Efficacy of a loading dose of IV salbutamol in children with severe acute asthma admitted to a PICU: a randomized controlled trial.

The optimal dose regimen for intravenous (IV) treatment in children with severe acute asthma (SAA) is still a matter of debate. We assessed the efficacy of adding a salbutamol loading dose to continuous infusion with salbutamol in children admitted to a pediatric intensive care unit (PICU) with SAA. This multicentre, placebo-controlled randomized trial in the PICUs of four tertiary care children's hospitals included children (2-18 years) with SAA admitted between 2017 and 2019. Children were randomized to receive either a loading dose IV salbutamol (15 mcg/kg, max. 750 mcg) or normal saline while on continuous salbutamol infusion. The primary outcome was the asthma score (Qureshi) 1 h after the intervention. Analysis of covariance models was used to evaluate sensitivity to change in asthma scores. Serum concentrations of salbutamol were obtained. Fifty-eight children were included (29 in the intervention group). Median baseline asthma score was 12 (IQR 10-13) in the intervention group and 11 (9-12) in the control group (p = 0.032). The asthma score 1 h after the intervention did not differ significantly between the groups (p = 0.508, ß-coefficient = 0.283). The median increase in salbutamol plasma levels 10 min after the intervention was 13 µg/L (IQR 5-24) in the intervention group and 4 µg/L (IQR 0-7) in the control group (p = 0.001). Side effects were comparable between both groups. CONCLUSION: We found no clinical benefit of adding a loading dose IV salbutamol to continuous infusion of salbutamol, in children admitted to the PICU with SAA. Clinically significant side effects from the loading dose were not encountered. WHAT IS KNOWN: • Pediatric asthma guidelines struggle with an evidence-based approach for the treatment of SAA beyond the initial steps of oxygen suppletion, repetitive administration of inhaled ß2-agonists, and systemic steroids. • During an SAA episode, effective delivery of inhaled drugs is unpredictable due to severe airway obstruction. WHAT IS NEW: • This study found no beneficial effect of an additional loading dose IV salbutamol in children admitted to the PICU. • This study found no clinically significant side effects from the loading dose.

Risk factors for intensive care admission in children with severe acute asthma in the Netherlands: a prospective multicentre study.

RATIONALE: Severe acute asthma (SAA) can be fatal, but is often preventable. We previously observed in a retrospective cohort study, a three-fold increase in SAA paediatric intensive care (PICU) admissions between 2003 and 2013 in the Netherlands, with a significant increase during those years of numbers of children without treatment of inhaled corticosteroids (ICS). OBJECTIVES: To determine whether steroid-naïve children are at higher risk of PICU admission among those hospitalised for SAA. Furthermore, we included the secondary risk factors tobacco smoke exposure, allergic sensitisation, previous admissions and viral infections. METHODS: A prospective, nationwide multicentre study of children with SAA (2-18 years) admitted to all Dutch PICUs and four general wards between 2016 and 2018. Potential risk factors for PICU admission were assessed using logistic regression analyses. MEASUREMENTS AND MAIN RESULTS: 110 PICU and 111 general ward patients were included. The proportion of steroid-naïve children did not differ significantly between PICU and ward patients. PICU children were significantly older and more exposed to tobacco smoke, with symptoms >1 week prior to admission. Viral susceptibility was not a significant risk factor for PICU admission. CONCLUSIONS: Children with SAA admitted to a PICU were comparable to those admitted to a general ward with respect to ICS treatment prior to admission. Preventable risk factors for PICU admission were >7 days of symptoms without adjustment of therapy and exposure to tobacco smoke. Physicians who treat children with asthma must be aware of these risk factors.

Children with severe acute asthma admitted to Dutch PICUs: A changing landscape.

The number of children requiring pediatric intensive care unit (PICU) admission for severe acute asthma (SAA) around the world has increased. OBJECTIVES: We investigated whether this trend in SAA PICU admissions is present in the Netherlands. METHODS: A multicenter retrospective cohort study across all tertiary care PICUs in the Netherlands. Inclusion criteria were children (2-18 years) hospitalized for SAA between 2003 and 2013. Data included demographic data, asthma diagnosis, treatment, and mortality. RESULTS: In the 11-year study period 590 children (660 admissions) were admitted to a PICU with a threefold increase in the number of admissions per year over time. The severity of SAA seemed unchanged, based on the first blood gas, length of stay and mortality rate (0.6%). More children received highflow nasal cannula (P < 0.001) and fewer children needed invasive ventilation (P < 0.001). In 58% of the patients the maximal intravenous (IV) salbutamol infusion rate during PICU admission was 1 mcg/kg/min. However, the number of patients treated with IV salbutamol in the referring hospitals increased significantly over time (P = 0.005). The proportion of steroid-naïve patients increased from 35% to 54% (P = 0.004), with a significant increase in both age groups (2-4 years [P = 0.026] and 5-17 years [P = 0.036]). CONCLUSIONS: The number of children requiring PICU admission for SAA in the Netherlands has increased. We speculate that this threefold increase is explained by an increasing number of steroid-naïve children, in conjunction with a lowered threshold for PICU admission, possibly caused by earlier use of salbutamol IV in the referring hospitals.

Impact of the tumor microenvironment on prognosis in follicular lymphoma is dependent on specific treatment protocols.

BACKGROUND: The clinical behavior of follicular lymphoma is largely determined by properties of the non-malignant tumor microenvironment. The precise nature of the cell populations is still unclear and published data on their prognostic significance are highly conflicting. This may be partly due to heterogeneous composition and treatments. DESIGN AND METHODS: Pre-treatment biopsy samples of patients with follicular lymphoma treated in an EORTC/BNLI trial comparing fludarabine to cyclophosphamide, vincristine and prednisone (CVP) chemotherapy could be retrieved for 61 patients in five European countries. Immunohistochemical investigations were performed evaluate tumor cell characteristics, T-cell subsets, follicular dendritic cells and macrophages and associations with clinical outcome were studied. RESULTS: Some markers showed a homogeneous prognostic impact, while others had a different nd sometimes opposite effect in the treatment arms. CD69 expression on tumor cells was a poor prognostic sign and an interfollicular infiltrate of FoxP3-positive T cells was a good prognostic sign irrespective of the treatment arm. It is suggestive that a dense infiltrate of FoxP3-positive T cells, dense and interfollicular infiltrate of CD68-positive macrophages and complete follicular dendritic meshworks were associated with a favorable time to progression in CVP-treated patients, while being poor prognostic sign in fludarabine-treated patients. CONCLUSIONS: Our results suggest that characteristic properties of the microenvironment in follicular lymphoma determines the responses to essentially different chemotherapeutic approaches. These data may provide an explanation for the highly conflicting results on immunohistochemical markers and the prognostic role of the microenvironment in follicular lymphoma reported thus far and lay the basis for the development of predictive assays to tailor treatment in patients with follicular lymphoma.