The prognosis for patients with cystic fibrosis who are colonised with Pseudomonas aeruginosa has improved as a result of the regular use of intravenous antibiotics; however, this necessitates long periods of hospitalisation. Home intravenous antibiotic treatment has potential advantages over hospital treatment. We describe our experience during the first 20 months of using a system of home intravenous antibiotic treatment in which a cystic fibrosis liaison sister has an essential role. Thirteen patients have received 40 courses of treatment. There were highly significant improvements in weight, respiratory function, and white cell count during home treatment. There was no significant difference in weight and forced expiratory volume in one second between the end of home treatment and the end of hospital treatment while forced vital capacity was better after home treatment. All patients preferred home treatment. The advantages of home visits by the cystic fibrosis liaison sister during treatment are emphasised.
Rationale: Individuals with cystic fibrosis (CF) are subject to recurrent respiratory infections (exacerbations) that often require intravenous antibiotic treatment and may result in permanent loss of lung function. The optimal means of delivering therapy remains unclear.
Objectives: To determine whether duration or venue of intravenous antibiotic administration affect lung function.
Methods: Data were retrospectively collected on 1,535 subjects recruited by the US CF Twin and Sibling Study from US CF care centers between 2000 and 2007.
Measurements and Main Results: Long-term decline in FEV1 after exacerbation was observed regardless of whether antibiotics were administered in the hospital (mean, −3.3 percentage points [95% confidence interval, −3.9 to −2.6]; n = 602 courses of therapy) or at home (mean, −3.5 percentage points [95% confidence interval, −4.5 to −2.5]; n = 232 courses of therapy); this decline was not different by venue using t tests (P = 0.69) or regression (P = 0.91). No difference in intervals between courses of antibiotics was observed between hospital (median, 119 d [interquartile range, 166]; n = 602) and home (median, 98 d [interquartile range, 155]; n = 232) (P = 0.29). Patients with greater drops in FEV1 with exacerbations had worse long-term decline even if lung function initially recovered with treatment (P < 0.001). Examination of FEV1 measures obtained during treatment for exacerbations indicated that improvement in FEV1 plateaus after 7–10 days of therapy.
Conclusions: Intravenous antibiotic therapy for CF respiratory exacerbations administered in the hospital and in the home was found to be equivalent in terms of long-term FEV1 change and interval between courses of antibiotics. Optimal duration of therapy (7–10 d) may be shorter than current practice. Large prospective studies are needed to answer these essential questions for CF respiratory management.
cystic fibrosis; FEV1; exacerbation; antibiotic; outcome
Sleep related arterial oxygen desaturation has been described in clinically stable young adults with cystic fibrosis. The incidence and severity of nocturnal oxygen desaturation in children during infective exacerbations and the changes that occur with treatment were examined. Forty five children with proved cystic fibrosis, median age 8.9 years, admitted to the Regional Cystic Fibrosis Unit underwent clinical evaluation, spirometry, and measurement of peak flow and nocturnal oxygen saturation on admission and after 10 days' treatment. There was a significant improvement in all the above measurements, with the averaged overnight saturation changing from a mean (SD) 92.7 (2.7)% to 94.3 (2.0)%, mean (SE) difference 1.58 (0.37). The time spent with a saturation 4% or more below their clinic value showed a marked improvement from 122 (152) minutes on the first night to 21 (30.7) on the second, mean (SE) difference 101 (22.4). Eight young children could not perform pulmonary function tests, all desaturated on the admission night. Nocturnal hypoxaemia is a common finding in young cystic fibrosis patients during infective exacerbations but improves with treatment. Overnight oximetry is simple to perform, well tolerated, and identifies patients with marked nocturnal desaturation.
Twelve children with cystic fibrosis were admitted to a paediatric rehabilitation hospital for 17 days to take part in a training programme of vigorous physical exercise and sport. The daily inhalation-physiotherapy routine was stopped. Ventilatory status was assessed by spirometry and measurement of lung volumes one day before admission, one day after the end of the hospital stay, and 8 weeks later. Flow measurements of forced expiration had improved appreciably by the end of the course, but most of them returned to pretraining levels 8 weeks later. Lung volumes did not change significantly. Daily recordings of peak flow indicated improvement of airways function plus some ventilatory muscle training. Regular physical exercise could replace the inhalation-physiotherapy routine in some children with cystic fibrosis.
