The diagnostic dilemma of ventilator-associated pneumonia in critically ill children

Diagnostic Stewardship of Endotracheal Aspirate Cultures in Hospitalized Children With Artificial Airways: Expert Consensus Statements From the BrighT STAR (Testing STewardship for Antibiotic Reduction) Respiratory Collaborative

OBJECTIVE

To develop consensus statements that clinicians can apply to standardize and optimize endotracheal aspirate culture (EAC) practices in hospitalized children with artificial airways who are being evaluated for a bacterial lower respiratory tract infection (LRTI).

DESIGN

A modified Delphi consensus process with expert panelists. Panelists conducted a "pre-survey" to itemize respiratory signs of bacterial LRTI. Round 1 included a literature summary and electronic survey of 50 potential statements sent to all panelists. We surveyed panelist opinions using a 5-point Likert scale. We grouped the responses "agree" and "strongly agree" as agreement. Consensus was defined as statements reaching greater than 75% agreement. Round 2 was moderated by an independent expert in consensus methodology. Panelists convened in person in November 2023, discussed any statements not reaching consensus or statements with disagreement, were resurveyed, and finalized statements in real time.

SETTING

Electronic surveys and in-person meetings in Baltimore, MD.

SUBJECTS

The BrighT STAR (Testing STewardship for Antibiotic Reduction) collaborative along with U.S.-based pediatric experts in critical care, cardiac critical care, infectious diseases, hospital medicine, otolaryngology, pulmonology, and clinical microbiology.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Thirty-eight of 40 invited panelists completed round 1. Of 50 initial statements, 28 reached greater than 90% agreement, 16 had 75-89% agreement, and 6 had less than 75% agreement. Twenty-eight statements were finalized. Round 2 involved 37 panelists: 23 statements were discussed, of which 17 reached an agreement and 6 did not reach consensus. We concluded with 30 statements and 15 sub-statements, 37 of which had greater than 90% agreement. Final statements informed a clinical decision support algorithm.

CONCLUSIONS

The BrighT STAR collaborative group achieved consensus for 45 clinical practice statements that can standardize EAC practices, including indications to consider for testing, reasons to defer, optimal specimen collection, and result interpretation. These statements offer a starting point for clinical decision support tools and diagnostic stewardship programs for EAC practices in patients with artificial airways.

Management of Ventilator-Associated Pneumonia Caused by Pseudomonas and Acinetobacter Organisms in a Pediatric Center: A Randomized Controlled Study

A dangerous infection contracted in hospitals, ventilator-associated pneumonia is frequently caused by bacteria that are resistant to several drugs. It is one of the main reasons why patients in intensive care units become ill or die. This research aimed to determine the most effective empirical therapy of antibiotics for better ventilator-associated pneumonia control and to improve patient outcomes by using the minimal inhibitory concentration method and the Ameri-Ziaei double antibiotic synergism test and by observing the clinical responses to both single and combination therapies. Patients between the ages of one month and twelve who had been diagnosed with ventilator-associated pneumonia and had been on mechanical ventilation for more than 48 h were included in the study, which was carried out in the Pediatric Intensive Care Unit at Cairo University's Hospital. When ventilator-associated pneumonia is suspected, it is critical to start appropriate antibiotic therapy as soon as possible. This is especially important in cases where multidrug-resistant Gram-negative infections may develop. Although using Polymyxins alone or in combination is effective, it is important to closely monitor their administration to prevent resistance from increasing. The combination therapy that showed the greatest improvement was a mix of aminoglycosides, quinolones, and β-lactams. A combination of aminoglycosides and dual β-lactams came next. Although the optimal duration of antibiotic treatment for ventilator-associated pneumonia is still unknown, treatments longer than seven days are usually required to eradicate MDR P. aeruginosa or A. baumannii completely.

Variations and National Perspectives on Evaluation and Management of Ventilator-Associated Pneumonia in Neonatal Intensive Care Units: An In-Depth Survey Analysis

Introduction Infants in the neonatal intensive care unit (NICU) are vulnerable to ventilator-associated pneumonia (VAP), which increases their morbidity and mortality. There is a significant overlap of clinical features of neonatal VAP with other pulmonary pathologies, particularly in preterm infants, which can make the definitive diagnosis and management of VAP challenging. Objective Our study surveyed NICU providers across the United States to understand the perspectives and variations in neonatal VAP diagnostic and management practices. Methods The REDCap survey was distributed to the actively practicing members of the Section on Neonatal-Perinatal Medicine (SoNPM) of the American Academy of Pediatrics (AAP). We used descriptive statistics to analyze the data from the respondents. Results Of 254 respondents, the majority (86.6%, 220) were neonatologists and had a relatively even geographical distribution. Most (75.9%, 193) stated that they would perform a gram stain and respiratory culture as part of a sepsis workup irrespective of the patient's duration on invasive mechanical ventilation (IMV); 224 (88.2%) of providers preferred the endotracheal aspiration (ETA) technique to collect specimens. In cases where a positive respiratory culture was present, VAP (52.4%, 133) was the predominantly assigned diagnosis, followed by pneumonia (27.2%, 69) and ventilator-associated tracheitis (VAT) (9.8%, 25). Respondents reported a prescription of intravenous gentamicin (70%, 178) and vancomycin (41%, 105) as the initial empiric antibiotic drugs, pending final respiratory culture results. Most respondents (55.5%, 141) opted for seven days of antibiotics duration to treat VAP. The reported intra-departmental variation among colleagues in acquiring respiratory cultures and prescribing antibiotics for VAP was 48.8% (124) and 37.4% (95), respectively, with slightly more than half (53.5%, 136) of providers reporting having VAP prevention guidelines in their units. Conclusion The survey study revealed inconsistencies in the investigation, diagnostic nomenclature, choice of antibiotic, and treatment duration for neonatal VAP. Consequently, there is a pressing need for further research to establish a clear definition and evidence-based criteria for VAP.

Lung ultrasound: A potential tool in the diagnosis of ventilator-associated pneumonia in pediatric intensive care units

PURPOSE

Ventilator-associated pneumonia (VAP) is a common healthcare-associated infection in pediatric intensive care unit (PICU), increasing mortality, antibiotics use and duration of ventilation and hospitalization. VAP diagnosis is based on clinical and chest X-ray (CXR) signs defined by the 2018 Center for Disease Control (gold standard). However, CXR induces repetitive patients' irradiation and technical limitations. This study aimed to investigate if lung ultrasound (LUS) can substitute CXR in the VAP diagnosis.

METHODS

A monocentric and prospective study was conducted in a French tertiary care hospital. Patients under 18-year-old admitted to PICU between November 2018 and July 2020 with invasive mechanical ventilation for more than 48 h were included. The studied LUS signs were consolidations, dynamic air bronchogram, subpleural consolidations (SPC), B-lines, and pleural effusion. The diagnostic values of each sign associated with clinical signs (cCDC) were compared to the gold standard approach. LUS, chest X-ray, and clinical score were performed daily.

RESULTS

Fifty-seven patients were included. The median age was 8 [3-34] months. Nineteen (33%) children developed a VAP. In patients with VAP, B-Lines, and consolidations were highly frequent (100 and 68.8%) and, associated with cCDC, were highly sensitive (100 [79-100] % and 88 [62-98] %, respectively) and specific (95.5 [92-98] % and 98 [95-99] %, respectively). Other studied signs, including SPC, showed high specificity (>97%) but low sensibility (<50%).

CONCLUSION

LUS seems to be a powerful tool for VAP diagnosis in children with a clinical suspicion, efficiently substituting CXR, and limiting children's exposure to ionizing radiations.

Ventilator-Associated Pneumonia in the Neonatal Intensive Care Unit-Incidence and Strategies for Prevention

The second most prevalent healthcare-associated infection in neonatal intensive care units (NICUs) is ventilator-associated pneumonia (VAP). This review aims to update the knowledge regarding the incidence of neonatal VAP and to summarize possible strategies for prevention. The VAP incidence ranges from 1.4 to 7 episodes per 1000 ventilator days in developed countries and from 16.1 to 89 episodes per 1000 ventilator days in developing countries. This nosocomial infection is linked to higher rates of illness, death, and longer hospital stays, which imposes a substantial financial burden on both the healthcare system and families. Due to the complex nature of the pathophysiology of VAP, various approaches for its prevention in the neonatal intensive care unit have been suggested. There are two main categories of preventative measures: those that attempt to reduce infections in general (such as decontamination and hand hygiene) and those that target VAP in particular (such as VAP care bundles, head of bed elevation, and early extubation). Some of the interventions, including practicing good hand hygiene and feeding regimens, are easy to implement and have a significant impact. One of the measures that seems very promising and encompasses a lot of the preventive measures for VAP are the bundles. Some preventive measures still need to be studied.

