Correlation of anthropometric index and cardiopulmonary exercise testing in children with pectus excavatum.

BACKGROUND: Cardiopulmonary exercise testing (CPET) is a method used to evaluate functional impairment of patients with various diseases. OBJECTIVE: The objective was to use CPET to estimate the usability of anthropometric index (AI) in patients with pectus excavatum (PE) as a marker of functional impairment caused by chest deformity. METHODS: The study included 32 paediatric patients (28 males) with PE. Patients underwent CPET using a breath-by-breath exhaled gas analysis method and continuous monitoring of cardiac parameters. RESULTS: In both groups, two (overall four) patients met criteria for cardiogenic limitation (low VO2 and low O2Pulse). Mean VO2/WR was below two standard deviations (2SD) in patients with less severe PE; other observed parameters were within normal limits (Z-score ± 2 SD). The AI had no observed correlation with peak ventilation, VO2peak and peak workload. CONCLUSION: The obtained CPET data do not correlate well with the severity of chest deformity expressed with AI. There were similar physical activity limitations in both examined groups of patients and they did not depend on the severity of the deformity.

Relationship between cough reflex sensitivity and body mass index in children with chronic cough - a pilot study.

Obesity is characterized by chronic, low-grade systemic inflammation. Obesity may also be associated with chronic cough. The aim of this pilot study was to clarify relation of cough reflex sensitivity and body mass index (BMI) in children with chronic cough. Altogether 41 children having symptoms of chronic cough were submitted to cough reflex sensitivity measurement. We assessed the relation of cough reflex sensitivity (CKR) due to BMI. Cough reflex sensitivity was defined as the lowest capsaicin concentration which evoked two (C2) or five (C5) coughs. Capsaicin aerosol in doubling concentrations (from 0.61 to 1250 micromol/l) was inhaled by a single breath method (KoKo DigiDoser; nSpire heath Inc, Louisville, CO, USA), modified by the addition of an inspiratory flow regulator valve (RIFR; nSpire heath Inc, Louisville, CO, USA). BMI was calculated. Pulmonary function was within normal range. Concentrations of capsaicin causing two (C2) and five coughs (C5) were reported. Children (22 boys and 19 girls, mean age 6.8 years) cough reflex sensitivity (median, with the Inter-Quartile Range) for C2 was 19.5 (73.4) micromol/l; for C5 it was 78.1 (605.5) micromol/l. We have noticed statistically significant relation of the cough reflex sensitivity (C5) and body mass index (P<0.0001); however, the effect size was small, R2=0.03. Increase of body mass index in one unit is associated with -34.959 micromol/l decrease of C5. We did not find a statistically significant relation between C2 and BMI (P=0.41). The median value of CKR (C2) in boys is not statistically significantly different than the median value of CKR (C2) in girls (P-value 0.5). The median value of CKR (C5) in boys is not statistically significantly different than the median value of CKR (C5) in girls (P-value 0.5). Increase of body mass index in children suffering from chronic cough relates to decrease of cough reflex sensitivity (C5 value).

The effect of adenoidectomy on cough reflex sensitivity in atopic children.

The aim of this study was to determine whether cough sensitivity is changed after adenoidectomy in atopic children with chronic cough. 21 Children having symptoms of chronic cough and adenoid hypertrophy verified by nasal fiberoptic endoscopy were submitted to cough sensitivity measurement before and after adenoidectomy. Their pulmonary function was within normal range. Concentrations of capsaicin causing two (C2) and five coughs (C5) were reported. Children' (14 boys and 7 girls, mean age 6,52 yrs) cough sensitivity (geometric mean, with 95% CI) for C2 was preoperatively (before adenoidectomy) 19.95 (9.95-39.98) micromol/l vs. children' C2 postoperatively 14.04 (7.16-27.55) (P = .083 for Wilcoxon paired two sample test). Children' C5 was preoperatively 86.26 (39.25-189.57) micromol/l vs. C5 postoperatively 95.23 (46.33-195.75) micromol/l (P = .794 for Wilcoxon paired two sample test). We conclude that cough sensitivity for C2 and C5 was not significantly changed after adenoidectomy in atopic children with chronic cough.

