Non-invasive ventilation for severe bronchiolitis: analysis and evidence.

OBJECTIVES: (1) To examine whether infants with severe bronchiolitis, fulfilling criteria for further respiratory support, could be managed outside a Pediatric Intensive Care Unit (PICU) with non-invasive ventilation (NIV) alone. (2) To study the characteristics, clinical course and outcome of NIV responders and non responders to assess safety and efficacy and inform guideline construction. HYPOTHESIS: Infants with severe bronchiolitis can be safely managed with NIV outside a PICU. STUDY DESIGN: Retrospective case review. PATIENT SELECTION: Cohort of infants with objective evidence of severe bronchiolitis requiring respiratory support nursed in a Pediatric High Dependency Unit (PHDU) and/or Intensive Care Unit (ICU) between 2001 and 2007. METHODOLOGY: Analysis of patient characteristics and respiratory parameters at admission and initiation of ventilation, changes after 2 and 4 hr of NIV or invasive ventilation, complications, short and long-term outcomes were analyzed. RESULTS: One thousand and thirty-five infants with bronchiolitis were admitted with 67 ventilation episodes identified from 65 patients. Fifty-five episodes, including 34 with apnea, were treated exclusively with NIV. Six infants failed to respond and were invasively ventilated. Six patients were invasively ventilated at presentation. Non-responders had a significantly higher rate of bacterial infection. Significant improvements in respiratory parameters in responders occurred by 2 hr and sustained at 4 hr. Duration of hospital stay, ventilation requirement and oxygen requirement were significantly shorter in responders. Short and longer-term follow up data did not identify any adverse effects related to NIV. CONCLUSIONS: NIV was effective in 80% of infants receiving respiratory support for severe bronchiolitis.

Comparison of sepsis definitions in a resource poor environment.

Sepsis is an important cause of childhood death in developing countries. The International Pediatric Sepsis Consensus Conference (IPSCC) guidelines for definition has five categories and requires complex information, which may be difficult to access in resource poor settings, possibly leading to under-diagnosis and problems with triage, referral and documentation for public health assessments. We aimed to provide a workable system for grading sepsis categories, assess this against the IPSCC definition and use this information to guide further adaptations. We conducted a prospective observational study of consecutive admissions to a pediatric intensive care unit of a public hospital between August and September 2006. We recorded history and demographic, clinical, investigative, treatment and outcome details. We compared the performance of the IPSCC scoring system to the modified system. We studied one hundred consecutive admissions and collected data for the modified format. The distribution of sepsis cases and (deaths) was as follows: systemic inflammatory response syndrome 26 (2), sepsis 30 (5), severe sepsis/septic shock 15 (11), organ dysfunction 2 (2) and no sepsis 27 (3). Overall mortality was 23%. Despite its simplicity, the modified system corresponded well to the IPSCC system except for the systemic inflammatory response syndrome category. We suggest adaptations to improve agreement with IPSCC whilst maintaining ease of use. It is possible to simplify the IPSCC score to provide information in a resource poor setting but only further studies will be able to assess robustness in the field.

Fulminant pertussis: a multi-center study with new insights into the clinico-pathological mechanisms.

Pertussis carries a high risk of mortality in very young infants. The mechanism of refractory cardio-respiratory failure is complex and not clearly delineated. We aimed to examine the clinico-pathological features and suggest how they may be related to outcome, by multi-center review of clinical records and post-mortem findings of 10 patients with fulminant pertussis (FP). All cases were less than 8 weeks of age, and required ventilation for worsening respiratory symptoms and inotropic support for severe hemodynamic compromise. All died or underwent extra corporeal membrane oxygenation (ECMO) within 1 week. All had increased leukocyte counts (from 54 to 132 x 10(9)/L) with prominent neutrophilia in 9/10. The post-mortem demonstrated necrotizing bronchitis and bronchiolitis with extensive areas of necrosis of the alveolar epithelium. Hyaline membranes were present in those cases with viral co-infection. Pulmonary blood vessels were filled with leukocytes without well-organized thrombi. Immunodepletion of the thymus, spleen, and lymph nodes was a common feature. Other organisms were isolated as follows; 2/10 cases Para influenza type 3, 2/10 Moraxella catarrhalis, 1/10 each with respiratory syncytial virus (RSV), a coliform organism, methicillin-resistant Staphylococcus aureus (MRSA), Haemophilus influenzae, Stenotrophomonas maltophilia, methicillin-sensitive Staphylococcus aureus (MSSA), and candida tropicalis. We postulate that severe hypoxemia and intractable cardiac failure may be due to the effects of pertussis toxin, necrotizing bronchiolitis, extensive damage to the alveolar epithelium, tenacious airway secretions, and possibly leukostasis with activation of the immunological cascade, all contributing to increased pulmonary vascular resistance. Cellular apoptosis appeared to underlay much of these changes. The secondary immuno-compromise may facilitate co-infection.

Heliox with inhaled nitric oxide: a novel strategy for severe localized interstitial pulmonary emphysema in preterm neonatal ventilation.

We describe the combined use of inhaled nitric oxide and heliox (79% helium and 21% oxygen) as a rescue therapy for a critically ill infant with localized interstitial pulmonary emphysema and pulmonary hypertension. Conventional interventions were ineffective, not feasible, or unlikely to take effect in time, during this infant's acute critical illness. We added heliox based on its known pulmonary effects, and inhaled nitric oxide to improve oxygenation, after echocardiographic evidence of high right-ventricular pressure. The infant made a full recovery. To our knowledge this is the first case report of heliox and inhaled nitric oxide used simultaneously in localized interstitial pulmonary emphysema.

The role of noninvasive ventilation for acute respiratory failure.

The use of NIV has been shown to facilitate discontinuing ventilatory dependence as well as provide support for adult patients with chronic lung disease without the need for endotracheal intubation. In fact, NIV has recently described as a potential support strategy following extubation failure. Therefore, using NIV as a bridge to liberation from mechanical ventilation may decrease many of the complications associated with long-term use of invasive airway devices as well complications from reinsertion of an artificial airway. Although firm data supporting the use of NIV in the adult population exists, the use of NIV in the pediatric population is based primarily on a series of case studies, retrospective chart reviews, and extrapolation from the adult data. The use of NIV for infants and children remains controversial. The important question to be asked is why there is a lack of randomized controlled trials on NIV in pediatrics? The answer lies somewhere between the lack of equipment designed specifically for pediatrics and the smaller number of patients available compared with adults. Data from the adult population may be more readily adapted to older children; however, it remains difficult to determine the criteria for noninvasive ventilatory use in infants and young children. In fact, this lack of data makes the formulation of firm selection guidelines for infants and children essentially impossible. However, for a select groups of pediatric patients with acute respiratory failure for whom an appropriate noninvasive device with interface is available, a trial of NIV may be seem reasonable to avoid the known negative effects of intubation and invasive mechanical ventilation.