A Survey of PICU Clinician Practices and Perceptions regarding Respiratory Cultures in the Evaluation of Ventilator-Associated Infections in the BrighT STAR Collaborative

OBJECTIVES

To characterize respiratory culture practices for mechanically ventilated patients, and to identify drivers of culture use and potential barriers to changing practices across PICUs.

DESIGN

Cross-sectional survey conducted May 2021-January 2022.

SETTING

Sixteen academic pediatric hospitals across the United States participating in the BrighT STAR Collaborative.

SUBJECTS

Pediatric critical care medicine physicians, advanced practice providers, respiratory therapists, and nurses.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

We summarized the proportion of positive responses for each question within a hospital and calculated the median proportion and IQR across hospitals. We correlated responses with culture rates and compared responses by role. Sixteen invited institutions participated (100%). Five hundred sixty-eight of 1,301 (44%) e-mailed individuals completed the survey (median hospital response rate 60%). Saline lavage was common, but no PICUs had a standardized approach. There was the highest variability in perceived likelihood (median, IQR) to obtain cultures for isolated fever (49%, 38-61%), isolated laboratory changes (49%, 38-57%), fever and laboratory changes without respiratory symptoms (68%, 54-79%), isolated change in secretion characteristics (67%, 54-78%), and isolated increased secretions (55%, 40-65%). Respiratory cultures were likely to be obtained as a "pan culture" (75%, 70-86%). There was a significant correlation between higher culture rates and likelihood to obtain cultures for isolated fever, persistent fever, isolated hypotension, fever, and laboratory changes without respiratory symptoms, and "pan cultures." Respondents across hospitals would find clinical decision support (CDS) helpful (79%) and thought that CDS would help align ICU and/or consulting teams (82%). Anticipated barriers to change included reluctance to change (70%), opinion of consultants (64%), and concern for missing a diagnosis of ventilator-associated infections (62%).

CONCLUSIONS

Respiratory culture collection and ordering practices were inconsistent, revealing opportunities for diagnostic stewardship. CDS would be generally well received; however, anticipated conceptual and psychologic barriers to change must be considered.

Guidelines for the Management of Respiratory Infectious Diseases in Children in Japan 2022

The members of the Japanese Society for Pediatric Infectious Diseases and the Japanese Society of Pediatric Pulmonology have developed Guidelines for the Management of Respiratory Infectious Diseases in Children with the objective of facilitating appropriate diagnosis, treatment and prevention of respiratory infections in children. The first edition was published in 2004 and the fifth edition was published in 2022. The Guideline 2022 consists of 2 parts, clinical questions and commentary, and includes general respiratory infections and specific infections in children with underlying diseases and severe infections. This executive summary outlines the clinical questions in the Guidelines 2022, with reference to the Japanese Medical Information Distribution Service Manual. All recommendations are supported by a systematic search for relevant evidence and are followed by the strength of the recommendation and the quality of the evidence statements.

Low Diagnostic Utility of Frequent Serial Tracheal Aspirate Cultures in the PICU

OBJECTIVES

To determine the diagnostic outcomes of serial tracheal aspirate cultures (TACs) in the PICU.

DESIGN

A retrospective chart review of TAC utilization was performed. Items recorded for each TAC included the time and date of culture acquisition, result, changes in microbial resistance patterns, antimicrobial therapy, and patient clinical course.

SETTING

A single urban tertiary care children's hospital in the United States.

SUBJECTS

Patients admitted to the PICU from January 1, to October 31, 2021, for whom a TAC was performed.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

One hundred fifty unique subjects had 582 TACs performed during the study period, of which 145 (24.9%) were serially repeated within 72 hours. Of these serial TACs, 82 (56.6%) had no growth, 41 (28.3%) grew the same organism as the prior culture, with most (36/41) displaying no major change in antimicrobial susceptibilities, 11 (7.6%) grew a new organism previously grown during the admission, and 11 (7.6%) grew a new organism not previously grown during the admission. Overall, only 26 of these serial TACs (17.9%) provided new diagnostic information, whereas only five (3.4%) led to a change in management.

CONCLUSIONS

Frequent serial TAC sampling in the PICU is common and infrequently yields new data that impact clinical decision-making. Considering worsening antimicrobial resistance and the role of diagnostic stewardship in mitigating it, these findings further support a 72-hour reassessment period before performing a repeat TAC in critically ill children.

Polymyxin flushes for endotracheal tube suction catheters in extremely low birth-weight infants: Any benefit in preventing ventilator-associated events?

We report that receipt of polymyxin B endotracheal tube suction catheter flushes did not reduce the incidence of pediatric ventilator-associated events (PedVAE) in infants weighing <1,000 g in this retrospective study. Incidence of PedVAE in our group of extremely low birth-weight infants was 6 per 1,000 ventilator days.

Colostrum and Preterm Babies: A Systematic Review

Colostrum from mothers is rich in immunomodulating bio-factors such as immunoglobulins (IgA), lactoferrin, and oligosaccharides and supports gut microbial and inflammatory processes. The support in these processes may provide some relief for infants who are born pre-term. Pre-term infants are more likely to develop necrotizing enterocolitis (NEC), late-onset sepsis (LOS), and ventilator-acquired/associated pneumonia (VAP). Due to the components of colostrum, there may be incentives towards early administration for preterm infants. An extensive literature review was done using ProQuest, ScienceDirect, and PubMed. Only meta-analyses and experimental studies were used. The search included the keywords 'colostrum and preterm' and 'colostrum and necrotizing enterocolitis'. The initial search generated 13,543 articles and was narrowed to 25 articles through comprehensive inclusion and exclusion criteria. There were significantly higher levels of Lactobacillus and Bifidobacterium in pre-term infants given colostrum and a decrease in Moraxellaceae and Staphylococcaceae. Salivary secretory IgA increased following oral colostrum administration in pre-term infants along with downregulation of interleukin (IL)-1b and IL-8. It was also observed that tumor necrosis factor (TNF)-a, and interferon-gamma (IFN-g) were significantly higher in the control group. There was no significant difference in the incidence of LOS, NEC, or VAP between pre-term infants receiving colostrum and those who did not. Secondary outcomes such as time to full enteral feeding were improved in pre-term infants receiving oral colostrum in addition to reduced hospital stays. Lastly, there was no difference in mortality between pre-term infants that received colostrum compared to those who did not.

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 (r_s = 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.

Epidemiology and outcomes of ventilator-associated events in critically ill children: Evaluation of three different definitions

OBJECTIVE

Ventilator-associated pneumonia (VAP) is one of the most common healthcare-associated infections in pediatric intensive care units (PICUs), but its definite diagnosis remains controversial. The CDC Ventilator-Associated Event (VAE) module (validated in adults) constitutes a new approach for VAP surveillance.

DESIGN

We described epidemiological characteristics of PICU VAE cases, investigated possible risk factors, and evaluated 3 different sets of diagnostic VAE criteria.

SETTING

This study was conducted in a PICU in a tertiary-care general hospital in northern Greece during 2017-2019.

PATIENTS

The study included patients aged 35 days-16 years who received mechanical ventilation.

METHODS

From medical records, we retrieved epidemiological data, clinical data, and laboratory characteristics as well as ventilator settings for our analysis. We assessed "oxygen deterioration" for the tier 1 CDC VAE module using 3 sets of diagnostic criteria: (1) CDC adult VAE criteria [increase of daily minimum fraction of inspired oxygen (FiO2) ≥ 0.2 or positive end expiratory pressure (PEEP) ≥ 3 cmH2O for 2 days], (2) the US pediatric VAE criteria [increase of FiO2 ≥ 0.25 or mean airway pressure (MAP) ≥ 4 cmH2O for 2 days], and (3) the European pediatric VAE criteria (increase of FiO2 ≥ 0.2 or PEEP ≥ 2 cmH2O for 1 day or increase of FiO2 ≥ 0.15 and PEEP ≥ 1 cm H2O for 1 day).

RESULTS

Among 326 children admitted to the PICU, 301 received mechanical ventilation. The incidence rate according to the CDC adult VAE criteria was 4.7 per 1,000 ventilator days. For the US pediatric VAE criteria the incidence rate was 6 per 1,000 ventilator days. For the European pediatric VAE criteria the incidence rate was 9.7 per 1,000 ventilator days. These results revealed statistically significant correlation of all 3 algorithms with adverse outcomes, including mortality.

CONCLUSIONS

All VAE algorithms were associated with higher mortality rates. Our findings highlight the need for a unified pediatric VAE definition to improve preventive strategies.

