Bradley A. Kuch

Pediatric Specialized Transport Teams Are Associated With Improved Outcomes

OBJECTIVE: The goal was to test the hypothesis that interfacility transport performed by a pediatric critical care specialized team, compared with nonspecialized teams, would be associated with improved survival rates and fewer unplanned events during the transport process. METHODS: A single-center, prospective, cohort study was performed between January 2001 and September 2002. A total of 1085 infants and children at referral community hospitals with requests for retrieval by the Childrens Hospital of Pittsburgh transport team were studied; 1021(94%) were transported by a specialty team and 64 (6%) by nonspecialized teams. Unplanned events during the transport process and 28-day mortality rates were assessed. RESULTS: Unplanned events occurred for 55 patients (5%) and were more common among patients transported by nonspecialized teams (61% vs 1.5%). Airway-related events were most common, followed by cardiopulmonary arrest, sustained hypotension, and loss of crucial intravenous access. After adjustment for illness severity, only the use of a nonspecialized team was independently associated with an unplanned event, and death was more common among patients transported by nonspecialized teams (23% vs 9%). CONCLUSION: Transport of critically ill children to a pediatric tertiary care center can be conducted more safely with a pediatric critical care specialized team than with teams lacking specific training and expertise in pediatric critical care and pediatric transport medicine.

Mortality and Functional Morbidity After Use of PALS/APLS by Community Physicians

OBJECTIVES: To test the hypothesis that pediatric shock is a common cause of death and functional morbidity and that pediatric advanced life support (PALS)/advanced pediatric life support (APLS) resuscitation in the community hospital setting improves child health outcomes. METHODS: This study included all children consecutively transported to 5 regional, tertiary care childrens hospitals over 4 years, and is a prospective cohort study comparing outcomes in children who did or did not receive PALS/APLS resuscitation in the community hospital. RESULTS: Shock occurred in 37% of the patients transferred to the tertiary centers. Regardless of trauma status, children with shock had an increased mortality rate compared with those without shock (all patients: 11.4% vs 2.6%), trauma patients (28.3% vs 1.2%), and nontrauma patients (10.5% vs 2.8%). Early shock reversal was associated with reduced mortality (5.06% vs 16.37%) and functional morbidity (1.56% vs 4.11%) rates. Early use of PALS/APLS-recommended interventions was associated with reduced mortality (8.69% vs 15.01%) and functional morbidity (1.24% vs 4.23%) rates. After controlling for center, severity of illness, and trauma status, early reversal of shock and use of PALS/APLS-recommended interventions remained associated with reduced morbidity and mortality rates. CONCLUSIONS: Shock is common in children who are transferred for tertiary care. Pediatric shock recognition and resuscitation in the community hospital improves survival and functional outcome regardless of diagnostic category. The development of shock/trauma systems for children with and without trauma seems prudent.

The association of renal dysfunction and the use of aprotinin in patients undergoing congenital cardiac surgery requiring cardiopulmonary bypass.

BACKGROUND: The use of large-dose aprotinin during cardiopulmonary bypass (CPB) in adult patients has been linked to postoperative renal dysfunction, but its effect on the pediatric population undergoing complex congenital cardiac operations is not well defined. METHODS: We used a retrospective cohort analysis to evaluate children undergoing cardiac surgery requiring CPB between July 2004 and July 2006. Demographic data and surgical risk quantified by the Aristotle surgical complexity level were analyzed as covariates. Renal dysfunction was defined according to the RIFLE criteria, an international consensus classification which defines three grades of increasing severity of acute kidney injury: risk (Class R), injury (Class I), and failure (Class F) based on serum creatinine values. A univariate and multivariate logistic regression analysis and a propensity score were used to analyze the data. The propensity score was developed using pretreatment covariates associated with the administration of aprotinin. A multivariate logistic regression was then used with the propensity score and intraoperative measures as covariates. A P value <0.05 was considered statistically significant. RESULTS: Among 395 patients who underwent cardiac surgery, 55% received aprotinin and 45% did not. Thirty-one percent of the cohort had previous cardiac surgery; 17% were neonates. According to the RIFLE criteria, 80 of the patients (20.3%) had acute kidney injury in the postoperative period; 53 (13.4%) had risk of renal dysfunction with 23 (5.8%) having injury and four patients (0.7%) having failure. Those receiving aprotinin had a higher incidence of previous cardiac surgery (54.1% vs 5%), sepsis (6.9% vs.0.0%), heart failure (24.8% vs 12.4%), mechanical ventilation (25.2% vs 2.8%), or mechanical circulatory support (6.0% vs.0.6%). More patients had an Aristotle level of 4 (26.6% vs 2.8%) and were treated with diuretics (63.8% vs 26.6%), angiotensin converting enzyme inhibitors (21.1% vs 7.9%), milrinone (25.7% vs 4.5%), and inotropic support (16.1% vs 2.3%). Although there was a significant difference in the unadjusted risk of renal dysfunction, adjustment with the preoperative propensity score revealed that there was no association between aprotinin and renal dysfunction (OR 1.32; 95% CI 0.55–3.19). The duration of CPB was the only independent variable associated with the development of renal dysfunction (OR 1.0; 95% CI 1.009–1.014). CONCLUSIONS: Patients who receive aprotinin are more likely to present with preoperative risk factors for the development of postoperative renal dysfunction. However, when associated risk factors are properly considered, the use of aprotinin does not seem to be associated with a higher risk of developing renal dysfunction in the immediate postoperative period in children.

