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Peak Expiratory Flow (peak + expiratory_flow)
Terms modified by Peak Expiratory Flow Selected AbstractsResistive load of laryngeal mask airway and proseal laryngeal mask airway in mechanically ventilated patientsACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 6 2003G. Natalini Background:, The ProSeal Laryngeal Mask Airway (PLMA) ventilation tube is narrower and shorter than the standard Laryngeal Mask Airway (LMA) and is without the vertical bars at the end of the tube. In this randomized, crossover study, PLMA and LMA resistances were compared. Methods:, Respiratory mechanics was calculated in 26 anesthetized, mechanically ventilated patients with both LMA and PLMA. The laryngeal mask positioning was fiberoptically evaluated. Differences in the respiratory mechanics of the LMA and the PLMA were attributed to the differences between the laryngeal masks. Results:, In the total study population the airway resistance was 1.5 ± 2.6 hPa.l,1.s,1 (P = 0.005) higher with the PLMA than with the LMA. During the PLMA use, the peak expiratory flow reduced by 0.02 ± 0.05 l min,1 (P = 0.046), the expiratory resistance increased by 0.6 ± 1.3 hPa.l,1.s,1 (P = 0.022), and the time constant of respiratory system lengthened by 0.09 ± 0.18 s (P = 0.023). These differences doubled when the LMA was better positioned than the PLMA, whereas they disappeared when the PLMA was positioned better than the LMA. Conclusions:, The standard LMA offers a lower resistive load than the PLMA. Moreover, the fitting between the laryngeal masks and the larynx, as fiberoptically evaluated, plays a major role in determining the resistive properties of these devices. [source] Budesonide/formoterol improves lung function compared with budesonide alone in children with asthma,PEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 6 2006Petr Pohunek We aimed to compare the efficacy and safety of budesonide/formoterol (Symbicort®) with budesonide alone (Pulmicort®) or budesonide (Pulmicort) and formoterol (Oxis®) administered via separate inhalers in children with asthma. In a 12 wk, double-blind study, a total of 630 children with asthma (mean age 8 yr [4,11 yr]; mean forced expiratory volume in 1 s (FEV1) 92% predicted; mean inhaled corticosteroid dose 454 ,g/day) were randomized to: budesonide/formoterol (80/4.5 ,g, two inhalations twice daily); a corresponding dose of budesonide alone (100 ,g, two inhalations twice daily); or a corresponding dose of budesonide (100 ,g, two inhalations twice daily) and formoterol (4.5 ,g, two inhalations twice daily) (budesonide + formoterol in separate inhalers). The primary efficacy variable was the change from baseline to treatment (average of the 12-wk treatment period) in morning peak expiratory flow (PEF). Other changes in lung function and asthma symptoms were assessed, as was safety. Budesonide/formoterol significantly improved morning PEF, evening PEF and FEV1 compared with budesonide (all p < 0.001); there was no significant difference between budesonide/formoterol and budesonide + formoterol in separate inhalers for these variables. All other diary card variables improved from baseline in all treatment groups; there were no significant between-group differences. Adverse-event profiles were similar in all groups; there were no serious asthma-related adverse events in any treatment group. Conclusion: budesonide/formoterol significantly improved lung function in children (aged 4,11 yr) with asthma compared with budesonide alone. Budesonide/formoterol is a safe and effective treatment option for children with asthma. [source] Is home spirometry useful in diagnosing asthma in children with nonspecific respiratory symptoms?,PEDIATRIC PULMONOLOGY, Issue 4 2010Alwin F.J. Brouwer MD Abstract Background Variation of lung function is considered to be a hallmark of asthma. Although guidelines recommend measuring it as a diagnostic tool for asthma, the usefulness of this approach has not been studied in children. Aim To assess the usefulness of home spirometry in children with nonspecific lower respiratory tract symptoms, to diagnose or exclude asthma. Methods In school-aged children, referred by their general practitioner because of chronic respiratory symptoms of unknown origin, the diagnosis of asthma was made or excluded by a pediatric pulmonologist (gold standard), based on international guidelines and a standardized protocol. Additionally, children measured peak expiratory flow (PEF) and forced expiratory flow in 1,sec (FEV1) twice daily for 2 weeks on a home spirometer, from which diurnal variation was calculated. These results (index test) were not revealed to the pediatric pulmonologist. The