Fourteen (29%) of 48 children with cystic fibrosis had a greater than 15% improvement in forced expiratory volume in one second, or in forced vital capacity after inhalation of salbutamol. All these children were atopic (one or more positive prick tests) and had a significantly higher mean serum IgE than either non-atopic subjects or those atopic subjects without airways reversibility (p less than 0.02). Half of those with airways reversibility had or subsequently developed the clinical picture of allergic bronchopulmonary aspergillosis. Of the whole group 81% were atopic, of whom 77% had a positive reaction to A fumigatus, 64% to housedust, and 56% each to grass pollen and cat hair. Children who were not atopic had significantly better spirometry (p greater than 0.05) than those who were. Children with skin hypersensitivity to A fumigatus had identical spirometry to those who were atopic without reactivity to A fumigatus. Serum precipitins to A fumigatus were present in 48%. Serum precipitins to pancreatin were present in 71%, but the presence of these precipitins did not correlate with atopy, airways reversibility, or serum IgE.
Twenty patients with inoperable carcinoma in the trachea or a main bronchus were investigated before and one and 10 days after treatment with a carbon dioxide laser. Patients were assessed by spirometry, maximum flow-volume loops, and a visual analogue score of breathlessness on a scale from 0 (not at all breathless) to 100 (very breathless). At day 10 mean FEV1 had improved from 51.9% to 62.6% of predicted (p less than 0.02) and mean peak expiratory flow (PEF) from 45.3% to 53.1% of the predicted value (p less than 0.05). Improvements in maximum inspiratory and expiratory flows at 50% vital capacity were not significant but the breathlessness score decreased from a mean of 49.1 to 35.3 (p less than 0.01). Improvements in breathlessness were significantly correlated with increases in FEV1 and PEF. Thirteen of the 20 patients had unilateral tumours with partial or complete occlusion of the main bronchus; in these perfusion and ventilation were assessed by radioisotope scans before and 10 days after treatment. Seven of the 13 patients showed an increase in perfusion of the affected lung after treatment but the improvement was small, with a mean increase in unilateral perfusion in the 13 patients of 2.4% of the total counts. Four patients with no perfusion of the affected side showed no significant improvement after laser treatment. Changes in ventilation scans were similar to those in perfusion. It is concluded that laser treatment improves airway function and dyspnoea in malignant narrowing of central airways and that in unilateral obstruction such treatment results, at best, in a small increase in the contribution of the affected lung to perfusion.
The Six-Minute-Walk Test (6-MWT) is an established and well-validated diagnostic procedure in cardiovascular and pulmonary diseases. The significance of the 6-MWT in the assessment of the respiratory function in tumor patients after lung surgery is yet unclear.
The retrospective study included 227 patients following oncological rehabilitation after lobectomy, pneumonectomy or wedge- and segmental resection due to a malignant tumor disease. Spirometry and 6-MWT were performed at the beginning (T1) and at the end (T2) of oncological rehabilitation and correlated with each other. A subgroup analysis on clinically relevant parameters was conducted as well.
A significant improvement of the walking distance measured in 6-MWT as well as of forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) were detected within the scope of spirometry (all three P<0.01). This effect was demonstrable in all subgroups, except for patients who underwent pneumonectomy. However, a low correlation of the parameters walking distance and FEV1 was observed at both measurement points T1 (rho value =0.21) and T2 (rho value =0.25).
Measuring the walking distance in the 6-MWT could be a suitable parameter to assess respiratory function.
Six-Minute-Walk Test (6-MWT); respiratory function; lung surgery; oncological; rehabilitation
The effects of a home care program with 102 courses (2336 patient-days) of intravenous antibiotic therapy were evaluated. Home care nurses changed the intravenous cannula site every 3 days. The initial hospital stay averaged 11.8 days and the duration of home therapy averaged 22.9 days. The diseases treated included osteomyelitis, septic arthritis, endocarditis, cystic fibrosis and pneumonia, staphylococcal bacteremia, blastomycosis, actinomycosis and other soft tissue infections. All classes of commonly used antibiotics, including penicillins, cephalosporins, aminoglycosides and amphotericin B, were administered, alone or in combination. There were no side effects that necessitated discontinuation of home treatment or readmission to hospital. The average cost per patient-day was $58, compared with an estimated $193 for in-hospital therapy; in addition, 2336 hospital bed-days were made available. Most patients were able to resume many or all of their daily activities while receiving intravenous antibiotic therapy.