The Role of Ion Channels to Regulate Airway Ciliary Beat Frequency During Allergic Inflammation.

Overproduction of mucus is a hallmark of asthma. The aim of this study was to identify potentially effective therapies for removing excess mucus. The role of voltage-gated (Kir 6.1, KCa 1.1) and store-operated ion channels (SOC, CRAC) in respiratory cilia, relating to the tracheal ciliary beat frequency (CBF), was compared under the physiological and allergic airway conditions. Ex vivo experiments were designed to test the local effects of Kir 6.1, KCa 1.1 and CRAC ion channel modulators in a concentration-dependent manner on the CBF. Cilia, obtained with the brushing method, were monitored by a high-speed video camera and analyzed with ciliary analysis software. In natural conditions, a Kir 6.1 opener accelerated CBF, while CRAC blocker slowed it in a concentration-dependent manner. In allergic inflammation, the effect of Kir 6.1 opener was insignificant, with a tendency to decrease CBF. A cilio-inhibitory effect of a CRAC blocker, while gently reduced by allergic inflammation, remained significant. A KCa 1.1 opener turned out to significantly enhance the CBF under the allergic OVA-sensitized conditions. We conclude that optimally attuned concentration of KCa 1.1 openers or special types of bimodal SOC channel blockers, potentially given by inhalation, might benefit asthma.

N-acetylcysteine effectively diminished meconium-induced oxidative stress in adult rabbits.

Since inflammation and oxidative stress are fundamental in the pathophysiology of neonatal meconium aspiration syndrome (MAS), various anti-inflammatory drugs have been used in experimental and clinical studies on MAS. This pilot study evaluated therapeutic potential of N-acetylcysteine in modulation of meconium-induced inflammation and oxidative lung injury. Oxygen-ventilated adult rabbits were intratracheally given 4 ml/kg of meconium (25 mg/ml) or saline (Sal, n = 6). Thirty minutes later, meconium-instilled animals were treated with intravenous N-acetylcysteine (10 mg/kg, Mec + NAC, n=6) or were non-treated (Mec, n = 6). All animals were oxygen-ventilated for additional 5 hours. Total and differential blood leukocyte counts were determined at baseline, and at 1, 3 and 5 h of the treatment. After sacrificing animals, left lung was saline-lavaged and total and differential cell counts in the bronchoalveolar lavage fluid were determined. Right lung was used for biochemical analyses and for estimation of wet-dry weight ratio. In lung tissue homogenate, thiobarbituric acid-reactive substances (TBARS), dityrosine, lysine-lipid peroxidation (LPO) products, and total antioxidant status (TAS) were detected. In isolated lung mitochondria, TBARS, dityrosine, lysine-LPO products, thiol group content, conjugated dienes, and activity of cytochrome c oxidase were estimated. To evaluate systemic effects of meconium instillation and NAC treatment, TBARS and TAS were determined also in plasma. To evaluate participation of eosinophils in the meconium-induced inflammation, eosinophil cationic protein (ECP) was detected in plasma and lung homogenate. Meconium instillation increased oxidation markers and ECP in the lung and decreased TAS (all P<0.05). NAC treatment reduced ECP and oxidation markers (all P<0.05, except of dityrosine in homogenate and conjugated dienes in mitochondria) and prevented a decrease in TAS (P<0.01) in lung homogenate compared to Mec group. In plasma, NAC decreased TBARS (P<0.001) and ECP, and increased TAS (both P<0.05) compared to Mec group. Concluding, N-acetylcysteine diminished meconium-induced inflammation and oxidative lung injury.

Cough reflex sensitivity in adolescents with diabetic autonomic neuropathy.