Impact of Organism Reporting from Endotracheal Aspirate Cultures on Antimicrobial Prescribing Practices in Mechanically Ventilated Pediatric Patients

Endotracheal aspirate cultures (EACs) help diagnose lower respiratory tract infections in mechanically ventilated patients but are limited by contamination with normal microbiota and variation in laboratory reporting. Increased use of EACs is associated with increased antimicrobial prescribing, but the impact of microbiology reporting on prescribing practices is unclear. This study was a retrospective analysis of EACs from mechanically ventilated patients at Children's Hospital Colorado (CHCO) admitted between 1 January 2019 and 31 December 2019. Chart review was performed to collect all culture and Gram stain components, as well as antibiotic use directed to organisms in culture. Reporting concordance was determined for each organism using American Society for Microbiology guidelines. Days of therapy were calculated for overreported and guideline-concordant organisms. A multivariable model was used to assess the relationship between organism reporting and total days of therapy. Overall, 448 patients with 827 EACs were included in this study. Among patients with tracheostomy, 25 (8%) organisms reported from EACs were overreported and contributed 48 days of excess therapy, while 227 (29%) organisms from the EACs of endotracheally intubated patients were overreported, contributing 472 excess days of therapy. After adjustment, organism overreporting was associated with a >2-fold-higher rate of antimicrobial therapy than guideline-concordant reporting (incident rate ratio [IRR], 2.83; 95% confidence interval [CI], 1.23, 6.53; P < 0.05). Overreported organisms from respiratory cultures contribute to excess antimicrobial therapy exposure in mechanically ventilated patients. Microbiology laboratories have an opportunity to mitigate antimicrobial overuse through standardized reporting practices.

Cost Analysis for Patients with Ventilator-Associated Pneumonia in the Neonatal Intensive Care Unit

The concept of improving the quality and safety of healthcare is well known. However, a follow-up question is often asked about whether these improvements are cost-effective. The prevalence of nosocomial infections (NIs) in the neonatal intensive care unit (NICU) is approximately 30% in developing countries. Ventilator-associated pneumonia (VAP) is the second most common NI in the NICU. Reducing the incidence of NIs can offer patients better and safer treatment and at the same time can provide cost savings for hospitals and payers. The aim of the study is to assess the direct costs of VAP in the NICU. This is a prospective study, conducted between January 2017 and June 2018 in the NICU of University Hospital “St. George” Plovdiv, Bulgaria. During this period, 107 neonates were ventilated for more than 48 h and included in the study. The costs for the hospital stay are based on the records from the Accounting Database of the setting. The differences directly attributable to VAP are presented both as an absolute value and percentage, based on the difference between the values of the analyzed variables. There are no statistically significant differences between patients with and without VAP in terms of age, sex, APGAR score, time of admission after birth and survival. We confirmed differences between the median birth weight (U = 924, p = 0.045) and average gestational age (t = 2.14, p = 0.035) of the patients in the two study groups. The median length of stay (patient-days) for patients with VAP is 32 days, compared to 18 days for non-VAP patients (U = 1752, p < 0.001). The attributive hospital stay due to VAP is 14 days. The median hospital costs for patients with VAP are estimated at €3675.77, compared to the lower expenses of €2327.78 for non-VAP patients (U = 1791.5, p < 0.001). The median cost for antibiotic therapy for patients with VAP is €432.79, compared to €351.61 for patients without VAP (U = 1556, p = 0.024). Our analysis confirms the results of other studies that the increased length of hospital stays due to VAP results in an increase in hospital costs. VAP is particularly associated with prematurity, low birth weight and prolonged mechanical ventilation.

Diagnostic Stewardship in the Pediatric Intensive Care Unit

In the pediatric intensive care unit (PICU), clinicians encounter complex decision making, balancing the need to treat infections promptly against the potential harms of antibiotics. Diagnostic stewardship is an approach to optimize microbiology diagnostic test practices to reduce unnecessary antibiotic treatment. We review the evidence for diagnostic stewardship of blood, endotracheal, and urine cultures in the PICU. Clinicians should consider 3 questions applying diagnostic stewardship: (1) Does the patient have signs or symptoms of an infectious process? (2) What is the optimal diagnostic test available to evaluate for this infection? (3) How should the diagnostic specimen be collected to optimize results?

Airway microbiome dynamics and relationship to ventilator-associated infection in intubated pediatric patients

BACKGROUND

Little is known about the airway microbiome in intubated mechanically ventilated children. We sought to characterize the airway microbiome longitudinally and in association with clinical variables and possible ventilator-associated infection (VAI).

METHODS

Serial tracheal aspirate samples were prospectively obtained from mechanically ventilated subjects under 3 years old from eight pediatric intensive care units in the United States from June 2017 to July 2018. Changes in the tracheal microbiome were analyzed by sequencing bacterial 16S ribosomal RNA gene relative to subject demographics, diagnoses, clinical parameters, outcomes, antibiotic treatment, and the Ventilator-Associated InfectioN (VAIN) score.

RESULTS

A total of 221 samples from 58 patients were processed and 197 samples met the >1000 reads criteria (89%), with an average of 43,000 reads per sample. The median number of samples per subject was 3 (interquartile range [IQR]: 2-5), with a median VAIN score of 2 (IQR: 1-3). Proteobacteria was the highest observed phyla throughout the intubation period, followed by Firmicutes and Actinobacteria. Alpha diversity was negatively associated with days of intubation (p = .032) and VAIN score (p = .016). High VAIN scores were associated with a decrease of Mycobacterium obuense, and an increase of Streptococcus peroris, Porphyromonadaceae family (unclassified species), Veillonella atypica, and several other taxa. No specific pattern of microbiome composition related to clinically diagnosed VAIs was observed.

CONCLUSIONS

Our data demonstrate decreasing alpha diversity with increasing VAIN score and days of intubation. No specific microbiome pattern was associated with clinically diagnosed VAI.

Association of Endotracheal Aspirate Culture Variability and Antibiotic Use in Mechanically Ventilated Pediatric Patients

IMPORTANCE

Endotracheal aspirate cultures are commonly collected from patients with mechanical ventilation to evaluate for ventilator-associated pneumonia or tracheitis. However, the respiratory tract is not sterile, making differentiating between colonization from bacterial infection challenging, and results may be unreliable owing to variable specimen quality and sample processing across laboratories. Despite these limitations, clinicians routinely interpret bacterial growth in endotracheal aspirate cultures as evidence of infection, sometimes regardless of organism significance, prompting antibiotic treatment.

OBJECTIVE

To assess the variability in endotracheal aspirate culture rates and the association between culture rates and antibiotic prescribing among patients with mechanical ventilation across children's hospitals in the US.

DESIGN, SETTING, AND PARTICIPANTS

Cross-sectional retrospective analysis of data obtained from the Children's Hospital Association Pediatric Health Information System database between January 1, 2016, through December 31, 2019. Participants were all patients hospitalized with mechanical ventilation aged less than 18 years.

EXPOSURES

A charge for an endotracheal aspirate culture on a ventilated day.

MAIN OUTCOMES AND MEASURES

Endotracheal aspirate culture rate and antibiotic days of therapy per ventilated days. For mechanical ventilation, clinical transaction classification codes for mechanical ventilation other unspecified ventilator assistance were used. To identify respiratory cultures, the laboratory test code for aerobic culture was used and relevant keywords (ie, respiratory tract, sputum) were used to identify sources in the hospital charge description master.

RESULTS

A total of 152 132 patients were identified among 31 hospitals. Among these patients, 79 691 endotracheal aspirate cultures were collected on a ventilator-day (patients aged less than 1 year, 44%; 1-4 years, 27%, 5-11 years. 16%, and 12-18 years, 13%; 3% were Asian; 17% Hispanic; 21% non-Hispanic Black; 45% Non-Hispanic White patients; 14% were other; 56% of patients were male, 44% were female). The overall median rate of culture use was 46 per 1000 ventilator-days (IQR, 32-73 cultures per 1000 ventilator-days). The endotracheal aspirate culture rate was positively correlated with the hospital's antibiotic days of therapy rate (R = 0.46; P = .009). In a multivariable model adjusting for patient-level and hospital-level characteristics and among patients with mechanical ventilation, each additional endotracheal aspirate culture was associated with 2.87 (95% CI, 2.74-3.01) higher odds of receiving additional days of therapy compared with patients who did not receive and endotracheal aspirate culture.

CONCLUSIONS AND RELEVANCE

In this study, notable variability was found in endotracheal aspirate culture rates across US pediatric hospitals and pediatric intensive care units, and endotracheal aspirate culture use was associated with increased antibiotic use. These findings suggest an opportunity for diagnostic and antibiotic stewardship to standardize testing and treatment of suspected ventilator-associated infections in pediatric patients with mechanical ventilation pediatric patients.

