Infant Pulmonary Function Testing Research Articles

Current Approaches in Infant Pulmonary Function Testing

Pulmonary function testing in infants has grown from basic measurements of lung mechanics, volumes and breathing patterns to sophisticated measurements of forced expiratory flows, fractional lung volumes, and sensitive tests of small airway function. New tests continue to be developed that extend our understanding of lung function in health and disease. The indications for infant pulmonary function testing continue to be refined. This review highlights studies that involve some of the techniques, their role in detecting abnormalities in different conditions, and the information that they can provide about several diseases in recent years. Impediments to testing, including need for sedation, labor-intensive nature of the tests and lack of large normative data sets, remain obstacles for more widespread use of the techniques.

Exhaled nitric oxide predicts persistence of wheezing, exacerbations, and decline in lung function in wheezy infants and toddlers.

There are limited data assessing the predictive value of fraction of exhaled nitric oxide (FENO ) for persistence of wheezing, exacerbations, or lung function change over time in infants/toddlers with recurrent wheezing. In an ongoing longitudinal cohort of infants and toddlers with recurrent wheezing, we compared predictive values of single-breath FENO (SB-FENO ), tidal-breathing mixed expired FENO (tidal-FENO ), bronchodilator responsiveness (BDR) and the Castro-Rodriquez Asthma Predictive Index (API) for persistence of wheezing, exacerbations and lung function change through age 3years. Enrolment forced expiratory flows and volumes infant pulmonary function tests (iPFTs) were measured in 44 infants/toddlers using the raised volume rapid thoracoabdominal compression method. SB-FENO was measured at 50mL/s, and tidal-FENO was measured during awake tidal breathing. Clinical outcomes were assessed at age 3years in 42 infants. Follow-up iPFTs were completed between ages 2.5-3years in 32 subjects. An enrolment SB-FENO concentration ≥30p.p.b. predicted persistence of wheezing at age 3years with a sensitivity of 77%, a specificity of 94%, and an area under the curve (AUC) of 0.86 (95% CI: 0.74-0.98). The sensitivity, specificity, positive predictive, and negative predictive values of SB-FENO for persistence of wheezing and exacerbations were superior to tidal-FENO , BDR, and the API. SB-FENO ≥30p.p.b. and tidal-FENO ≥7p.p.b. measured at enrolment was associated with a decline in both FEV0.5 and FEF25-75 between enrolment and age 3years. In wheezy infants/toddlers, SB-FENO was superior to tidal-FENO , BDR, and the API in predicting future exacerbations and persistence of wheezing at age 3years. Both SB-FENO and tidal-FENO were associated with lung function decline over time.

Pulmonary Functions Before and After Pediatric Cardiac Surgery

This study aimed to assess pulmonary functions before and after cardiac surgery in infants with congenital heart diseases and pulmonary overflow and to clarify which echocardiographic parameter correlates best with lung mechanics. Between 2008 and 2009, 30 infants with left-to-right shunt congenital acyanotic heart diseases who had indications for reparative surgery of these lesions were assessed by echocardiography and infant pulmonary function tests before the operation and 6 months afterward. Tests using baby body plethysmography were performed to assess the following infant pulmonary functions: tidal volume, respiratory rate, respiratory system compliance (C(rs)) and respiratory system resistance, functional residual capacity (FRC), and airway resistance. The mean age of the patients was 10.47 ± 3.38 months, and their mean weight was 6.81 ± 1.67 kg. Ventricular septal defect and combined lesions were the predominant cardiac diseases (26.7%). Comparison of the infant pulmonary function tests showed a highly significant improvement in all the parameters between the preoperative and 6-month postoperative visits (p < 0.0001). Systolic pulmonary artery pressure had a statistically significant negative correlation with C(rs) (r = -0.493, p = 0.006) and a positive correlation with FRC (r = 0.450, p = 0.013). The findings showed that C(rs) had a statistically significant negative correlation with the pulmonary artery size (r = -0.398, p = 0.029) and the left atrium size (r = -0.395, p = 0.031), whereas the pulmonary artery size had a statistically positive correlation with effective resistance (r = 0.416, p = 0.022) and specific effective resistance (r = 0.604, p = 0.0001). Surgical correction of left-to-right shunt congenital heart diseases had a positive impact on lung compliance, airway resistance, and FRC. Noninvasive echocardiographic parameters assessing pulmonary vascular engorgement and pulmonary artery pressure were closely related to these infant pulmonary function test indexes.