OBJECTIVE: Diabetic autonomic neuropathy (DAN) is one of the chronic complications of diabetes mellitus which can involve one or more organ systems. DAN without apparent symptoms is more often in childhood and adolescence. While heart rate variability (HRV) and Ewing's battery of cardiovascular tests are regarded as a gold standard for the diagnosis of DAN, the examination of cough reflex sensitivity (CRS) is another possibility. The aim of this study was to compare HRV and CRS in children with diabetes mellitus. MATERIAL AND METHODS: Sixty one patients (37 girls, 24 boys) aged 15-19 suffering from diabetes mellitus type 1 completed the study. Based on HRV, patients were divided into 2 groups - with DAN (n=25) and without DAN (n=32), 4 patients were excluded because of ambiguous results. CRS was studied in each patient by inhalation of gradually increasing concentration of capsaicin. RESULTS: Subjects with DAN required a significantly higher concentration of capsaicin needed to evoke 2 coughs (median 625 micromol/l, IQR 68.4-625.0 micromol/l vs. median 29.3 micromol/l, IQR 9.8-156.3 micromol/l, P<0.001) and 5 coughs (median 2500.0 micromol/l, IQR 1250.0-2500.0 micromol/l vs. median 312.5 micromol/l, IQR 117.2-625.0 micromol/l, P<0.001) compared with those without DAN. Moreover, a strong negative correlation between HRV and CRS was established. CONCLUSION: Diabetes mellitus lowers the cough response. Cough reflex sensitivity appears to be another sensitive method for the evaluation of DAN in diabetes.

Cardiac autonomic control in adolescents with primary hypertension.

BACKGROUND: Impairment in cardiovascular autonomic regulation participates in the onset and maintenance of primary hypertension. OBJECTIVE: The aim of the present study was to evaluate cardiac autonomic control using long-term heart rate variability (HRV) analysis in adolescents with primary hypertension. SUBJECTS AND METHODS: Twenty two adolescent patients with primary hypertension (5 girls/17 boys) aged 14-19 years and 22 healthy subjects matched for age and gender were enrolled. Two periods from 24-hour ECG recording were evaluated by HRV analysis: awake state and sleep. HRV analysis included spectral power in low frequency band (LF), in high frequency band (HF), and LF/HF ratio. - RESULTS: In awake state, adolescents with primary hypertension had lower HF and higher LF and LF/HF ratio. During sleep, HF was lower and LF/HF ratio was higher in patients with primary hypertension. CONCLUSIONS: A combination of sympathetic predominance and reduced vagal activity might represent a potential link between psychosocial factors and primary hypertension, associated with increased cardiovascular morbidity.

Exhaled carbon monoxide as a new marker of respiratory diseases in children.

Among modern methods included in diagnostic algorithms for various diseases, analyses of expired breath and its condensate acquire increasing importance. Various markers can be determined in the exhaled air, especially volatile gaseous compounds: nitrogen oxide (NO), carbon monoxide (CO), hydrocarbons and 8-isoprostanes. In contrast to NO, CO can serve as a marker of inflammation and oxidation stress. The representation of CO in the exhaled breath (eCO) changes in various diseases of the respiratory and other systems. Among the respiratory diseases in which the use of eCO measurement seems to be perspective and beneficial are bronchial asthma, airways infections, cystic fibrosis, and primary ciliary dyskinesia. The observation of eCO concentrations represents a modern, simple, available, and well reproducible method for the diagnosis of many diseases of respiratory system in children and for the observation of progression, severity of the disease, and response to therapy.

Therapeutic approach to a child with acute respiratory distress syndrome: a report of two cases.

The course of a respiratory disorder in a child may end up in respiratory failure. There are also acute non-respiratory diseases which have a great influence on the respiratory functions and often lead to the acute lung injury and sometimes to the acute respiratory distress syndrome (ARDS). A feature of respiratory function deterioration is changed in the surfactant system. We often see inhibition of its synthesis or damage to its structure. Therapy of children suffering from ARDS should be complex and rapid. Despite many recently published studies explaining the principle of this disorder, the mortality of ARDS is still very high (30-50%). There are several studies documenting successful administration of exogenous surfactant as part of a complex combined therapy of patients with ARDS, which leads to decreased mortality, improved oxygenation, and decreased need for aggressive artificial pulmonary ventilation. The authors of this article present their own experience with administration of exogenous surfactant in therapy of children with ARDS.

