|
| ||
|
|
||
Breathing Parameters (breathing + parameter)
Selected AbstractsThe murine neurokinin NK1 receptor gene contributes to the adult hypoxic facilitation of ventilationEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 12 2002Krzysztof Ptak Abstract Substance P and neurokinin-1 receptors (NK1) modulate the respiratory activity and are expressed early during development. We tested the hypothesis that NK1 receptors are involved in prenatal development of the respiratory network by comparing the resting respiratory activity and the respiratory response to hypoxia of control mice and mutant mice lacking the NK1 receptor (NK1,/,). In vitro and in vivo experiments were conducted on neonatal, young and adult mice from wild-type and NK1,/, strains. In the wild strain, immunohistological, pharmacological and electrophysiological studies showed that NK1 receptors were expressed within medullary respiratory areas prior to birth and that their activation at birth modulated central respiratory activity and the membrane properties of phrenic motoneurons. Both the membrane properties of phrenic motoneurons and the respiratory activity generated in vitro by brainstem-spinal cord preparation from NK1,/, neonate mice were similar to that from the wild strain. In addition, in vivo ventilation recordings by plethysmography did not reveal interstrain differences in resting breathing parameters. The facilitation of ventilation by short-lasting hypoxia was similar in wild and NK1,/, neonates but was significantly weaker in adult NK1,/, mice. Results demonstrate that NK1 receptors do appear to be necessary for a normal respiratory response to short-lasting hypoxia in the adult. However, NK1 receptors are not obligatory for the prenatal development of the respiratory network, for the production of the rhythm, or for the regulation of breathing by short-lasting hypoxia in neonates. [source] Lung-function tests in neonates and infants with chronic lung disease: Tidal breathing and respiratory controlPEDIATRIC PULMONOLOGY, Issue 5 2006BMedSc, David N. Baldwin MBBS Abstract This paper is the fourth in a series of reviews that will summarize available data and critically discuss the potential role of lung-function testing in infants with acute neonatal respiratory disorders and chronic lung disease of infancy. The current paper addresses information derived from tidal breathing measurements within the framework outlined in the introductory paper of this series, with particular reference to how these measurements inform on control of breathing. Infants with acute and chronic respiratory illness demonstrate differences in tidal breathing and its control that are of clinical consequence and can be measured objectively. The increased incidence of significant apnea in preterm infants and infants with chronic lung disease, together with the reportedly increased risk of sudden unexplained death within the latter group, suggests that control of breathing is affected by both maturation and disease. Clinical observations are supported by formal comparison of tidal breathing parameters and control of breathing indices in the research setting. Pediatr Pulmonol. 2006; 41:391,419. © 2006 Wiley-Liss, Inc. [source] Risk factors of bronchial hyperresponsiveness in children with wheezing-associated respiratory infectionPEDIATRIC PULMONOLOGY, Issue 1 2005Sitthivuddhi Futrakul MD Abstract The objectives of this study were to identify possible risk factors of bronchial hyperesponsiveness (BHR) in children up to 5 years of age with wheezing-associated respiratory infection (WARI), and to study the prevalence of BHR. Children up to 5 years of age with WARI were enrolled in the study. The parents or caregivers of children were asked about their demographic data and clinical histories. Physical examination and clinical score assessment were performed. Pulmonary function tests, i.e., tidal breathing flow volume (TBFV), were performed to measure tidal breathing parameters before and after salbutamol nebulization. If volume at peak tidal expiratory flow/expiratory tidal volume and time to peak expiratory flow/total expiratory time increased ,20%, or tidal expiratory flow at 25% of tidal volume/peak tidal expiratory flow increased ,20% after nebulization therapy, BHR was diagnosed. The number in the positive BHR group was used to calculate the prevalence of BHR, and clinical features were compared with those of the negative BHR group. Categorical data were analyzed for statistical significance (P,<,0.05) by chi-square test or Fisher's exact test, or Student's t -test, as appropriate. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for those with statistical significance. One hundred and six wheezing children underwent pulmonary function tests before and after salbutamol nebulization. With the aforementioned criteria, 41 cases (38.7%) were diagnosed with BHR. History of reactive airway disease, (OR, 6.31; 95% CI, 1.68,25), maternal history of asthma (OR, 3.45; 95% CI, 1.34,9), breastfeeding less than 3 months (OR, 3.18; 95% CI, 1.26,8.12), and passive smoking (OR, 3; 95% CI, 1.15,7.62) were significant risk factors of BHR. The eosinophil count was significantly higher in the BHR (+) group particularly, in children 1,5 years of age (P,,,0.01). Patchy infiltrates were more commonly found in patients with negative BHR but not statistically significant. In conclusion, a history of reactive airway disease, maternal history, breastfeeding less than 3 months, and passive smoking were significant risk factors for BHR. Pediatr Pulmonol. © 2005 Wiley-Liss, Inc. [source] Severe obstructive sleep apnea: Sleepy versus nonsleepy patientsTHE LARYNGOSCOPE, Issue 3 2010Arie Oksenberg PhD Abstract Objectives/Hypothesis: To compare demographic and polysomnographic data of sleepy versus nonsleepy severe obstructive sleep apnea (OSA) patients according to the Epworth Sleepiness Scale (ESS). Study Design: Retrospective cohort. Methods: Six hundred forty-four consecutive severe (apnea-hypopnea index [AHI] , 30) adult OSA patients who underwent a polysomnographic evaluation in our sleep disorders unit. ESS data were available in 569 (88.3%). Three hundred twenty-seven (57.5%) patients had ESS > 10. Results: Sleepy severe OSA patients are slightly younger and more obese than nonsleepy patients. These sleepy patients have shorter sleep latency and lower percentage of slow wave sleep. They consistently show a higher AHI, both supine and lateral AHI, have a higher number of short arousals, and a higher arousal index. They also have higher snoring loudness in the supine and both lateral positions and a lower minimal SaO2 in rapid eye movement and non-rapid eye movement sleep. After adjusting for confounders, a logistic regression model points to apnea index as a significant prognostic factor for excessive daytime sleepiness. Conclusions: Severe OSA sleepy patients have a syndrome that is significantly more severe than nonsleepy patients. Sleepy patients have worse sleep-related breathing parameters, and their sleep patterns are lighter and more fragmented than nonsleepy patients. Apnea index appears as an important prognostic factor for excessive daytime sleepiness. Laryngoscope, 2010 [source] | ||||||||||