Ventilator associated pneumonia in the ICU: where has it gone?

Effectiveness of supervised implementation of an oral health care protocol on ventilator-associated pneumonia patients in intensive care units: a double-blind multicenter randomized controlled trial

Background

The available scientific evidence suggests a significant association between oral bacteria and the incidence of ventilator-associated pneumonia (VAP).

Aims

The aim of this study was to determine the effectiveness of an oral health protocol in the prevention of ventilator-associated pneumonia.

Methods

In this multi-center RCT, conducted in the intensive care units of neurological patients in three general teaching hospitals of two provinces located in the west of the Iran, a consecutive sample of 200 intubated patients were initially recruited. Patients were randomly allocated to the intervention (received oral health care based on evidence-based oral health protocol) or control (routine oral health care) groups. Both groups received their prescribed treatment regimen for seven consecutive days. The percentage of VAP diagnoses as main outcome assessed using clinical pulmonary infection score (CPIS).

Findings

The rate of VAP in the intervention and control groups was 5% and 64%, respectively. The intervention reduced the risk of VAP by 97% and this difference was statistically significant (P <0.001). The chance of VAP occurrence in patients with lower levels of consciousness in univariate and multivariate analysis was significantly higher (OR: 2.38; 95%CI: 1.11-5.26) P <0.05).

Conclusion

The results of our study suggest that the use of a dynamic supervised oral health care guideline is more effective than the routinely used protocols in the intensive care units of hospitals.

The Current Epidemiological Landscape of Ventilator-associated Pneumonia in the Intensive Care Unit: A Multicenter Prospective Observational Study in China

Background

Ventilator-associated pneumonia (VAP) is among the most important hospital-acquired infections in the intensive-care unit setting. However, clinical data regarding the epidemiology of VAP in China are limited.

Methods

A multicenter, longitudinal, observational study was performed from March 2013 to December 2015 to prospectively collect data on patients diagnosed with VAP. Specifically, patients supported by invasive mechanical ventilation for longer than 48 hours were included. Clinical data were recorded for each VAP patient. The exact pathogen distribution and the incidence of VAP were calculated. Risk factors associated with mortality were analyzed using univariate and multivariate regression analyses.

Results

A total of 2492 patients received mechanical ventilation for longer than 48 hours and were enrolled in the study. A total of 129 (5.0%) patients fulfilled the VAP criteria, and 38 (29.5%) patients were diagnosed with early-onset VAP. The incidence of VAP was 4.5 per 1000 ventilation days, with a 28-day mortality rate of 45%. Individual pathogens, including 115 bacteria and 2 fungi, were identified in 117 (90.7%) enrollees, and 87 (75.7%) bacteria were multidrug-resistant organisms. Acinetobacter baumannii, Klebsiella pneumoniae, and Pseudomonas aeruginosa were the most commonly detected pathogens causing VAP. No difference in the distribution of pathogens was observed between early- and late-onset VAP or between surviving and non-surviving patients. Multivariate regression revealed that older ages and Sequential Organ Failure Assessment Scores were correlated with increased 28-day mortality rates.

Conclusions

High pathogen resistance and mortality were found in both early- and late-onset VAP.

Clinical Trials Registration

NCT01943331.

Efficacy of antibiotic prophylaxis against ventilator-associated pneumonia

Ventilator-associated pneumonia (VAP) is one of the most important problems of intensive care units. Eighty-four neurologic patients with acute stroke (Glasgow Coma Score ≤8) were entered into a double-blind clinical trial. Patients in the intervention group received piperacillin-tazobactam 4 g/0.5 g at the time of intubation and 12 h later. The incidences of early-onset (within four days of intubation) and late-onset VAP were 9.2 and 26.9 episodes per 1000 days of mechanical ventilation in the intervention and control groups, respectively (odds ratio: 0.217; 95% confidence interval: 0.056-0.085; P = 0.028). Administration of prophylactic piperacillin-tazobactam may reduce early-onset VAP, but the benefit does not extend to late-onset VAP.