Oral mucosal mouthwash with chlorhexidine does not reduce the incidence of ventilator-associated pneumonia in critically ill children: A randomised controlled trial

BACKGROUND

Ventilator-associated pneumonia (VAP) is one of the most frequently encountered causes of hospital-acquired infection and results in high morbidity among intubated patients. Few trials have investigated the efficacy of oral care with chlorhexidine (CHX) mouthwash for the prevention of VAP in the paediatric population.

OBJECTIVES

The objective of this study was to assess the efficacy of CHX mouthwash in the prevention of VAP and to determine risk factors for VAP in children aged 1 month to 18 years admitted to the paediatric intensive care unit (PICU).

METHODS

This was a prospective, randomised, controlled, double-blind trial performed in the PICU. Patients were randomised into two groups receiving CHX (0.12%) (n = 88) or placebo (0.9% NaCl) (n = 86) and were followed up for VAP development. The main outcome measures were incidence of VAP, duration of hospital stay, duration of PICU stay, duration of ventilation, mortality, and the characteristics of organisms isolated in cases with VAP.

RESULTS

No difference was observed in the incidence of VAP and the type and distribution of organisms in the two groups (p > 0.05). In the CHX and placebo groups, we identified 21 and 22 patients with VAP, respectively. Incidence per 1000 ventilation days was 29.5 events in the CHX group and 35.1 events in the placebo group. Gram-negative bacteria were most common (71.4% in CHX vs. 54.5% in placebo). The use of 0.12% CHX did not influence hospital stay, PICU stay, ventilation, and mortality (p > 0.05). Multivariate analysis identified duration of ventilation as the only independent risk factor for VAP (p = 0.001).

CONCLUSION

The use of 0.12% CHX did not reduce VAP frequency among critically ill children. The only factor that increased VAP frequency was longer duration on ventilation. It appears that low concentration of CHX is not effective for VAP prevention, especially in the presence of multiresistant bacteria. CLINICALTRIALS.

GOV IDENTIFIER

NCT04527276.

Diagnostic Stewardship of Endotracheal Aspirate Cultures in a PICU

BACKGROUND

Clinicians commonly obtain endotracheal aspirate cultures (EACs) in the evaluation of suspected ventilator-associated infections. However, bacterial growth in EACs does not distinguish bacterial colonization from infection and may lead to overtreatment with antibiotics. We describe the development and impact of a clinical decision support algorithm to standardize the use of EACs from ventilated PICU patients.

METHODS

We monitored EAC use using a statistical process control chart. We compared the rate of EACs using Poisson regression and a quasi-experimental interrupted time series model and assessed clinical outcomes 1 year before and after introduction of the algorithm.

RESULTS

In the preintervention year, there were 557 EACs over 5092 ventilator days; after introduction of the algorithm, there were 234 EACs over 3654 ventilator days (an incident rate of 10.9 vs 6.5 per 100 ventilator days). There was a 41% decrease in the monthly rate of EACs (incidence rate ratio [IRR]: 0.59; 95% confidence interval [CI] 0.51-0.67; P < .001). The interrupted time series model revealed a preexisting 2% decline in the monthly culture rate (IRR: 0.98; 95% CI 0.97-1.0; P = .01), immediate 44% drop (IRR: 0.56; 95% CI 0.45-0.70; P = .02), and stable rate in the postintervention year (IRR: 1.03; 95% CI 0.99-1.07; P = .09). In-hospital mortality, hospital length of stay, 7-day readmissions, and All Patients Refined Diagnosis Related Group severity and mortality scores were stable. The estimated direct cost savings was $26 000 per year.

CONCLUSIONS

A clinical decision support algorithm standardizing EAC obtainment from ventilated PICU patients was associated with a sustained decline in the rate of EACs, without changes in mortality, readmissions, or length of stay.

Oropharyngeal colostrum therapy reduces the incidence of ventilator-associated pneumonia in very low birth weight infants: a systematic review and meta-analysis

BACKGROUND

Oropharyngeal colostrum (OC) is a novel feeding strategy to prevent complications of prematurity. A meta-analysis was conducted to investigate whether very low birth weight infants (VLBWs) can benefit from OC.

METHODS

Randomized controlled trials (RCTs) were searched from Embase, PubMed, Web of Science, and Cochrane Central Register of Controlled Trials from the date of inception until May 2019. RCTs were eligible if they used OC therapy on VLBW infants. The primary outcomes included ventilator-associated pneumonia (VAP), necrotizing enterocolitis (NEC), bronchopulmonary dysplasia (BPD), late-onset sepsis, and death. The secondary outcomes included the time of full enteral feeding and the length of stay.

RESULTS

Eight RCTs involving 682 patients (OC group: 332; non-OC group: 350) were included in the meta-analysis. The results suggested that OC was associated with a significantly reduced incidence of VAP [odds ratio (OR) = 0.39, 95% confidence interval (CI): 0.17-0.88, P = 0.02] and full enteral feeding days (mean difference = -2.66, 95% CI: -4.51 to -0.80, P = 0.005), a potential significance of NEC (OR = 0.51, 95% CI: 0.26-0.99, P = 0.05), a trend toward downregulating mortality (OR = 0.60, 95% CI: 0.34-1.08, P = 0.09) and proven sepsis (OR = 0.64, 95% CI: 0.40-1.01, P = 0.06).

CONCLUSIONS

OC could significantly reduce the occurrence of VAP, and consequently, its routine use should be considered for VLBWs to prevent infectious diseases.

IMPACT

OC significantly reduces the occurrence of VAP and NEC in VLBW infants. OC may reduce the incidence of VAP and NEC by increasing IgA levels. Early OC therapy for mechanical ventilation of low-weight infants may prevent the occurrence of VAP.

Challenging the "Culture" of the Tracheal Aspirate

The tracheal aspirate (TA) culture is commonly ordered in the NICU, but it has low sensitivity and specificity, limited by contamination. Interpretation of a TA culture out of context can lead to antibiotic overuse, which should be avoided. Clinicians should practice caution in the diagnosis of congenital pneumonia and use newer, published approaches to the diagnosis of ventilator-associated pneumonia in neonates. A subset of neonatal patients with risk factors of maternal fever or chorioamnionitis requiring intubation may benefit from TA culture performed within 12 hours after birth, to help identify an organism when blood culture may be negative, and tailor antimicrobial therapies. The more invasive, but more sensitive, technique of nonbronchoscopic bronchoalveolar lavage should be considered in older infants when bacterial isolation from the lower respiratory tract is necessary, because TA culture cannot distinguish between colonization and infection in that population.

Hospital-acquired Pneumonia and Ventilator-associated Pneumonia in Children: A Prospective Natural History and Case-Control Study

BACKGROUND

Clinical trials for antibiotics designed to treat hospital-acquired and ventilator-associated bacterial pneumonias (HABP/VABP) are hampered by making these diagnoses in a way that is acceptable to the United States Food and Drug Administration and consistent with standards of care. We examined laboratory and clinical features that might improve pediatric HABP/VABP trial efficiency by identifying risk factors predisposing children to HABP/VABP and describing the epidemiology of pediatric HABP/VABP.

METHODS

We prospectively reviewed the electronic medical records of patients <18 years of age admitted to intensive and intermediate care units (ICUs) if they received qualifying respiratory support or were started on antibiotics for a lower respiratory tract infection or undifferentiated sepsis. Subjects were followed until HABP/VABP was diagnosed or they were discharged from the ICU. Clinical, laboratory and imaging data were abstracted using structured chart review. We calculated HABP/VABP incidence and used a stepwise backward selection multivariable model to identify risk factors associated with development of HABP/VABP.

RESULTS

A total of 862 neonates, infants and children were evaluated for development of HABP/VABP; 10% (82/800) of those receiving respiratory support and 12% (103/862) overall developed HABP/VABP. Increasing age, shorter height/length, longer ICU length of stay, aspiration risk, blood product transfusion in the prior 7 days and frequent suctioning were associated with increased odds of HABP/VABP. The use of noninvasive ventilation and gastric acid suppression were both associated with decreased odds of HABP/VABP.

CONCLUSIONS

Food and Drug Administration-defined HABP/VABP occurred in 10%-12% of pediatric patients admitted to ICUs. Risk factors vary by age group.

Routine gastric residual volume measurement to guide enteral feeding in mechanically ventilated infants and children: the GASTRIC feasibility study

BACKGROUND

The routine measurement of gastric residual volume to guide the initiation and delivery of enteral feeding is widespread in paediatric intensive care and neonatal units, but has little underlying evidence to support it.

