42 research outputs found
Zien of raden?
Rede,
uitgesproken bij de aanvaarding
van het ambt van bijzonder hoogleraar
kinderpulmonologie, in het bijzonder
de ontwikkeling van de long,
aan het Erasmus MC, Faculteit van de
Erasmus Universiteit Rotterdam
op 12 februari 201
Annual lung function changes in young patients with chronic lung disease
Reference equations for ventilatory function that use different
statistical models may introduce artifacts that affect the estimated
change of lung function during growth in young subjects. The effect of
differently modelled reference equations on the estimated annual change of
forced expiratory volume in one second (FEV1) and forced vital capacity
(FVC) in young patients with chronic lung disease was assessed. Four
frequently used reference equations were used to describe the longitudinal
changes of FEV1 and FVC in 52 patients (23 females) with cystic fibrosis
(CF) during a mean follow-up of 3.9 yrs. Choice of reference equations
directly affected value and, most importantly, estimated annual change of
FVC and FEV1. Mean+/-SD annual change of FEV1 varied from 2.2+/-6.2 to
-2.2+/-3.6% of predicted. For two reference equations the estimated
individual changes of FEV1 and FVC in CF were positively correlated wit
Extra-fine particles improve lung delivery of inhaled steroids in infants: a study in an upper airway model
BACKGROUND: The particles of a new hydrofluoroalkane-134a
(HFA)-beclomethasone dipropionate (BDP) metered-dose inhaler (Qvar; 3M
Pharmaceuticals; St. Paul, MN) are considerably smaller than those of
chlorofluorocarbon (CFC)-BDP. This may improve lung deposition in infants
who inhale nasally and have irregular breathing patterns and small
airways. Aim: To compare the dose delivered to the lungs of HFA-BDP and
CFC-BDP at different breathing patterns using an upper airway model of an
infant. METHODS: An anatomically correct upper airway model of a
9-month-old child with an open nasal airway was connected to an impactor
and breathing simulator. HFA-BDP, 100 microg, and CFC-BDP, 100 micro g,
were delivered to the model through a detergent-coated, small-volume
spacer. The total dose leaving the model (lung dose), its particle size
distribution, and median mass aerodynamic diameter (MMAD) were assessed
during simulated tidal breathing with tidal volumes (VTs) of 50 mL, 100
mL, and 200 mL, and 30 breaths/min. Dose was expressed as percentage of
nominal dose. RESULTS: Lung doses for HFA-BDP were 25.4%, 26.5%, and 30.7%
compared with 6.8%, 4.8%, and 2.1% for CFC-BDP at VTs of 50 mL, 100 mL,
and 200 mL, respectively. The dose of particles < 2.1 microm to the lung
for HFA-BDP was 23 to 28% compared with 0.6 to 0.8% for CFC-BDP. The lung
dose of CFC-BDP mainly consisted of particles between 2.1 microm and 4.7
microm. MMAD for HFA-BDP was 1.2 microm, and 2.6 to 3.3 microm for CFC-BDP
depending on VT. The lung dose for CFC-BDP decreased significantly with
increasing VT. HFA-BDP lung dose did not alter significantly with VT.
CONCLUSIONS: In this infant model study, the use of HFA-BDP with a high
dose of particles < 2.1 microm improves the dose delivered to the lungs
substantially. Furthermore, the large proportion of extra-fine particles
in HFA-BDP results in lung doses less dependent on breathing pattern
compared with CFC-BDP
Variability of aerosol delivery via spacer devices in young asthmatic children in daily life
Pressurized metered dose inhalers (pMDI) are widely used together with
spacers for the treatment of asthma in children. However, the variability
of daily medication dose for pMDI/spacer combinations is not known.
Electrostatic charge is a potential source of dose variability. Metal
spacers have no static charge. This study assessed and compared
within-subject variability of aerosol delivery of metal and plastic
spacers. This was a randomized, crossover study in children with stable
asthma aged 1-4 (group I, n=17) and 5-8 (group II, n=16) yrs. In both
groups the amount of drug delivered to the mouth by a metal spacer
(Nebuchamber) and one of two plastic (polycarbonate) spacers, i.e.
Babyhaler in group I and Volumatic in group II was measured. The metal and
plastic spacers were tested at home in a randomized order for 7 days each,
using budesonide (200 microg b.i.d.). Aerosol was collected on a filter
positioned between spacer and facemask or mouth. Budesonide on the filter
was assessed by high performance liquid chromatography. The mean filter
dose for each child (mean+/-SD) during the 7 days was expressed as a
percentage of the nominal dose. Within-subject variability was expressed
as coefficient of variation (CV). Mean filter dose in group I was
41.7+/-10.1% for Nebuchamber and 26.0+/-4.0% for Babyhaler (p<0.001). Mean
filter dose in group II was 50.2+/-9.2% for Nebuchamber and 19.4+/-7.2%
for Volumatic (p<0.001). Mean CV in group I was 34% for Nebuchamber and
37% for Babyhaler (p=0.44). Mean CV in group II was 23% for Nebuchamber
and 34% for Volumatic (p=0.003). There was substantial within-subject dose
variability in aerosol delivery in children using a pMDI/spacer at home.
