groups: high and low suspicion of VAP according to modified Clinically Pulmonary Index Score (mCPIS). Blood and bronchial samples were collected on days 1, 3, 6 and 12 after event onset. Rapid diagnostics were used for pathogen identification and ELISA for PTX-3, SP-D, s-TREM, IL-1β and IL-8 measurements. Results: Among 20 enrolled patients, 12 had a high suspicion (mCPIS > 6), and 8 had a low suspicion of VAP (mCPIS < 6); 65% were male; and 35% had chronic disease. IL-1β levels at day 1 correlated significantly with the number of mechanical ventilation days (rs = 0.67, p < 0.001) and the PICU stay (r = 0.66; p < 0.002). No significant differences were found in the levels of the other biomarkers between the two groups. Mortality was recorded in two patients with high VAP suspicion. Conclusions: PTX-3, SP-D, s-TREM, IL-1β and IL-8 biomarkers could not discriminate patients with a high or low suspicion of VAP diagnosis.

Diagnostic Accuracy of Lung Ultrasound versus Chest Radiograph for Early Diagnosis of Ventilator-associated Pneumonia: An Observational Study

Introduction: Ventilator-associated Pneumonia (VAP) is one of the leading causes of morbidity and mortality in intensive Intensive Care Unit (ICU) and is diagnosed by clinical symptoms, Chest X-ray (CXR), Computerised Tomography (CT) and microbiology test in routine practice. Aim: To compare the diagnostic accuracy of Lung Ultrasound (LUS) with gold standard CXR, with or without modified Clinical Pulmonary Infection Score (CPIS) score, for the diagnosis of VAP in ICU. Materials and Methods: This prospective observational study was carried out on 40 mechanically ventilated patients in Indira Gandhi Medical College and Hospital, Shimla, Himachal Pradesh, India over the duration of one year from November 2018 - October 2019. The study was continued till VAP was diagnosed by all three modalities (CXR, LUS and microbiology) or to the maximum of 10 days postintubation whichever was less. Data was analysed with appropriate statistical tools “MedCalc”. Results: The mean age of patients was 45.78±15.99 years and there were 28 male and 12 females. The diagnosis of VAP was earliest with LUS (3.1±0.81 days) and (4.22±1.23 days) with CXR when studied alone (p&lt;0.0001). However, when LUS was incorporated in CPIS score instead of CXR the diagnostic accuracy were statistically similar (p&gt;0.05). During the early days (3 &amp;4 day) the diagnostic accuracy (AUC), sensitivity and specificity of LUS was better and was (0.70-0.74, 57-90%) than (0.5; 16.7-83%) with CXR. Fifth day onwards AUC was better with CXR (0.79-0.81) as compared to (0.54-0.70) with LUS. Total leucocyte count (TLC), fever, P/F ratio and sputum quantity were observed individually between the VAP and non VAP group patients and were found to be similar (p&gt;0.05). Conclusion: According to the present observational study, LUS can accurately diagnose VAP when other objective tools like CPIS, CXR and microbiology are inconclusive.

The Role of Lung Ultrasound Monitoring in Early Detection of Ventilator-Associated Pneumonia in COVID-19 Patients: A Retrospective Observational Study.

Specific lung ultrasound signs combined with clinical parameters allow for early diagnosis of ventilator-associated pneumonia in the general ICU population. This retrospective cohort study aimed to determine the accuracy of lung ultrasound monitoring for ventilator-associated pneumonia diagnosis in COVID-19 patients. Clinical (i.e., clinical pulmonary infection score) and ultrasound (i.e., presence of consolidation and a dynamic linear–arborescent air bronchogram, lung ultrasound score, ventilator-associated lung ultrasound score) data were collected on the day of the microbiological sample (pneumonia-day) and 48 h before (baseline) on 55 bronchoalveolar lavages of 33 mechanically-ventilated COVID-19 patients who were monitored daily with lung ultrasounds. A total of 26 samples in 23 patients were positive for ventilator-associated pneumonia (pneumonia cases). The onset of a dynamic linear–arborescent air bronchogram was 100% specific for ventilator-associated pneumonia. The ventilator-associated lung ultrasound score was higher in pneumonia-cases (2.5 (IQR 1.0 to 4.0) vs. 1.0 (IQR 1.0 to 1.0); p < 0.001); the lung ultrasound score increased from baseline in pneumonia-cases only (3.5 (IQR 2.0 to 6.0) vs. −1.0 (IQR −2.0 to 1.0); p = 0.0001). The area under the curve for clinical parameters, ventilator-associated pneumonia lung ultrasound score, and lung ultrasound score variations were 0.472, 0.716, and 0.800, respectively. A newly appeared dynamic linear–arborescent air bronchogram is highly specific for ventilator-associated pneumonia in COVID-19 patients. A high ventilator-associated pneumonia lung ultrasound score (or an increase in the lung ultrasound score) orients to ventilator-associated pneumonia.