OBJECTIVE

To answer the question: is a trial of no gastric residual volume measurement feasible in UK paediatric intensive care units and neonatal units?

DESIGN

A mixed-methods study involving five linked work packages in two parallel arms: neonatal units and paediatric intensive care units. Work package 1: a survey of units to establish current UK practice. Work package 2: qualitative interviews with health-care professionals and caregivers of children admitted to either setting. Work package 3: a modified two-round e-Delphi survey to investigate health-care professionals' opinions on trial design issues and to obtain consensus on outcomes. Work package 4: examination of national databases to determine the potential eligible populations. Work package 5: two consensus meetings of health-care professionals and parents to review the data and agree consensus on outcomes that had not reached consensus in the e-Delphi study.

PARTICIPANTS AND SETTING

Parents of children with experience of ventilation and tube feeding in both neonatal units and paediatric intensive care units, and health-care professionals working in neonatal units and paediatric intensive care units.

RESULTS

Baseline surveys showed that the practice of gastric residual volume measurement was very common (96% in paediatric intensive care units and 65% in neonatal units). Ninety per cent of parents from both neonatal units and paediatric intensive care units supported a future trial, while highlighting concerns around possible delays in detecting complications. Health-care professionals also indicated that a trial was feasible, with 84% of staff willing to participate in a trial. Concerns expressed by junior nurses about the intervention arm of not measuring gastric residual volumes were addressed by developing a simple flow chart and education package. The trial design survey and e-Delphi study gained consensus on 12 paediatric intensive care unit and nine neonatal unit outcome measures, and identified acceptable inclusion and exclusion criteria. Given the differences in physiology, disease processes, environments, staffing and outcomes of interest, two different trials are required in the two settings. Database analyses subsequently showed that trials were feasible in both settings in terms of patient numbers. Of 16,222 children who met the inclusion criteria in paediatric intensive care units, 12,629 stayed for > 3 days. In neonatal units, 15,375 neonates < 32 weeks of age met the inclusion criteria. Finally, the two consensus meetings demonstrated 'buy-in' from the wider UK neonatal communities and paediatric intensive care units, and enabled us to discuss and vote on the outcomes that did not achieve consensus in the e-Delphi study.

CONCLUSIONS AND FUTURE WORK

Two separate UK trials (one in neonatal units and one in paediatric intensive care units) are feasible to conduct, but they cannot be combined as a result of differences in outcome measures and treatment protocols, reflecting the distinctness of the two specialties.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN42110505.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 23. See the NIHR Journals Library website for further project information.

The role of bacterial colonization of ventilator circuit in development of ventilator-associated pneumonia: a prospective observational cohort study

OBJECTIVES

Ventilator-associated pneumonia (VAP) is a significant cause of prolonged hospital stay and increased mortality in mechanically ventilated children. Studies of the relationship between bacterial colonization of ventilator circuits (VCs) and VAP are lacking. This study aimed to investigate the role of bacterial colonization of VCs in the development of VAP, and to provide evidence for preventing VAP.

METHODS

Mechanically ventilated patients admitted to the paediatric intensive care unit of a teaching hospital in China from October 2018 to November 2019 were enrolled. Specimens were collected from the VC and the patient's lower respiratory tract (LRT) for bacterial culture. Paired bacteria isolated from the VC and the patient's LRT, where colonization of the VC preceded that of the LRT, were evaluated for relatedness using pulsed field gel electrophoresis (PFGE).

RESULTS

A total of 114 patients were included; the incidence rate of VAP was 28.1% (32/114). A total of 1368 samples were collected from VCs; 16% had positive bacterial culture. There was no significant difference in bacterial colonization of VCs between VAP and non-VAP. In 13 patients, the LRT and VC were concurrently colonized with the same bacteria, where colonization of the VC occurred before colonization of the patient's LRT. PFGE results demonstrated high correlation between bacteria from the LRT and VC in 11 patients. Among 114 mechanically ventilated children, VAP caused by bacteria from the VC occurred in six patients, accounting for 18.8% (6/32) of the overall VAP rate in this study.

DISCUSSION

Bacterial colonization of the VC is a significant cause of VAP development in mechanically ventilated children. Preventive strategies for early identification and decontamination measures for contaminated VC may play a key role in preventing VAP.

Spontaneous Breathing Trial for Prediction of Extubation Success in Pediatric Patients Following Congenital Heart Surgery: A Randomized Controlled Trial

OBJECTIVES

To evaluate the usefulness of a spontaneous breathing trial for predicting extubation success in pediatric patients in the postoperative period after cardiac surgery compared with a physician-led weaning.

STUDY DESIGN

Randomized, controlled trial.

SETTING

PICU of a tertiary-care university hospital.

PATIENTS

A population of pediatric patients following cardiac surgery for congenital heart disease.

INTERVENTIONS

Patients on mechanical ventilation for more than 12 hours after surgery who were considered ready for weaning were randomized to the spontaneous breathing trial group or the control group. The spontaneous breathing trial was performed on continuous positive airway pressure with the pressure support of 10 cmH2O, the positive end-expiratory pressure of 5 cmH2O, and the fraction of inspired oxygen less than or equal to 0.5 for 2 hours. Patients in the control group underwent ventilator weaning according to clinical judgment.

MEASUREMENTS AND MAIN RESULTS

The primary endpoint was extubation success defined as no need for reintubation within 48 hours after extubation. Secondary outcomes were PICU length of stay, hospital length of stay, occurrence rate of ventilator-associated pneumonia, and mortality. One hundred and ten patients with the median age of 8 months were included in the study: 56 were assigned to the spontaneous breathing trial group and 54 were assigned to the control group. Demographic and clinical data and Risk Adjustment for Congenital Heart Surgery-1 classification were similar in both groups. Patients undergoing the spontaneous breathing trial had greater extubation success (83% vs 68%, p = 0.02) and shorter PICU length of stay (median 85 vs 367 hr, p < 0.0001) compared with the control group, respectively. There was no significant difference between groups in hospital length of stay, occurrence rate of ventilator-associated pneumonia, and mortality.

CONCLUSIONS

Pediatric patients with congenital heart disease undergoing the spontaneous breathing trial postoperatively had greater extubation success and shorter PICU length of stay compared with those weaned according to clinical judgment.

Acinetobacter baumannii Is a Risk Factor for Lower Respiratory Tract Infections in Children and Adolescents With a Tracheostomy

BACKGROUND

Lower respiratory tract infections (LRIs) are a major cause of hospitalization for children and adolescents with a tracheostomy. The aim of this study was to identify risk factors for LRI.

METHODS

In this retrospective study, we assessed the number of LRI and hospitalizations for LRI from 2004 to 2014 at the University Hospital Muenster Pediatric Department. We analyzed associations between LRI and clinical findings, and we cultured pathogens in tracheal aspirates (TAs) during noninfection periods. Univariable and multivariable negative, binomial regression analyses were applied to identify associations between possible risk factors and LRI.

RESULTS

Seventy-eight patients had 148 LRI, of which 99 were treated in hospital. The median number of LRI per year was 0.4. Six-hundred thirteen pathogens were detected in 315 specimens; Staphylococcus aureus (22.5%), Pseudomonas aeruginosa (14.8%) and Haemophilus influenzae (6.2%) were most frequently detected. Acinetobacter baumannii is an independent risk factor for LRI (rate ratio, 1.792; P = 0.030) and hospital admissions for LRI (rate ratio, 1.917; P = 0.011).

CONCLUSIONS

Children with a tracheostomy have frequent LRI. A. baumannii but not P. aeruginosa or S. aureus in TA is a risk factor for LRI in children with a long-term tracheostomy. This supports repetitive culture of TA for microbiologic workup to identify children and adolescents with an increased risk for LRI.

Decision-Making Around Positive Tracheal Aspirate Cultures: The Role of Neutrophil Semiquantification in Antibiotic Prescribing

OBJECTIVES

Ventilator-associated infections are a major contributor to antibiotic use in the PICU. Quantitative or semiquantitative assessment of neutrophils (microscopic purulence) is routinely reported in positive cultures from tracheal aspirates. The role of microscopic purulence in guiding antibiotic therapy or its association with symptoms of ventilator-associated infections is less described in children. We examine microscopic purulence as an independent predictor of antibiotic use for positive tracheal aspirate cultures in the PICU.

DESIGN

Retrospective cohort study.

SETTING

Tertiary care pediatric hospital.

