Spirometry in young children: should computer-animation programs be used during testing?

The effect of medical clowns on performance of spirometry among preschool aged children

INTRODUCTION

Medical clowns (MCs) are known to assist in reducing pain and alleviating anxiety. The objective of this study is to evaluate the ability of MCs to assist preschoolers in performing spirometry.

METHODS

A prospective, randomized controlled trial. Children aged 3-6 years participated. After a first spirometry, children were divided into two groups: the first performed a second spirometry with an MC. The second repeated spirometry with the technician. Primary outcome was second spirometry values compared between the groups. Secondary outcome were change in spirometry values within groups, and difference between the groups.

RESULTS

A total of 140 children participated. The groups did not differ in age, sex, mother tongue, or weight. Nor in mean FVC (MC 89.2% ± 16.7, control 89.5% ± 16.3) mean FEV1 (MC 91.3% ± 15.6, control 94.2% ± 16.8), and expiratory time (MC 1.58 ± 0.43, control 1.7 ± 0.44) in first spirometry. In second spirometry the control group had a similar FVC, FEV1, and expiratory time. The MC group had a significant improvement in all parameters: FVC: MC 95.3% ± 15.5, control 89.3% ± 19.1, FEV1: MC 98.0% ± 15.6, control 91.8% ± 19.3, and expiratory time MC 1.96 ± 0.55, control 1.84 ± 0.52. The differences between the groups between first and second attempt were significant (P-value FVC 0.000, FEV1 0.000, expiratory time 0.003).

DISCUSSION

MCs improved performance of spirometry among preschoolers. It is possible that laughter and relief of stress had a physiological effect. Further studies are required to better establish the ability of MCs to improve active participation and to better understand whether the mechanism of the improvement is better cooperation or true physiological change.

Spirometry interpretation feasibility among pre-school children according to the European Respiratory Society and American Thoracic Society Guidelines

INTRODUCTION

Spirometry is the most used test to evaluate pulmonary function. Guidelines that defined acceptability and repeatability criteria for its implementation and interpretation among preschoolers were published in 2007. Our objective was to quantify the actual compliance with these criteria among pre-school patients.

METHODS

A review was performed on the baseline spirometry measured in patients aged 2 to 5 years in the Pediatric Respiratory Laboratory of the Pontificia Universidad Católica de Chile, who were admitted due to recurrent or persistent coughing or wheezing. Only those results obtained in patients who took the test for the first time were considered. They were analyzed by international standards.

RESULTS

A total of 93 spirometry results (mean age 57.4 ± 8.6 months, 48 males) were obtained, of which 44 (47%) met all acceptable criteria, 87 (93%) obtained expiratory time of ≥ 0.5seconds, and 67 (72%) of the patients had an end-expiratory flow of ≤10% from peak flow. The variation in the measurement of forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) was very low (intraclass correlation coefficient > 0.9).

CONCLUSION

It was possible to meet the acceptability and repeatability criteria for spirometry among pre-school children in our Center, which was similar to previous reports. As in older children, this test is fully recommended for pre-school children who require lung function studies.

Maximal flow at functional residual capacity in asthmatic preschool children

BACKGROUND

Many preschool children will perform correct peak-flow but will not exhale to residual volume, thus limiting the determination of airways obstruction. The maximal flow measured at function residual capacity (V'maxFRC) is independent of lung empting and could potentially serve as a parameter for describing flow at low lung volumes. The study determines the detection of airway obstruction/dilation in asthmatic preschool children by V'maxFRC, compared to FEV1 and FEF25-75.

METHODS

Children performed bronchial provocation test (BPT; n = 26) or received bronchodilators (Post-BD; n = 31). V'maxFRC was extracted at inspiratory capacity point of flow/volume maneuvers. The %change of V'maxFRC from baseline was compared with changes in various spirometry indices and to values obtained from our previously studied healthy control children.

RESULTS

FEV1, FEF25-75, and V'maxFRC decreased by 30.9 ± 12.2%, 46.2 ± 10.9%, and 36.6 ± 8.0%, respectively, while FRC increased by 37.0 ± 24.9% at end of the BPT. Post-BD spirometry values increased by 17.1 ± 16.1%, 47.0 ± 42.2, and 45 ± 24%, respectively (p < 0.0001). A positive response to bronchodilators was observed in 15/31 (48%) children by FEV1, in 22/31 (71%) children by V'maxFRC, and in 21/31 children by FEF25-75.