An Official American Thoracic Society Clinical Practice Guideline: Classification, Evaluation, and Management of Childhood Interstitial Lung Disease in Infancy

There is growing recognition and understanding of the entities that cause interstitial lung disease (ILD) in infants. These entities are distinct from those that cause ILD in older children and adults. A multidisciplinary panel was convened to develop evidence-based guidelines on the classification, diagnosis, and management of ILD in children, focusing on neonates and infants under 2 years of age. Recommendations were formulated using a systematic approach. Outcomes considered important included the accuracy of the diagnostic evaluation, complications of delayed or incorrect diagnosis, psychosocial complications affecting the patient's or family's quality of life, and death. No controlled clinical trials were identified. Therefore, observational evidence and clinical experience informed judgments. These guidelines: (1) describe the clinical characteristics of neonates and infants (<2 yr of age) with diffuse lung disease (DLD); (2) list the common causes of DLD that should be eliminated during the evaluation of neonates and infants with DLD; (3) recommend methods for further clinical investigation of the remaining infants, who are regarded as having "childhood ILD syndrome"; (4) describe a new pathologic classification scheme of DLD in infants; (5) outline supportive and continuing care; and (6) suggest areas for future research. After common causes of DLD are excluded, neonates and infants with childhood ILD syndrome should be evaluated by a knowledgeable subspecialist. The evaluation may include echocardiography, controlled ventilation high-resolution computed tomography, infant pulmonary function testing, bronchoscopy with bronchoalveolar lavage, genetic testing, and/or lung biopsy. Preventive care, family education, and support are essential.

A 2-year-old girl with co-inherited cystic fibrosis and sickle cell-β+ thalassemia presenting with recurrent vaso-occlusive events during cystic fibrosis pulmonary exacerbations: a case report

IntroductionThis is the first published report of a young girl with co-inherited sickle cell-β+ thalassemia and cystic fibrosis. Although a small subset of patients with co-inherited cystic fibrosis and other hemoglobinopathies have been reported, this patient developed early hematologic and pulmonary complications that were more severe than the previous cases. To assess pulmonary co-morbidities, we used infant pulmonary function testing through the raised volume rapid thoracoabdominal compression technique as both an established study of early cystic fibrosis and also as a newer study of mechanism for early sickle cell lung disease. This further serves as the first report of the raised volume rapid thoracoabdominal compression technique to determine raised volume forced expiratory flows and fractional lung volumes in a patient with a hemoglobinopathy.Case presentationA 2-year-old African-American girl with co-inherited cystic fibrosis and sickle cell-β+ thalassemia developed severe hematologic complications (recurrent vaso-occlusive events, hepatic sequestration, and acute chest syndrome) during periods of cystic fibrosis pulmonary exacerbations and weight loss. Because cystic fibrosis and sickle cell-β+ thalassemia both confer distinct patterns of pulmonary disease, infant pulmonary function testing with the raised volume rapid thoracoabdominal compression technique was used to define respiratory pathophysiology and guide treatment options. Infant pulmonary function testing data demonstrated moderate-to-severe lower airways obstruction, moderate air trapping, and no evidence of restrictive lung disease.ConclusionsInfant pulmonary function testing with the raised volume rapid thoracoabdominal compression technique guided therapy in this patient with cystic fibrosis and sickle cell-β+ thalassemia. Although this is an original case report on a unique patient, this case highlights the need to evaluate early respiratory pathophysiology in a broader population of young patients with hemoglobinopathies and screen those at risk for early pulmonary co-morbidities.

