Andreas Schibler

Acute lung injury in pediatric intensive care in Australia and New Zealand: a prospective, multicenter, observational study

Objective: Acute lung injury (ALI) is poorly defined in children. The objective of this prospective study was to clarify the incidence, demographics, management strategies, outcome, and mortality predictors of ALI in children in Australia and New Zealand. Design: Multicenter prospective study during a 12-month period. Setting: Intensive care unit. Patients: All children admitted to intensive care and requiring mechanical ventilation were screened daily for development of ALI based on American-European Consensus Conference guidelines. Identified patients were followed for 28 days or until death or discharge. Interventions: None. Measurements and Main Results: There were 117 cases of ALI during the study period, giving a population incidence of 2.95/100,000 <16 yrs. ALI accounted for 2.2% of pediatric intensive care unit admissions. Mortality was 35% for ALI, and this accounted for 30% of all pediatric intensive care unit deaths during the study period. Significant preadmission risk factors for mortality were chronic disease, older age, and immunosuppression. Predictors of mortality during admission were ventilatory requirements (peak inspiratory pressures, mean airway pressure, positive end-expiratory pressure) and indexes of respiratory severity on day 1 (Pao2/Fio2 ratio and oxygenation index). Higher maximum and median tidal volumes were associated with reduced mortality, even when corrected for severity of lung disease. Development of single and multiple organ failure was significantly associated with mortality. Conclusions: ALI in children is uncommon but has a high mortality rate. Risk factors for mortality are easily identified. Ventilatory variables and indexes of lung severity were significantly associated with mortality.

Synovitis, acne, pustulosis, hyperostosis, osteitis (SAPHO) syndrome in childhood: a report of ten cases and review of the literature.

Abstract Chronic recurrent multifocal osteomyelitis is a rare chronic inflammatory musculoskeletal process observed in children and young adults. Recently, the acronym SAPHO syndrome (for synovitis, acne, pustulosis, hyperostosis, osteitis) was coined to emphasise the association between osteo-articular inflammations and different skin abnormalities which are aseptic and filled with neutrophils. In adults, chronic recurrent multifocal osteomyelitis is now a classical manifestation of SAPHO syndrome. Chronic skin disorders were seen in eight of ten children on follow-up at the University Childrens Hospitals in Bern and Zurich and in 61 of 260 paediatric cases reported in the literature. The different skin lesions were palmoplantar pustulosis (n=40), non-palmoplantar pustulosis (n=6), psoriasis vulgaris (n=16) or severe acne (n=4). More rarely Sweet syndrome (n=2) or pyoderma gangrenosum (n=1) were reported. Conclusion The synovitis, acne, pustulosis, hyperostosis, osteitis syndrome is pertinent even in paediatrics since skin involvement is frequent.

Measurement of lung volume and ventilation distribution with an ultrasonic flow meter in healthy infants

Small airway disease in infants is characterised by abnormal lung volume and uneven ventilation distribution. An inert tracer gas washin/washout technique using a pulsed ultrasonic flow meter is presented to measure functional residual capacity (FRC) and ventilation distribution in spontaneously breathing and unsedated infants. With a pulsed ultrasound sent through the main stream of the flow meter, flow, volume and MM of the breathing gas can be calculated. Sulphur hexafluoride was used as a tracer gas. In a mechanical lung model (volume range 53–188 mL) and in 12 healthy infants (aged 38.3±9.2 days; mean±sd) accuracy and reproducibility of the technique was assessed. Indices of ventilation distribution such as alveolar-based mean dilution number (AMDN) and pulmonary clearance delay (PCD) were calculated. Mean error of volume measurement in the lung model was 0.58% (coefficient of variance (CV) 1.3%). FRC was in the low predicted range for normal infants (18.0±2.0 mL·kg−1) and highly reproducible (5.5±1.7% intra-subject CV). AMDN was 1.63±0.15 and PCD was 52.9±11.1%. Measurement of functional residual capacity and ventilation distribution using a sulphur hexafluoride washin/washout and an ultrasonic flow meter proved to be highly accurate and reproducible in a lung model and in healthy, spontaneously breathing and unsedated infants.

High-flow nasal cannula oxygen therapy for infants with bronchiolitis: Pilot study

To obtain data on the safety and clinical impact of managing infants with bronchiolitis on the ward with high‐flow nasal cannula (HFNC) treatment.