Serum procalcitonin as an early inflammatory marker in pediatric ventilator-associated pneumonia

Background: Delayed diagnosis of ventilator-associated pneumonia (VAP) in pediatric patients is associated with accentuated risk of morbidities and mortality. Early diagnosis of VAP is challenging. Serum procalcitonin has been proposed as a promising inflammatory marker for the early diagnosis of VAP, but there is a lack of sufficient evidence for the use of serum procalcitonin for early diagnosis of VAP in children. The present study was conducted to determine the role of serum procalcitonin as an early inflammatory marker for an early and provisional diagnosis of VAP among clinically suspected VAP patients in pediatric intensive care unit settings. Subjects and Methods: Seventy-nine pediatric patients (age: 1 month–18 years) with suspected VAP (Simplified Clinical Pulmonary Infection Score &gt;6) were prospectively evaluated with quantitative bronchoalveolar lavage cultures and simultaneously tested for serum procalcitonin levels. Two groups were identified based on culture results and comparatively evaluated for procalcitonin levels, its diagnostic efficacy, antibiotic usage patterns, and mechanical ventilation duration. Results: The VAP group had 39 patients, and the non-VAP group had 40 patients. Thirty-two (82%) patients in the VAP group had a procalcitonin value ≥10 ng/ml as against 10 (25%) from the non-VAP group. Two (5.1%) patients in the VAP group had procalcitonin levels ≤1 ng/ml as against 21 (52.5%) patients in the non-VAP group. The receiver operating characteristic area under curve for procalcitonin with a cutoff &gt;10 ng/ml was 0.785 (95% confidence interval = 0.678–0.870) with a sensitivity of 82.05% and specificity of 75%. Conclusions: Serum procalcitonin is a reliable biomarker to augment the provisional diagnosis of VAP in clinically suspected cases. Such diagnosis may help in an early institution of definitive therapy for VAP.

Usefulness of Sepsis-3 in diagnosing and predicting mortality of ventilator-associated lower respiratory tract infections.

Early distinguishing ventilator-associated tracheobronchitis (VAT) and ventilator-associated pneumonia (VAP) remains difficult in the daily practice. However, this question appears clinically relevant, as treatments of VAT and VAP currently differ. In this study, we assessed the accuracy of sepsis criteria according to the Sepsis-3 definition in the early distinction between VAT and VAP. Retrospective single-center cohort, including all consecutive patients with a diagnosis of VAT (n = 70) or VAP (n = 136), during a 2-year period. Accuracy of sepsis criteria according to Sepsis-3, total SOFA and respiratory SOFA, calculated at time of microbiological sampling were assessed in differentiating VAT from VAP, and in predicting mortality on ICU discharge. Sensitivity and specificity of sepsis criteria were found respectively at 0.4 and 0.91 to distinguish VAT from VAP, and at 0.38 and 0.75 for the prediction of mortality in VA-LRTI. A total SOFA ≥ 6 and a respiratory SOFA ≥ 3 were identified as the best cut-offs for these criteria in differentiating VAT from VAP, with sensitivity and specificity respectively found at 0.63 and 0.69 for total SOFA, and at 0.49 and 0.7 for respiratory SOFA. Additionally, for prediction of mortality, a total SOFA ≥ 7 and a respiratory SOFA = 4 were identified as the best-cut-offs, respectively yielding sensitivity and specificity at 0.56 and 0.61 for total SOFA, and at 0.22 and 0.95 for respiratory SOFA. Sepsis criteria according to the Sepsis-3 definition show a high specificity but a low sensitivity for the diagnosis of VAP. Our results do not support the use of these criteria for the early diagnosis of VAP in patients with VA-LRTI.