Association of lung function, chest radiographs and clinical features in infants with cystic fibrosis

The optimal strategy for monitoring cystic fibrosis lung disease in infancy remains unclear. Our objective was to describe longitudinal associations between infant pulmonary function tests, chest radiograph scores and other characteristics. Cystic fibrosis patients aged ≤24 months were enrolled in a 10-centre study evaluating infant pulmonary function tests four times over a year. Chest radiographs ∼1 year apart were scored using the Wisconsin and Brasfield systems. Associations of infant pulmonary function tests with clinical characteristics were evaluated with mixed effects models. The 100 participants contributed 246 acceptable flow/volume (forced expiratory volume in 0.5 s (FEV0.5) and forced expiratory flow at 75% of the forced vital capacity (FEF75%)), 303 functional residual capacity measurements and 171 chest radiographs. Both Brasfield and Wisconsin chest radiograph scores worsened significantly over the 1-year interval. Worse Wisconsin chest radiograph scores and Staphylococcus aureus were both associated with hyperinflation (significantly increased functional residual capacity), but not with diminished FEV0.5 or FEF75%. Parent-reported cough was associated with significantly diminished forced expiratory flow at 75% but not with hyperinflation. In this infant cohort in whom we previously reported worsening in average lung function, chest radiograph scores also worsened over a year. The significant associations detected between both Wisconsin chest radiograph score and S. aureus and hyperinflation, as well as between cough and diminished flows, reinforce the ability of infant pulmonary function tests and chest radiographs to detect early cystic fibrosis lung disease.

Abnormal infant pulmonary function in young children with neuroendocrine cell hyperplasia of infancy

Lung function in children with neuroendocrine cell hyperplasia of infancy (NEHI) and correlations with future clinical outcomes are needed to guide clinical management. To compare results of infant pulmonary function tests (IPFTs) in children with NEHI to disease control (DC) subjects and to correlate NEHI IPFTs with future outcomes. We performed a retrospective, single center study of IPFT in subjects diagnosed by lung biopsy (NEHI) or clinically (NEHI syndrome) and in DC subjects evaluated for cancer or pre-hematopoietic stem cell transplantation (HSCT). Raised volume rapid thoracoabdominal compression (RVRTC) and plethysmography were performed on all infants and evaluated for quality. Standard spirometry measures, room air oxygen saturations (RA O2 sat), and weight percentiles were collected during follow up. Fifty-seven IPFTs were performed in 15 NEHI, 22 NEHI syndrome, and 20 DC subjects. RVRTC and FRC measurements were obtained in 85% or more of subjects in all groups. Significant airflow limitation (FEV0.5 P-value ≤ 0.01) and air trapping (FRC P-value ≤ 0.01) were seen in NEHI and NEHI syndrome subjects compared to DCs. No significant correlations were found between IPFT, oxygen use, RA O2 sat, and weight at the time of the IPFTs. Initial FEV0.5 and FRC z-scores correlated with RA O2 sat (r = 0.60 and -0.49) at short-term follow up (6-12 months). Most measurements of RVRTC correlated with FEV1 (n = 5) measured 4-5 years later (r > 0.50). IPFTs in NEHI subjects are feasible, demonstrate significant obstruction and air trapping, and correlate with future RA O2 sat and FEV1 . IPFTs may provide valuable clinical information when caring for NEHI patients. Pediatr Pulmonol. 2013; 48:1008-1015. © 2012 Wiley Periodicals, Inc.

New reference equations to improve interpretation of infant lung function

With increasing use of infant pulmonary function tests (IPFTs) in both clinical and research studies, appropriate interpretation of results is essential. To investigate the potential bias associated with "normalising" IPF by expressing results as a ratio of body size and to develop reference ranges for tidal breathing parameters, passive respiratory mechanics (compliance [Crs] and resistance [Rrs]) and plethysmographic functional residual capacity (FRCp ) for white infants during the first 2 years of life. IPFTs were measured using the Jaeger BabyBody system and standardized protocols. Reference equations, adjusted for body size, age, and sex where appropriate, were created using multilevel modeling. The ratio of lung function to body length changes markedly with growth, thereby precluding its use for any outcome. While the ratio of tidal volume and Crs to body weight remained relatively constant with growth, this was not the case for FRCp . Even in healthy infants, a strong inverse relationship was observed between lung function/body weight and weight z-score which could distort interpretation of results in growth-restricted infants with lung disease, such as cystic fibrosis. Reference equations were derived from 153 healthy white infants on 232 test occasions (median age 35.5 weeks [range: 2.6-104.7]). Crown-heel length was the strongest predictor of IPF. When reporting IPF, use of size-corrected ratios should be discouraged, with interpretation instead based on appropriate reference equations. The current equations are applicable to white infants and young children up to 2 years of age, studied using the same commercially available equipment. The extent to which these equations are applicable to infants and young children of other ethnic backgrounds or who are tested with different equipment needs to be established.