Role of rifampin for the treatment of bacterial infections other than mycobacteriosis

OBJECTIVES

Rifampin was initially approved for the treatment of tuberculosis. Because of its low toxicity, broad-spectrum activity, and good bioavailability, rifampin is now commonly administered as combination antimicrobial therapy for the treatment of various infections caused by organisms other than mycobacteria. This review summarizes the most recent clinical studies on the use of rifampin combinations for treating four common non-mycobacterial infections: acute bacterial meningitis, infective endocarditis and bacteraemia, pneumonia, and biofilm-related infections.

METHODS

We performed a literature search of clinical studies published in English from January 2005 to June 2016 using the PubMed database with the search terms "rifampin" with "meningitis" or "infective endocarditis and bacteraemia" or "pneumonia" or "prosthetic joint infections.

RESULTS

Current evidence to support a rifampin combination therapy as a treatment for non-mycobacterial infections was largely based on in vitro/in vivo studies and non-comparable retrospective case series. Additionally, controlled clinical trials that directly compared outcomes resulting from rifampin treatment versus treatment without rifampin were limited.

CONCLUSIONS

Rifampin combination therapy appears promising for the treatment of non-mycobacterial infections. However, further definitive clinical trials are necessary to validate its use because the risk of adverse drug-drug interactions and of the emergence of rifampin resistance during treatment may outweigh the potential benefits.

Diagnostic Efficacy of Serum Amyloid A Protein and Soluble Intercellular Adhesion Molecule 1 in Pediatric Ventilator-Associated Pneumonia

Objectives:

Study of inflammatory biomarkers which may aid in early detection of ventilator-associated pneumonia (VAP) in children and predicting their outcome.

Patients:

Thirty-five children, aged 2 months to 13 years, needed mechanical ventilation (MV) for more than 48 hours due to causes other than pneumonia.

Methods:

Measurement of serum amyloid A (SAA) protein, soluble intercellular adhesion molecule 1 (sICAM-1), and C-reactive protein (CRP), modified clinical pulmonary infection score (CPIS) and performing culture of endotracheal aspirate at the start and on the third day of MV.

Results:

Ventilator-associated pneumonia was diagnosed by CPIS in 6 (17.1%) of 35 patients. On the third day of MV, there was a significant increase in serum mean levels of SAA, sICAM-1, and CRP in comparison to the start of MV ( P = .005, .004, and .01, respectively). Three (50%) of 6 patients with VAP died, while 4 (14.28%) of 28 patients without VAP died. The sensitivity of serum SAA, sICAM-1, and CPIS were 100% for predicting VAP, while specificity was highest for CPIS (96.55%) followed by SAA (93.1%). Combination of CPIS and SAA increased the specificity to 100%. For predicting nonsurvival, serum SAA and sICAM-1 had a sensitivity of 100% and a specificity of 92.86% and 89.29%, respectively.

Conclusion:

Serum amyloid A and sICAM-1 may be considered as reliable markers for detection of VAP. Combination of serum SAA with CPIS increased the specificity to 100%. Measurement of SAA in patients with VAP also had a good predictive value for nonsurvival in such patients.

Impact of tapered-cuff tracheal tube on microaspiration of gastric contents in intubated critically ill patients: a multicenter cluster-randomized cross-over controlled trial

PURPOSE

Studies on the impact of tapered-cuff tracheal tubes on rates of microaspiration and ventilator-associated pneumonia (VAP) in intubated patients have reported conflicting results. The aim of this study was to determine the influence of this shape of tracheal cuff on abundant microaspiration of gastric contents in critically ill patients.

METHODS

All patients intubated in the intensive care unit (ICU) and requiring mechanical ventilation for at least 48 h were eligible for this multicenter cluster-randomized controlled cross-over open-label study. The primary outcome was abundant microaspiration of gastric contents, defined by the presence of pepsin at significant level in >30% of tracheal aspirates. Quantitative measurement of pepsin and salivary amylase was performed in all tracheal aspirates during the 48 h following enrollment.

