AimTo describe the changes to paediatric intensive care unit (PICU) admission patterns and ventilation requirements for children with bronchiolitis following the introduction of humidified high‐flow nasal cannula oxygen outside the PICU.MethodsRetrospective study comparing patients <24 months of age with a discharge diagnosis of bronchiolitis admitted to the PICU. A comparison was made between those before humidified high‐flow nasal cannula oxygen use (year 2008) to those immediately following the introduction of humidified high‐flow nasal cannula oxygen use (year 2011) and those following further consolidation of humidified high‐flow nasal cannula oxygen use outside the PICU (year 2013).ResultsHumidified high‐flow nasal cannula oxygen use up to 1 L/kg/min in the hospital did not reduce PICU admission. Intubation rates were reduced from 22.2% in 2008 to 7.8% in 2013. There was a non‐significant trend towards decreased length of stay in the PICU while hospital length of stay showed a significant decrease following the introduction of humidified high‐flow nasal cannula oxygen. Age <6 months and respiratory syncytial virus bronchiolitis were associated with an increased chance of failing humidified high‐flow nasal cannula oxygen therapy.ConclusionHumidified high‐flow nasal cannula oxygen utilised outside of the PICU in our institution for children with bronchiolitis did not reduce admission rates or length of stay to the PICU but was associated with a decreasing need for invasive ventilation and reduced hospital length of stay.

Aim: To describe the clinical presentation and course of children admitted to the paediatric intensive care unit (PICU) with human metapneumovirus (hMPV) infection, and compare them with children admitted to the PICU with respiratory syncytial virus (RSV) infection.Methods: hMPV was identified by immunofluorescence in 22 children admitted to the PICU over a 16-month period. The medical records of these children were reviewed retrospectively, and their clinical and laboratory data were compared with 66 children admitted to the PICU with positive tests for RSV over the same period.Results: Children admitted to the PICU with hMPV were significantly older than children with RSV (P = 0.003). Children with hMPV presented more commonly with pneumonia or pneumonitis (29% vs. 16%), and less commonly with bronchiolitis (43% vs. 68%) than RSV (P = 0.13). Invasive ventilation was required in 10 patients (48%) with hMPV, and non-invasive ventilation was required in a further 5 (28%), similar to patients with RSV. Children with hMPV were more likely to have an underlying co-morbidity (P = 0.11).Conclusions: Children admitted to the PICU with hMPV have a similar disease presentation and severity as children admitted with RSV, including some with extremely severe disease who require additional ventilatory or cardiovascular support. Children with hMPV are likely to be older than those with RSV, and more likely to present with pneumonia and less likely to present with bronchiolitis.

In studying AQPs in the setting of LCOS, we sought to refine the characterisation of AQP expression in the hearts of mammals. We focused on the species relevant to the planned initial animal models – rats and sheep, with reference to mice and keeping in mind the basic relevance of human expression. We focused on the AQPs that had been previously described in the myocardium – AQP1 and AQP4. Immunohistochemistry, Western blot, semi-quantitative and quantitative RT-PCR were conducted on whole cell preparations and subcellular fractions to define more precisely the expression and localisation of AQPs in the myocardium. Additionally a trial of in vitro ischaemia was undertaken to determine if there was a change in AQP expression with ischaemia in rat myocardium. Ambiguities in expression were resolved through use of AQP knockout mouse tissue. An osmotic equilibrium study using myocardial membrane vesicles was performed to determine the functional contribution of AQPs in mouse myocardium. AQP1, AQP4, AQP7 and AQP11 mRNA were present in myocardium from mouse, rats and humans. Sheep myocardium contained AQP1 and AQP4 as well as AQP0, AQP3 and AQP9. AQP1 protein was expressed in the endothelium of myocardial vessels in rat and sheep. Myocellular expression of AQP1 on immunohistochemistry was supported by expression in rat cardiomyocytes which had negligible endothelial tissue present. AQP4 mRNA was found in rat, sheep, mouse and human heart. AQP4 protein was present in mouse and sheep heart on Western blot, although immunohistochemistry in sheep myocardium revealed non-specific nuclear staining. Western blots of rat myocardium revealed a protein of expected size, although only non-specific staining was present on immunohistochemistry. A trial of in vitro ischaemia, using quantitative RT-PCR demonstrated a six fold increase in AQP4 compared to baseline, but baseline levels of AQP4 were negligible. There was no change in AQP1. Western blot comparison of

OBJECTIVE:To compare clinical assessment of cardiac performance with an invasive method of haemodynamic monitoring.DESIGN AND SETTING:Prospective observational study in a 16-bed tertiary paediatric intensive care unit.PATIENTS AND PARTICIPANTS:Infants and children undergoing cardiopulmonary bypass and surgical repair of congenital heart lesions.INTERVENTIONS:Based on physical examination and routinely available haemodynamic monitoring in the paediatric intensive care unit, medical and nursing staff assessed cardiac index, systemic vascular resistance index and volume status. Clinical assessment was compared with cardiac index, systemic vascular resistance index and global end diastolic volume index, obtained by femoral artery thermodilution.MEASUREMENTS AND RESULTS:A total of 76 clinical estimations of the three parameters were made in 16 infants and children undergoing biventricular repair of congenital heart lesions. Agreement was poor between clinical and invasive methods of determining all three studied parameters of cardiac performance. Cardiac index was significantly underestimated clinically; mean difference was 0.71 l min(-1) m(-2) (95% range of agreement +/-2.7). Clinical estimates of systemic vascular resistance (weighted kappa=0.15) and volume status (weighted kappa=0.04) showed poor levels of agreement with measured values and were overestimated clinically. There was one complication related to a femoral arterial catheter and one device failure.CONCLUSIONS:Routine clinical assessment of parameters of cardiac performance agreed poorly with invasive determinations of these indices. Management decisions based on inaccurate clinical assessments may be detrimental to patients. Invasive haemodynamic monitoring using femoral artery thermodilution warrants cautious further evaluation as there is little agreement with clinical assessment which is presently standard accepted care in this patient population.