value of home spirometry to diagnose asthma was calculated. Results Sixty-one children (27 boys) were included (mean age: 10.4 years; range: 6,16 years). Between asthma and no asthma, the mean difference in PEF variation was 4.4% (95% CI: 0.9,7.9; P,=,0.016) and in FEV1 variation 4.5% (95% CI: 1.6,7.4; P,=,0.003). Sensitivity and specificity, based on the 95th-centile of the reference values for PEF and FEV1 variation (12.3% and 11.8%, respectively) were 50% and 72% for PEF variation and 45% and 92% for FEV1 variation. The likelihood ratio was 1.8 for PEF and 5.6 for FEV1. Conclusions The contribution of home spirometry in the diagnostic process for asthma in schoolchildren with nonspecific respiratory symptoms is limited. Pediatr Pulmonol. 2010; 45:326,332. © 2010 Wiley-Liss, Inc. [source] Forced inspiratory flow volume curve in healthy young childrenPEDIATRIC PULMONOLOGY, Issue 2 2009Daphna Vilozni PhD Abstract Introduction Spirometry testing should include both expiratory and inspiratory measurements. Inspiratory forced maneuvers can demonstrate extrathoracic airway abnormalities, of which various symptoms may suggest asthma. However, the inspiratory portion of the forced flow/volume maneuver in young healthy children has not yet been described. Objectives To document and analyze the forced inspiratory flow volume curve indices in healthy young children. Settings and Participants Healthy preschool children (age 2.5,6.5 years) from community kindergartens around Israel. Methods The teaching method included multi-target, interactive spirometry games and accessory games for inspiration (e.g., inspiratory whistle). Results One hundred and fourteen out of a total of 157 children performed duplicate full adequate inspiratory maneuvers. Repeatability between two maneuvers was 5.6%, 4.0%, 5.1%, 7.3% for inspiratory capacity (IC), forced inspiratory vital capacity (FIVC), peak inspiratory flow (PIF), and mid inspiratory flow (FIF50). Inspiratory flow indices were significantly lower than the expiratory flow indices. The time to reach PIF was significantly longer (mean,±,SD; 229,±,21 msec) than the time to reach peak expiratory flow (92,±,8 msec; P,<,0.0001). The shape of the inspiratory curve was parabolic and did not vary with age. The formed predicted equations were in agreement with the extrapolated values for older healthy children. Conclusions The majority of healthy young children can perform reliable maximum inspiratory flow volume curves. Our results provide a framework of reference equations for maximum inspiratory flow volume curve in the young children. The clinical applications of these equations have to be explored. Pediatr Pulmonol. 2009; 44:105,111. © 2009 Wiley-Liss, Inc. [source] Suppression of plasma matrix metalloproteinase-9 following montelukast treatment in childhood asthmaPEDIATRICS INTERNATIONAL, Issue 6 2007SHIH-SUNG CHUANG Abstract Background: Montelukast and ketotifen are commonly prescribed anti-inflammatory medications used in the treatment of childhood asthma. Methods: To investigate the modulation effect of montelukast and ketotifen, the levels of exhaled nitric oxide (eNO) and plasma matrix metalloproteinase-9 (MMP-9) were analyzed in a group of 30 children with mild persistent asthma. Results: Patients on montelukast therapy for 8 weeks had significantly decreased levels of eNO and plasma MMP-9, which were associated with improved symptoms and enhanced peak expiratory flow but not significantly associated with increased level of tissue inhibitor metalloproteinase-1 (TIMP-1). In contrast, treatment with ketotifen produced no significant changes in these parameters until 4,6 weeks into the therapy and no effect on plasma MMP-9. Conclusion: Leukotriene antagonists, such as montelukast, may be better non-steroidal anti-inflammatory drugs for preventing airway inflammation in mild childhood asthma. [source] Stability of genetic influences on pulmonary function in a longitudinal study of octogenarian twinsAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 3 2010Terrie Vasilopoulos Using data from the first four waves of the OCTO-Twin study (twins 80 + years), the present study investigated the stability and change of genetic and environmental contributions to pulmonary function. Using a genetic simplex model, variance in peak expiratory flow (PEF) at each wave was decomposed into additive genetic and nonshared (specific) environmental factors. Additionally, this analysis distinguished the source of these influences, either from previous waves (transmissions) or from novel influences at each wave (innovations). At each time point (except wave 1), the genetic variance was due to genetic transmissions from prior time