Time Of Pulmonary Function Testing Research Articles

Longitudinal Analysis of Pulmonary Function in Survivors of Congenital Diaphragmatic Hernia

Background: Due to studies with small sample size and short follow-up duration, there is limited information on the natural history of lung function in survivors of congenital diaphragmatic hernia (CDH). In this study, we determined the trends over time of pulmonary function test (PFT) in CDH patients followed at our multidisciplinary clinic. Methods: This is a retrospective cohort study of CDH patients born between 1991 and 2013. Demographic and baseline variables were compared between those who had only one …

Assessment of pulmonary function test abnormalities in adult survivors of childhood cancer.

117 Background: As childhood cancer survival approaches 85%, it is increasingly recognized that childhood cancer survivors (CCS) are at risk for long-term therapy-related complications. Data suggest that pulmonary function test (PFT) abnormalities occur in as many as 84.1% of CCS. Our aim was to assess the prevalence and nature of respiratory abnormalities in adult CCS and to correlate these abnormalities with therapeutic exposures and health behaviors. Methods: Patients who received pulmonary toxic therapy routinely undergo PFTs at their first visit to the POGO AfterCare clinic in Ottawa, Canada. We conducted a retrospective review of all patients seen in clinic from August 2015 until December 2016. PFT results, treatment exposures and health habits were documented. We used NHANES-III prediction equations for PFT interpretation, with expiratory flows and lung volumes of ≥80% predicted as cutoffs for normal. Results: Of a total of 200 patients, 48 received pulmonary toxic therapy and 38 underwent PFTs. Mean age at the time of PFT was 28.8 years (18.5-57.5 years) and the mean time from diagnosis was 17.4 years (3.4-47.5 years). Although no patients reported respiratory symptoms, 42% (16/38) demonstrated a mild restrictive ventilatory defect, 11% (4/38) had mild airflow obstruction, 18% (7/38) had an isolated reduction in diffusion capacity and 1 patient had a moderate mixed obstructive/restrictive abnormality. Only 26% (10/38) had normal lung function. Of those with restrictive defects, all received radiation and 50% were also exposed to pulmonary toxic chemotherapy. All patients with obstructive defects received radiation therapy in combination with bleomycin. Tobacco or marijuana use was reported in 26% (10/38) of the cohort, and in 29% (8/28) of those with PFT abnormalities. Conclusions: PFT abnormalities are common among adult CCS who received pulmonary toxic therapy. Studies evaluating the change in pulmonary function abnormalities over time and their correlation to cardiopulmonary exercise testing and lung imaging are required to inform the health impact on these survivors.

Pulmonary function and outcomes in infants randomized to a rescue course of antenatal steroids

Our objective was to obtain follow-up pulmonary function testing and assessment of clinical respiratory outcomes, at 1-2 years, in preterm infants whose mothers were randomized to a single rescue course of antenatal steroids (AS) versus placebo. Follow-up of a randomized, double-blinded trial. In the original trial pregnant women ≥14 days after initial course of AS were randomized to rescue AS or placebo. Pulmonary function testing and a standardized respiratory questionnaire were obtained at 1-2 years of corrected age. Respiratory compliance (Crs) was measured with the single-breath occlusion and functional residual capacity (FRC) with the nitrogen washout method. Analysis was by intention-to-treat. A total of 96 (87%) of available survivors were administered a respiratory questionnaire. Seventy-seven percent of available patients had pulmonary function testing performed. There was no significant difference between groups in incidence of wheezing, asthma, respiratory syncytial virus infection, respiratory readmissions, use of bronchodilators or other medications, or in measurements of pulmonary function. There was also no significant difference in corrected age at study, race, gender, or length at the time of pulmonary function testing. Infants in the rescue group had a comparable mean FRC (249.4 mL vs 246.2 mL; adjusted 95%CI for difference -15.45, 38.20; P = 0.37) versus placebo. There were no differences in tidal volume or Crs. A rescue course of AS significantly increases Crs within 72 h of age and decreases oxygen need in newborn infants, without an adverse impact on pulmonary function or clinical respiratory outcomes at 1-2 years of age [NCT00669383].