PATIENTS

Children admitted to the PICU, neuro-PICU, or cardiac PICU with a positive tracheal aspirate culture from January 1, 2016, to December 31, 2016.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Positive tracheal aspirate cultures were reviewed. The outcome variable was antibiotic treatment that targeted the positive tracheal aspirate culture. The predictor variable was microscopic purulence, defined as moderate or many neutrophils on Gram stain report. Competing predictors included demographics, comorbidities, vital signs changes, respiratory support, and laboratory values. Of 361 positive cultures in the cohort, 81 (22%) were treated with antibiotics. Positive cultures with microscopic purulence were targeted for therapy more frequently (30% vs 11%). Microscopic purulence was the strongest predictor for antibiotic therapy (odds ratio, 3.3; 95% CI, 1.6-6.8) compared with fever (odds ratio, 2.0; 95% CI, 1.0-4.1) or increased respiratory support (odds ratio, 2.3; 95% CI, 1.2-4.3). There was no significant variation in symptomatology between microscopic purulence reported as moderate or many versus other (e.g., fever -24% vs 22%, increased respiratory support -36% vs 28%). Microscopic purulence was less prevalent with longer ventilator durations at the time of sampling.

CONCLUSIONS

Microscopic purulence was an independent predictor of antibiotic therapy for positive tracheal aspirate cultures in our PICUs. However, microscopic purulence was not associated with clinical symptomatology.

Soluble triggering receptor expressed on myeloid cells-1 as a useful biomarker for diagnosing ventilator-associated pneumonia after congenital cardiac surgery in children

The present study aimed to assess the usefulness of soluble triggering receptor expressed on myeloid cells 1 (sTREM-1) in the diagnosis of ventilator-associated pneumonia (VAP) in paediatric patients with congenital heart disease (CHD) following cardiac surgery. The current prospective study enrolled 48 patients with congenital heart diseases who were suspected of having VAP; these patients were undergoing cardiac surgery between August 2016 and October 2017 in the Cardiac Intensive Care Unit of Shanghai Children's Medical Center (Shanghai, China). A total of 31 patients were diagnosed with VAP using a polymerase chain reaction (PCR) assay, while 17 patients without VAP were designated as the Non-VAP group. A bronchoscopy was performed and samples were collected for measurement on the day that VAP was diagnosed. The sTREM-1 levels were measured in bronchoalveolar lavage fluid (BALF) and exhaled ventilator condensate (EVC). BALF specimens were also sent to the microbiology laboratory for PCR assays and quantitative culturing. The positive detection rate of bacteria using the PCR assay and traditional culture was 64.6% (31/48) and 39.6% (19/48). sTREM-1 was significantly higher in the BALF (146.21 pg/ml vs. 118.06 pg/ml) and EVC (125.29 pg/ml vs. 120.48 pg/ml) of patients with VAP demonstrated compared with the patients without VAP. The findings suggest that the detection of sTREM-1 in BALF and EVC samples may be useful for the diagnosis of VAP following heart surgery in children.

New Biomarkers to Diagnose Ventilator Associated Pneumonia: Pentraxin 3 and Surfactant Protein D

OBJECTIVE

To detect the most effective biomarker to confirm ventilator associated pneumonia (VAP).

METHODS

Fifty patients with VAP suspicious diagnosis and 30 healthy patients were recruited. Suspicion of VAP was established if patients met the modified CPIS score ≥ 6 points. The confirmation of VAP was defined by the quantitative culture of nonbronchoscopic bronchoalveolar lavage (BAL) >105 CFU/ml of pathogenic microorganism. Serum samples for determination of C-reactive protein (CRP), procalcitonin (PCT), pentraxin 3 (PTX3), surfactant protein D (SPD) were collected on suspected VAP.

RESULTS

Twenty seven of 50 patients were accepted as confirmed VAP group whose nonbronchoscopic BAL cultures were positive and rest of them were accepted as unconfirmed VAP group. PTX3, PCT and SPD levels were significantly higher in confirmed VAP group, (P = 0.021, P = 0.007, P < 0.001 respectively). There were no significant differences in CRP levels between the two groups (P = 0.062). The most sensitive marker for diagnosing VAP was SPD (P < 0.001). Receiver operating characteristic (ROC) curve for modified clinical pulmonary infection score (CPIS) to confirm VAP was evaluated (AUC 0.741 ± 0.07, P < 0.001) and the optimal cutoff value was >7 with a sensitivity of 51.85% and a specificity of 91.3%. SPD levels were significantly higher in Acinetobacter baumannii and Pseudomonas aeruginosa infected patients than culture negative patients (P < 0.001).

CONCLUSIONS

The index findings suggest that serum SPD is the most sensitive biomarker in diagnosis of VAP and it can be used as an early and organism specific marker for Acinetobacter baumannii and Pseudomonas aeruginosa.

Ventilator-Associated Pneumonia in Critically Ill Children: A New Paradigm

Ventilator-associated pneumonia (VAP) is a serious complication of critical illness. Surveillance definitions have undergone revisions for more objective and consistent reporting. The 1 organism-1 disease paradigm for microbial involvement may not adequately apply to many cases of VAP, in which pathogens are introduced to a pre-existing and often complex microbial community that facilitates or hinders the potential pathogen, consequently determining whether progression to VAP occurs. As omics technology is applied to VAP, a paradigm is emerging incorporating simultaneous assessments of microbial populations and their activity, as well as the host response, to personalize prevention and treatment.

Diagnostic value of bronchoalveolar lavage in children with nonresponding community-acquired pneumonia

BACKGROUND

Community-acquired pneumonia (CAP) is a common cause of morbidity and mortality in hospitalized children. In CAP, causative agents are seldom identified using noninvasive diagnostic procedures. For those children not responding to empiric antibiotic therapy, it is vital to identify the causative pathogens for further management.

METHODS

We aimed to determine the usefulness of identifying the causative agents by bronchoalveolar lavage (BAL) in hospitalized children with nonresponding CAP. Ninety children hospitalized for CAP and treated with empiric antibiotics but having persistent fever ≥48 hours were enrolled, and their BAL data were retrospectively reviewed.

RESULTS

Aerobic bacteria were isolated from 38 (42%) of 90 cultures, and anaerobic bacteria were isolated from eight (24%) of 33 cultures. The bacteria isolated most frequently were Streptococcus viridians (26.3%), Pseudomonas aeruginosa (23.7%), and Staphylococcus aureus (15.8%). Streptococcus pneumoniae was isolated from the BALs of only two children, and Haemophilus influenzae from none. For positive aerobic culture results, BAL results guided modifications of antibiotic regimens in 21 episodes (21 of 38, 55.3%).

CONCLUSION

BAL results guided a change of antimicrobials in 55% of children with positive aerobic cultures (29% of all children in the study) and contributed to a high rate of successful therapy.

Pilot study of dornase alfa (Pulmozyme) therapy for acquired ventilator-associated infection in preterm infants

OBJECTIVE

Evaluate the feasibility, safety, and efficacy of adjunctive treatment with dornase alfa in preterm patients with ventilator-associated pulmonary infection (VAPI) compared to standard care.

WORKING HYPOTHESIS

We hypothesize that therapy with dornase alfa will be safe and well tolerated in the preterm population with no worsening of symptoms, oxygen requirement, or need for respiratory support.

STUDY DESIGN

Prospective, randomized, blinded, pilot study comparing adjunctive treatment with dornase alfa to sham therapy. In addition to standard care, infants were randomized to receive dornase alfa 2.5 mg nebulized via endotracheal tube (ETT) every 12 hr for 7 days or sham therapy. ETT secretion gram stain and culture and chest X-ray (CXR) findings were evaluated. Respiratory support data were downloaded from the ventilator.

RESULTS

Fourteen infants developed VAPI between 2012 and 2014; 11 enrolled in the study. Six received dornase alfa and five received sham therapy. Average gestational age at birth was 25 weeks and age at study entry was 31 days. There were no differences in demographics, ETT white blood cell count (WBC), CXR, or mean airway pressure (MAP) between the two groups. There was a trend towards decreased oxygen requirement (FiO2) in the treatment group that did not reach statistical significance. No side effects were observed in the treatment group.

CONCLUSION

Treatment with dornase alfa is safe and treated infants had some improvement in FiO₂ requirement but no improvement in MAP. A larger randomized trial is needed to evaluate the efficacy of this therapy. Pediatr Pulmonol. 2017; 52:787-791. © 2017 Wiley Periodicals, Inc.

Ventilator-Associated Pneumonia in Low Birth Weight Neonates at a Neonatal Intensive Care Unit: A Retrospective Observational Study

BACKGROUND

Ventilator-associated pneumonia (VAP) is one of the most common healthcare-associated infections among ventilated patients. The aim of this study was to determine the clinical characteristics and risk factors for the development of VAP in intubated low birth weight (LBW) neonates in a neonatal intensive care unit.