Inhaled Hypertonic Saline in Infants and Children Younger Than 6 Years With Cystic Fibrosis

Inhaled hypertonic saline is recommended as therapy for patients 6 years or older with cystic fibrosis (CF), but its efficacy has never been evaluated in patients younger than 6 years with CF.To determine if hypertonic saline reduces the rate of protocol-defined pulmonary exacerbations in patients younger than 6 years with CF.The Infant Study of Inhaled Saline in Cystic Fibrosis (ISIS), a multicenter, randomized, double-blind, placebo-controlled trial conducted from April 2009 to October 2011 at 30 CF care centers in the United States and Canada. Participants were aged 4 to 60 months and had an established diagnosis of CF. A total of 344 patients were assessed for eligibility; 321 participants were randomized; 29 (9%) withdrew prematurely.The active treatment group (n = 158) received 7% hypertonic saline and the control group (n = 163) received 0.9% isotonic saline, nebulized twice daily for 48 weeks. Both groups received albuterol or levalbuterol prior to each study drug dose.Rate during the 48-week treatment period of protocol-defined pulmonary exacerbations treated with oral, inhaled, or intravenous antibiotics.The mean pulmonary exacerbation rate (events per person-year) was 2.3 (95% CI, 2.0-2.5) in the active treatment group and 2.3 (95% CI, 2.1-2.6) in the control group; the adjusted rate ratio was 0.98 (95% CI, 0.84-1.15). Among participants with pulmonary exacerbations, the mean number of total antibiotic treatment days for a pulmonary exacerbation was 60 (95% CI, 49-70) in the active treatment group and 52 (95% CI, 43-61) in the control group. There was no significant difference in secondary end points including height, weight, respiratory rate, oxygen saturation, cough, or respiratory symptom scores. Infant pulmonary function testing performed as an exploratory outcome in a subgroup (n = 73, with acceptable measurements at 2 visits in 45 participants) did not demonstrate significant differences between groups except for the mean change in forced expiratory volume in 0.5 seconds, which was 38 mL (95% CI, 1-76) greater in the active treatment group. Adherence determined by returned study drug ampoules was at least 75% in each group. Adverse event profiles were also similar, with the most common adverse event of moderate or severe severity in each group being cough (39% of active treatment group, 38% of control group).Among infants and children younger than 6 years with cystic fibrosis, the use of inhaled hypertonic saline compared with isotonic saline did not reduce the rate of pulmonary exacerbations over the course of 48 weeks of treatment.clinicaltrials.gov Identifier: NCT00709280.

Lung function from infancy to preschool in a cohort of children with cystic fibrosis

This study aimed to describe lung function in a cohort of children with cystic fibrosis (CF) who underwent infant pulmonary function tests (IPFTs) and preschool spirometry. Children performed up to four IPFTs (raised volume rapid thoracic compression technique) over 1 yr and five preschool spirometry tests over up to 2 yrs during participation in prospective, multicentre studies of infant and preschool lung function. All lung function data were reviewed centrally for measurement acceptability. 45 children had 252 acceptable measurements (137 IPFTs and 115 preschool spirometries) at ages 0.3-6.5 yrs. The median number of measurements per participant was 6 (range 3-9). Recent Pseudomonas aeruginosa infection was associated with 5.1% (95% CI 0.01-9.9%) lower forced expiratory volume in 0.5 s (FEV(0.5)) and 16.4% (95% CI 7.0-24.9%) lower forced expiratory flow at 25-25% of forced vital capacity (FEF(25-75%)), after adjustment for length, test type and centre. Recent cough was associated with 5.7% (95% CI 1.1-10.1%) lower FEV(0.5) and 10.1% (95% CI 0.6-18.7%) lower FEF(25-75%). Even after accounting for infection status, cough, sex, length, test type and centre, there was significant inter-individual variability in lung function (p<0.01 for each of FEV(0.5), FEF(25-75%) and forced vital capacity). Recent P. aeruginosa infection and cough are associated with lower lung function in children with CF. Significant inter-individual variability in lung function remains to be explained.