The effect of high flow nasal cannula therapy on the work of breathing in infants with bronchiolitis

The main physiological impact of high flow nasal cannula (HFNC) therapy is presumed to be a decrease in work of breathing (WOB). To assess this, diaphragmatic electrical activity and esophageal pressure changes were measured off then on HFNC delivered at 2 L/kg/min, in 14 infants with bronchiolitis and 14 cardiac infants. Electrical activity of the diaphragm (Edi) was measured using an Edi catheter with calculations of signal peak (EdiMAX) and amplitude (EdiAMPL). Pressure–rate and pressure–time products (PRP, PTP) were calculated from analyses of esophageal pressure. Changes in end‐expiratory lung volume were measured using respiratory inductance plethysmography (RIPEEL). The EdiMAX and EdiAMPL were significantly higher in infants with bronchiolitis than in cardiac infants (P < 0.05). Within the bronchiolitis group, both were significantly reduced between HFNC states from 27.9 µV [20.4, 35.4] to 21.0 µV [14.8, 27.2] and from 25.1 µV [18.0, 32.2] to 19.2 µV [13.3, 25.1], respectively (mean, 95% CI, P < 0.05). A less prominent offload of the diaphragm was observed in cardiac infants (P < 0.05). WOB decreased in both groups with a significant reduction of PRP and PTP (P < 0.05). RIPEEL increased significantly in bronchiolitis only (P < 0.05). HFNC offloads the diaphragm and reduces the WOB in bronchiolitis. A similar effect was demonstrated in cardiac infants, a group without signs of airway‐obstruction. Pediatr Pulmonol. 2015; 50:713–720.

Chest electrical impedance tomography examination, data analysis, terminology, clinical use and recommendations: consensus statement of the TRanslational EIT developmeNt stuDy group

Electrical impedance tomography (EIT) has undergone 30 years of development. Functional chest examinations with this technology are considered clinically relevant, especially for monitoring regional lung ventilation in mechanically ventilated patients and for regional pulmonary function testing in patients with chronic lung diseases. As EIT becomes an established medical technology, it requires consensus examination, nomenclature, data analysis and interpretation schemes. Such consensus is needed to compare, understand and reproduce study findings from and among different research groups, to enable large clinical trials and, ultimately, routine clinical use. Recommendations of how EIT findings can be applied to generate diagnoses and impact clinical decision-making and therapy planning are required. This consensus paper was prepared by an international working group, collaborating on the clinical promotion of EIT called TRanslational EIT developmeNt stuDy group. It addresses the stated needs by providing (1) a new classification of core processes involved in chest EIT examinations and data analysis, (2) focus on clinical applications with structured reviews and outlooks (separately for adult and neonatal/paediatric patients), (3) a structured framework to categorise and understand the relationships among analysis approaches and their clinical roles, (4) consensus, unified terminology with clinical user-friendly definitions and explanations, (5) a review of all major work in thoracic EIT and (6) recommendations for future development (193 pages of online supplements systematically linked with the chief sections of the main document). We expect this information to be useful for clinicians and researchers working with EIT, as well as for industry producers of this technology.

Mortality related to invasive infections, sepsis, and septic shock in critically ill children in Australia and New Zealand, 2002–13: a multicentre retrospective cohort study

BACKGROUND Severe infections kill more than 4·5 million children every year. Population-based data for severe infections in children requiring admission to intensive care units (ICUs) are scarce. We assessed changes in incidence and mortality of severe infections in critically ill children in Australia and New Zealand. METHODS We did a retrospective multicentre cohort study of children requiring intensive care in Australia and New Zealand between 2002 and 2013, with data from the Australian and New Zealand Paediatric Intensive Care Registry. We included children younger than 16 years with invasive infection, sepsis, or septic shock. We assessed incidence and mortality in the ICU for 2002-07 versus 2008-13. FINDINGS During the study period, 97 127 children were admitted to ICUs, 11 574 (11·9%) had severe infections, including 6688 (6·9%) with invasive infections, 2847 (2·9%) with sepsis, and 2039 (2·1%) with septic shock. Age-standardised incidence increased each year by an average of 0·56 cases per 100 000 children (95% CI 0·41-0·71) for invasive infections, 0·09 cases per 100 000 children (0·00-0·17) for sepsis, and 0·08 cases per 100 000 children (0·04-0·12) for septic shock. 260 (3·9%) of 6688 patients with invasive infection died, 159 (5·6%) of 2847 with sepsis died, and 346 (17·0%) of 2039 with septic shock died, compared with 2893 (3·0%) of all paediatric ICU admissions. Children admitted with invasive infections, sepsis, and septic shock accounted for 765 (26·4%) of 2893 paediatric deaths in ICUs. Comparing 2008-13 with 2002-07, risk-adjusted mortality decreased significantly for invasive infections (odds ratio 0·72, 95% CI 0·56-0·94; p=0·016), and for sepsis (0·66, 0·47-0·93; p=0·016), but not significantly for septic shock (0·79, 0·61-1·01; p=0·065). INTERPRETATION Severe infections remain a major cause of mortality in paediatric ICUs, representing a major public health problem. Future studies should focus on patients with the highest risk of poor outcome, and assess the effectiveness of present sepsis interventions in children. FUNDING National Medical Health and Research Council, Australian Resuscitation Outcomes Consortium, Centre of Research Excellence (1029983).

