Relevance of a portable spirometer for detection of small airways obstruction

Effect of intrathoracic oscillations on pulmonary functions in children with cerebral palsy

Objectives

This study was aimed at investigating the effects of intrathoracic oscillations on pulmonary function in children with spastic quadriplegic cerebral palsy.

Methods

This study comprised 24 boys and girls 6-8 years of age with spastic quadriplegic cerebral palsy. According to the modified Ashworth scale, the degree of spasticity was 2 to 2+. The children were able to sit independently and follow instructions. The children were randomly divided into a study group and control group. A spirometer was used to examine each child before and after 6 weeks. Children in the control group received traditional chest physiotherapy (postural drainage and percussion), whereas children in the study group underwent quake device training. For 6 weeks, both groups received four sessions per week. After treatment, the results were collected. Paired t-test and independent-samples t-test were applied to compare the means for each group. p-values <0.05 were considered significant.

Results

The post-treatment results of forced expiratory volume at 1 s, peak expiratory flow, forced vital capacity, and the ratio of forced expiratory volume at 1 s to forced vital capacity demonstrated significant differences favoring the study group over the control group (p < 0.001, p < 0.001, p = 0.002, and p = 0.023, respectively).

Conclusion

Intrathoracic oscillations may improve pulmonary function in children with quadriplegic cerebral palsy.

Age-related circadian rhythm and variability of large- and small-airway function in healthy non-smoking adults: Data from 7-day diurnal and nocturnal home monitoring using an electronic portable spirometer

Background

The aim of the study was to investigate the possible influencing factors of the large- and small-airway function variation in healthy non-smoking adults.

Methods

Healthy non-medical non-smoking adults were enrolled in this prospective cohort study. Each participant took the portable spirometer test relying only on video teaching. Then conventional spirometry and bronchodilation test were conducted using a Jaeger spirometer, followed by 7-day diurnal and nocturnal home monitoring using a portable spirometer.

Results

A drop in both large- and small-airway function began at about 25 years of age, and a rapidly decline at about 50 years. The CV of FEV₁ (r = 0.47, P = 0.0082) and small-airway function variables correlated with age (r ≥ 0.37, P < 0.05 for both MEFs and MEFs/FVC), especially for evening small-airway function variables. The CV of large (4.666 ± 1.946, P = 0.002 for FEV₁; 4.565 ± 2.478, P = 0.017 for FEV₃) and small airways (10.38 ± 3.196, P = 0.031 for MEF50 and 11.21 ± 4.178, P = 0.023 for MMEF) was higher in the 45- to 60-year subgroup than in the 30- to 45-year and 18- to 30-year subgroups.

Interpretation

Age was the main influencing factor of both central and peripheral airway function variability, especially for the small-airway function in the evening. The LLN of small-airway variables varies depending on the age and circadian rhythm. People older than 45 years should pay more attention to monitoring small-airway function in the evening, which will be helpful for early clinical detection of those at high risk for asthma.

Trial registration number

ChiCTR2100050355.

Pulmonary function parameters in high-resolution computed tomography phenotypes of chronic obstructive pulmonary disease

BACKGROUND

Heterogeneity of clinical presentation of chronic obstructive pulmonary disease (COPD) attributes to different pathological basis. High-resolution computed tomography (HRCT) phenotypes of COPD may reflex the pathological basis of COPD indirectly by evaluating the small airway inflammation and emphysema. How the pulmonary function related with different HRCT phenotypes has not been well known. The aim was to explore the features of pulmonary function parameters in the 3 phenotypes.

METHODS

Sixty-three stable COPD patients were allocated in 3 groups based on HRCT findings: phenotype A (absence of emphysema, with minimal evidence of emphysema with or without bronchial wall thickening [BWT]), phenotype E (emphysema without BWT) and phenotype M (emphysema with BWT). The pulmonary function testing was also analyzed.

RESULTS

The values of forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC%), FEV1% and maximum expiratory flows (MEF)50% were the highest in phenotype A (P < 0.05), so was residual volume (RV)/total lung capacity (TLC%) in phenotype E (P < 0.05). Those with MEF50/MEF25 ratio >4.0 were more prevalence in phenotype A than in E and M (odds ratio = 2.214; P < 0.05). The occurrences of RV/TLC% >40% were higher in phenotype E than in A and M (odds ratio = 3.906; P < 0.05). Receiver operating characteristic analysis showed that the cutoff value of MEF50/MEF25 ratio for identifying phenotype A was 2.5, with sensitivity 66.7% and specificity 92.9%. The cutoff value of RV/TLC% for identifying phenotype E was 57.4%, with sensitivity 75.0% and specificity 79.1%.

CONCLUSIONS

The different features of pulmonary function parameters were found in various HRCT phenotypes; MEF50/MEF25 ratio could imply phenotype A, whereas RV/TLC% may be the indicator of phenotype E.