Pulmonary Function Tests in Idiopathic Inflammatory Myopathy: Association With Clinical Parameters in Children

To determine the association of decreased lung function in children with idiopathic inflammatory myopathies (IIMs) with specific clinical parameters. This study of 38 children ages 6-23 years diagnosed with definite/probable IIM evaluated the association of myositis-specific/-associated antibodies (MSAs/MAAs), duration of untreated disease at diagnosis, Disease Activity Score for muscle (DAS-M), muscle-derived enzymes (aldolase, lactate dehydrogenase [LDH], aspartate transaminase, and creatine phosphokinase [CPK]), neopterin and von Willebrand factor antigen, and the Childhood Myositis Assessment Scale (CMAS) scores with data from pulmonary function testing (PFT). Impaired PFTs were defined as total lung capacity (TLC) or diffusing capacity for carbon monoxide (DLCO) of <80% predicted. The PFTs documented that 37% of the children (14 of 38) had either decreased TLC or decreased DLCO; 5% (2 of 38) had both. Children with decreased TLC alone (7 [18%] of 38) were older both at the time of PFT and diagnosis, had anti-Jo-1 and anti-Scl-70 antibody, and had elevated levels of CPK and neopterin. Children with decreased DLCO alone (5 [13%] of 38) had a shorter duration of untreated disease at diagnosis, had higher DAS-M and total DAS, were positive for anti-Ro and anti-PL-12, had increased LDH, and had elevated levels of neopterin and aldolase, with low CMAS scores for items 1, 3, 10, 11, and 14. Assessment of PFTs in children with IIMs should be considered, since more than one-third of patients were found to be impaired. The presence of MSAs/MAAs, an elevated serum neopterin level (mean ± SD 12.4 ± 9.6 nmoles/liter, normal value <10.5), older age at diagnosis, and shorter duration of untreated disease at diagnosis suggest the presence of potential lung pathology.

The Prevalence of Alpha-1 Antitrypsin Deficiency Among Patients Found to Have Airflow Obstruction

Introduction: Alpha-1 antitrypsin deficiency (AATD) is a genetic disease that may be manifested by chronic obstructive pulmonary disease. Despite professional society guidelines that recommend broad testing of at-risk individuals, fewer than 10% of affected individuals have been identified. The goals of this study were to estimate the frequency of abnormal AAT genotypes among patients found to have fixed airflow obstruction and to assess the feasibility of having Pulmonary Function Laboratory personnel administer the study. Methods: Nineteen medical centers in the United States participated in the study. Eligible patients (> GOLD II, FEV1/FVC ratio < 0.7, with post-bronchodilator FEV1<80% predicted) were offered testing for AATD by the Pulmonary Function Laboratory personnel at the time of pulmonary function testing. Results: A total of 3,457 patients were tested, of whom 3152 were eligible. Deficient patients (ZZ, SZ) constituted 0.63% of subjects, while 10.88% were carriers (MS, MZ). Neither demographic (except African-American race) nor post-bronchodilator pulmonary function variables (FEV1, FVC, FEV1/FVC ratio, TLC, and FEV1/FVC) allowed us to predict AAT heterozygote or deficiency status. Conclusions: The prevalence of AATD among patients undergoing pulmonary function tests with fixed airflow obstruction was 0.63%. Pulmonary Function Laboratory personnel effectively conducted the study.

Impaired carbon monoxide diffusing capacity as a marker of limited systemic sclerosis

Background As impairment of diffusing capacity for carbon monoxide (DLCO) likely reflects underlying pulmonary vasculopathy in limited systemic sclerosis (lSSc), we examined whether DLCO could help to distinguish secondary from idiopathic Raynaud's phenomenon (iRP). Methods We compared pulmonary function test (PFT) results in 145 lSSc patients and 24 age- and sex-matched iRP patients. RP duration at time of PFT was similar in the two groups. Results DLCO values were low (< 80% of predicted) in 106 (73%) of the 145 lSSc patients, and in 69 (71%) of the 97 patients with early lSSc. Interstitial lung disease (ILD) was found in 10% of lSSc patients. DLCO was significantly lower in lSSc than in iRP (72 ± 15% versus 89 ± 9%, p < 0.0001). When evaluated, alveolar capillary membrane conductance (Dm) was markedly lower in lSSc patients without ILD than in iRP patients (45 ± 12% versus 71 ± 2.5%, p = 0.003), although capillary blood volume was not different. DLCO was low in 3 iRP patients (12.5%). The sensitivity and specificity of low DLCO values for early lSSc diagnosis in patients with Raynaud's phenomenon were 71% and 87.5%, respectively. Sensitivity was similar to that of anti-centromere-antibodies (75%) and nailfold capillary abnormalities (81%). A DLCO cutoff of < 70% had a sensitivity and specificity of 41% and 100%, respectively. In multivariable analysis, age and low DLCO were the only independent predictors of death; the hazard ratio for DLCO ≤ 50% was 7.9 (95% CI 2.3–26, p = 0.0007). Conclusion Isolated DLCO impairment is significantly more frequent in patients with lSSc than in patients with idiopathic iRP. DLCO measurement could be a useful diagnostic tool for lSSc.

Pulmonary function in children treated for rhabdomyosarcoma.