Value of soluble triggering receptor expression on myeloid cells-1 level of alveolar fluid in early diagnosis of ventilator-associated pneumonia: a Meta-analysis

Serum soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) is a useful biomarker of bacterial infection. However, the diagnostic value of sTREM-1 of alveolar fluid in pulmonary infection is still unclear. This article aimed to explore the value of sTREM-1 of alveolar fluid in the early diagnosis of ventilator-associated pneumonia (VAP) by systematic review of relevant literatures. CNKI, Wanfang, VIP, PubMed/Medline and Embase databases were retrieved. Articles on diagnosis of VAP by sTREM-1 before June 30, 2019 were collected. QUADAS-2 scale provided by Cochrane Collaboration Network was used to evaluate the quality of diagnostic experiments. RevMan 5.3 and Stata 13.0 software were used to complete Meta-analysis. The levels of sTREM-1 between VAP and non-VAP patients were analyzed by Meta-analysis, and then diagnostic test Meta-analysis was conducted. Heterogeneity, sensitivity and publication bias were analyzed. A total of 24 articles were enrolled. QUADAS-2 scale indicated that the selected literature had low bias and high clinical adaptability. (1) In Meta-analysis of sTREM-1 level in alveolar fluid, 20 articles were selected and found to have high heterogeneity (I2 = 94.4%, P = 0.000). The random effects models were used for Meta-analysis. It was indicated that the sTREM-1 level in alveolar fluid of VAP group was significantly higher than that of non-VAP group with significant difference [standardized mean difference (SMD) was 1.47, 95% confidence interval (95%CI) was 1.00-1.95, Z = 6.14, P = 0.000]. By subgroup analysis and Meta-regression analysis, no source of heterogeneity was found. Sensitivity analysis suggested that the results of this Meta-analysis were robust and credible, and Begg funnel plot analysis showed that there was no significant publication bias (Z = 1.46, P = 0.143). (2) A total of 18 articles were included in the Meta-analysis of diagnostic experiments. Deek funnel plot showed publication bias (P = 0.012). The combined sensitivity was 0.87 (95%CI was 0.81-0.91), specificity was 0.80 (95%CI was 0.73-0.86), and diagnostic odds ratio (DOR) was 26 (95%CI was 13-50). Subgroup analysis of three different sources of alveolar fluid (bronchoalveolar lavage fluid, endotracheal aspiration fluid and exhaled ventilator condensate) showed that STREM-1 had a certain value in early diagnosis of VAP. The I2 of combined DOR was 35.4%, and I2 of sensitivity was 79.46%, I2 of specificity was 77.61%, suggesting heterogeneity in the selected literature. Subgroup analysis found that nationality, subject design, sample source, sample size and diagnostic "gold criteria" were related to heterogeneity, but not age. The area under synthetic receiver operating characteristic (SROC) curve (AUC) was 0.90 (95%CI was 0.87-0.92). The detection of sTREM-1 level in alveolar fluid can be used for the early diagnosis of VAP with high sensitivity and specificity. If combined with other biomarkers, it may have more diagnostic value.

Lung ultrasound score to monitor COVID-19 pneumonia progression in patients with ARDS.

COVID-19 pneumonia typically begins with subpleural ground glass opacities with progressive extension on computerized tomography studies. Lung ultrasound is well suited to this interstitial, subpleural involvement, and it is now broadly used in intensive care units (ICUs). The extension and severity of lung infiltrates can be described numerically with a reproducible and validated lung ultrasound score (LUSS). We hypothesized that LUSS might be useful as a tool to non-invasively monitor the evolution of COVID-19 pneumonia at the bedside. LUSS monitoring was rapidly implemented in the management of our COVID-19 patients with RT-PCR-documented COVID-19. The LUSS was evaluated repeatedly at the bedside. We present a graphic description of the course of LUSS during COVID-19 in 10 consecutive patients admitted in our intensive care unit with moderate to severe ARDS between March 15 and 30th. LUSS appeared to be closely related to the disease progression. In successfully extubated patients, LUSS decreased and was lower than at the time of intubation. LUSS increased inexorably in a patient who died from refractory hypoxemia. LUSS helped with the diagnosis of ventilator-associated pneumonia (VAP), showing an increased score and the presence of new lung consolidations in all 5 patients with VAPs. There was also a good agreement between CT-scans and LUSS as for the presence of lung consolidations. In conclusion, our early experience suggests that LUSS monitoring accurately reflect disease progression and indicates potential usefulness for the management of COVID-19 patients with ARDS. It might help with early VAP diagnosis, mechanical ventilation weaning management, and potentially reduce the need for X-ray and CT exams. LUSS evaluation is easy to use and readily available in ICUs throughout the world, and might be a safe, cheap and simple tool to optimize critically ill COVID-19 patients care during the pandemic.

