Brian D. Benneyworth

Existing data analysis in pediatric critical care research

Our objectives were to review and categorize the existing data sources that are important to pediatric critical care medicine (PCCM) investigators and the types of questions that have been or could be studied with each data source. We conducted a narrative review of the medical literature, categorized the data sources available to PCCM investigators, and created an online data source registry. We found that many data sources are available for research in PCCM. To date, PCCM investigators have most often relied on pediatric critical care registries and treatment- or disease-specific registries. The available data sources vary widely in the level of clinical detail and the types of questions they can reliably answer. Linkage of data sources can expand the types of questions that a data source can be used to study. Careful matching of the scientific question to the best available data source or linked data sources is necessary. In addition, rigorous application of the best available analysis techniques and reporting consistent with observational research standards will maximize the quality of research using existing data in PCCM.

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.

Variation in extubation failure rates after neonatal congenital heart surgery across Pediatric Cardiac Critical Care Consortium hospitals

Objective: In a multicenter cohort of neonates recovering from cardiac surgery, we sought to describe the epidemiology of extubation failure and its variability across centers, identify risk factors, and determine its impact on outcomes. Methods: We analyzed prospectively collected clinical registry data on all neonates undergoing cardiac surgery in the Pediatric Cardiac Critical Care Consortium database from October 2013 to July 2015. Extubation failure was defined as reintubation less than 72 hours after the first planned extubation. Risk factors were identified using multivariable logistic regression with generalized estimating equations to account for within‐center correlation. Results: The cohort included 899 neonates from 14 Pediatric Cardiac Critical Care Consortium centers; 14% were premature, 20% had genetic abnormalities, 18% had major extracardiac anomalies, and 74% underwent surgery with cardiopulmonary bypass. Extubation failure occurred in 103 neonates (11%), within 24 hours in 61%. Unadjusted rates of extubation failure ranged from 5% to 22% across centers; this variability was unchanged after adjusting for procedural complexity and airway anomaly. After multivariable analysis, only airway anomaly was identified as an independent risk factor for extubation failure (odds ratio, 3.1; 95% confidence interval, 1.4–6.7; P = .01). Neonates who failed extubation had a greater median postoperative length of stay (33 vs 23 days, P < .001) and in‐hospital mortality (8% vs 2%, P = .002). Conclusions: This multicenter study showed that 11% of neonates recovering from cardiac surgery fail initial postoperative extubation. Only congenital airway anomaly was independently associated with extubation failure. We observed a 4‐fold variation in extubation failure rates across hospitals, suggesting a role for collaborative quality improvement to optimize outcomes.

Pediatric Cardiac Tumors A 45-year, Single-Institution Review

Background: Cardiac tumors in children are rare. Of the cases reported in the literature, nearly all are benign and managed conservatively. Methods: This is a retrospective, observational study of pediatric patients <18 years who presented for surgical evaluation of a cardiac tumor, between 1969 and 2014 at a tertiary care children’s hospital. Presentation, pathology, management, and outcomes were evaluated. Results: Over the last 45 years, 64 patients were evaluated for surgical resection of a cardiac tumor. Rhabdomyoma was the most common neoplasm (58%), and 17% of the tumors had malignant pathologies. While 42% of benign cardiac neoplasms required surgical intervention for significant hemodynamic concerns, 73% of malignant neoplasms underwent radical excision, if possible, followed by adjuvant chemotherapy. Despite a 37% mortality in patients with malignant pathology, an aggressive surgical approach can yield long-term survival in some patients. There were no deaths among patients with benign tumors and 17% had postoperative complications mostly related to mitral regurgitation. Conclusion: Cardiac tumors in children are rare but can be managed aggressively with good outcomes. Benign tumors have an excellent survival with most complications related to tumor location. Malignant tumors have a high mortality rate, but surgery and adjuvant chemotherapy allow for prolonged survival in selected patients.