Extubation after cardiothoracic surgery in neonates, children, and young adults: One year of institutional experience.

Objective: Describe risk factors associated with successful and early extubation in the pediatric cardiac intensive care unit. Design: Retrospective chart review. Setting: University hospital, cardiac intensive care unit. Measurements and Main Results: Review of 212 consecutive surgical admissions from January 2003 to January 2004, excluding deaths. Preoperative, intraoperative, and postoperative variables were studied. Successful extubation was defined as no reintubation at any time during the cardiac intensive care unit course and early extubation was defined as mechanical ventilation ≤24 hrs. Median subject age was 8 months (range, 1 day-25 yrs), with 57% <1 yr of age and 22% neonates. Fifty-eight (27%) were extubated in the operating room and 122 (58%) were extubated at <24 hrs (mean, 6.1 ± 7.7 hrs). Only seven patients failed extubation: three in the operating room because of upper airway obstruction and four in the cardiac intensive care unit for acute respiratory failure associated with atelectasis (n = 2), ventricular dysfunction (n = 1), and arrhythmia (n = 1). There were no extubation failures in patients extubated >24 hrs after surgery. A history of prematurity (odds ratio [OR], 5.84, 2.29–14.9; p < .001), base excess (OR, 1.47, 1.27–1.70; p < .001), cardiopulmonary bypass time (OR, 1.01, 1.01 to −1.2; p < .05), and the need for surgical reintervention (OR, 18.29, 2.78 to −120.07; p < .05) were associated with intubation for >24 hrs. Conclusion: Extubation without the need for reintubation can be achieved in nearly all children following cardiothoracic surgery. The majority of successful extubations can be achieved within 24 hrs of surgery.

Activated partial thromboplastin time is a better trending tool in pediatric extracorporeal membrane oxygenation

Objectives: To determine whether activated partial thromboplastin times are a better heparin management tool than activated clotting times in pediatric extracorporeal membrane oxygenation. Design: A single-center retrospective analysis of perfusion and patient records. Setting: Academic pediatric tertiary care center. Patients: Pediatric patients (<21 yrs old) requiring extracorporeal membrane oxygenation support initiated at Children’s Hospital of Pittsburgh. Interventions: None. Measurements and Main Results: Point-of-care activated clotting time and activated partial thromboplastin time values, clinical laboratory activated partial thromboplastin time values, weight-normalized heparin administration (units/kg/hr), and reported outcomes were collected for pediatric patients treated for cardiac and/or respiratory failure with extracorporeal membrane oxygenation. Spearman’s ranked correlations were performed for each coagulation test compared to heparin dosage. The Bland–Altman test was used to determine the validity of the point-of-care activated partial thromboplastin time. Hazard analysis was conducted for outcomes and complications for patients whose heparin management was based on the clinical laboratory activated partial thromboplastin time or the activated clotting time. Only the clinical laboratory activated partial thromboplastin time showed a correlation (&rgr; = 0.40 vs. &rgr; = −0.04 for activated clotting time) with the heparin administration (units/kg/hr). Point-of-care activated partial thromboplastin time and activated partial thromboplastin time values correlated well (&rgr; = 0.76), with <5% of samples showing a difference outside 2 SDs, but differences in their absolute values (&Dgr;activated partial thromboplastin time = 100 secs) preclude them from being interchangeable measures. Furthermore, despite no effective change in the mean activated clotting time, cardiac patients showed a significantly improved correlation to heparin dose for all coagulation tests (e.g., point-of-care activated partial thromboplastin time &rgr; = 0.60). Management of patients with the clinical laboratory activated partial thromboplastin time did not significantly affect patient survival rates but did significantly reduce bleeding complications and significantly increased clotting in the extracorporeal membrane oxygenation circuit. A hazard analysis demonstrated that bleeding complications were associated with an increased risk of mortality, whereas clotting complications in the extracorporeal membrane oxygenation circuit were not. Conclusions: The activated clotting time is not an accurate monitoring tool for heparin management in pediatricextracorporeal membrane oxygenation. The point-of-care activated partial thromboplastin time correlates well with the clinical laboratory activated partial thromboplastin time but cannot be substituted for the clinical laboratory activated partial thromboplastin time values. Management of pediatric extracorporeal membrane oxygenation patients with the clinical laboratory activated partial thromboplastin time reduced bleeding complications which are associated with increases in mortality.