Chemotherapy, radiation therapy, and surgical intervention have markedly improved the survival of patients treated for rhabdomyosarcoma. Unfortunately, the therapy may have deleterious effects on the lung. Pulmonary functions tests were obtained from 17 patients treated for rhabdomyosarcoma because of our concern regarding potential pulmonary dysfunction in this group of patients who had received bleomycin, which is known to be associated with lung injury. Mean age at the time of the diagnosis of rhabdomyosarcoma was 10.1 (+/- 7.2) years (range 0.01-23.5 years). The mean age at the time of pulmonary function testing was 17.0 (+/- 7.5) years (range 5.8-34.0 years). Study patients reportedly had no pulmonary symptoms. Approximately 87% of study patients had a restrictive ventilatory impairment on pulmonary function testing as measured by total lung capacity (TLC) values less than the lower limit of normal. Approximately 70% of study patients had carbon monoxide diffusing capacity (DLCO) values less than the lower limit of normal. There were no significant differences in pulmonary function parameters when male study patients were compared to female study patients. There was a statistically significant lower forced expiratory volume in 1 second/forced vital capacity (FEV1/FVC) ratio (P=0.03) and percent predicted forced expiratory flow at 25-75% of the FVC (FEF25-75; P=0.03) in the group of patients diagnosed with rhabdomyosarcoma over 8 years of age as compared to those individuals diagnosed under 8 years of age. In addition, there were no statistically significant differences in pulmonary function when the variables of sex and age at diagnosis (as outlined above) were studied in combination. In summary, we identified a high incidence of restrictive ventilatory abnormalities in a group of individuals (predominantly children) treated for rhabdomyosarcoma as well as a significantly lower FEV1/FVC ratio and percent predicted FEF25-75 in the group of patients diagnosed with the neoplasm over 8 years of age. Individuals caring for such patients are encouraged to obtain pre- and sequential posttreatment pulmonary function tests.

The Effect of Maternal Smoking during Pregnancy on Early Infant Lung Function

We studied the effect of prenatal maternal cigarette smoking on the pulmonary function (PF) of 80 healthy infants tested shortly after birth (mean, 4.2 +/- 1.9 wk). Mothers' prenatal smoking was measured by: (1) questionnaire reports at each prenatal visit of the number of cigarettes smoked per day, and (2) urine cotinine concentrations (corrected for creatinine) obtained at each visit. Infant PF was assessed by partial expiratory flow-volume curves and helium-dilution measurement of FRC. Forced expiratory flow rates were significantly lower in infants born to smoking mothers, both when unadjusted and after controlling for infant size, age, sex, and passive exposure to environmental tobacco smoke (ETS) between birth and the time of PF testing. Flow at functional residual capacity (VFRC) in infants born to smoking mothers was lower than that found in infants whose mothers did not smoke during pregnancy (74.3 +/- 15.9 versus 150.4 +/- 8.9 ml/s; p = 0.0007). Differences remained significant when flow was corrected for lung size (VFRC/FRC: 0.87 +/- 0.26 versus 1.77 +/- 0.12 s-1; p = 0.013). No differences in pulmonary function were evident among infants exposed and unexposed to ETS in the home after stratifying by prenatal exposure status. We conclude that maternal smoking during pregnancy is associated with significant reductions in forced expiratory flow rates in young infants. The results suggest that maternal smoking during pregnancy may impair in utero airway development and/or alter lung elastic properties. We speculate that these effects of maternal prenatal smoking on early levels of forced expiratory flow may be an important factor predisposing infants to the occurrence of wheezing illness later in childhood.

Birthweight, early passive respiratory system mechanics, and ventilator requirements as predictors of outcome in premature infants with respiratory failure

Early respiratory mechanics have been reported to predict outcome in newborns with respiratory failure. However, it remains unknown whether measurements of pulmonary function add significantly to the predictive value of more readily available variables The present study was designed to answer this question. Passive respiratory system mechanics were measured by an airway occlusion technique in 104 ventilator-dependent premature infants between 6 and 48 hours of life and corrected for infant size. A ventilation index [FiO2 x mean airway pressure (MAP)] was calculated at the time of pulmonary function testing. Poor outcome was defined as death from respiratory failure or need for supplemental oxygen at 28 days. Stepwise logistic function regression examined whether ventilation index and respiratory mechanics added predictive power over and above birthweight. Five infants died, and 45 patients required supplemental oxygen at 28 days. Birthweight was a strong predictor and would have entered the logistic model first in any case. Ventilation index added significantly to the predictive model (P = 0.038). Respiratory system conductance (P = 0.15) and compliance (P = 0.93) entered on the third and last step, respectively. We conclude that in premature infants with respiratory failure, birthweight is a strong predictor of outcome. Early ventilator requirements but not respiratory system mechanics, add significantly to this predictive model.