METHODS

LBW infants (<2.5 kg) admitted to the neonatal intensive care unit of Kaohsiung Medical University Hospital from January 2005 to December 2009 were enrolled. We retrospectively analyzed perinatal and neonatal data of the enrolled intubated LBW infants by chart review.

RESULTS

Six hundred and five LBW infants were analyzed. One hundred and fourteen of the infants were intubated for >48 hours, 15 (13.2%) of whom had VAP. Of these 15 patients, the average age at onset of VAP was 24.0 ± 11.2 days, the average postmenstrual age was 30.6 ± 1.8 weeks, and the mean gestational age was 27.1 ± 2.3 weeks, which was significantly lower than the mean gestational age in the group without VAP (30.2 ± 3.5 weeks). The mean birth body weight was 944.4 ± 268.4 g in the VAP group and 1340.1 ± 455.4 g in the group without VAP (p < 0.001). Longer duration of intubation (odds ratio: 1.35, 95% confidence interval: 1.12-1.62) and parenteral nutrition (odds ratio: 1.32, 95% confidence interval: 1.14-1.51) were found in the VAP group after adjusting for gestational age and birth weight.

CONCLUSION

VAP was a problem for the LBW infants with intubation for >48 hours in our neonatal intensive care unit. VAP most frequently occurred at a postmenstrual age of 30-32 weeks in this study. Longer duration of tube placement and parenteral nutrition were found in the VAP group. Early removal of the endotracheal tube and adequate enteral nutrition may decrease the occurrence of VAP in LBW infants.

Pediatric Ventilator-Associated Infections: The Ventilator-Associated INfection Study

OBJECTIVE

Suspected ventilator-associated infection is the most common reason for antibiotics in the PICU. We sought to characterize the clinical variables associated with continuing antibiotics after initial evaluation for suspected ventilator-associated infection and to determine whether clinical variables or antibiotic treatment influenced outcomes.

DESIGN

Prospective, observational cohort study conducted in 47 PICUs in the United States, Canada, and Australia. Two hundred twenty-nine pediatric patients ventilated more than 48 hours undergoing respiratory secretion cultures were enrolled as "suspected ventilator-associated infection" in a prospective cohort study, those receiving antibiotics of less than or equal to 3 days were categorized as "evaluation only," and greater than 3 days as "treated." Demographics, diagnoses, comorbidities, culture results, and clinical data were compared between evaluation only and treated subjects and between subjects with positive versus negative cultures.

SETTING

PICUs in 47 hospitals in the United States, Canada, and Australia.

SUBJECTS

All patients undergoing respiratory secretion cultures during the 6 study periods.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Treated subjects differed from evaluation-only subjects only in frequency of positive cultures (79% vs 36%; p < 0.0001). Subjects with positive cultures were more likely to have chronic lung disease, tracheostomy, and shorter PICU stay, but there were no differences in ventilator days or mortality. Outcomes were similar in subjects with positive or negative cultures irrespective of antibiotic treatment. Immunocompromise and higher Pediatric Logistic Organ Dysfunction scores were the only variables associated with mortality in the overall population, but treated subjects with endotracheal tubes had significantly lower mortality.

CONCLUSIONS

Positive respiratory cultures were the primary determinant of continued antibiotic treatment in children with suspected ventilator-associated infection. Positive cultures were not associated with worse outcomes irrespective of antibiotic treatment although the lower mortality in treated subjects with endotracheal tubes is notable. The necessity of continuing antibiotics for a positive respiratory culture in suspected ventilator-associated infection requires further study.

Decreased Pseudomonas aeruginosa biofilm formation on nanomodified endotracheal tubes: a dynamic lung model

Ventilator-associated pneumonia (VAP) is a serious complication of mechanical ventilation that has been shown to be associated with increased mortality rates and medical costs in the pediatric intensive care unit. Currently, there is no cost-effective solution to the problems posed by VAP. Endotracheal tubes (ETTs) that are resistant to bacterial colonization and that inhibit biofilm formation could provide a novel solution to the problems posed by VAP. The objective of this in vitro study was to evaluate differences in the growth of Pseudomonas aeruginosa on unmodified polyvinyl chloride (PVC) ETTs and on ETTs etched with a fungal lipase, Rhizopus arrhizus, to create nanoscale surface features. These differences were evaluated using an in vitro model of the pediatric airway to simulate a ventilated patient in the pediatric intensive care unit. Each experiment was run for 24 hours and was supported by computational models of the ETT. Dynamic conditions within the ETT had an impact on the location of bacterial growth within the tube. These conditions also quantitatively affected bacterial growth especially within the areas of tube curvature. Most importantly, experiments in the in vitro model revealed a 2.7 log reduction in the number (colony forming units/mL) of P. aeruginosa on the nanoroughened ETTs compared to the untreated PVC ETTs after 24 hours. This reduction in total colony forming units/mL along the x-axis of the tube was similar to previous studies completed for Staphylococcus aureus. Thus, this dynamic study showed that lipase etching can create surface features of nanoscale roughness on PVC ETTs that decrease bacterial attachment of P. aeruginosa without the use of antibiotics and may provide clinicians with an effective and inexpensive tool to combat VAP.

Avoidance of Hospital-Acquired Infections in Pediatric Cardiac Surgical Patients

OBJECTIVES

The objectives of this review are to discuss the prevalence and risk factors associated with the development of hospital-acquired infections in pediatric patients undergoing cardiac surgery and the published antimicrobial prophylaxis regimens and rational approaches to the diagnosis, prevention, and treatment of nosocomial infections in these patients.

DATA SOURCE

MEDLINE and PubMed.

CONCLUSION

Hospital-acquired infections remain a significant source of potentially preventable morbidity and mortality in pediatric cardiac surgical patients. Through improved understanding of these conditions and implementation of avoidance strategies, centers caring for these patients may improve outcomes in this vulnerable population.

Evaluation of the New Centers for Disease Control and Prevention Ventilator-Associated Event Module and Criteria in Critically Ill Children in Greece

OBJECTIVE To evaluate the new adult Centers for Disease Control and Prevention (CDC) ventilator-associated event (VAE) module in critically ill children and compare with the traditionally used CDC definition for ventilator-associated pneumonia (VAP). DESIGN Retrospective observational study of mechanically ventilated children in a pediatric intensive care unit in Greece January 1-December 31, 2011. METHODS Assessment of new adult CDC VAE module including 3 definition tiers: ventilator-associated condition (VAC), infection-related VAC, and possible/probable ventilator-associated pneumonia (VAE-VAP); comparison with traditional CDC criteria for clinically defined pneumonia in mechanically ventilated children (PNEU-VAP). We recorded Pediatric Risk of Mortality score at admission (PRISM III), number of ventilator-days, and outcome. RESULTS Among 119 patients with mechanical ventilation (median [range] number of ventilator-days, 7 [1-183]), 19 patients experienced VAC. Criteria for VAE-VAP were fulfilled in 12 of 19 patients with VAC (63%). Children with either VAC or VAE-VAP were on ventilation more days than patients without these conditions (16.5 vs 5 d, P=.0006 and 18 vs 5 d, P<.001, respectively), whereas PRISM-III score was similar between them. Mortality was significant higher in patients with new VAE-VAP definition (50%), but not in patients with VAC (31.6%), than the patients without new VAE-VAP (14%, P=.007) or VAC (15%, P=.1), respectively. No significant association was found between PNEU-VAP and death. Incidences of PNEU-VAP and VAE-VAP were similar, but the agreement was poor. CONCLUSIONS VAE-VAP and PNEU-VAP found similar prevalence in critically ill children but with poor agreement. However, excess of death was significantly associated only with VAE-VAP. Infect Control Hosp Epidemiol 2016:1-5.

Implementation of a Ventilator-Associated Pneumonia Prevention Bundle in a Single PICU

OBJECTIVE

Ventilator-associated pneumonia is considered the second most frequent infection in pediatric intensive care, and there is agreement on its association with higher morbidity and increased healthcare costs. The goal of this study was to apply a bundle for ventilator-associated pneumonia prevention as a process for quality improvement in the PICU of Hospital Italiano de Buenos Aires, Argentina, aiming to decrease baseline ventilator-associated pneumonia rate by 25% every 6 months over a period of 2 years.

DESIGN

Quasi-experimental uninterrupted time series.

SETTING

PICU of Hospital Italiano de Buenos Aires, Argentina.

PATIENTS

All mechanical ventilated patients admitted to the unit.