Diastolic hypotension is an unrecognized risk factor for β-agonist-associated myocardial injury in children with asthma.

Objectives: Tachycardia and diastolic hypotension have been associated with &bgr;-2 agonist use. In the setting of &bgr;-agonist-induced chronotropy and inotropy, diastolic hypotension may limit myocardial blood flow. We hypothesized that diastolic hypotension is associated with &bgr;-agonist use and that diastolic hypotension and tachycardia are associated with biochemical evidence of myocardial injury in children with asthma. Design: Two patient cohorts were collected. The first, consisting of patients transported for respiratory distress having received at least 10 mg of albuterol, was studied for development of tachycardia and hypotension. The second, consisting of patients who had troponin measured during treatment for status asthmaticus with continuous albuterol, was studied for factors associated with elevated troponin. Exclusion criteria for both cohorts included age younger than 2 years old, sepsis, pneumothorax, cardiac disease, and antihypertensive use. Albuterol dose, other medications, and vital signs were collected. Diastolic and systolic hypotension were defined as an average value below the fifth percentile for age and tachycardia as average heart rate above the 98th percentile for age. Patients: Ninety of 1,390 children transported for respiratory distress and 64 of 767 children with status asthmaticus met inclusion criteria. Measurements and Main Results: Diastolic hypotension occurred in 56% and 98% of the first and second cohorts, respectively; tachycardia occurred in 94% and 95% of the first and second cohorts, respectively. Diastolic hypotension and tachycardia had a weak linear correlation with albuterol dose (p = 0.02 and p = 0.005, respectively). Thirty-six percent had troponin > 0.1 ng/mL (range, 0–12.6). In multivariate analysis, interaction between diastolic hypotension and tachycardia alone was associated with elevated troponin (p = 0.02). Conclusions: Diastolic hypotension and tachycardia are dose-dependent side effects of high-dose albuterol. In high-risk patients with status asthmaticus treated with albuterol, diastolic hypotension and tachycardia are associated with biochemical evidence of myocardial injury. Diastolic hypotension, especially combined with tachycardia, could be a reversible risk factor for myocardial injury related to &bgr;-agonist use.

Development of Risk Indices for Neonatal Respiratory Extracorporeal Membrane Oxygenation

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) has saved thousands of newborns. Population comparisons for research and quality initiatives require risk-matching, but no indices exist for this population. We sought to create a pre-ECMO risk index using the registry data from the Extracorporeal Life Support Organization. We analyzed 5,455 neonatal (<30 days old) respiratory VA-ECMO patients for the period 2000–2010. Multivariate regression examining the impact of pre-ECMO variables on survival to hospital discharge was performed to create the Pittsburgh Index for Pre-ECMO Risk (PIPER), which was ultimately was based on seven pre-ECMO variables. Each PIPER quartile demonstrated increasing mortality by 15% (R2 = 0.98) and was associated with increased complications on ECMO. Further modeling to include on-ECMO complications (PIPER+), including complications and length of time on ECMO, increased the predictive power of the model, with 21% increases in mortality per PIPER+ quartile (R2 = 0.97). Our developed indices provide the first steps towards risk-adjusting patients for meaningful comparisons amongst patient populations. There may be additional clinically relevant measures, both pre- and on-ECMO, which could provide better predictive capability. Future work will focus on finding these additional measures and expansion of our techniques to include other patient populations.