A new scoring system for early diagnosis of ventilator-associated pneumonia: LUPPIS

IntroductionThe Clinical Pulmonary Infection Score (CPIS) based on chest X-ray has been developed to facilitate clinical diagnosis of ventilator-associated pneumonia (VAP); however, this scoring system has a low diagnostic performance. We developed the Lung Ultrasound and Pentraxin-3 Pulmonary Infection Score (LUPPIS) for early diagnosis of VAP and evaluated the performance of this new scoring system.Material and methodsIn a prospective study of 78 patients with suspected VAP, we assessed the detection accuracy of LUPPIS for pneumonia in adult patients. We also evaluated the diagnostic performance of pentraxin-3 (PTX-3) findings of infection. On the day of the study, lung ultrasound was performed, PTX-3 levels were determined, and an endotracheal aspirate was obtained for Gram staining and culture.ResultsNo significant differences were found between groups with respect to age, mechanical ventilation time, APACHE II score, or SOFA score (p > 0.05). Procalcitonin and PTX-3 levels were significantly higher in the VAP (+) group (p < 0.001 and p < 0.001, respectively). The threshold for LUPPIS in differentiating VAP (+) patients from VAP (–) patients was > 7. In predicting VAP, LUPPIS > 7 (sensitivity of 84%, specificity of 87.7%) was superior to CPIS > 6 (sensitivity of 40.1%, specificity of 84.5%).ConclusionsLUPPIS appears to provide better results in the prediction of VAP compared to CPIS, and the importance of lung ultrasound and PTX-3 is emphasized, which is a distinctive property of LUPPIS.

Lung Ultrasound for Early Diagnosis of Ventilator-Associated Pneumonia

AbstractBackground: Lung Ultrasound (LUS) has important role in diagnosis of different lung diseases so it can be used in diagnosis and early detection of Ventilator-Associated Pneu-monia (VAP).Aim of Study: Our aim is to evaluate the sensitivity and the specificity of lung ultrasound for early diagnosis of ventilator-associated pneumonia compared to chest X-ray.Patients and Methods: This study was carried out on 100 patients divided into two Groups (A & B), each one included 50 adult male and female patients with suspected VAP. In Group A (LUS), we searched for lung ultrasound findings as subpleural consolidation, lobar consolidation, and dynamic arborescent/linear air bronchogram while in Group B (CXR), we searched for chest X-ray findings as lung infiltrates and air bronchogram. In both groups, Endotracheal Aspirates (EA) was collected for direct gram stain examination (EAgram) and culture (EAquant). LUS findings were analyzed in scores as the clinical-LUS score (Ventilator-associated Pneumonia Lung Ultrasound Score [VPLUS]) which was calculated as follows: ³2 areas with subpleural consolidations, 1 point; ³1 area with dynamic arborescent/linear air bronchogram, 2 points; and purulent EA, 1 point. Positive direct gram stain examination (EAgram) or positive culture (EAquant) which had 2 points were added to VPLUS to be VPLUS EAgram and VPLUS EAquant.Results: The sensitivity and the specificity of lung ultra-sound findings in Group A (LUS) were higher than chest X-ray findings Group B (CXR) as presence of ultrasound signs in Group A (LUS) (lobar/hemilobar consolidations, dynamic air bronchogram, subpleural consolidations) separate or combined gave us sensitivity 97%, lobar or hemilobar consol-idations had sensitivity 94%, presence of dynamic air bron-chogram or subpleural consolidations gave us sensitivity 94%, VPLUS-EAquant ³3 gave us sensitivity 94%. The best spe-cificity was found also in Group A as (air bronchogram + subpleural consolidations + positive culture or positive gram stain examination) gave us the highest specificity 100%, combination of (dynamic air bronchogram and subpleural consolidations) gave us high specificity 94%, combination of (lobar/hemilobar consolidations, dynamic air bronchogram and subpleural consolidations) gave us also high specificity 94%, (VPLUS-EAquant ³4, VPLUS-EAgram ³4 and VPLUS ³3) had specificity 94%. On the other hand, signs of chest X-ray in Group B had lower sensitivity and specificity com-pared to lung ultrasound in Group A as chest X-ray infiltrates gave us sensitivity 53%, specificity 25%, air bronchogram had sensitivity 33%, specificity 40%, presence of (chest X-ray infiltraes, air bronchogram) separate or combined gave us sensitivity 57%, specificity 25%.Conclusion: The sensitivity and specificity of lung ultra-sound were higher than chest xray, so lung ultrasound is better than chest X-ray for early diagnosis of VAP.

