Can Pediatricians Assess Exercise-Induced Bronchoconstriction From Post-exercise Videos?

Objective: Exercise-induced bronchoconstriction (EIB) is a highly prevalent morbidity of childhood asthma and defined by a transient narrowing of the airways during or after physical exercise. An exercise challenge test (ECT) is the reference standard for the diagnosis of EIB. Video evaluation of EIB symptoms could be a practical alternative for the assessment of EIB. We studied the ability of pediatricians to assess EIB from post-exercise videos. Methods: A clinical assessment was performed in 20 asthmatic children (mean age 11.6 years) and EIB was measured with a standardized ECT performed in cold, dry air. EIB was defined as a fall in forced expiratory volume in 1 s (FEV1) of ≥10% post-exercise. Children were filmed before and after exercise in frontal position and bare chested. The clinical assessment results and videos were shown to 20 pediatricians (mean experience 14.4 years). Each assessed EIB severity in 5 random children providing 100 assessments, scored on a continuous rating scale (0-10) and in severity classifications (no, mild, moderate, severe) using a scoring list including physical asthma symptoms. Correlations between predicted scores and objective scores were calculated with Spearman's rho and Cohen's Kappa. A generalized linear model was used to assess the relationship between physical symptoms and fall in FEV1. Results: Median fall in FEV1 after exercise was 15.1% (IQR 1.2-65.1). Pediatricians detected EIB with a sensitivity of 78% (95% CI 66-87%) and a specificity of 40% (95% CI 27-55%). The positive predictive value for a pediatricians' diagnosis of EIB was 61% (95% CI 50-72%). The negative predictive value was 60% (95% CI 42-76%). The agreement between predicted EIB severity classifications and the validated classifications based on the ECT's, was fair [Kappa = 0.36 (95% CI 0.23-0.48)]. The correlation between predicted EIB severity scored on a continuous rating scale and fall in FEV1 after exercise was weak (rs = 0.39, p < 0.001). Independent predictive variables for fall in FEV1 were wheezing (-11%), supraclavicular retractions (-8.4%) and a prolonged expiratory phase (-8.8%). Conclusion: The ability of pediatricians to assess EIB from post-exercise videos is fair at best, implicating that standardized ECT's are still vital in the assessment of EIB.

The Mozart study: a relation between dynamic hyperinflation and physical activity in patients with chronic obstructive pulmonary disease?

BACKGROUND: Many patients with chronic obstructive pulmonary disease (COPD) experience dyspnoea during exercise, resulting in a reduction of physical activity (PA). Dynamic hyperinflation (DH) is seen as a major cause of dyspnoea in COPD. OBJECTIVE: The objective of the current study was to investigate the relationship between DH, in terms of the amount of DH and the development and recovery rate of DH in patients with COPD, and PA. METHODS: Thirty-five patients with stable COPD were included from an outpatient clinic (14 GOLD II and 21 GOLD III, median age 65). PA was assessed using an accelerometer. Subjects underwent metronome-paced tachypnoea (MPT) to induce DH. To quantify the amount of DH during MPT, a decrease in inspiratory capacity (IC) or a change in IC as percentage of total lung capacity was used. RESULTS: No significant correlations were found between the parameters describing DH and PA. Secondary correlation analyses showed a negative correlation between static hyperinflation (SH) and PA (r = -0·39; P = 0·02). The pattern of breathing during MPT and the test itself showed high interpatient variability. CONCLUSIONS: The absence of a significant correlation between DH and PA is contrary to previous studies. SH did show a correlation with PA. The variety in results and the technical difficulties in execution of the measurements ask for a new, more reliable, method to detect DH and investigate its relation with PA in patients with COPD.

Safety and Tolerability of Nebulized Amoxicillin-Clavulanic Acid in Patients with COPD (STONAC 1 and STONAC 2).