Exhaled breath condensate purines correlate with lung function in infants and preschoolers

Although airway inflammation begins early in life in children with chronic respiratory diseases, current methods to assess this inflammation are invasive and entail significant risk. Measurement of exhaled breath condensate (EBC) purines and other biomarkers offers a less invasive method to assess airway inflammation; however, the feasibility and utility of EBC biomarkers in young children has not been established. EBC was collected from children <3 years old with cystic fibrosis or other lung diseases during clinically indicated infant pulmonary function tests (iPFTs). EBC concentrations of the purine biomarkers adenosine (Ado), adenosine monophosphate (AMP), and the dilution marker urea were measured using mass spectrometry. EBC was successfully collected (average volume 330 ± 170 µl) from preschool children (age 2.3 ± 0.8 years) in 15 of 17 iPFTs. No significant changes in oxygen saturation (96.9 ± 1.6 start, 96.8 ± 1.7 end, P = 0.389) or respiratory rate (35.2 ± 7.5 start, 34.6 ± 7.9 end, P = 0.443) were observed during collection. Ado and AMP were successfully measured in 13/15 samples [8 cystic fibrosis (CF)]. EBC AMP to Ado ratio (AMP/Ado) negatively correlated with forced expiratory volume at 0.5 sec (FEV(0.5) , r = -0.71, P < 0.01) and positively with the ratio of residual volume to total lung capacity (RV/TLC, r = 0.66, P = 0.015). These correlations remained statistically significant in the subset with CF. EBC can be safely collected and analyzed in preschool children using commercially available equipment. The EBC AMP/Ado ratio correlates with measures of infant lung function and may be a less invasive means of monitoring airway inflammation in this population.

Improvement in pulmonary function following antibiotics in infants with cystic fibrosis

Recent studies have shown the presence of lung disease in even asymptomatic infants with cystic fibrosis (CF). While pulmonary function testing (PFT) is often used to follow progression of lung disease and guide treatment in older children with CF, little data is available on change in infant PFTs in young children with CF. To determine change in infant PFTs before and after antibiotic therapy for pulmonary exacerbation in infants with CF. Retrospective cohort study of infants with CF who underwent clinically indicated infant PFTs before and after antibiotic therapy for CF pulmonary exacerbation at the University of North Carolina at Chapel Hill. Pre- and post-antibiotics PFT data was available on 11 infants with CF, with a mean age of 102 weeks at time of first PFT. The majority of infants were symptomatic prior to antibiotics, and showed statistically significant improvement in clinical parameters following treatment. Prior to antibiotics, PFTs showed evidence of substantial obstructive disease (mean z-scores for FVC, FEV(0.5) , and FEF(25-75) of -1.81, -3.06, and -4.5, respectively) and air-trapping/hyperinflation (mean z-scores for FRCpleth, RV, and RV/TLC of 8.86, 7.1, and 3.31, respectively). Following antibiotics, all of the above parameters showed statistically significant improvement. We have shown a statistically significant improvement in infant PFT measures following antibiotic therapy in a cohort of 11 infants with CF, which paralleled improvement in clinical parameters. Though infant PFTs showed improvement, they remained abnormal in the majority of subjects, with persistent air-trapping and hyperinflation after antibiotic therapy. Our findings suggest that infant PFTs are sensitive to acute clinical changes in children with CF, and may be a useful tool in managing infants with CF.