Lung ultrasound for diagnosis and monitoring of ventilator-associated pneumonia.

Ventilator-associated pneumonia (VAP) is the most frequent nosocomial infection in intensive care units (ICU) and is associated with increased mortality, use of antimicrobials, longer mechanical ventilation, and higher healthcare costs. Lung ultrasonography (LUS) can be used at the bedside and gained widespread acceptance in ICU. Although the visualization of a single LUS sign cannot be considered specific for a diagnosis, clinically-driven LUS examination in particular setting and clinical conditions allow ruling in or out quickly and accurately several causes of acute respiratory failure. This article reviews LUS signs for VAP diagnosis and summarizes the studies testing LUS for VAP diagnosis and monitoring. Many VAP occurs in already injured regions, thus presence of lobar consolidation is not enough to affirm VAP. However, a linear/arborescent air-bronchogram confirms the diagnosis of VAP with a good specificity, a normal LUS rules out the diagnosis of VAP (in experimented hands). LUS, thanks to its bedside ready availability, has the potential to become a key tool in early VAP diagnosis. LUS could ideally represent the decision-making tool for antimicrobial therapy administration in the timeframe of the technical time required for bronchoalveolar lavage analysis. A systematic approach for diagnosis and monitoring of VAP with LUS is also proposed in this review. But specific data on LUS specificity and sensitivity for the diagnosis of VAP are still lacking and should be investigated.

Pentraxin3 as an early marker in the diagnosis of ventilator-associated pneumonia

Objective The aim of this study was to assess the role of pentraxin3 (PTX3) in the early diagnosis of ventilator-associated pneumonia (VAP). Background The early diagnosis of VAP remains a challenge because the clinical signs and symptoms lack sensitivity and specificity and because microbiological analysis and identification of organisms may take 48–72 h. Patients and methods This prospective randomized study was carried out on 40 patients diagnosed with VAP using clinical pulmonary infection score in Menoufia University Hospital's ICU. We measured the level of PTX3 in serum and bronchoalveolar lavage and the level of C-reactive protein within 24 h from intubation and mechanical ventilation and after the onset of VAP diagnosed using clinical pulmonary infection score more than 6. Results The study showed that VAP was diagnosed in 31 patients; 30 had bronchoalveolar lavage PTX3 level of at least 6 ng/ml with 96.7% sensitivity, 100% specificity, 100% positive predictive value (PPV), and 90% negative predictive value (NPV) for pneumonia confirmed using area under the receiver operating characteristic curve (AUCROC) analysis [AUCROC= 0.966, SE = 0.006, 95% confidence interval (CI)=0.985–1, P Conclusion Alveolar PTX3 level of at least 6 ng/ml is discriminative for microbiologically confirmed VAP; serum PTX3 is also sensitive but to a lower extent than alveolar PTX3.

Respiratory mechanics, ventilator-associated pneumonia and outcomes in intensive care unit.