The value of electrical impedance tomography in assessing the effect of body position and positive airway pressures on regional lung ventilation in spontaneously breathing subjects

ObjectiveFunctional electrical impedance tomography (EIT) measures relative impedance changes in lung tissue during tidal breathing and creates images of local ventilation distribution. A novel approach to analyse the effect of body position and positive pressure ventilation on intrapulmonary tidal volume distribution was evaluated in healthy adult subjects.Design and settingProspective experimental study in healthy adult subjects in the intensive care unit at university hospital.SubjectsTen healthy male adults.InterventionsChange in body position from supine to prone, left and right lateral during spontaneous breathing and positive pressure support ventilation.Measurements and resultsEIT measurements and multiple-breath sulphur hexafluoride (SF6) washout were performed. Profiles of average relative impedance change in regional lung areas were calculated. Relative impedance time course analysis and Lissajous figure loop analysis were used to calculate phase angles between dependent or independent lung and total lung (φ). EIT data were compared to SF6 data washout measuring the lung clearance index (LCI). Proposed EIT profiles allowed inter-individual comparison of EIT data and identified areas with reduced regional tidal volume using pressure support ventilation. Phase angle φ of dependent lung in supine position was 11.7±1.4°, in prone 5.3±0.5°, in right lateral 11.0±1.3° and in left lateral position 10.8±1.0°. LCI increased in supine position from 5.63±0.43 to 7.13±0.64 in prone position. Measured φ showed inverse relationship to LCI in the four different body positions.ConclusionsEIT profiles and φ of functional EIT are new methods to describe regional ventilation distribution with EIT allowing inter-individual comparison.

Decrease of functional residual capacity and ventilation homogeneity after neuromuscular blockade in anesthetized young infants and preschool children

Background: Based on age-dependent differences in pulmonary mechanics, the effect of neuromuscular blockade may differ in infants compared with older children. The aim of this study was to determine the impact of neuromuscular blockade and its reversal by positive end-expiratory pressure (PEEP) on functional residual capacity (FRC) and ventilation distribution in young infants and preschool children. Methods: The authors studied 14 infants (aged 0–6 months) and 25 preschool children (aged 2–6 yr). FRC and lung clearance index were calculated. Measurements were taken (1) after intubation, (2) during neuromuscular blockade, and (3) during neuromuscular blockade plus application of PEEP (3 cm H2O). Results: Functional residual capacity (mean ± SD) decreased from 21.3 ± 4.7 ml/kg to 12.2 ± 4.8 ml/kg (P < 0.001) during neuromuscular blockade in infants and from 25.6 ± 5.9 ml/kg to 23.0 ± 5.3 ml/kg (P < 0.001) in preschool children. With the application of PEEP, FRC increased to 22.3 ± 5.9 ml/kg (P = 0.4829, compared with baseline) in infants and 28.2 ± 5.8 ml/kg (P < 0.001) in children. The lung clearance index increased after neuromuscular blockade, whereas baseline values were regained after the application of PEEP. The changes induced by neuromuscular blockade were significantly greater in infants compared with preschool children (P < 0.001). Conclusions: Although the use of neuromuscular blockade decreased FRC and ventilation distribution substantially in both groups, the changes were more pronounced in young infants. With PEEP, FRC increased and ventilation homogeneity was restored. These results provide a rationale to use PEEP in anesthetized, paralyzed infants and children.

Measurement of functional residual capacity in rabbits and children using an ultrasonic flow meter.

A sulfur hexafluoride (SF6) washin/washout technique was developed using an ultrasonic flowmeter to measure functional residual capacity (FRC) during mechanical ventilation. The ultrasonic flowmeter measures simultaneously flow and molar mass of the mainstream gas. Ventilation distribution was studied using moment ratios analysis (alveolar-based mean dilution number). Accuracy and precision of the measurement technique were tested in a mechanical lung model, and the methods sensitivity to changes of FRC was assessed in seven ventilated rabbits and six children. In the mechanical lung model with a volume range from 10 to 60 mL, the mean error of FRC measurement was 0.096 ± 0.9 mL (range, 0–2 mL). In seven rabbits (mean body weight, 3.6 kg), measurements of FRC and alveolar-based mean dilution number were made at positive end-expiratory pressures (PEEP) of 0, 3, and 6 cm H2O. The mean coefficient of variation of 66 FRC-measurements was 5.5% (range, 0–15.3%). As the applied PEEP increased, mean FRC per kilogram body weight increased from 13.3 ± 3.4 mL/kg (PEEP of 0 cm H2O) to 16.7 ± 3.6 mL/kg (PEEP of 3 cm H2O) and to 20.8 ± 4.3 mL/kg (PEEP of 6 cm H2O). Alveolar-based mean dilution number decreased accordingly from 1.94 ± 0.42 (PEEP = 0; mean ± SD), to 1.91 ± 0.45 (PEEP = 3) and to 1.59 ± 0.35 (PEEP = 6). In the six children, as applied PEEP increased, mean FRC per kilogram increased from 21.1 ± 4.51 mL/kg (PEEP = 0), to 22.4 ± 1.8 mL/kg (PEEP = 5) and 27.2 ± 3.4 mL/kg (PEEP = 10). FRC measurement using the ultrasonic flowmeter is accurate and simple to use in ventilated and spontaneously breathing children.