There is a worldwide drive for the home management of chronic respiratory diseases. With the widespread use of home intravenous (IV) treatment for cystic fibrosis (CF) pulmonary exacerbations (PExs), evidence pointing to an inferior outcome of care for home-treated patients in comparison to hospital-treated patients is a cause of concern. Currently, patients who self-administer IV antibiotics at home are provided with equipment and instructions on the use of antibiotics. Policies vary; but in most UK centers, these patients are then followed up by the multidisciplinary team only on days 1, 7 and 14 of the treatment course. We aimed to review the current published literature in search for evidence for the value and the shortfalls of self-administered IV treatment at home for acute PExs in CF patients in comparison to conventional hospital treatment. We searched the electronic database system Medline for published papers regarding studies comparing home- and hospital-based IV antibiotic treatment for both adult and pediatric CF patients. Sixteen studies were identified and grouped into those that showed a similar outcome between home and hospital treatment and those that showed an inferior outcome for home management. Most studies were retrospective or inadequately powered to provide clear answers. Ideally, outcome of care for home treatment should be at least equal to outcome for hospital treatment. Extensive efforts should be made to standardize therapies preserving the advantages of home management and addressing the perceived reasons for an inferior outcome. Until further studies provide definitive answers, treatment at home should be reserved for adequately selected patients and individualized depending on the unique settings of each CF center and specific patients' requirements. There is great need for a prospective randomized controlled trial comparing home and hospital treatments in order to clarify this matter.
Cystic fibrosis; home; treatment
Some patients with chronic obstructive pulmonary disease (COPD) may benefit from oral steroid therapy. These steroid-responsive patients are diagnosed based on laboratory spirometry. We hypothesize that daily, home-based spirometry is a better tool.
Thirty patients with COPD underwent a single-blinded study, with a crossover design. They received 2 weeks of placebo followed by 2 weeks of prednisone therapy (40 mg/day). Laboratory spirometry was done at the beginning and end of the study and daily home-based spirometry was done twice a day.
Analysis of variance model was used. The variability of the median day-to-day forced expiratory volume in 1 s (FEV1) was 72.5 mL (25th percentile of 40 mL and 75th percentile of 130 mL). The daily FEV1 variation was 70 mL (25th percentile of 50 mL and 75th percentile of 100 mL). The overall laboratory FEV1 variability was larger after the steroid course (P < 0.001), but not clinically significant. The variability was not significant postplacebo treatment compared with the baseline values. For home-based spirometry, steroid treatment was not significantly different. The majority (97%) completed more than 80% of the measurements. Ninety percent of the performed tests were considered acceptable. Only 53% of the tests were considered accurate. Overall both laboratory and home-based measurements did not show significant association between airway responsiveness and dyspnea or exercise capacity.
Twice-daily home measurements of FEV1 might be better than the conventional approach to identify steroid responsive COPD patients. However, this finding was only statistically but not clinically significant. Therefore, we would not recommend this approach to identify COPD patients with steroid responsiveness.
COPD; corticosteroids; home spirometry; responsiveness; variability
Bronchodilator responses (BDR) are routinely used in the diagnosis and management of asthma; however, their acceptability and repeatability have not been evaluated using quality control criteria for preschool children.
To compare conventional spirometry with an impulse oscillometry system (IOS) in healthy and asthmatic preschool children.
Data from 30 asthmatic children and 29 controls (two to six years of age) who underwent IOS and spirometry before and after salbutamol administration were analyzed.
Stable asthmatic subjects significantly differed versus controls in their spirometry-assessed BDR (forced expiratory volume in 1 s [FEV1], forced vital capacity and forced expiratory flow at 25% to 75% of forced vital capacity) as well as their IOS-assessed BDR (respiratory resistance at 5 Hz [Rrs5], respiratory reactance at 5 Hz and area under the reactance curve). However, comparisons based on the area under the ROC curve for ΔFEV1 % initial versus ΔRrs5 % initial were 0.82 (95% CI 0.71 to 0.93) and 0.75 (95% CI 0.62 to 0.87), respectively. Moreover, the sensitivity and specificity for ΔFEV1 ≥9% were 0.53 and 0.93, respectively. Importantly, sensitivity increased to 0.63 when either ΔFEV1 ≥9% or ΔRrs5 ≥29% was considered as an additional criterion for the diagnosis of asthma.
