Duncan Macrae

Inhaled nitric oxide therapy in neonates and children: reaching a European consensus

Inhaled nitric oxide (iNO) was first used in neonatal practice in 1992 and has subsequently been used extensively in the management of neonates and children with cardiorespiratory failure. This paper assesses evidence for the use of iNO in this population as presented to a consensus meeting jointly organised by the European Society of Paediatric and Neonatal Intensive Care, the European Society of Paediatric Research and the European Society of Neonatology. Consensus Guidelines on the Use of iNO in Neonates and Children were produced following discussion of the evidence at the consensus meeting.

Inhaled nitric oxide therapy in adults: European expert recommendations.

BackgroundInhaled nitric oxide (iNO) has been used for treatment of acute respiratory failure and pulmonary hypertension since 1991 in adult patients in the perioperative setting and in critical care.MethodsThis contribution assesses evidence for the use of iNO in this population as presented to a expert group jointly organised by the European Society of Intensive Care Medicine and the European Association of Cardiothoracic Anaesthesiologists.ConclusionsExpert recommendations on the use of iNO in adults were agreed on following presentation of the evidence at the expert meeting held in June 2004.

Challenge of predicting resting energy expenditure in children undergoing surgery for congenital heart disease.

Objectives: To determine pre- and postoperative predictors of energy expenditure in children with congenital heart disease requiring open heart surgery; and to compare measured resting energy expenditure with current predictive equations. Design: Prospective resting energy expenditure data were collected, using indirect calorimetry, for ventilated children admitted consecutively to the pediatric intensive care unit after surgery for congenital heart disease. A 30-min steady-state measurement was performed in suitable patients. Resting energy expenditure was compared to pre- and postoperative clinical variables, and to predicted energy expenditure, using currently used predictive equations. Setting: Pediatric intensive care unit at the Royal Brompton Hospital, London. Patients: Children ventilated in the pediatric intensive care unit post surgery for congenital heart disease. Interventions: Measurement of energy expenditure by indirect calorimetry. Measurements and Main Results: Twenty-one mechanically ventilated children (n = 17 boys, 4 girls) were enrolled in the study. Mean ± sd measured resting energy expenditure was 67.8 ± 15.4 kcal/kg/day. Most children had inadequate delivery of nutrients compared with actual requirements. Cardiopulmonary bypass had a significant influence on energy expenditure after surgery; in patients who underwent cardiopulmonary bypass during surgery, mean resting energy expenditure was 73.6 ± 14.45 kcal/kg/day vs. 58.3 ± 10.29 kcal/kg/day in patients undergoing nonbypass surgery. Children who were malnourished preoperatively had greater resting energy expenditure postoperatively. There was also a significant difference between measured energy expenditure and the Schofield (p = .006), World Health Organization (p = .002), and pediatric intensive care unit-specific formula (p < .0001). However, energy expenditure or a relative energy deficit in the early postoperative period was not associated with severity or duration of organ dysfunction. Conclusions: Poor nutritional status preoperatively and cardiopulmonary bypass were associated with a greater energy expenditure post cardiac surgery. None of the current predictive equations predicted energy requirements within acceptable clinical accuracy.

Nitric oxide 2

Introduction: Permissive hypercapnia (PH) is a beneficial strategy for patients with acute respiratory distress syndrome (ARDS) to minimize barotrauma by decreasing the peak inspiratory pressure (PIP). Hypercapnia and hypoxia cause pulmonary vasoconstriction, pulmonary artery (PA) hypertension, and, thus, an increased afterload to the right ventricle. This increased afterload may result in increased right ventricular (RV) work load and subsequent RV dysfunction. One therapeutic approach is the use of inhaled nitric oxide (iNO), a selective PA vasodilator. The objectives of this study were to test the hypothesis that in a swine model of ARDS with PH, iNO would improve RV work load and not change intrinsic RV contractility. Methods: In 11 swine (25-35 kg), ARDS was induced by surfactant depletion. Hypercapnia was achieved by decreasing the PIP while increasing the PEEP to maintain a constant mean airway pressure. iNO was administered in concentrations of 2, 5, and 10 ppm in a random order, Pulmonary blood flow (Qpa) was determined by an ultrasonic flow probe. RV total power (TP) and stroke work (SW) were calculated by Fourier transformation of the PA pressure (Ppa) and Qpa data. Preload recruitable stroke work (PRSW), a preload and afterload independent measure of ventricular contractility, was determined by a shell-subtraction method and vena caval occlusion) Results: Data are represented as mean ± sent and compared by two-way analysis of variance with repeated measures. (* n < 0.05 vs. 0 nnm) 0 ppm 2 ppm 5 ppm 10 ppm er s*1000 /mL 24.6 ± 1.6 25.2 ± 2.4 23.3 ± 1.8 22.9 ± 2.5 mW 92±11 74±6* 66±6 75±8* [RSW

Anti-inflammatory modalities: Their current use in pediatric cardiac surgery in the United Kingdom and Ireland*

Objective: To determine the use of anti-inflammatory therapies in infants and children undergoing cardiac surgery in the United Kingdom and Ireland. Design: Questionnaire survey. Subjects: All centers that undertake pediatric cardiac surgery in the United Kingdom and Ireland. Results: All centers use at least one anti-inflammatory therapy, with 46% of centers using more than one. Both modified ultrafiltration (80%) and steroids (80%) are widely used as anti-inflammatory strategies. Among centers that use steroids, dose, preparation, and timing of steroid administered was highly variable. Heparin-bonded circuits and aprotinin are infrequently used as anti-inflammatory techniques. Conclusion: Although anti-inflammatory interventions are believed to contribute to improved patient outcome following cardiopulmonary bypass, this survey has shown that there are still widespread variations in practice. Rather than reflecting poor clinical practice, we believe this reflects a lack of good evidence supporting clinical benefit.