195 Pulmonary function in cystic fibrosis children younger than 3 years old

Studies suggest that the decline in pulmonary function begins early in CF infants even in those patients without respiratory symptoms. Objective: to describe pulmonary function in CF children younger than 3 years old and to determine if there is any association between pulmonary function and clinical features. Methods: observational and retrospective, study. We collected data from CF patients who underwent an Infant Pulmonary Function Test (IPFT) before the age of three years. IPFTs were assessed by partial flow/volume curves with the rapid thoracicabdominal compression technique to obtain the maximal flow at the functional residual capacity (V′maxFRC). Clinical issues recorded were: age, gender, genetics, pancreatic sufficiency, nutritional status and microbiological findings. Results: 46 patients (31 males) with a median (interquartile range) age of 8 months (5 to 15) were included. Overall V′maxFRC Z score was −0.8 (−1.4 to 0.3), −0.1 (−1.1 to 0.7) in males and −0.9 (−1.8 to 0.3) in females (p =NS). V′maxFRC Z score was −0.3 (−1.1 to 0.2) in children younger than 6 months and −0.1 (−1.3 to 1) in older ones (p =NS). In patients homozygous p.508del V′maxFRC Z score was −0.5 (−1.2 to 0.8) while in patients with other mutations it was −0.2 (−1.2 to 0.6) (p =NS). There was also no statistical difference in V′maxFRC between well-nourished and bad-nourished patients, and between patients with and without Pseudomonas aeruginosa (PA) in sputum. Conclusion: IPFT assessed by partial flow/volume curves was normal in our CF population less than 3 years old. We have not found any difference in pulmonary function comparing CF children with different clinical features.

196 FEV 1 decline in cystic fibrosis (CF): much attention should be devoted to children and adolescents

Studies suggest that the decline in pulmonary function begins early in CF infants even in those patients without respiratory symptoms. Objective: to describe pulmonary function in CF children younger than 3 years old and to determine if there is any association between pulmonary function and clinical features. Methods: observational and retrospective, study. We collected data from CF patients who underwent an Infant Pulmonary Function Test (IPFT) before the age of three years. IPFTs were assessed by partial flow/volume curves with the rapid thoracicabdominal compression technique to obtain the maximal flow at the functional residual capacity (V′maxFRC). Clinical issues recorded were: age, gender, genetics, pancreatic sufficiency, nutritional status and microbiological findings. Results: 46 patients (31 males) with a median (interquartile range) age of 8 months (5 to 15) were included. Overall V′maxFRC Z score was −0.8 (−1.4 to 0.3), −0.1 (−1.1 to 0.7) in males and −0.9 (−1.8 to 0.3) in females (p =NS). V′maxFRC Z score was −0.3 (−1.1 to 0.2) in children younger than 6 months and −0.1 (−1.3 to 1) in older ones (p =NS). In patients homozygous p.508del V′maxFRC Z score was −0.5 (−1.2 to 0.8) while in patients with other mutations it was −0.2 (−1.2 to 0.6) (p =NS). There was also no statistical difference in V′maxFRC between well-nourished and bad-nourished patients, and between patients with and without Pseudomonas aeruginosa (PA) in sputum. Conclusion: IPFT assessed by partial flow/volume curves was normal in our CF population less than 3 years old. We have not found any difference in pulmonary function comparing CF children with different clinical features.

Infant Pulmonary Function Testing: Overview of Technology and Practical Considerations—New Current Procedural Terminology Codes Effective 2010

Infant pulmonary function testing has evolved from a research technique into a diagnostic tool. As such, new current procedural terminology (CPT) codes have been created and are available for use as of January 1, 2010. The technology now available has a range of applications. Through a series of vignettes, this article illustrates the methodology of the tests, some of their applications, and how to code and bill for the procedures.