The accuracy of asthma diagnosis in preschool children may be increased by combining spirometry with IOS when measuring BDR.
Asthma; Bronchodilator agents; Oscillometry; Preschool; Spirometry
The purpose of the study was to check the hypothesis that early wheezing as reported by mothers would be associated with reduced lung function in 4-year-olds. Study participants were recruited prenatally, as part of a prospective cohort study on the respiratory health of young children exposed to various ambient air pollutants. After delivery, infants were followed over four years and the interviewers visited participants at their home to record respiratory symptoms every three months in the child’s first two years of life and every 6 months in the third and fourth years. In the fourth year of follow-up, children were invited for standard lung function testing by spirometry quantified by FVC, FEV1 and FEV05 levels. Out of 258 children attending spirometry testing 139 performed at least two acceptable exhalation efforts. Cohort children with acceptable spirometric measurements did not differ with respect to wheezing experience and exposure characteristics from those without. The study shows that episodic wheeze was reported in 28.1% of 4-year-olds, 6.5% had transient wheeze and 4.3% had recurrent wheeze. There was an increased frequency of wheezing symptoms and their duration in transient and recurrent wheezers. Adjusted multivariable regression models for gender and height showed that children who reported more than 2 episodes of wheezing at any point over the follow-up had FVC values lower by 120.5 mL (p = 0.016) and FEV1 values lower by 98.3 mL (p = 0.034) compared to those who did not report any wheezing; children experiencing more than 10 wheezing days by age 4 showed FVC deficit of 87.4 mL (p = 0.034) and FEV1 values of 65.7 mL (p = 0.066) The ratios of FEV1/FVC% and FEV05/FVC% were neither associated with wheezing episodes nor wheezing days. In recurrent wheezers lung function decrement amounted to 207 mL of FVC, 175 mL of FEV1 and 104 mL of FEV05. In conclusion, our findings show that wheezing experience during early postnatal life may be associated with lung function deficit of restrictive character in preschool children and detailed history of wheeze in early postnatal life, even though not physician-confirmed, may help define the high risk group of children for poor lung function testing.
Postoperative pain may be a significant reason for delayed discharge from hospital, increased morbidity and reduced patient satisfaction with ambulatory hernia surgery. This study compared two postoperative oral analgesic protocols after day case inguinal hernia repair; 30 mg morphine sulphate (MST) and 10 mg metoclopramide every 8 h for 48 h or 75 mg diclofenac twice daily for 48 h. The pain reported in the MST group was significantly greater on both the day of operation and the first postoperative day (P < 0.05, Mann-Whitney U test). A significantly higher proportion of patients taking MST complained of nausea on the day of operation and on the 1st postoperative day (P < 0.05, chi 2). The time taken to walk, dress and leave home alone were achieved in a significantly shorter duration in patients taking diclofenac. We conclude that diclofenac provides effective analgesia, has a more acceptable side-effect profile than morphine sulphate and is the treatment of choice after ambulatory hernia surgery.
One hundred and eight patients with cystic fibrosis were investigated over one year to determine whether an association existed between rhinovirus or other respiratory virus infection and clinical status. Forced expiratory volume in one second (FEV1), forced vital capacity (FVC), Shwachman score, Chrispin-Norman chest radiograph score, and percentage weight for height were recorded at the beginning and end of the study; days of intravenous antibiotics were noted. Nasopharyngeal aspirates were taken for viral studies during respiratory exacerbations. Serum was collected at enrollment and 2-6 weeks after each respiratory exacerbation. One hundred and fifty seven exacerbations occurred in 76 patients. Respiratory virus infection was detected in 44 exacerbations and rhinovirus was present in 16% (25/157) of exacerbations. Patients with one or more respiratory virus infections were compared with those who had none. When all respiratory virus infections were considered, patients had a significantly greater deterioration in Shwachman score and received significantly more days of intravenous antibiotics. When rhinovirus was considered separately, patients received significantly more days of intravenous antibiotics, but showed no deterioration in clinical status. However, patients infected with another respiratory virus had a significant decline in FEV1, with trends towards significance for decline in FVC and Shwachman score.
Newborn screening allows novel treatments for cystic fibrosis (CF) to be trialled in early childhood before irreversible lung injury occurs. As respiratory exacerbations are a potential trial outcome variable, we determined their rate, duration and clinical features in preschool children with CF; and whether they were associated with growth, lung structure and function at age 5 years.