AIMTo evaluate the predictive capability of respiratory mechanics for the development of ventilator-associated pneumonia (VAP) and mortality in the intensive care unit (ICU) of a hospital in southern Brazil.METHODSA cohort study was conducted between, involving a sample of 120 individuals. Static measurements of compliance and resistance of the respiratory system in pressure-controlled ventilation (PCV) and volume-controlled ventilation (VCV) modes in the 1st and 5th days of hospitalization were performed to monitor respiratory mechanics. The severity of the patients’ illness was quantified by the Acute Physiology and Chronic Health Evaluation II (APACHE II). The diagnosis of VAP was made based on clinical, radiological and laboratory parameters.RESULTSThe significant associations found for the development of VAP were APACHE II scores above the average (P = 0.016), duration of MV (P = 0.001) and ICU length of stay above the average (P = 0.003), male gender (P = 0.004), and worsening of respiratory resistance in PCV mode (P = 0.010). Age above the average (P < 0.001), low level of oxygenation on day 1 (P = 0.003) and day 5 (P = 0.004) and low lung compliance during VCV on day 1 (P = 0.032) were associated with death as the outcome.CONCLUSIONThe worsening of airway resistance in PCV mode indicated the possibility of early diagnosis of VAP. Low lung compliance during VCV and low oxygenation index were death-related prognostic indicators.

Utility of chest ultrasonography and pulmonary infection score in early diagnosis of ventilator-associated pneumonia

Background Ventilator-associated pneumonia (VAP) remains a morbid and prevalent problem throughout the world. Lung ultrasound (LUS) is increasingly being used at the bedside for assessing alveolar-interstitial syndrome, lung consolidation, pneumothorax, and pleural effusion. Purpose The aim was to focus on the use of bedside LUS alone and in association with the clinical pulmonary infection score (CPIS) in early diagnosis of VAP, to describe the sonographic features, to compare between LUS and portable chest radiography (CXR) in early diagnosis of ventilator-associated pneumonia (VAP), and weather LUS affects the prognostic outcomes of VAP. Patients and methods A total of 40 patients with suspected VAP were enrolled. Portable CXR, LUS, and computed tomography scan (gold standard) were performed. The CPIS was calculated for early and reliable diagnosis of VAP. The prognostic outcomes were highlighted. Results Among forty VAP-suspected cases, 30 (75%) were confirmed using computed tomography (gold standard). LUS imaging of VAP cases diagnosed 28 (70%) with consolidation, 89.3% of them with air bronchogram, and 32.5% of them with pleural effusion. Validity for early VAP diagnosis using portable CXR demonstrated 86.7, 100, 100, 71.4, and 90%; ultrasound 93.3, 100, 100, 83.3, and 95%; whereas CPI score 50, 90, 93.8, 62.5, and 60% regarding sensitivity, specificity, positive predictive value, negative predictive value, and accuracy, respectively. CPIS combined with LUS revealed higher sensitivity (96.7%) and accuracy (97.5%). Low CPIS less than or equal to 6, modes of mechanical ventilation (continuous positive airway pressure and biphasic positive airway pressure), shorter duration of respiratory support, LUS imaging of air bronchogram and simple pleural effusion were significantly associated with improved outcomes of VAP cases. The duration of mechanical ventilation and early detection of air bronchogram by LUS were the independent mortality predictors with odds ratio of 2.4 and 3.11 and 95% CI of 1.56–4.55 and 1.8–17.66, respectively. Conclusion LUS was a reliable tool for early VAP diagnosis at the bedside. Combination approach increases the prognostic and diagnostic accuracy of LUS in VAP.

