Diagnosis and management of asthma in children

Asthma is the the most common chronic respiratory condition of childhood worldwide, with around 14% of children and young people affected. Despite the high prevalence, paediatric asthma outcomes are inadequate, and there are several avoidable deaths each year. Characteristic asthma features include wheeze, shortness of breath and cough, which are typically triggered by a number of possible stimuli. There are several diagnostic challenges, and as a result, both overdiagnosis and underdiagnosis of paediatric asthma remain problematic.Effective asthma management involves a holistic approach addressing both pharmacological and non-pharmacological management, as well as education and self-management aspects. Working in partnership with children and families is key in promoting good outcomes. Education on how to take treatment effectively, trigger avoidance, modifiable risk factors and actions to take during acute attacks via personalised asthma action plans is essential.This review aimed to provide an overview of good clinical practice in the diagnosis and management of paediatric asthma. We discuss the current diagnostic challenges and predictors of life-threatening attacks. Additionally, we outline the similarities and differences in global paediatric asthma guidelines and highlight potential future developments in care. It is hoped that this review will be useful for healthcare providers working in a range of child health settings.

Data-driven recognition memory: a new technique and some data on age differences

In this study, we investigate the effect on recognition memory of having target and distractor stimuli consisting of different combinations of low-level elements (letters), relative to when targets and distractors consist of combinations of the same elements (nonoverlap and overlap conditions, respectively). It was found that recognition memory was enhanced in the nonoverlap condition, even though subjects reported being unaware of this experimental manipulation. This confirms the importance of perceptually driven processing in the implicit memory component of recognition memory. The extent to which this effect occurs is found to be age dependent, with elderly subjects benefiting more from having targets and distractors consisting of nonoverlapping elements. This is consistent with the notion that elderly subjects show less reliance on item-specific/contextual detail to support recognition memory.

Comparison of new generation motion-resistant pulse oximeters

AIM

To compare the performance of pulse oximeters during movement and brachial artery occlusion.

METHODS

Three machines (MasimoSET, using MasimoSET LNOP Pdt paediatric sensor, Mars 2001 using Novametrix paediatric sensor no. 6455 and Nellcor 595 using Nellcor 595 Oximax-P paediatric sensor and Nellcor 595 MAX-FAST adhesive forehead reflectance sensor) were used simultaneously on the left hand and forehead. The subjects were 18 healthy children aged 6-10 years. Interventions were 20 sequential 90 degrees body turns from mimicking normal movements while asleep followed by step increases in brachial artery occlusion. Mean heart rate (HR) from the four machines was compared with ECG HR. Haemoglobin O(2) saturation was compared with a baseline saturation and the proportion of epochs with false (low) saturation values.

RESULTS

The mean difference from ECG HR was not clinically significantly different for any machine but the limits of agreement were such that the Mars Model 2001 and Nellcor 595 (forehead) could have clinically important differences from ECG-derived HR (-20.04-15.00 and -14.95-14.04, respectively). Only the Nellcor 595 with finger probe had limits of agreement within the a priori set value of 4%. The prevalence of epochs with an haemoglobin O2 saturation of greater than 4% below baseline values was lowest for the Nellcor 595 finger probe (1.59%) and highest for the Nellcor forehead probe (20.45%). During brachial artery occlusion, all machines performed well up to within 20 mmHg of total occlusion.

CONCLUSION

Current motion-resistant pulse oximeters performed well but only the Nellcor 595 with finger probe achieved our a priori set standards.

Clinical and molecular characterization of the R751L-CFTR mutation

Cystic fibrosis (CF) arises from mutations in the CF transmembrane conductance regulator (CFTR) gene, resulting in progressive and life-limiting respiratory disease. R751L is a rare CFTR mutation that is poorly characterized. Our aims were to describe the clinical and molecular phenotypes associated with R751L. Relevant clinical data were collected from three heterozygote individuals harboring R751L (2 patients with G551D/R751L and 1 with F508del/R751L). Assessment of R751L-CFTR function was made in primary human bronchial epithelial cultures (HBEs) and Xenopus oocytes. Molecular properties of R751L-CFTR were investigated in the presence of known CFTR modulators. Although sweat chloride was elevated in all three patients, the clinical phenotype associated with R751L was mild. Chloride secretion in F508del/R751L HBEs was reduced compared with non-CF HBEs and associated with a reduction in sodium absorption by the epithelial sodium channel (ENaC). However, R751L-CFTR function in Xenopus oocytes, together with folding and cell surface transport of R751L-CFTR, was not different from wild-type CFTR. Overall, R751L-CFTR was associated with reduced sodium chloride absorption but had functional properties similar to wild-type CFTR. This is the first report of R751L-CFTR that combines clinical phenotype with characterization of functional and biological properties of the mutant channel. Our work will build upon existing knowledge of mutations within this region of CFTR and, importantly, inform approaches for clinical management. Elevated sweat chloride and reduced chloride secretion in HBEs may be due to alternative non-CFTR factors, which require further investigation.