Neuroendocrine Cell Distribution and Frequency Distinguish Neuroendocrine Cell Hyperplasia of Infancy From Other Pulmonary Disorders

The diagnostic gold standard for neuroendocrine cell hyperplasia of infancy (NEHI) is demonstration of increased numbers of neuroendocrine cells (NECs) amid otherwise near-normal lung histology. Typical clinical and radiographic features often are present. However, NECs are also increased after lung injury and in other disorders, which can complicate biopsy specimen interpretation and diagnosis of suspected NEHI. Our objective was to determine whether NEC prominence is specific for the diagnosis of NEHI. Bombesin immunoreactivity was quantified in lung biopsy specimens from 13 children with characteristic clinical presentation and imaging appearance of NEHI. The primary comparison group was 13 age-matched patients selected from children with lung disorders that are known to be associated with NEC prominence. Bombesin-immunopositive epithelial area was significantly increased in NEHI compared with other diseases. Patchy bronchiolar inflammation or fibrosis was frequently observed in NEHI, with no direct association between airway histopathology and bombesin-immunopositive area. NEC prominence correlated with severity of small airway obstruction demonstrated on infant pulmonary function testing. Immunohistochemical colocalization of bombesin with Ki67 did not reveal active NEC proliferation. There was wide intra- and intersubject variability in NEC number, which did not relate to radiographic appearance of the region biopsied. Our findings demonstrate that NEC prominence is a distinguishing feature of NEHI independent of airway injury. The extent of intrasubject variability and potential for overlap with control subjects suggest that clinical-radiologic-pathologic correlation is required for diagnosis and that the abundance of NECs may not fully explain the disease pathogenesis.

Infant Pulmonary Function Testing: Overview of Technology and Practical Considerations—New Current Procedural Terminology Codes Effective 2010

Infant Pulmonary Function Testing: Overview of Technology and Practical Considerations—New Current Procedural Terminology Codes Effective 2010

Multicenter Evaluation of Infant Lung Function Tests as Cystic Fibrosis Clinical Trial Endpoints

The conducting of clinical trials in infants with cystic fibrosis (CF) has been hindered by lack of sensitive outcome measures. To evaluate safety, feasibility, and ability to detect abnormalities in lung function of serial pulmonary function tests (PFTs) in infants with CF. Multicenter observational study using a commercial device, rigorous training, ongoing quality control, and over-reading of data by an independent panel. Raised volume rapid thoracoabdominal compression technique and plethysmography were performed at enrollment and at 6 and 12 months, with an additional 1-month reproducibility visit. A total of 342 procedures were performed in 100 infants with CF at 10 centers. FRC measurements were acceptable at a higher proportion of study visits (89%) than raised volume (72%) or fractional lung volume (68%) measurements. Average Z scores for many parameters differed significantly from historical control values. Mean (95% confidence interval) Z scores were: -0.52 (-0.78 to -0.25) for forced expiratory flow at 75% (FEF₇₅) for FVC; 1.92 (1.39-2.45) for FRC; 1.22 (0.68-1.76) for residual volume; 0.87 (0.60-1.13) for FRC/total lung capacity; and 0.66 (0.27-1.06) for residual volume/total lung capacity. For future multicenter clinical trials using infant PFTs as primary endpoints, minimum detectable treatment effects are presented for several sample sizes. In this 10-center study, key PFT measures were significantly different in infants with CF than in historical control subjects. However, infant PFTs do not yet appear ready as primary efficacy endpoints for multicenter clinical trials, particularly at inexperienced sites, based on acceptability rates, variability, and potentially large sample sizes required to detect reasonable treatment effects.

Infant pulmonary function testing guides therapy in cystic fibrosis lung disease

Longitudinal measures of pulmonary function are a fundamental part of care for older children and adults with cystic fibrosis. The dilemma for the clinician caring for infants with cystic fibrosis is how to best objectively assess and treat early lung disease to maintain good lung health for as long as possible. In this report, we present two cases where infant pulmonary function testing revealed an unexpected degree of airway pathology that altered our clinical decision making. Following treatment with intravenous antibiotics, infant pulmonary function tests demonstrated dramatic improvement. These cases demonstrate the utility of infant pulmonary function testing in guiding the management of infants with cystic fibrosis.

2010 Medicare Resource-Based Relative Value Scale: Good and Bad News

Newly accepted work RVUs for H1N1, practice expense transition over 4 years, and new codes for infant pulmonary function testing; elimination of office outpatient/inpatient consultation codes, echocardiography codes, moderate sedation