Combination of budesonide and aminophylline diminished acute lung injury in animal model of meconium aspiration syndrome.

Combination of low-dose budesonide and low-dose aminophylline may improve lung function in reduced adverse effects compared with high-dose monotherapy. Adult rabbits intratracheally received 4 ml/kg of saline or meconium (25 mg/ml). Meconium-injured rabbits were treated at 0.5 and 2.5 h after meconium instillation by intravenous aminophylline (1.0 mg/kg), by intratracheal budesonide (0.125 mg/kg) followed by intravenous aminophylline (1.0 mg/kg), or were untreated. Although aminophylline improved some respiratory parameters, budesonide+aminophylline more effectively reduced intrapulmonary shunts and improved gas exchange, without significant cardiovascular effects. Combined treatment reduced lung edema and number of lung neutrophils to a higher extent than aminophylline alone. Both treatments reduced lung peroxidation and in vitro airway reactivity to histamine, with a better effect after aminophylline alone. Combination of budesonide and aminophylline enhanced respiratory parameters more effectively, having fewer side effects than aminophylline alone. However, no additive effect of budesonide was observed on lung peroxidation and in vitro airway reactivity.

Changes of airway obstruction parameters in healthy children caused by mother's smoking during pregnancy.

The present study was aimed at the assessment of the impact of mother smoking during pregnancy on changes of phase angle (phi) and T(me)/T(E) index in healthy children. A hundred and twenty seven children, divided according to age (<6 months and >6 months of age) and mother smoking anamnesis were investigated by noncalibrated respiratory inductive plethysmography in the supine position. We found statistically significant changes of phi (p<0.05) and T(me)/T(E) in healthy children of non-smoking mothers against a group of smoking mother's children of up to 6 months of age. These differences were not confirmed in children older than 6 months. Moreover, in the smoking mother group, we found statistically significant changes (P<0.05) of phi and T(me)/T(E) in children of up to 6 months of age in comparison with children older than 6 month. The results revealed a negative impact of mother smoking during pregnancy represented by changes in airway obstruction parameters, which appeared especially in the group of youngest children.

The influence of autonomic neuropathy on cough reflex sensitivity in children with diabetes mellitus type 1.

Diabetic autonomic neuropathy (DAN) is manifested by dysfunction of one or more organ systems. Its subclinical form (sDAN) can be recognized with the use of noninvasive cardiovascular reflex tests. As the cough reflex is mediated via autonomic nervous system, there is a reason to suppose that it can also be changed due to presence of sDAN. The aim of the present study was to assess cough reflex sensitivity (CRS) in diabetic children with and without sDAN. A CRS test was performed in 35 children suffering from diabetes mellitus type 1 and the results were compared with those from age-matched 27 healthy children. Cough was induced by inhalation of capsaicin aerosol in doubling concentrations (0.61-1250 micromol/l) for 400 ms each. CRS was defined as the lowest capsaicin concentration that evoked 2 or more coughs (C2 parameter) and 5 or more coughs (C5 parameter). We found that CRS in the whole group of diabetic children was not significantly different from that in healthy children [diabetic children--C2: 75.1 micromol/l (95% CI: 42.0-134.2 micromol/l)] vs. healthy children--C2: 72.4 micromol/l (95% CI: 75.7-644.8 micromol/l)]. However, a significant decrease (P=0.005) in CRS was found in diabetic children with sDAN [n=12; C2: 221.0 micromol/l (95% CI: 75.7-644.8 micromol/l)] compared with diabetic children without sDAN [(n=23; C2: 42.7 micromol/l (95% CI: 23.1-79.0 micromol/l)]. We conclude that testing cough reflex sensitivity might be a way to establish the presence of diabetic neuropathy.