The safety and tolerability of nebulized amoxicillin clavulanic acid were determined in patients with stable COPD and during severe exacerbations of COPD. Nine stable COPD patients received doses ranging from 50:10 mg up to 300:60 mg amoxicillin clavulanic acid and eight patients hospitalised for a COPD exacerbation received fixed doses 200/40 mg twice daily. Safety was evaluated by spirometry before and after inhalation. Tolerability was evaluated by questionnaire. Plasma and expectorated sputum samples were assayed for amoxicillin content. Seventeen patients underwent in total 100 nebulizations with amoxicillin clavulanic acid. In this safety and tolerability study no clinically relevant deteriorations in FEV1 were observed. Nebulized amoxicillin clavulanic acid produces sputum concentrations well above the Minimal Inhibiting Concentration of 90% for potential pathogenic micro-organisms, with low concentrations in the central compartment (low systemic exposure). Based on spirometry and reported side effects, inhalation of nebulized amoxicillin clavulanic acid seems to be safe and well tolerated, both in stable patients with COPD as in those experiencing a severe exacerbation. Levels of amoxicillin were adequate.

An external validation of the ETVSS for both short-term and long-term predictive adequacy in 104 pediatric patients.

PURPOSE: This study aims to provide external validation of the "Endoscopic Third Ventriculostomy Success Score (ETVSS)" for both short-term and long-term predictive adequacy. METHODS: Between 1998 and 2007, we collected clinical follow-up data (after 6 and 36 months) of all 104 hydrocephalic children (<18 years of age) treated by endoscopic third ventriculostomy (ETV) in our hospital. Predictive adequacy of ETVSS for 6- and 36-month periods was tested by means of an unpaired t test, Hosmer-Lemeshow "goodness-of- fit" test, and area under the receiver operating characteristic curve. RESULTS: Mean follow-up was 73.4 months. For both the short-term (6 months) and the long-term (36 months) periods, the mean predicted probability of ETV for the patients with successful ETV treatment was significantly higher than in the patients with failed ETV treatment. The areas under the curve for the short- and long-term periods were, respectively, 0.82 (95% CI 0.71-0.92) and 0.73 (95% CI 0.62-0.84). For patients with moderate ETVSS (50-70), the median age at first ETV was significantly higher for patients with successful ETV for both short- and long-term periods. CONCLUSION: In hydrocephalic children, the ETVSS is a useful tool for prediction of outcome after ETV treatment. The ETVSS is more adequate in predicting short-term than long-term success. In our population, it is suggested that success rate for patients with moderate ETVSS could be improved if more weight is attributed to age at first ETV.

Impact on clinical decision making of quality control standards applied to sputum analysis in COPD.

PURPOSE: Sputum analysis is important in COPD exacerbation management. We determined whether application of stringent quality control criteria for sputum samples had an impact on culture results. METHODS: We analyzed sputum samples of 108 patients during stable COPD and during exacerbations. To all samples quality control standards and culture interpretation rules according to the American Society of Microbiologists (ASM) were applied. RESULTS: In sputum exacerbation samples considered appropriate according to ASM quality standards, criteria for infection (40%) were met more often compared to inappropriate samples (13%) (p < 0.001). The same pattern was observed when applying these rules to sputum samples obtained during stable disease, (50% vs. 18%, p < 0.001). There was no difference in the percentage of infectious cultures obtained during the stable state and exacerbations. CONCLUSIONS: Applying stringent quality control criteria to sputum samples can have a profound effect on the labeling of sputum samples as infectious, and therefore on clinical decision making.

Relation of sputum colour to bacterial load in acute exacerbations of COPD.

BACKGROUND: When COPD patients present with an exacerbation, one cannot verify a bacterial cause of an exacerbation without time-consuming laboratory analyses. This makes it difficult to decide up front if antibiotic treatment is needed. Therefore, in clinical practice sputum colour and purulence are often used. OBJECTIVE: To determine whether sputum colour and purulence, assessed by the Stockley colour chart, correlated with overall bacterial load in COPD patients admitted for an exacerbation. To check the robustness of the colour and purulence assessment, we correlated the changes in these parameters and the corresponding change in bacterial load in sputum over the first seven days of hospitalisation. METHODS: Twenty-two COPD patients admitted to the hospital for an exacerbation were included. During the first seven days daily sputum samples were collected. RESULTS: A very weak association between bacterial load and sputum colour was found. There was no difference in bacterial load between patients with purulent sputum or not. Also, no consistent relationship between change in sputum colour and change in bacterial load during admission was found. CONCLUSIONS: The very weak association between bacterial load and sputum colour confirms concerns over the usefulness of the colour chart. The distinction between purulent and mucoid sputum at exacerbation is insufficient for distinction between patients who are likely to benefit from antibiotic therapy and those who are not. Complementary studies are needed to determine which other, easily measurable factors can be used as predictors for an indication for use of antibiotics; sputum colour is not the one.