INTERVENTION

It consisted of the implementation of an evidence-based ventilator-associated pneumonia prevention bundle adapted to our unit and using the plan-do-study-act cycle as a strategy for quality improvement. The bundle consisted of four main components: head of the bed raised more than 30°, oral hygiene with chlorhexidine, a clean and dry ventilator circuit, and daily interruption of sedation.

MEASUREMENTS AND MAIN RESULTS

Ventilator-associated pneumonia prevention team meetings started in March 2012, and the ventilator-associated pneumonia bundle was implemented in November 2012 after it had been developed and made operational. Baseline ventilator-associated pneumonia rate for the 2 years before intervention was 6.3 episodes every 1,000 mechanical ventilation days. ventilator-associated pneumonia rate evolution by semester and during the 2 years was, respectively, 5.7, 3.2, 1.8, and 0.0 episodes every 1,000 mechanical ventilation days. Monthly ventilator-associated pneumonia rate time series summarized in a 51-point control chart showed the presence of special cause variability after intervention was implemented.

CONCLUSIONS

The implementation over 2 years of a ventilator-associated pneumonia prevention bundle specifically adapted to our unit using quality improvement tools was associated with a reduction in ventilator-associated pneumonia rate of 25% every 6 months and a nil rate in the last semester.

Diagnosis and Treatment of Ventilator-Associated Infection: Review of the Critical Illness Stress-Induced Immune Suppression Prevention Trial Data

OBJECTIVES

The Critical Illness Stress-Induced Immune Suppression prevention trial was a randomized, masked trial of zinc, selenium, glutamine, and metoclopramide compared with whey protein in delaying nosocomial infection in PICU patients. One fourth of study subjects were diagnosed with nosocomial lower respiratory infection, which contributed to subjects receiving antibiotics 74% of all patient days in the PICU. We analyzed diagnostic and treatment variability among the participating institutions and compared outcomes between nosocomial lower respiratory infection subjects (n = 74) and intubated subjects without nosocomial infection (n = 1 55).

DESIGN

Post hoc analysis.

SETTING

Eight hospitals in the Collaborative Pediatric Critical Care Research Network.

PATIENTS

Critical Illness Stress-Induced Immune Suppression study subjects.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Variability across institutions existed in the frequency and manner by which respiratory secretion cultures were obtained, processed, and results reported. Most results were reported semiquantitatively, and both Gram stains and antibiotic sensitivities were frequently omitted. The nosocomial lower respiratory infection diagnosis was associated with increased PICU lengths of stay compared with those who were intubated without nosocomial infection (24 ± 19 vs 9 ± 6 d; p < 0.001) and antibiotic use (38 ± 29 vs 15 ± 20 antibiotics days; p < 0.001). Despite antibiotic treatment, the same bacteria persisted in 45% of follow-up cultures.

CONCLUSIONS

The Critical Illness Stress-Induced Immune Suppression data demonstrate that the nosocomial lower respiratory infection diagnosis is associated with longer lengths of stay and increased antibiotic use, but there is considerable diagnostic and treatment variability across institutions. More rigorous standards for when and how respiratory cultures are obtained, processed, and reported are necessary. Bacterial persistence also complicates the interpretation of follow-up cultures.

An Evaluation of Various Ventilator-Associated Infection Criteria in a PICU

OBJECTIVE

To describe characteristics and overlap associated with various ventilator-associated infection criteria in the PICU.

DESIGN

Retrospective observational study.

SETTING

A quaternary care children's hospital PICU.

PATIENTS

Children ventilated more than 48 hours, excluding patients with tracheostomy.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Ventilator-associated infection, including pneumonia, infection-related ventilator-associated condition, tracheobronchitis, and lower respiratory tract infection were defined according to criteria from the Centers for Disease Control and Prevention or medical literature. Clinical data were abstracted to assign diagnoses of each ventilator-associated infection. In 300 episodes of mechanical ventilation, there were 30 individual episodes of ventilator-associated infection. Nine episodes met more than one definition. Rates per 1,000 ventilator days were 2.60 for ventilator-associated pneumonia, 2.16 for infection-related ventilator-associated condition, 5.19 for ventilator-associated tracheobronchitis, and 6.92 for lower respiratory tract infection. The rate of any ventilator-associated infection was 12.98 per 1,000 ventilator days. Individual criteria had similar risk factors and outcomes. Risk factors for development of any ventilator-associated infection included older age (p = 0.003) and trauma (p = 0.007), while less cardiac surgery patients developed ventilator-associated infection (p = 0.015). On multivariate analysis, trauma was the only independent risk factor (adjusted odds ratio, 3.10; 95% CI, 1.15-8.38). Developing any ventilator-associated infection was associated with longer duration of mechanical ventilation (p < 0.001) and longer PICU length of stay (p < 0.001) but not PICU mortality (p = 0.523).

CONCLUSIONS

There is little overlap in diagnosis of various ventilator-associated infection. However, the risk factors and outcomes associated with individual criteria are similar, indicating that they may have validity in identifying true pathology. Ventilator-associated infection in general is likely a larger problem than indicated by low hospital-reported rates of ventilator-associated pneumonia. There is clinical confusion due to the presence of several diagnostic criteria for ventilator-associated infection. Developing a more inclusive and clinically relevant criterion for diagnosing ventilator-associated infection is warranted to accurately assess their impact and improve guidance for clinicians in evaluating and treating ventilator-associated infection.

A Case-Control Study on the Impact of Ventilator-Associated Tracheobronchitis in the PICU

OBJECTIVES

Hospital-acquired infections increase morbidity, mortality, and charges in the PICU. We implemented a quality improvement bundle directed at ventilator-associated pneumonia in our PICU in 2005. We observed an increase in ventilator-associated tracheobronchitis coincident with the near-elimination of ventilator-associated pneumonia. The impact of ventilator-associated tracheobronchitis on critically ill children has not been previously described. Accordingly, we hypothesized that ventilator-associated tracheobronchitisis associated with increased length of stay, mortality, and hospital charge.

DESIGN

Retrospective case-control study.

PATIENTS

Critically ill children admitted to a quaternary PICU at a free-standing academic children's hospital in the United States.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

We conducted a retrospective case control study, with institutional review board approval, of 77 consecutive cases of ventilator-associated tracheobronchitis admitted to our PICU from 2004-2010. We matched each case with a control based on the following criteria (in rank order): age range (< 30 d, 30 d to 24 mo, 24 mo to 12 yr, > 12 yr), admission Pediatric Risk of Mortality III score ± 10, number of ventilator days of control group (> 75% of days until development of ventilator-associated tracheobronchitis), primary diagnosis, underlying organ system dysfunction, surgical procedure, and gender. The primary outcome measured was PICU length of stay. Secondary outcomes included ventilator days, hospital length of stay, mortality, and PICU and hospital charges. Data was analyzed using chi square analysis and p less than 0.05 was considered significant. We successfully matched 45 of 77 ventilator-associated tracheobronchitis patients with controls. There were no significant differences in age, gender, diagnosis, or Pediatric Risk of Mortality III score between groups. Ventilator-associated tracheobronchitis patients had a longer PICU length of stay (median, 21.5 d, interquartile range, 24 d) compared to controls (median, 18 d; interquartile range, 17 d), although not statistically significant (p = 0.13). Ventilator days were also longer in the ventilator-associated tracheobronchitis patients (median, 17 d; IQR, 22 d) versus control (median, 10.5 d; interquartile range, 13 d) (p = 0.01). There was no significant difference in total hospital length of stay (54 d vs 36 d; p = 0.69). PICU mortality was higher in the ventilator-associated tracheobronchitis group (15% vs 5%; p = 0.14), although not statistically significant. There was an increase in both median PICU charges ($197,393 vs $172,344; p < 0.05) and hospital charges ($421,576 vs $350,649; p < 0.05) for ventilator-associated tracheobronchitis patients compared with controls.

CONCLUSIONS

Ventilator-associated tracheobronchitis is a clinically significant hospital-acquired infection in the PICU and is associated with longer duration of mechanical ventilation and healthcare costs, possibly through causing a longer PICU length of stay. Quality improvement efforts should be directed at reducing the incidence of ventilator-associated tracheobronchitis in the PICU.

Diagnosing ventilator-associated pneumonia in pediatric intensive care

The Centers for Disease Control and Prevention's criteria were applied by independent investigators for ventilator-associated pneumonia (VAP) diagnosis in critically ill children and compared with tracheal aspirate cultures (TACs). In addition, correlation between antibiotic use, VAP incidence, and epidemiology of TACs was investigated. A modest agreement (κ = 0.41) was found on radiologic findings between 2 investigators. VAP incidence was 7.7 episodes per 1,000 ventilator days, but positive TACs were the most significant factor for driving high antimicrobial usage in the pediatric intensive care unit.