Respiratory exacerbations were recorded prospectively in Australasian CF Bronchoalveolar Lavage trial subjects from enrolment after newborn screening to age 5 years, when all participants underwent clinical assessment, chest CT scans and spirometry.
168 children (88 boys) experienced 2080 exacerbations, at an average rate of 3.66 exacerbations per person-year; 80.1% were community managed and 19.9% required hospital admission. There was an average increase in exacerbation rate of 9% (95% CI 4% to 14%; p<0.001) per year of age. Exacerbation rate differed by site (p<0.001) and was 26% lower (95% CI 12% to 38%) in children receiving 12 months of prophylactic antibiotics. The rate of exacerbations in the first 2 years was associated with reduced forced expiratory volume in 1 s z scores. Ever having a hospital-managed exacerbation was associated with bronchiectasis (OR 2.67, 95% CI 1.13 to 6.31) in chest CT scans, and lower weight z scores at 5 years of age (coefficient −0.39, 95% CI −0.74 to −0.05).
Respiratory exacerbations in young children are markers for progressive CF lung disease and are potential trial outcome measures for novel treatments in this age group.
Cystic Fibrosis; Bronchiectasis; Respiratory Infection
Objective: To examine the impact of severe acute respiratory syndrome (SARS) on pulmonary function, exercise capacity, and health-related quality of life (HRQoL) among survivors.
Methods: 110 survivors with confirmed SARS were evaluated at the Prince of Wales Hospital, HK at the end of 3 and 6 months after symptom onset. The assessment included lung volumes (TLC, VC, RV, FRC), spirometry (FVC, FEV1), carbon monoxide transfer factor (TLCO adjusted for haemoglobin), inspiratory and expiratory respiratory muscle strength (Pimax and Pemax), 6 minute walk distance (6MWD), chest radiographs, and HRQoL by SF-36 questionnaire.
Results: There were 44 men and 66 women with a mean (SD) age of 35.6 (9.8) years and body mass index of 23.1 (4.8) kg/m2. Seventy (64%) were healthcare workers. At 6 months 33 subjects (30%) had abnormal chest radiographs; four (3.6%), eight (7.4%), and 17 (15.5%) patients had FVC, TLC, and TLCO below 80% of predicted values; and 15 (13.9%) and 24 (22.2%) had Pimax and Pemax values below 80 cm H2O, respectively. The 6MWD increased from a mean (SD) of 464 (83) m at 3 months to 502 (95) m (95% CI 22 to 54 m, p<0.001), but the results were lower than normal controls in the same age groups. There was impairment of HRQoL at 6 months. Patients who required ICU admission (n = 31) had significantly lower FVC, TLC, and TLCO than those who did not.
Conclusion: The exercise capacity and health status of SARS survivors was considerably lower than that of a normal population at 6 months. Significant impairment in surface area for gas exchange was noted in 15.5% of survivors. The functional disability appears out of proportion to the degree of lung function impairment and may be related to additional factors such as muscle deconditioning and steroid myopathy.
The present multicenter, randomized crossover study compared the safety and efficacy of continuous infusion with those of short infusions of ceftazidime in patients with cystic fibrosis. Patients with chronic Pseudomonas aeruginosa colonization received two successive courses of intravenous tobramycin and ceftazidime (200 mg/kg of body weight/day) for pulmonary exacerbation administered as thrice-daily short infusions or as a continuous infusion. The primary endpoint was the variation in the forced expiratory volume in 1 s (FEV1) during the course of antibiotic treatment. Sixty-nine of the 70 patients enrolled in the study received at least one course of antibiotic treatment. The improvement in FEV1 at the end of therapy was not statistically different between the two treatment procedures (+7.6% after continuous infusion and +5.5% after short infusions) but was better after continuous ceftazidime treatment in patients harboring resistant isolates (P < 0.05). The interval between the course of antibiotic treatments was longer after the continuous infusion than after the short infusion of ceftazidime (P = 0.04). The mean serum ceftazidime concentration during the continuous infusion was 56.2 ± 23.2 μg/ml; the mean peak and trough concentrations during the short infusions were 216.3 ± 71.5 and 12.1 ± 8.7 μg/ml, respectively. The susceptibility profiles of the P. aeruginosa isolates remained unchanged and were similar for both regimens. Quality-of-life scores were similar whatever the treatment procedure, but 82% of the patients preferred the continuous-infusion regimen. Adverse events were not significantly different between the two regimens. In conclusion, the continuous infusion of ceftazidime did not increase its toxicity and appeared to be as efficient as short infusions in patients with cystic fibrosis as a whole, but it gave better results in patients harboring resistant isolates of P. aeruginosa.