points. Conversely, the specific environmental variance in PEF at each time point was mainly due to environmental innovations. These results imply that genetic factors contribute to the stability of pulmonary function over time whereas environmental factors contribute to its change. Am. J. Hum. Biol., 2010. © 2009 Wiley-Liss, Inc. [source] Flow,volume curve changes in patients with obstructive sleep apnoea and brief upper airway dysfunctionRESPIROLOGY, Issue 1 2000Alastair H Campbell Objective: Patients with obstructive sleep apnoea (OSA) and those with brief upper airway dysfunction (BUAD) have been reported to have abnormalities of maximal flow,volume curves. This study was designed to assess the ability of flow,volume curves to predict the presence of OSA or BUAD. Methodology: Four maximal flow,volume manoeuvres performed by 33 OSA patients and 16 BUAD patients were compared with those of 36 normal subjects. Flow,volume indices, their variability, saw-toothing in the curve and an algorithm based on the flow ratios and shape of the curves were assessed. Results: When the confounding factors, body mass index (BMI), age, gender and smoking status were taken into account, there was no significant difference in a variety of indices derived from the flow,volume curves between OSA and normal subjects. No BUAD patient had normal flow,volume curves as determined with the algorithm. After BMI, age, gender and smoking status were accounted for, decreased forced expiratory volume in 1 s (FEV1), and increased variability of peak expiratory flow (PEF)/peak inspiratory flow (PIF) and FEV1/PEF remained significantly associated with BUAD. Conclusions: These findings suggest that flow,volume curve indices have no value in predicting OSA. Some abnormalities are found in patients with BUAD; a normal flow,volume curve makes the diagnosis of BUAD unlikely. [source] Airway obstruction at time of symptoms prompting use of reliever therapy in children with asthmaACTA PAEDIATRICA, Issue 6 2010AFJ Brouwer Abstract Background:, In asthma treatment, doses of inhaled corticosteroids are often adapted to symptoms and need for bronchodilators. However, in cross-sectional studies in emergency room settings, lung function and respiratory symptoms are not always concordant. Available longitudinal data are based on written peak flow diaries, which are unreliable. Using home spirometry, we studied prospectively whether mild respiratory symptoms, prompting reliever therapy are accompanied by a clinically relevant drop in lung function in children with asthma. Methods:, For 8 weeks, children with asthma scored symptoms and measured peak expiratory flow (PEF) and forced expiratory volume in 1 sec (FEV1) on a home spirometer twice daily. Additional measurements were recorded when respiratory symptoms prompted them to use bronchodilators. Results:, The mean difference between symptom free days and at times of symptoms was 6.6% of personal best for PEF (95% CI: 3.2,10.0; p = 0.0004) and 6.0% of predicted for FEV1 (95% CI: 3.0,9.0; p = 0.0004). There was complete overlap in PEF and FEV1 distributions between symptom free days and at times of symptoms. Conclusions:, Although statistically significant, the degree of airway narrowing at times of respiratory symptoms, prompting the use of reliever therapy, is highly variable between patients, limiting the usefulness of home spirometry to monitor childhood asthma. [source] Persistence of rhinovirus RNA after asthma exacerbation in childrenCLINICAL & EXPERIMENTAL ALLERGY, Issue 5 2005S. Kling Summary Background Rhinoviruses (RVs) are believed to cause most asthma exacerbations but their role in the severity of acute asthma and subsequent recovery of airway function is not defined. The importance of atopy in virus-host interactions is also not clear. Objective We postulated that RV infection and atopic skin prick responses influence the severity of asthma exacerbations as measured by peak expiratory flow (PEF). Methods Patients aged 4,12 years admitted with acute severe asthma to a hospital emergency room (ER) were recruited. PEF measurements were obtained and nasal aspirates (NA) were taken. Atopy was diagnosed by skin prick responses to allergen and the presence of RV RNA and respiratory syncytial virus (RSV) RNA in NAs was detected using validated PCR assays. Patients were restudied after 6 weeks and after 6 months. Results Fifty children with acute asthma (mean age±SD, 7.4±2.7) were enrolled; atopy was present in 37 (74%). RV RNA was detected in 41 (82%) and RSV RNA in six (12%) subjects. After 6 weeks 41 patients were restudied and RV RNA was again detected in 18 (44%). RV RNA was detected after 6 months in four of 16 patients restudied (25%; P=0.008 