CONCLUSION

V'maxFRC detects airway obstruction/dilation in young asthmatic children similar to FEF25-75 and FEV1. V'maxFRC may be a valuable index in preschool children who cease exhalation prematurely. Digitally measured V'maxFRC should confirm the actual values in a wider age range in healthy and disease states.

Spirometry in children

Respiratory disorders are responsible for considerable morbidity and mortality in children. Spirometry is a useful investigation for diagnosing and monitoring a variety of paediatric respiratory diseases, but it is underused by primary care physicians and paediatricians treating children with respiratory disease. We now have a better understanding of respiratory physiology in children, and newer computerised spirometry equipment is available with updated regional reference values for the paediatric age group. This review evaluates the current literature for indications, test procedures, quality assessment, and interpretation of spirometry results in children. Spirometry may be useful for asthma, cystic fibrosis, congenital or acquired airway malformations and many other respiratory diseases in children. The technique for performing spirometry in children is crucial and is discussed in detail. Most children, including preschool children, can perform acceptable spirometry. Steps for interpreting spirometry results include identification of common errors during the test by applying acceptability and repeatability criteria and then comparing test parameters with reference standards. Spirometry results depict only the pattern of ventilation, which may be normal, obstructive, restrictive, or mixed. The diagnosis should be based on both clinical features and spirometry results. There is a need to encourage primary care physicians and paediatricians treating respiratory diseases in children to use spirometry after adequate training.

Reference standards for forced expiratory indices in Chinese preschool children

Spirometric testing is traditionally achievable in children of school-age and beyond. Incorporation of interactive incentives motivates preschool children to facilitate measurement of forced expiratory indices. Validated spirometric reference standards are available for Caucasian preschoolers but lacking in Asians. We established spirometric references in Chinese children aged 2-7 years, who were recruited from 19 randomly selected nurseries and kindergartens in Hong Kong. Parents completed International Study of Asthma and Allergies in Childhood questionnaire, and children concurrently performed incentive spirometry on-site according to international guideline. Prediction equations for spirometric indices were formulated by linear regression. One thousand four hundred two (72.9%) of 1,922 consented children, with mean (SD) age 4.4 (1.0) years, successfully performed spirometry. Following exclusions due to medical and technical reasons, 895 (63.8%) children contributed spirometric data to our references. Girls had lower FEV0.5 , FEV0.75 , FEV1 , FVC, and PEF but similar FEF25-75 than boys, adjusted for age, weight, and standing height as covariates. Standing height was the most important predictor for FEV0.5 , FEV0.75 , FEV1 , FVC, and PEF in both boys (adjusted R(2) 0.525-0.734) and girls (adjusted R(2) 0.583-0.721), whereas the best prediction model for both gender is formed by standing height, weight, and age. At various standing heights, our preschoolers had FEV1 Z-scores 0.13-1.00 higher than those of collaborative Caucasian reference. This study justifies the need for ethnic-specific reference equations and presents spirometry references in young Chinese children. Their forced expiratory indices are determined by gender, age, weight and standing height, and standing height is the best anthropometric index to predict all spirometric indices.

Acceptability and repeatability of spirometry in children using updated ATS/ERS criteria

Spirometry in pediatrics can be limited by the child's development which is usually related to age. In 2005 the American Thoracic Society (ATS) and European Respiratory Society (ERS) published updated quality control criteria for spirometry. In 2007 the ATS/ERS published specific criteria for spirometry in preschool children 6 years of age and younger. Our primary objective was to determine the influence of age on the ability of children to meet updated spirometry criteria for acceptable and repeatable tests. Our second objective was to determine which criteria are associated with unacceptable tests. Data was prospectively collected over 12 months for children 4-17 years of age performing spirometry for the first time. Unsuccessful tests were analyzed to determine specific criteria not achieved. Three hundred ninety-three studies were collected and 292 (74%) met recently revised ATS/ERS criteria for acceptable and repeatable tests. Acceptable and repeatable test success was not correlated to the gender or race of the children. The percentage of acceptable and repeatable spirometry increased with age rising above 50% by age 6 and reached a plateau with approximately 85% success at age 10. The most common unmet criteria for an unacceptable study among preschool children was glottic closure and non-maximal efforts, while in school-age children was failure to plateau. These data demonstrate most children are able to perform acceptable/repeatable spirometry with their first effort based on revised ATS/ERS criteria.