Published articles have described a lack of willingness to allow preventative measures, as well as other types of modern therapies, as an obstacle to providing medical care for Amish and Mennonite populations.
We present data regarding the 12 Amish and Mennonite patients at the SUNY Upstate Medical University Pediatric Cystic Fibrosis Center and three representative case reports.
Families of patients from these communities receiving care at our Center have accepted preventive therapy, acute medical interventions including home intravenous antibiotic administration, and some immunizations for their children with cystic fibrosis, which have improved the health of our patients. Some have even participated in clinical research trials. Health care education for both the child and family is warranted and extensive. Significant Cystic Fibrosis Center personnel time and fundraising are needed in order to address medical bills incurred by uninsured Amish and Mennonite patients.
Amish and Mennonite families seeking care for cystic fibrosis may choose to utilize modern medical therapies for their children, with resultant significant improvement in outcome.
Methods: A retrospective longitudinal study was performed to compare the clinical outcome over a period of 1 year of all patients attending the Manchester Adult CF Unit who received intravenous antibiotics at home or in hospital. The primary outcome measure was percentage change in forced expiratory volume in 1 second (FEV1) at the end of the 1 year period. Baseline "best" and "average" FEV1 values were established for each patient for the year before the study. The secondary outcome measures were percentage changes in forced vital capacity (FVC) and body weight.
Results: A total of 116 patients received 454 courses of intravenous antibiotics. At the end of 1 year there had been a mean percentage decline in FEV1 compared with the baseline "average" for patients treated mostly at home but an improvement in patients treated mostly in hospital (Tukey's HSD mean difference 10.1%, 95% CI 2.9 to 17.2, p = 0.003). For all patients there was a mean percentage decline in FEV1 from the baseline "best" value. For each course of treatment the mean percentage improvements in FEV1 at the end of the course from the start of the course were significantly higher for patients treated in hospital than for those treated at home.
Conclusions: Clinical outcome, as defined by spirometric parameters and body weight, was better after a course of treatment in hospital than after home treatment, and this benefit was maintained over 1 year of treatment. The results suggest that patients treated at home need closer supervision.
Intravenous (IV) antibiotic therapy for pulmonary exacerbations (PE) has been shown to improve pulmonary functioning for patients with cystic fibrosis (CF); however, little is known about its effects on pediatric health-related quality of life (HRQOL). This prospective study assessed the impact of IV treatment of a PE on generic and CF-specific HRQOL for children and adolescents with CF. Participants included 52 children and adolescents with CF experiencing a PE (Mage = 13.6 years; 54% males; MFEV1% predicted = 58.8%). HRQOL, pulmonary functioning, and body mass index were assessed before and after IV antibiotic treatment. Results of this prospective, observational study indicated significant improvements on CFQ-R Respiratory (Mchange score = 11.7; 95% CI = 6.3–17.1; p < .0001) and Weight (Mchange score = 15.9; 95% CI = 7.9–23.8; p < .0001) scales. The CF-specific measure was more sensitive to changes in HRQOL than the generic instrument. These data suggest that CF-specific HRQOL improves with treatment for a PE with IV antibiotics. The noted statistically and clinically significant changes in the CFQ-respiratory scale indicate that the measure may be beneficial to pulmonary health care teams.
Patient-reported outcomes; Intravenous antibiotics; Disease-specific; Minimal clinically important difference
purpose of this study was to provide some evidence of the validity of a
modified shuttle test (MST) by comparing performance on the MST with
peak oxygen consumption (V̇O2peak)
measured during a treadmill test in a group of adult patients with
with stable cystic fibrosis performed a ramped maximal treadmill test
(STEEP protocol) and the MST using a randomised balanced design.
relationship between the distance achieved on the MST and
V̇O2peak was strong
(r = 0.95, p<0.01) with 90% of the
variance in V̇O2peak explained by the
variance in MST distance. The relationship was represented by the
regression equation (with 95% confidence intervals)
V̇O2peak = 6.83 (2.85 to 10.80) + 0.028 (0.019 to 0.024)× MST distance.
provides evidence of the construct validity of the MST as an objective
measure of exercise capacity in adults with cystic fibrosis.