Utility of portable spirometry in a pediatric emergency department in children with acute exacerbation of asthma

OBJECTIVES

The primary purpose of this study was to determine if portable spirometers can be successfully used in an emergency department (ED) in children with an acute exacerbation of asthma. The secondary purpose of this study was to determine if a validated clinical asthma score (CAS) correlates with the spirometry results in children with an acute exacerbation of asthma.

METHODS

Children between the ages of 6 and 17 years who presented to an urban free-standing children's hospital ED with an acute exacerbation of asthma were enrolled in our study. On arrival, the CAS was recorded and then portable spirometry was performed. Attempts were continued until acceptable and reproducible flow loop measurements were obtained or until the patient was unable to perform further attempts. Outcomes included success at spirometry and correlation of spirometry with the CAS.

RESULTS

A total of 101 patients were enrolled in this study. Of those patients, only 35 (35%) were able to successfully perform portable spirometry. Successful spirometry attempts were associated with older age (10.4 vs. 8.9, p = .01), lower respiratory rates (24.8 vs. 30.2, p = .001), lower heart rates (110 vs. 124, p = .004), and lower CASs (8.4 vs. 9.7, p = .001). Increasing asthma severity correlated with a decreased likelihood of successfully obtaining a useful forced expiratory volume in 1 second (FEV(1)) measurement (p = .013). Compared with cases of mild asthma, a patient with moderate asthma is 33% less likely to be able to perform spirometry, and a patient with severe asthma 93% less likely to perform spirometry. The CAS correlated poorly with the more objective measure of FEV(1)% predicted in those with mild asthma.

CONCLUSION

Many children are incapable of using portable spirometry for the evaluation of acute exacerbations of asthma in the ED. The clinical asthma scoring system demonstrated poor correlation with portable spirometry measurements in terms of severity classification.

Portable spirometry during acute exacerbations of asthma in children

BACKGROUND

Spirometry is the gold standard for assessment of asthma and is objective and non-invasive. This is a pilot study to evaluate whether portable spirometry can be successfully performed by children in the pediatric emergency department for acute exacerbations of asthma.

METHODS

We enrolled children more than 6 years of age presenting to an urban pediatric emergency department with a history of asthma during an acute exacerbation. On arrival and after each bronchodilator treatment, vital signs and a clinical score were recorded. Portable spirometry was then performed. Attempts were continued until acceptable and reproducible measurements were obtained or until the patient was unable to perform further attempts. Outcomes included success at spirometry and correlation of spirometry with clinical signs.

RESULTS

Thirty-four subjects were enrolled with a median age of 12 years. Ninety-one percent of subjects completed at least one attempt at spirometry. Seventy-three percent of all spirometry attempts were reproducible. Portable spirometry demonstrated increased severity of the exacerbation in comparison to clinical signs and peak expiratory flow. Percent of predicted forced expiratory volume in 1 second, ratio of forced expiratory volume in 1 second to forced vital capacity, and peak expiratory flow are all poorly correlated with degree of wheezing, clinical score, respiratory rate, and oxygen saturation (r < 0.5).

CONCLUSION

Portable spirometry can be successfully performed by children with acute exacerbations of asthma in the emergency department and demonstrated greater degrees of airway obstruction than did clinical signs. Spirometry provides objective, non-invasive measurements of the severity of airway obstruction in the emergency department for children with acute exacerbations of asthma.

Telemetric Monitoring of Pulmonary Function After Allogeneic Hematopoietic Stem Cell Transplantation

BACKGROUND

Late-onset noninfectious pulmonary complications (LONIPC) are both frequent and severe after allogeneic hematopoietic stem cell transplantation (HSCT). The high mortality rate (40-80%) may be related to delayed diagnosis. We assessed the use of telemetric home surveillance of pulmonary function for early diagnosis of LONIPC in transplant recipients.

METHODS

This prospective study monitored pulmonary function in 37 allogeneic HSCT recipients. About 3 months after HSCT, they received a portable spirometer that measured forced vital capacity, forced expiratory volume per second, and midexpiratory flow 25-75 (MEF25-75). Data were transmitted twice weekly by telephone. Conventional plethysmography confirmed any significant deterioration (>20%).

RESULTS

Thirteen episodes of spirometric deterioration were detected by telemetry in 11 patients during a median 17-month (4-41) follow-up period after transplantation. In these cases, examinations including spirometry, high-resolution thoracic computed tomography and bronchoalveolar lavage diagnosed LONIPC in eight episodes in seven patients (cumulative incidence 23.4%, SE 0.08, at month 24 after transplant): bronchiolitis obliterans (BO, n=3), interstitial pneumonia (IP, n=4), or both BO and IP (n=1). Five episodes improved and three were stabilized with increased immunosuppressive therapy. At the last follow-up, of the seven patients with LONIPC, one successfully stopped immunosuppressive therapy, two were receiving low-dose mycophenolate mofetil, and four were receiving low-dose corticosteroid therapy. There were no cases of respiratory failure and no patient died from LONIPC.

CONCLUSION

Telemetric home monitoring of pulmonary function is a useful procedure for early diagnosis of LONIPC before clinical pulmonary symptoms and may improve outcome after allogeneic HSCT.