Spirometric pulmonary function in 3- to 5-year-old children

Forced expiratory maneuvers are routinely used in children, 6 years of age and older for the diagnosis and follow-up of respiratory diseases. Our objective was to establish normative data for an extensive number of parameters measured during forced spirometry in healthy 3- to 5-year-old children. Children aged between 3 and 5 years were tested in 11 daycare centers. Usual parameters, including FEV1, FVC, PEF, FEF(25-75), FEF25, FEF50, FEF75, and Aex were measured and analyzed in relation to sex, age, height, and weight. In addition, the same analysis was performed for FEV0.5 and FEV0.75. One hundred sixty-four children were recruited for testing including 87 girls and 77 boys. Thirty-five were 3 years old, 63 were 4 years old, and 66 were 5 years old. Overall, 143 children (87%) accepted to perform the test and 128 children (78%) were able to perform at least two technically acceptable expiratory maneuvers. Analyses using different regression models showed that height was the best predictor for every parameter. In conclusion, the present study confirms that most healthy 3-5 years old children can perform valid forced expiratory maneuvers. In agreement with other studies, we found that height is the most important single predictor of various parameters measured on forced spirometry. The present study is the first to establish normative values for FEV0.75, as well as to demonstrate that Aex can be easily performed in the majority of children aged 3-5 years. These are likely important parameters of lung function in this age range.

Reference values of Forced Expiratory Volumes and pulmonary flows in 3-6 year children: a cross-sectional study

BACKGROUND

The aims of this study were to verify the feasibility of respiratory function tests and to assess their validity in the diagnosis of respiratory disorders in young children.

METHODS

We performed spirometry and collected information on health and parents' lifestyle on a sample of 960 children aged 3-6.

RESULTS

The cooperation rate was 95.3%. Among the valid tests, 3 or more acceptable curves were present in 93% of cases. The variability was 5% within subjects in 90.8% of cases in all the parameters. We propose regression equations for FVC (Forced Vital Capacity), FEV1, FEV0.5, FEV0.75 (Forced Expiratory Volume in one second, in half a second and in 3/4 of a second), and for Maximum Expiratory Flows at different lung volume levels (MEF75, 50, 25). All parameters are consistent with the main reference values reported in literature. The discriminating ability of respiratory parameters versus symptoms always shows a high specificity (>95%) and a low sensitivity (<20%) with the highest OR (10.55; CI 95% 4.42-25.19) for MEF75. The ability of FEV0.75 to predict FEV1 was higher than that of FEV0.50: FEV0.75 predicts FEV1 with a determination coefficient of 0.95.

CONCLUSION

Our study confirms the feasibility of spirometry in young children; however some of the current standards are not well suited to this age group. Moreover, in this restricted age group the various reference values have similar behaviour.

Spirometry

Recent data indicate that clinicians and researchers should dismiss the myth that preschoolers are unable to perform spirometry. Reproducible, acceptable flow-volume curves are possible in this age group; however, modifications to the ATS/ERS adult criteria are critical due to physiologic differences. Reference data is available and the clinical applicability of this technique is being evaluated.

Spirometry in the diagnosis of asthma in children

PURPOSE OF REVIEW

To review the diagnostic accuracy of lung function measurements made using spirometry for childhood asthma, recent guidelines for the measurement and interpretation of spirometric lung function tests and recent developments for diagnosing asthma.

RECENT FINDINGS

Measurements of lung function and bronchial lability made using spirometry may not perform any better than other tests such as skin prick testing, or measurements of exhaled nitric oxide for diagnosing asthma. New guidelines are available.

SUMMARY

Spirometry is a simple, robust and widely available tool for investigating lung function. There are published guidelines for making measurements and their interpretation. The place of spirometry in the diagnosis of asthma, however, needs clarification. The diagnostic profiles of measurements of bronchodilator responsiveness and bronchial hyperreactivity made using spirometry, although reasonable, are not perfect. In schoolchildren, they are no better than knowledge of aeroallergen sensitization when considering a diagnosis of asthma.

The role of computer games in measuring spirometry in healthy and "asthmatic" preschool children

STUDY OBJECTIVES

To explore the role of respiratory interactive computer games in teaching spirometry to preschool children, and to examine whether the spirometry data achieved are compatible with acceptable criteria for adults and with published data for healthy preschool children, and whether spirometry at this age can assess airway obstruction.

DESIGN

Feasibility study.

SETTINGS

Community kindergartens around Israel and a tertiary pediatric pulmonary clinic.

PARTICIPANTS

Healthy and asthmatic preschool children (age range, 2.0 to 6.5 years).