Variation in Surgical Antibiotic Prophylaxis for Outpatient Pediatric Urological Procedures at United States Children’s Hospitals

Purpose: Guidelines recommend surgical antibiotic prophylaxis for clean‐contaminated procedures but none for clean procedures. The purpose of this study was to describe variations in surgical antibiotic prophylaxis for outpatient urological procedures at United States children’s hospitals. Materials and Methods: Using the PHIS (Pediatric Health Information System®) database we performed a retrospective cohort study of patients younger than 18 years who underwent clean and/or clean‐contaminated outpatient urological procedures from 2012 to 2014. We excluded those with concurrent nonurological procedures or an abscess/infected wound. We compared perioperative antibiotic charges for clean vs clean‐contaminated procedures using a multilevel logistic regression model with a random effect for hospital. We also examined whether hospitals that were guideline compliant for clean procedures, defined as no surgical antibiotic prophylaxis, were also compliant for clean‐contaminated procedures using the Pearson correlation coefficient. We examined hospital level variation in antibiotic rates using the coefficient of variation. Results: A total of 131,256 patients with a median age of 34 months at 39 hospitals met study inclusion criteria. Patients undergoing clean procedures were 14% less likely to receive guideline compliant surgical antibiotic prophylaxis than patients undergoing clean‐contaminated procedures (OR 0.86, 95% CI 0.84–0.88, p <0.0001). Hospitals that used antibiotics appropriately for clean‐contaminated procedures were more likely to use antibiotics inappropriately for clean procedures (r = 0.7, p = 0.01). Greater variation was seen for hospital level compliance with surgical antibiotic prophylaxis for clean‐contaminated procedures (range 9.8% to 97.8%, coefficient of variation 0.36) than for clean procedures (range 35.0% to 98.2%, coefficient of variation 0.20). Conclusions: Hospitals that used surgical antibiotic prophylaxis appropriately for clean‐contaminated procedures were likely to use surgical antibiotic prophylaxis inappropriately for clean procedures. More variation was seen in hospital level guideline compliance for clean‐contaminated procedures.

The trauma registry compared to All Patient Refined Diagnosis Groups (APR-DRG)

BACKGROUND Literature has shown there are significant differences between administrative databases and clinical registry data. Our objective was to compare the identification of trauma patients using All Patient Refined Diagnosis Related Groups (APR-DRG) as compared to the Trauma Registry and estimate the effects of those discrepancies on utilization. METHODS Admitted pediatric patients from 1/2012-12/2013 were abstracted from the trauma registry. The patients were linked to corresponding administrative data using the Pediatric Health Information System database at a single childrens hospital. APR-DRGs referencing trauma were used to identify trauma patients. We compared variables related to utilization and diagnosis to determine the level of agreement between the two datasets. RESULTS There were 1942 trauma registry patients and 980 administrative records identified with trauma-specific APR-DRG during the study period. Forty-two percent (816/1942) of registry records had an associated trauma-specific APR-DRG; 69% of registry patients requiring ICU care had trauma APR-DRGs; 73% of registry patients with head injuries had trauma APR-DRGs. Only 21% of registry patients requiring surgical management had associated trauma APR-DRGs, and 12.5% of simple fractures had associated trauma APR-DRGs. CONCLUSION APR-DRGs appeared to only capture a fraction of the entire trauma population and it tends to be the more severely ill patients. As a result, the administrative data was not able to accurately answer hospital or operating room utilization as well as specific information on diagnosis categories regarding trauma patients. APR-DRG administrative data should not be used as the only data source for evaluating the needs of a trauma program.

Tracheostomy Following Surgery for Congenital Heart Disease A 14-year Institutional Experience

Background: Tracheostomy following congenital heart disease (CHD) surgery is a rare event and associated with significant mortality. Hospital survival has been reported from 20% to 40%. Late mortality for these patients is not well characterized. Methods: We performed a retrospective observational study of patients who had a tracheostomy following CHD surgery (excluding isolated patent ductus arteriosus ligation) between January 2000 and December 2013. Patients were categorized into single-ventricle or biventricular physiology groups. Demographics, genetic syndromes, pulmonary disease, and comorbidities were collected. Outcomes including hospital survival, long-term survival, and weaning from positive pressure ventilation are reported. Bivariate and time-to-event models were used. Results: Over a 14-year period, 61 children (0.9% incidence) had a tracheostomy placed following CHD surgery. There were 12 single-ventricle patients and 49 biventricular patients. Prematurity, genetic syndromes, lung/airway disease, and other comorbidities were common in both CHD groups. Gastrostomy tubes were used more frequently in biventricular physiology patients (91.8%) versus single-ventricle patients (66.7%, P = .04). Survival to hospital discharge was 50% in the single-ventricle group compared to 86% in biventricular patients (P = .01). Long-term survival continued to be poor in the single-ventricle group comparatively (three years, 27.8% vs 64.8%, P = .01). Gastrostomy tube placement was independently associated with survival in both groups (P = .002). Conclusion: Tracheostomy is performed following many types of surgery for CHD and is commonly associated with other comorbidities. Both hospital and long-term survival are substantially lower in children with single-ventricle physiology as compared to patients with biventricular physiology.