RESULTS

A total of 326 patients were enrolled in the ten participating ICUs (162 in the PVC tapered-cuff group and 164 in the standard-cuff group). Patient characteristics were similar in the two study groups. The proportion of patients with abundant microaspiration of gastric contents was 53.5% in the tapered-cuff and 51.0% in the standard-cuff group (odds ratio 1.14, 95% CI 0.72-1.82). While abundant microaspiration of oropharyngeal secretions was not significantly different (77.4 vs 68.6%, p = 0.095), the proportion of patients with tracheobronchial colonization was significantly lower (29.6 vs 43.3%, p = 0.01) in the tapered-cuff than in the standard-cuff group. No significant difference between the two groups was found for other secondary outcomes, including ventilator-associated events and VAP.

CONCLUSIONS

This trial showed no significant impact of tapered-cuff tracheal tubes on abundant microaspiration of gastric contents.

TRIAL REGISTRATION

ClinicalTrials.gov, number NCT01948635.

Individualized antibiotic therapy in patients with ventilator-associated pneumonia

The optimal duration of the treatment of ventilator-associated pneumonia (VAP) is still the subject of debate. While 1 week treatment has been reported as possibly sufficient, patients generally receive antibiotic therapy for 10 to 14 days. The purpose of our study was to investigate whether length of treatment in patients with VAP can be reduced with an individualized therapeutic strategy. The study was performed prospectively with patients diagnosed with VAP in our hospital's intensive care units between 1 January and 31 December 2015. Duration of antibiotic therapy was determined with 5 day clinical evaluation according to previously established criteria. Patients were divided into two groups depending on length of treatment, short (7-10 days) and long treatment (>10 days). Nineteen patients received 7 to 10 day antibiotic therapy, and 30 received >10 day antibiotic therapy. Demographic and clinical characteristics, Glasgow Coma Scale score, CPIS and the PaO2/FiO2 ratio at the time of diagnosis of VAP were statistically similar between the two groups (P>0.05). A second VAP attack occurred post-treatment in three patients receiving short-term treatment and in four receiving long-term treatment (P=0.561). The numbers of antibiotic-free days were 15.6±6.2 in the short-term treatment group and 8.3±7.5 in the long-term group (P<0.0001). One of the patients receiving short-term treatment died within 28 days after treatment, and four of the patients receiving long-term treatment (P=0.348) did so. The most commonly observed micro-organisms in both groups were Acinetobacterbaumannii and Pseudomonasaeruginosa. Short-term treatment can be administered in cases with early clinical and laboratory response started on VAP treatment by considering individual characteristics and monitoring fever, CPIS, the PaO2/FiO2 ratio, C-reactive protein and procalcitonin values.

BreathDx - molecular analysis of exhaled breath as a diagnostic test for ventilator-associated pneumonia: protocol for a European multicentre observational study

BACKGROUND

The diagnosis of ventilator-associated pneumonia (VAP) remains time-consuming and costly, the clinical tools lack specificity and a bedside test to exclude infection in suspected patients is unavailable. Breath contains hundreds to thousands of volatile organic compounds (VOCs) that result from host and microbial metabolism as well as the environment. The present study aims to use breath VOC analysis to develop a model that can discriminate between patients who have positive cultures and who have negative cultures with a high sensitivity.

METHODS/DESIGN

The Molecular Analysis of Exhaled Breath as Diagnostic Test for Ventilator-Associated Pneumonia (BreathDx) study is a multicentre observational study. Breath and bronchial lavage samples will be collected from 100 and 53 intubated and ventilated patients suspected of VAP. Breath will be analysed using Thermal Desorption - Gas Chromatography - Mass Spectrometry (TD-GC-MS). The primary endpoint is the accuracy of cross-validated prediction for positive respiratory cultures in patients that are suspected of VAP, with a sensitivity of at least 99% (high negative predictive value).

DISCUSSION

To our knowledge, BreathDx is the first study powered to investigate whether molecular analysis of breath can be used to classify suspected VAP patients with and without positive microbiological cultures with 99% sensitivity.