INTERVENTION

Multi-target interactive spirometry games including three targets: full inspiration before expiration, instant forced expiration, and long expiration to residual volume.

MEASUREMENTS AND RESULTS

One hundred nine healthy and 157 asthmatic children succeeded in performing adequate spirometry using a multi-target interactive spirometry game. American Thoracic Society (ATS)/European Respiratory Society spirometry criteria for adults for the start of the test, and repeatability were met. Expiration time increased with age (1.3 +/- 0.3 s at 3 years to 1.9 +/- 0.3 s at 6 years [+/- SD], p < 0.05). FVC and flow rates increased with age, while FEV1/FVC decreased. Healthy children had FVC and FEV1 values similar to those of previous preschool studies, but flows were significantly higher (> 1.5 SD for forced expiratory flow at 50% of vital capacity [FEF50] and forced expiratory flow at 75% of vital capacity [FEF75], p < 0.005). The descending part of the flow/volume curve was convex in 2.5- to 3.5-year-old patients, resembling that of infants, while in 5- to 6-year-old patients, there was linear decay. Asthma severity by Global Initiative for Asthma guidelines correlated with longer expiration time (1.7 +/- 0.4 s; p < 0.03) and lower FEF50 (32 to 63%; p < 0.001) compared to healthy children. Bronchodilators improved FEV1 by 10 to 13% and FEF50 by 38 to 56% of baseline.

CONCLUSIONS

Interactive respiratory games can facilitate spirometry in very young children, yielding results that conform to most of the ATS criteria established for adults and published data for healthy preschool children. Spirometric indexes correlated with degree of asthma severity.

Methacholine bronchial provocation measured by spirometry versus wheeze detection in preschool children

BACKGROUND

Determination of PC20-FEV1 during Methacholine bronchial provocation test (MCT) is considered to be impossible in preschool children, as it requires repetitive spirometry sets. The aim of this study was to assess the feasibility of determining PC20-FEV1 in preschool age children and compares the results to the wheeze detection (PCW) method.

METHODS

55 preschool children (ages 2.8-6.4 years) with recurrent respiratory symptoms were recruited. Baseline spirometry and MCT were performed according to ATS/ERS guidelines and the following parameters were determined at baseline and after each inhalation: spirometry-indices, lung auscultation at tidal breathing, oxygen saturation, respiratory and heart rate. Comparison between PCW and PC20-FEV1 and clinical parameters at these end-points was done by paired Student's t-tests.

RESULTS AND DISCUSSION

Thirty-six of 55 children (65.4%) successfully performed spirometry-sets up to the point of PCW. PC20-FEV1 occurred at a mean concentration of 1.70+/-2.01 mg/ml while PCW occurred at a mean concentration of 4.37+/-3.40 mg/ml (p < 0.05). At PCW, all spirometry-parameters were markedly reduced: FVC by 41.3+/-16.4% (mean +/-SD); FEV1 by 44.7+/-14.5%; PEFR by 40.5+/-14.5 and FEF25-75 by 54.7+/-14.4% (P < 0.01 for all parameters). This reduction was accompanied by de-saturation, hyperpnoea, tachycardia and a response to bronchodilators.

CONCLUSION

Determination of PC20-FEV1 by spirometry is feasible in many preschool children. PC20-FEV1 often appears at lower provocation dose than PCW. The lower dose may shorten the test and encourage participation. Significant decrease in spirometry indices at PCW suggests that PC20-FEV1 determination may be safer.

Quality control for spirometry in preschool children with and without lung disease

The reliability of spirometry is dependent on strict quality control. We examined whether quality control criteria recommended for adults could be applied to children aged 2-5 years. Forty-two children with cystic fibrosis and 37 healthy children attempted spirometry during their first visit to our laboratory. Whereas 59 children (75%) were able to produce a technically satisfactory forced expiration lasting 0.5 second, only 46 (58%) could produce an expiration lasting 1 second, with the youngest children having the most difficulty. Start of test criteria for adults were inappropriate for this age group, with only 16 of 59 children producing a volume of back extrapolation as a proportion of forced vital capacity of less than 5%, whereas all but 4 could produce a volume of back extrapolation of 80 ml or less. More than 90% of children were able to produce a second forced vital capacity and a second forced expired volume in 0.75 second within 10% of their highest. Errors in the spirometry software resulted in inaccurate reporting of expiratory duration and inappropriate timed expired volumes in some children. We describe recommendations for modified start of test and repeatability criteria for this age group, and for improvements in software to facilitate better quality control.