vs. ER) and in two of nine children from a control group with stable asthma (22%; P=0.009 vs. ER). Overall PEF measurements were reduced in asthmatics admitted to ER (% predicted, 63.4±16.4%) but did not differ between patients with RV RNA, RSV RNA or neither virus present. In subjects with RV RNA detectable in ER and after 6 weeks, measurements of PEF in ER were significantly lower than in patients in whom RV RNA was present in ER but absent after 6 weeks (P=0.009). Regression analysis linked persistence of RV RNA, but not skin prick responses to allergen, to severity of PEF reductions in ER. Conclusion RV RNA was detectable in >40% of asthmatic children 6 weeks after an acute exacerbation. Asthma exacerbations were more severe in patients with persistence of RV RNA suggesting that the severity of acute asthma may be linked to prolonged and possibly more severe RV infections. [source] The effectiveness of intranasal corticosteroids in combined allergic rhinitis and asthma syndromeCLINICAL & EXPERIMENTAL ALLERGY, Issue 12 2004P. Taramarcaz Summary Background Allergic rhinitis (AR) and asthma often coexist and may represent two manifestations of the same disease recently named combined AR and asthma syndrome (CARAS). Aim To review the common pathophysiology of combined AR and asthma and to investigate the efficacy of intranasal corticosteroids (INCS). Methods Medline was used to identify articles relevant to mechanisms. A Cochrane systematic review was performed to assess the efficacy of INCS in CARAS. Results There is cross-talk, evidence of a common inflammatory response in both sites, linked by a systemic component. The efficacy of anti-inflammatory INCS on asthma outcomes was assessed in a systematic review of 12 randomized controlled trials involving 425 subjects. After INCS there were non-significant trends for improvement in asthma symptom score (standardized mean difference (SMD) of 0.61; P=0.07), forced expiratory volume in 1 s (SMD of 0.31; P=0.08), and morning peak expiratory flow (weighted mean difference of 36.51; P=0.06). There was no impact on methacholine airways responsiveness (SMD of ,0.20; P=0.4). The review identified two promising new treatment options in united airway disease such as INCS as monotherapy in rhinitis and mild asthma, and a combined intranasal and intrabronchial corticosteroid (IBCS) deposition technique. Conclusion Common mucosal inflammatory responses occur in CARAS. This systematic review shows trends for a benefit of INCS in CARAS, but recognizes that more research is needed. At this stage, the current best practice is to treat asthma conventionally with IBCS with or without ,2 -agonist and to add INCS to improve specific rhinitis symptoms. [source] COMPARISON OF THE EFFECTS OF TULOBUTEROL PATCH AND SALMETEROL IN MODERATE TO SEVERE ASTHMACLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 11 2006Osamu Nishiyama SUMMARY 1Although the clinical effects of the tulobuterol patch have been reported to include an increase in morning peak expiratory flow (PEF) values and a decrease of symptoms and the frequency of the rescue use of inhaled short-acting b2 -adrenoceptor agonists, no trials comparing the efficacy of the tulobuterol patch to other standard inhaled long-acting b2 -adrenoceptor agonists have yet been conducted. The aim of the present study was to compare the clinical effects of the patch formulation of tulobuterol with those of inhaled salmeterol in moderate to severe asthma. 2Fifty-four patients with moderate to severe asthma, whose conditions were suboptimally controlled despite receiving inhaled corticosteroids, were recruited. The study was a prospective, randomized trial of cross-over design comparing the effects of 4 weeks treatment with tulobuterol patch, 2 mg once daily, and salmeterol, 50 mg twice daily. The mean prebronchodilator morning PEF during the last 14 days of each treatment period and health-related quality of life (HRQoL) were the primary outcome variables. The HRQoL was assessed using the St George's Respiratory Questionnaire. 3Forty-four patients (81.5%) completed the trial and were included in the analysis. The mean morning PEF and HRQoL score were significantly improved in both the salmeterol (P < 0.0001 and P < 0.05, respectively) and the tulobuterol patch (P < 0.01 and P < 0.05, respectively) treatment periods compared with the run-in period. Although the mean morning PEF was significantly higher in the salmeterol-treated group than in the tulobuterol-treated group (P < 0.001), the HRQoL scores were comparable. 4The tulobuterol patch may be useful as a controller medication in addition to inhaled corticosteroids in moderate to severe asthma. [source] | ||||||||||||||||||||||