This variability was lower for the metal than for the plastic spacer in
children 5-8 yrs of age. The dose delivered to the mouth was about
two-fold higher fo
The development of bronchiectasis on chest computed tomography in children with cystic fibrosis: can pre-stages be identified?
Objective: Bronchiectasis is an important component of cystic fibrosis (CF) lung disease but little is known about its development. We aimed to study the development of bronchiectasis and identify determinants for rapid progression of bronchiectasis on chest CT. Methods: Forty-three patients with CF with at least four consecutive biennial volumetric CTs were included. Areas with bronchiectasis on the most recent CT were marked as regions of interest (ROIs). These ROIs were generated on all preceding CTs using deformable image registration. Observers indicated whether: bronchiectasis, mucus plugging, airway wall thickening, atelectasis/consolidation or normal airways were present in the ROIs. Results: We identified 362 ROIs on the most recent CT. In 187 (51.7 %) ROIs bronchiectasis was present on all preceding CTs, while 175 ROIs showed development of bronchiectasis. In 139/175 (79.4 %) no pre-stages of bronchiectasis were identified. In 36/175 (20.6 %) bronchiectatic airways the following pre-stages were identified: mucus plugging (17.7 %), airway wall thickening (1.7 %) or atelectasis/consolidation (1.1 %). Pancreatic insufficiency was more prevalent in the rapid progressors compared to the slow progressors (p = 0.05). Conclusion: Most bronchiectatic airways developed within 2 years without visible pre-stages, underlining the treacherous nature of CF lung disease. Mucus plugging was the most frequent pre-stage. Key Points: • Development of bronchiectasis in cystic fibrosis lung disease on CT.• Most bronchiectatic airways developed within 2 years without pre-stages.• The most frequently identified pre-stage was mucus plugging.• This study underlines the treacherous nature of CF lung disease
Physiological and morphological determinants of maximal expiratory flow in chronic obstructive lung disease
Maximal expiratory flow in chronic obstructive pulmonary disease (COPD)
could be reduced by three different mechanisms; loss of lung elastic
recoil, decreased airway conductance upstream of flow-limiting segments;
and increased collapsibility of airways. We hypothesized that decreased
upstream conductance would be related to inflammation and thickening of
the airway walls, increased collapsibility would be related to decreased
airway cartilage volume, and decreased collapsibility to inflammation and
thickening of the airway walls. Lung tissue was obtained from 72 patients
with different degrees of COPD, who were operated upon for a solitary
peripheral lung lesion. Maximal flow-static recoil (MFSR) plots to
estimate upstream resistance and airway collapsibility were derived in 59
patients from preoperatively measured maximal expiratory flow-volume and
pressure-volume curves. In 341 transversely cut airway sections, airway
size, airway wall dimensions and inflammatory changes were measured.
Airflow obstruction correlated with lung elastic recoil and the MFSR
estimate of airway conductance but not to airway collapsibility or to the
amount of airway cartilage. The upstream conductance decreased as the
inner wall became thicker. Airway collapsibility did not correlate with
the amount of airway cartilage, inflammation, or airway wall thickness. We
conclude that the maximal flow-static recoil model does not adequately
reflect the collapsibility of the flow-limiting segment
Structure and function of small airways in asthma patients revisited
Small airways (<2 mm in diameter) are probably involved across almost all asthma severities and they show proportionally more structural and functional abnormalities with increasing asthma severity. The structural and functional alterations of the epithelium, extracellular matrix and airway smooth muscle in small airways of people with asthma have been described over many years using in vitro studies, animal models or imaging and modelling methods. The purpose of this review was to provide an overview of these observations and to outline several potential pathophysiological mechanisms regarding the role of small airways in asthma
Progressive damage on high resolution computed tomography despite stable lung function in cystic fibrosis
For effective clinical management of cystic fibrosis (CF) lung disease it
is important to closely monitor the start and progression of lung damage.
The aim of this study was to investigate the ability of high-resolution
computed tomography (HRCT) scoring systems and pulmonary function tests
(PFT) to detect changes in lung disease. CF children (n=48) had two H
The radiological diagnosis of bronchiectasis: What’s in a name?
Diagnosis of bronchiectasis is usually made using chest computed tomography (CT) scan, the current gold standard method. A bronchiectatic airway can show abnormal widening and thickening of its airway wall. In addition, it can show an irregular wall and lack of tapering, and/or can be visible in the periphery of the lung. Its diagnosis is still largely expert based. More recently, it has become clear that airway dimensions on CT and therefore the diagnosis of bronchiectasis are highly dependent on lung volume. Hence, control of lung volume is required during CT acquisition to standardise the evaluation of airways. Automated image analysis systems are in development for the objective analysis of airway dimensions and for the diagnosis of bronchiectasis. To use these systems, clear and objective definitions for the diagnosis of bronchiectasis are needed. Furthermore, the use of these systems requires standardisation of CT protocols and of lung volume during chest CT acquisition. In addition, sex-and age-specific reference values are needed for image analysis outcome parameters. This review focusses on today’s issues relating to the radiological diagnosis of bronchiectasis using state-of-the-art CT imaging techniques