Nutritional status and clinical outcome in postterm neonates undergoing surgery for congenital heart disease.

Objective: Poor growth is a common complication in infants with congenital heart disease. There has been much focus on low birth weight as having increased risk of adverse outcomes following neonatal heart surgery. In this study, we examined whether preoperative nutritional status, measured by admission weight-for-age z score, was associated with postoperative clinical outcome. Design: Retrospective case series. Setting: Pediatric Cardiac ICU at the Royal Brompton Hospital. Patients: Neonates undergoing surgery for congenital heart disease. Those undergoing ductus arteriosus ligation alone were excluded. Children with coexisting noncardiac morbidity were excluded. Outcome variables included prevalence of postoperative complications (including sepsis, delayed chest closure, renal impairment, and necrotizing enterocolitis), duration of ventilation, intensive care stay, postoperative mortality, and mortality at 1 year after surgery. Interventions: None. Analysis of patient data only. Measurements and Main Results: Two hundred forty-eight neonates fulfilled the entry criteria. Median (interquartile range) age was 7 days (2–15 d), median (interquartile range) weight was 3.3 kg (2.91–3.6 kg), and median weight-for-age z score was –0.77 (–1.44 to 0.01). Twenty-eight children (11%) had a weight-for-age z score of less than –2. There was no evidence that children with lower weight-for-age z score had less severe surgery as measured by the Risk Adjustment for Congenital Heart Surgery 1 score. In multivariable regression analysis, the weight-for-age z at admission had strong correlation with the number of days free of respiratory support (invasive and noninvasive ventilation) at 28 days (p < 0.0001) and with all-cause mortality at 1 year (p = 0.001). Conclusions: Poor nutritional status as measured by weight-for-age z is associated with adverse short- and long-term outcomes in neonates undergoing surgery for congenital heart disease.

Surfactant adjunctive therapy for Pneumocystis carinii pneumonitis in an infant with acute lymphoblastic leukaemia.

We report successful treatment of adult respiratory distress syndrome (ARDS) with artificial surfactant (40mg/kg, Colfosceril Palmitate, ‘Exosurf’, Wellcome) in an infant with severePneumocystis carinii pneumonitis.

Year in review in Intensive Care Medicine 2009: I. Pneumonia and infections, sepsis, outcome, acute renal failure and acid base, nutrition and glycaemic control

Year in review in Intensive Care Medicine 2009 : I. Pneumonia and infections, sepsis, outcome, acute renal failure and acid base, nutrition and glycaemic control

Inhaled Nitric Oxide and Related Therapies

Children with congenital heart defects are at risk for perioperative pulmonary hypertension if they require corrective or palliative surgery in the first week of life or if they have defects associated with significant pulmonary overcirculation. In addition, children undergoing cavopulmonary connections for single ventricle lesions require low pulmonary vascular resistance for surgical success. Treatment of perioperative pulmonary hypertension with inhaled nitric oxide has become standard therapy in many centers. Related drugs that increase nitric oxide synthesis, including arginine and citrulline, have also been studied in the perioperative period. In this article, previous clinical trials of inhaled nitric oxide, intravenous arginine, and intravenous and oral citrulline in children with perioperative pulmonary hypertension or elevated pulmonary vascular resistance after a cavopulmonary connection are reviewed. In addition, recommendations are presented for each agent on the clinical use in the perioperative setting including clinical indications, assessment of clinical effect, and length of therapy.

Extracorporeal support in children with pediatric acute respiratory distress syndrome: proceedings from the Pediatric Acute Lung Injury Consensus Conference.

Objective: Extracorporeal life support has undergone a revolution in the past several years with the advent of new, miniaturized equipment and success in supporting patients with a variety of illnesses. Most experience has come with the use of extracorporeal membrane oxygenation, a modified form of cardiopulmonary bypass that can support the heart, lungs, and circulation for days to months at a time. To describe the recommendations for the use of extracorporeal membrane oxygenation in children with pediatric acute respiratory distress syndrome based on a review of the literature and expert opinion. Design: Consensus conference of experts in pediatric acute lung injury. Methods: A panel of 27 experts met over the course of 2 years to develop a taxonomy to define pediatric acute respiratory distress syndrome and to make recommendations regarding treatment and research priorities. The extracorporeal support subgroup comprised two international experts. When published data were lacking, a modified Delphi approach emphasizing strong professional agreement was used. Results: The Pediatric Acute Lung Injury Consensus Conference experts developed and voted on a total of 151 recommendations addressing the topics related to pediatric acute respiratory distress syndrome, 11 of which related to extracorporeal support. All recommendations had agreement, with 10 recommendations (91%) achieving strong agreement. These recommendations included the utilization of extracorporeal support for reversible causes of pediatric acute respiratory distress syndrome, consideration of quality of life when making the decision to use extracorporeal support, and the use of the Extracorporeal Life Support Organization registry to report all extracorporeal support activity, among others. Conclusions: Pediatric extracorporeal membrane oxygenation for pediatric acute respiratory distress syndrome could benefit from more specific data collection and collaboration of focused investigators to establish validated criteria for optimal application of extracorporeal membrane oxygenation and patient management protocols. Until that time, consensus opinion offers some insight into guidelines.