Pentraxin 3 as an early marker in diagnosis of ventilator associated pneumonia

ObjectiveTo assess the role of pentraxin 3 (PTX3) in early diagnosis of ventilator associated pneumonia (VAP). BackgroundThe early diagnosis of VAP remains a challenge because the clinical signs and symptoms lack sensitivity and specificity and microbiological analysis and identification of organisms may take 48–72 h. MethodsThis prospective randomized study was conducted on forty patients diagnosed with VAP by clinical pulmonary infection score (CPIS) admitted in the intensive care unit (ICU) of Menoufia University Hospitals. We measured the level of PTX 3 in serum and bronchoalveolar lavage (BAL) and the level of CRP within 24 h from intubation and mechanical ventilation then after the onset of VAP diagnosed by CPIS > 6. ResultsVAP was diagnosed in 31 patients; 30 had BAL PTX 3 level ≥6 ng/ml with 96.7% sensitivity, 100% specificity,100% positive predictive value and 90% negative predictive value for pneumonia confirmed by Area under the receiver operating characteristic curve (AUCROC) analysis (AUCROC = 0.966, SE = .006, 95% CI = 0.985–1, P < .0001) and 27 had serum PTX 3 level ≥6 ng/ml with 87% sensitivity, 88.8% specificity, 96.4% positive predictive value and 66.6% negative predictive value for pneumonia confirmed by (AUCROC) analysis (AUCROC = 0.842, SE = .104, 95% CI = .639–1, p = .002) and 24 had CRP level ≥12 mg/l with 77.4% sensitivity, 33.3% specificity, 80% positive predictive value and 30% negative predictive value for pneumonia confirmed by (AUCROC) analysis (AUCROC = 0.590, SE = .1, 95% CI = .39–.79, p = .418). ConclusionBAL PTX3 level ≥6 ng/ml is discriminative for microbiologically confirmed VAP, serum PTX3 is also sensitive but less than BAL PTX3.

Endotracheal Aspirate Microscopy, Cultures and Endotracheal Tube Tip Cultures for Early Prediction of Ventilator Associated Pneumonia in Neonates.

To evaluate the utility of endotracheal aspirate microscopy, culture and endotracheal tube tip culture for early diagnosis of ventilator-associated pneumonia in neonates. Inborn ventilated neonates were followed-up for ventilator-associated pneumonia using Center for Disease Control and Prevention (CDC) criteria. Endotracheal aspirate microscopy, culture and endotracheal tube tip cultures were performed. Ventilator-associated pneumonia occurred in 28/68 (41%) neonates as per CDC criteria. Endotracheal aspirate microscopy (≥5 polymorphonuclear cells per high power field) and endotracheal aspirate culture had 78.6% and 75% sensitivity, 87.5% and 90% specificity, positive predictive value of 81.5% and 84%, and negative predictive value of 85.4% and 83.72%, respectively. Mean (SD) time of result of microscopy and endotracheal aspirate culture was 55.7 (4.3) h and 108.3 (19.7) h, respectively in comparison to diagnosis made at 143.5 (23.3) h, as per CDC criteria. Endotracheal aspirate microscopic examination and culture can be supportive in objective diagnosis of ventilator-associated pneumonia with an added advantage of earlier prediction.

English

Ventilator associated pneumonia (VAP) is a common complication of ventilatory support for patients with acute respiratory failure, currently related to high mortality rate. Therefore, this complication of mechanical ventilation requires a prompt diagnosis and adequate antibiotic treatment. The study aimed to investigate the role of endotracheal aspirate (ETA) surveillance cultures in identifying the aetiology of VAP earlier. The study was conducted over a period of 12 months and included 152 patients under mechanical ventilation for &gt;48 h from different ICUs of Assiut University Hospitals. Quantitative cultures of ETA at threshold of 105cfu/ml were performed. The organisms were primarily identified by colony morphology, microscopy of Gram stain and standard biochemical tests. The antibiotic resistance pattern of the isolated bacteria was determined by Kirby-Bauer disk diffusion method. VAP was suspected in 92/152 patients (60.53%). Microbiological support for VAP was obtained by ETA in 90 patients. Positive cultures occurred in 88 patients, the infection was polymicrobial in 50 (54.34%) of cultures.&nbsp; Major isolated pathogenic bacteria were gram negative (54.79%); Klebsiella species was the commonest organism (23.29 %). Gram positive bacteria were detected in 42.47% of the cultures; methicillin resistant Staphylococcus aureus (MRSA) was the predominant organism (24.40%). Gram negative bacteria showed high resistance to penicillins, cephalosporins and quinolones, the least resistance was to imipenem. Mortality was higher in VAP group (47.8%) than non VAP (30%). It is indicated that quantitative cultures of ETA is a useful method for early diagnosis of VAP with subsequent proper selection of adequate therapy. &nbsp; Key words: Endotracheal aspirate, quantitative cultures, ventilator-associated pneumonia.