A randomized clinical crossover trial was carried out to compare the use in the home, during 1-week periods, of two commercially available chamber devices (the Aerochamber and the Spacer) and a standard metered-dose inhaler (MDI) in 24 patients with reversible bronchospasm and satisfactory inhaler technique. Measurements of peak flow, forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), ratio of FEV1 to FVC and forced midexpiratory flow rate were made immediately before and 15 minutes after inhalation of terbutaline sulfate. No difference was noted in results of spirometry, peak flow readings or side effects between the devices. The results of spirometry were better during the trial than immediately before it (p less than 0.01). The mean score for inhaler technique was significantly lower at follow-up than during the trial (p less than 0.001). The results suggest that in this population there is no advantage to using either a chamber device rather than an MDI or one chamber device rather than the other.
Background: Multiple breath inert gas washout (MBW) has been suggested as a tool for detecting early cystic fibrosis (CF) lung disease. A study was undertaken to compare the relative sensitivity of MBW and spirometry for detecting abnormal lung function in school age children with CF and to compare MBW results obtained from healthy children in the UK with those recently reported from Sweden.
Methods: Forced expiratory volume in 1 second (FEV1) and maximal expiratory flow when 25% of forced vital capacity remains to be expired (MEF25) were compared with the lung clearance index (LCI) derived from sulphur hexafluoride MBW in 22 children with CF aged 6–16 years and in 33 healthy controls.
Results: LCI was higher in children with CF than in healthy controls (mean difference 5.1 (95% CI of difference 4.1 to 6.1) and FEV1 and MEF25 z-scores were lower (mean difference –2.3 (95% CI –2.9 to –1.7) and –1.8 (95% CI –2.4 to –1.3), respectively; p<0.001 for all). There was a significant negative correlation between LCI and FEV1 (r2 = 0.62) and MEF25 (r2 = 0.46). However, while normal (⩾–1.96 z-scores) FEV1 and MEF25 results were seen in 11 (50%) and 12 (53%) children with CF, respectively, all but one of these children had an abnormally increased LCI. LCI was repeatable in both groups (within subject CV for three measurements 6% for CF and 5% for healthy children). In healthy subjects LCI was independent of age and virtually identical in the British and Swedish children (mean difference 0.1 (95% CI –0.1 to 0.4), p = 0.38)
Conclusions: MBW is reproducible between laboratories, generates normal ranges which are constant over childhood, and is more frequently abnormal than spirometry in children with CF.
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.
We performed spirometry and collected information on health and parents' lifestyle on a sample of 960 children aged 3–6.
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; IC95% 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.
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.
The risk of pulmonary exacerbation following Pseudomonas aeruginosa (Pa) acquisition in children with cystic fibrosis (CF) is unknown.
To determine if failure of antibiotic therapy to eradicate Pa and frequency of Pa recurrence are associated with increased exacerbation risk.
The cohort included 282 children with CF who participated in the EPIC trial ages 1–12 with newly acquired Pa, defined as either a first lifetime Pa positive respiratory culture or positive after two years of negative cultures (past isolation of Pa but >2 years prior to the trial). All received antibiotics to promote initial eradication followed by 15 months of intermittent maintenance antibiotics. Quarterly cultures were used to define initial eradication success and subsequent number of Pa recurrences. A standardized symptom-based definition of exacerbation was utilized. Cox proportional hazards models were used to estimate exacerbation risk.
Failure to initially eradicate Pa was associated with exacerbation risk (hazard ratio [HR]: 2.49, 95% confidence interval [CI] 1.26,4.93). In 245/282 with successful initial eradication during the trial, past isolation of Pa >2 years before the trial was the most significant predictor of exacerbation (HR 1.62, 95% CI 1.12,2.35). In 37/282 who failed initial eradication, persistent Pa during the maintenance phase (1 or more Pa recurrences after failure to initially eradicate) added even greater exacerbation risk (HR 4.13, 95% CI 1.28, 13.32).
Children with CF who fail to eradicate after initial antibiotic treatment are at higher risk of subsequent exacerbation, suggesting clinical benefit to successful early eradication of Pa infection.
New acquisition; early intervention; eradication; clinical outcome