ABSTRACT
INTRODUCTION: To take in charge of an asthmatic child it is necessary to evaluate the lung function. METHODS: In this study, the Negative Expiratory Pressure (NEP) has been used for the first time in children with asthma. After lung spirometry by plethysmography, we have used the NEP to assess the prevalence of expiratory flow limitation (FL) during resting breath in 27 asthmatic children (mean age: 11 +/- 2,5 years) 3-4 days after a crisis in both sitting and supine positions. RESULTS: All the children presented an obstructive defect (FEV 1: 63 +/- 13% med) and a dynamic hyperinflation (FRC: 128 +/- 25% med). According to the NEP, 11 children presented an expiratory flow limitation (FL). Asthma was more severe in the FL than in non-FL children (GINA 2002 classification). Among the 11 FL children, 5 were FL in both sitting and supine position and 6 only in supine. Nine of the 27 children were FL with the conventional method. NEP seems a more accurate method to assess the clinical gravity of asthma than FEV 1. The reduction of FRC in the supine position probably explains the greater incidence of FL in supine position. CONCLUSION: Because of its easy execution, NEP seems to be well adapted for children. Links between FL detected by NEP and clinical signs of asthma has to be assessed by furthers studies including more patients.
Subject(s)
Asthma/diagnosis , Adolescent , Asthma/physiopathology , Child , Exhalation/physiology , Forced Expiratory Volume/physiology , Functional Residual Capacity/physiology , Humans , Inspiratory Capacity/physiology , Lung Diseases, Obstructive/physiopathology , Maximal Expiratory Flow-Volume Curves/physiology , Plethysmography , Posture , Prospective Studies , Pulmonary Ventilation/physiology , Residual Volume/physiology , Spirometry , Status Asthmaticus/physiopathology , Supine Position , Total Lung Capacity/physiology , Vital Capacity/physiologyABSTRACT
Cystic fibrosis (CF) eventually leads to hyperinflation linked to tidal expiratory flow limitation (FL) and ventilatory failure. Presence of FL was assessed at rest in 22 seated children and adults with CF (forced expiratory volume in one second (FEV1) range: 16-92% predicted), using both the negative expiratory pressure (NEP) technique and the "conventional" method based on comparison of tidal and maximal expiratory flow/volume curves. In addition, chronic dyspnoea was scored with the modified Medical Research Council (MRC) scale. Measurements were made before and 15 min after inhalation of salbutamol. With NEP, FL was present in only three malnourished patients, who had the lowest FEV1 values (16-27% pred) and claimed very severe dyspnoea (MRC score 5). By contrast, an additional seven patients were classified as FL with the conventional method. Six of these patients had little or no dyspnoea (MRC scores 0-1). Salbutamol administration had no effect on the extent of FL, and the concomitant decrease in functional residual capacity (FRC) was too small to play any clinically significant role. This study concluded that in seated patients with cystic fibrosis, expiratory flow limitation is absent at rest, unless the forced expiratory volume in one second is <30% predicted. If present, expiratory flow limitation is associated with severe chronic dyspnoea. The conventional method for assessing expiratory flow limitation is not reliable and bronchodilator administration has little effect on expiratory flow limitation.
Subject(s)
Cystic Fibrosis/complications , Dyspnea/etiology , Forced Expiratory Flow Rates , Adolescent , Adult , Airway Resistance , Bronchodilator Agents/administration & dosage , Child , Chronic Disease , Cystic Fibrosis/drug therapy , Dyspnea/diagnosis , Dyspnea/drug therapy , Expiratory Reserve Volume , Female , Humans , Male , Probability , Prospective Studies , Sensitivity and Specificity , Severity of Illness Index , Spirometry , Statistics, Nonparametric , Tidal VolumeABSTRACT
OBJECTIVE: A longitudinal evaluation of lung involvement in primary Sjögren's syndrome (SS). METHODS: Eighteen non-smoking women fulfilling the European criteria for primary SS were followed for 55 months (range 26-137 mos.). These were consecutive patients with exclusion for current smokers and patients with lung diseases. Every patient underwent clinical examination, chest radiographs and lung function tests (spirography, flow/volume loop and CO lung diffusing capacity measurements). No patient was given any immunosuppressive or mucolytic therapy. RESULTS: Cough, dyspnea on exertion and recurrent bronchitis were observed in 50, 40 and 20% of the patients respectively and their frequency did not change with time. Chest radiographs were and remained normal. At presentation, lung volumes and diffusing capacity were in the normal range, whereas expiratory flows in the small airways tended to be in the low range. With time, the peak expiratory flow (PEF) significantly increased (95.8 +/- 4.6 v 103.5 +/- 4.6, mean +/- SE, % of predicted, Wilcoxon, p < 0.05) whereas the lung transfer factor for CO (TLCO) and the transfer coefficient (KCO = TLCO/alveolar volume) decreased (92.9 +/- 4.0 v 87.0 +/- 4.0 and 89.7 +/- 2.4 v 84.2 +/- 2.6 respectively, p < 0.05 for both). The TLCO decrease, corrected for the duration of follow-up, correlated with the titers of IgA circulating immune complexes (CIC) at presentation and to a lesser extent with the occurrence of cough. CONCLUSION: During the follow-up of these primary SS patients, respiratory symptoms did not change, the recurrent respiratory infection rate was low, and no cases of pulmonary hypertension or lymphoma was observed. The diffusion capacity decrease was associated with IgA CIC titers at presentation. This impairment could contribute to dyspnea during its evolution over a lifetime but is too slight to explain the dyspnea on exertion seen in most of our patients.