TRIAL REGISTRATION

UKCRN ID number 19086, registered May 2015; as well as registration at www.trialregister.nl under the acronym 'BreathDx' with trial ID number NTR 6114 (retrospectively registered on 28 October 2016).

Is inhaled colistin beneficial in ventilator associated pneumonia or nosocomial pneumonia caused by Acinetobacter baumannii?

BACKGROUND

In the present study, our objective was to evaluate and compare the clinical and microbiological results in patients receiving systemic and systemic plus inhaled colistin therapy due to nosocomial pneumonia (NP) or ventilator associated pneumonia (VAP) caused by Acinetobacter baumannii.

METHODS

A retrospective matched case-control study was performed at the ICUs at Izmir Katip Celebi University Ataturk Training and Research Hospital from January 2013 to December 2014. Eighty patients who received only systemic colistin were matched 43 patients who received systemic colistin combined with inhaled therapy.

RESULTS

In 97.6 % of the patients colistin was co-administered with at least one additional antibiotic. The most frequently co-administered antibiotics were carbapenems (79.7 %). The patient groups did not differ significantly in terms of the non-colistin antibiotics used for treatment (p > 0.05). Acute renal injury was observed in 53.8 % and 48.8 % of the patients who received parenteral colistin or parenteral plus inhaler colistin, respectively (p = 0.603). There were no significant differences between the groups in terms of clinical success (p = 0.974), clinical failure (p = 0.291), or recurrence (p = 0.094). Only, a significantly higher partial clinical improvement rate was observed in the systemic colistin group (p = 0.009). No significant differences between the two groups in terms of eradication (p = 0.712), persistence (p = 0.470), or recurrence (p = 0.356) rates was observed. One-month mortality rate was similar in systemic (47.5 %) and systemic plus inhaled (53.5 %) treatment groups (p = 0.526).

CONCLUSIONS

Our results suggest that combination of inhaled colistin with intravenous colistin had no additional therapeutic benefit in terms of clinical or microbiological outcomes.

Oral health promotion in patients with chronic renal failure admitted in the Intensive Care Unit

Oral hygiene deficiency is common in patients treated in ICUs and it enables biofilm colonization by microorganisms that lead to respiratory infections. A 30‐year‐old female patient with chronic renal failure was hospitalized. Dental procedures were performed in the ICU and contributed to the patient's health after a few days.

High-throughput sequencing of 16S rDNA amplicons characterizes bacterial composition in bronchoalveolar lavage fluid in patients with ventilator-associated pneumonia

Ventilator-associated pneumonia (VAP) is a life-threatening disease that is associated with high rates of morbidity and likely mortality, placing a heavy burden on an individual and society. Currently available diagnostic and therapeutic approaches for VAP treatment are limited, and the prognosis of VAP is poor. The present study aimed to reveal and discriminate the identification of the full spectrum of the pathogens in patients with VAP using high-throughput sequencing approach and analyze the species richness and complexity via alpha and beta diversity analysis. The bronchoalveolar lavage fluid samples were collected from 27 patients with VAP in intensive care unit. The polymerase chain reaction products of the hypervariable regions of 16S rDNA gene in these 27 samples of VAP were sequenced using the 454 GS FLX system. A total of 103,856 pyrosequencing reads and 638 operational taxonomic units were obtained from these 27 samples. There were four dominant phyla, including Proteobacteria, Firmicutes, Actinobacteria, and Bacteroidetes. There were 90 different genera, of which 12 genera occurred in over ten different samples. The top five dominant genera were Streptococcus, Acinetobacter, Limnohabitans, Neisseria, and Corynebacterium, and the most widely distributed genera were Streptococcus, Limnohabitans, and Acinetobacter in these 27 samples. Of note, the mixed profile of causative pathogens was observed. Taken together, the results show that the high-throughput sequencing approach facilitates the characterization of the pathogens in bronchoalveolar lavage fluid samples and the determination of the profile for bacteria in the bronchoalveolar lavage fluid samples of the patients with VAP. This study can provide useful information of pathogens in VAP and assist clinicians to make rational and effective therapeutic decisions.