The Incidence of Ventilator-Associated Infections in Children Determined Using Bronchoalveolar Lavage.

Hospital-acquired infections are a major contributor to inpatient morbidity, mortality, and health care costs. Ventilator-associated pneumonia (VAP) is among the most common. It is associated with longer duration of mechanical ventilation (MV), longer intensive care unit stays, increase in cost per case of VAP of at least

Retrospective Evaluation of the Epidemiology and Practice Variation of Dexmedetomidine Use in Invasively Ventilated Pediatric Intensive Care Admissions, 2007–2013

40 000, and over 2-fold increased risk of mortality.1,2 Hospital rates of VAP are subject to mandated reporting and measured against national benchmarks. However, because the definition of VAP is complex and includes subjective signs and symptoms, the reported incidence in children varies widely from 0.3 to 45.1 cases per 1000 ventilator days.3 VAP may not include all clinically important infections associated with MV.4 Another infection, ventilator-associated tracheobronchitis (VAT), has been described using varying definitions with unclear clinical significance. The incidence of VAT in pediatric intensive care unit (PICU) populations has been reported at 3.4% to 7.3% of ventilated patients, and as high as 21.2% in trauma patients.5-9 VAT has been associated with longer duration of MV and length of stay but not increased mortality.5-7 Variable definitions have been used in studies of VAT, but generally include clinical signs of respiratory infection in the absence of pneumonia on chest radiograph combined with a positive respiratory culture.8,9 Recent studies of VAT in pediatrics have all used a definition based on the Centers for Disease Control and Prevention/National Healthcare Safety Network (CDC/NHSN) definition of “lower respiratory tract infection other than pneumonia” and applied it to children on MV.5-7,10 Definitions of VAT, and those of VAP, are complicated by their reliance on poor interpretability and subjectivity of data including clinical signs and chest radiographs. Microbiologic testing is complicated due to the lack of standard microbiologic methods.3 Respiratory specimens can be obtained by bronchoscopic or non-bronchoscopic bronchoalveolar lavage (BAL), by protected specimen brush, or by endotracheal aspirate (ETA) via new or inline suction catheters. ETA may be preferred due to perceived safety, feasibility, and cost concerns.4 However, validity of cultures obtained by ETA may be questioned due to bacterial colonization of endotracheal tubes. Quantitative bacterial cultures may improve specificity of ETA cultures for infection over colonization, and a threshold of >105 cfu/mL has been suggested.9 Publications on VAT have invariably used ETA as the method to obtain specimens, but have varied in the use of quantitative culture. In our institution, BAL is used for the routine evaluation of ventilator-associated infections including VAP and VAT. Surveillance cultures and ETA are not performed due to concerns of interpretability of results. Because of this, we are in a unique position to provide the first report of BAL results in a large cohort of PICU patients. We hypothesized that VAP represents only a small portion of positive BALs, suggesting that other potentially significant ventilator-associated infections are not well characterized.

Tracheostomy After Operations for Congenital Heart Disease: An Analysis of the Society of Thoracic Surgeons Congenital Heart Surgery Database.

Objectives The study assessed dexmedetomidine utilization and practice variation over time in ventilated pediatric intensive care unit (PICU) patients; and evaluated differences in hospital outcomes between high- and low-dexmedetomidine utilization hospitals. Study design This serial cross-sectional analysis used administrative data from PICU admissions in the pediatric health information system (37 US tertiary care pediatric hospitals). Included admissions from 2007 to 2013 had simultaneous dexmedetomidine and invasive mechanical ventilation charges, <18 years of age, excluding neonates. Patient and hospital characteristics were compared as well as hospital-level severity-adjusted indexed length of stay (LOS), charges, and mortality. Results The utilization of dexmedetomidine increased from 6.2 to 38.2 per 100 ventilated PICU patients among pediatric hospitals. Utilization ranged from 3.8 to 62.8 per 100 in 2013. Few differences in patient demographics and no differences in hospital-level volume/severity of illness measures between high- and low-utilization hospitals occurred. No differences in hospital-level, severity-adjusted indexed outcomes (LOS, charges, and mortality) were found. Conclusion Wide practice variation in utilization of dexmedetomidine for ventilated PICU patients existed even as use has increased sixfold. Higher utilization was not associated with increased hospital charges or reduced hospital LOS. Further work should define the expected outcome benefits of dexmedetomidine and its appropriate use.