Unplanned Transport Events and Severity of Illness: Are We Conveying the Whole Picture?

immunoreactive trypsinogen/DNA cystic fibrosis (CF) newborn screen with a F508/R117H-7T genotype who grew Pseudomonas aeruginosa from an oropharyngeal culture and demonstrated airway obstruction on infant pulmonary-function testing. We believe these 5 cases, along with those reported by Lording et al,2 supply ample evidence that the F508/R117H-7T genotype is not necessarily benign. This experience contrasts with the conclusions of the report by Scotet et al3 in the November issue of Pediatrics. They reported a series of infants with elevated immunoreactive trypsinogen and the F508/ R117H-7T genotype and concluded that there was significantly better pulmonary function in the R117H compound heterozygotes as compared with age-matched controls with 2 severe CF mutations. Unfortunately, FEV1 (forced expiratory volume in 1 second) data were only available for 2 of 9 R117H compound heterozygotes. Also, although only 1 of 9 R117H compound heterozygotes versus 5 of 9 controls grew P aeruginosa from respiratory cultures, the authors did not state how many of the R117H compound heterozygotes had sputum or oropharyngeal cultures obtained or how frequently they were obtained. Scotet et al3 recommend removal of R117H from the CF newborn screening mutation panel on the basis of this very limited data set. Our findings,1 as well as those of Ren and Lording et al,2 demonstrate that children with this mutation are at some risk of Pseudomonas colonization and infection, respiratory symptoms, and abnormal pulmonary-function test results. We believe it is premature to recommend removal of R117H from CF newborn screening mutation panels. Larger longitudinal studies need to be performed. We continue to recommend that all infants identified with R117H-7T as 1 of 2 CF transmembrane conductance regulator (CFTR) mutations be followed by a CF clinician, including evaluation for CF flora, chest imaging, and pulmonary-function testing, when it can be performed.

Inhaled Pulmonary Vasodilators: Are There Indications Within the Pediatric ICU?

Inhaled nitric oxide (INO) is only FDA-cleared for neonates (> 34 weeks gestation) with hypoxic respiratory failure-associated pulmonary hypertension. Off-label use of INO is common in the pediatric population despite a lack of evidence regarding survival benefit, questioning whether the therapy should be considered outside the neonatal period. A lack of definitive evidence combined with increasing health-care costs has led to the use of less costly inhaled prostacyclin as an alternative to INO, presenting unique patient safety concerns. We evaluate the current evidence and patient safety considerations regarding inhaled pulmonary vasodilators in the pediatric population.

Interfacility Transport Shock Index Is Associated With Decreased Survival in Children

Background Shock index, the ratio of heart rate to systolic blood pressure that changes with age, is associated with mortality in adults after trauma and in children with sepsis. We assessed the utility of shock index to predict sepsis diagnosis and survival in children requiring interfacility transport to a tertiary care center. Methods We studied children aged 1 month to 21 years who had at least 2 sets of vital signs recorded during interfacility transport to the Children’s Hospital of Pittsburgh by our critical care transport team. Subjects were divided into 4 age groups: group 1 (<1 year), group 2 (1–3 years), group 3 (4–11 years), and group 4 (≥12 years). Children were also grouped into sepsis or nonsepsis group based on the International Classification of Diseases, Ninth Revision categories. Primary outcome was survival to hospital discharge. Results Of 3519 children studied, 493 (14%) had sepsis. Initial shock index decreased with increasing age: group 1, 1.45 ± 0.42 (mean ± SD); group 2, 1.35 ± 0.32; group 3, 1.20 ± 0.34; and group 4, 1.00 ± 0.32 (P < 0.001). Initial shock index was increased in children with sepsis versus those with no sepsis overall and in all age groups (all P < 0.05). Initial shock index showed a trend for association with survival in univariate analysis (P = 0.05) but was not associated with survival in a multivariable logistic regression. Highest quartile of shock index was associated with need for intensive care unit admission posttransport. Conclusions Increased shock index in children requiring intrafacility transport was associated with hospital discharge diagnosis of sepsis but not hospital survival.