Long-term lung function, exercise endurance, participation and quality of life in congenital diaphragmatic hernia

In the Netherlands 50-60 newborns with congenital diaphragmatic hernia (CDH)
are being born each year. The mortality and morbidity mainly depend on the
extent of lung hypoplasia and structural abnormalities of the pulmonary
arteries, resulting in persistent pulmonary hypertension of the newborn.
Artifiicial ventilation with high pressures and high oxygen concentrations are
needed. Long-term pulmonary sequelae include peripheral airway obstruction and
increased bronchial responsiveness. Both lung injury due to artificial
ventilation and residual lung hypoplasia seem important determinants of
persistent lung function abnormalities in CDH patients. Few data are available
with respect to exercise endurance in CDH patients. Long-term follow-up in
adult CDH patients is limited and restricted to small, cross-sectional studies
which include lung function tests but not exercise endurance. More information
on lung function abnormalities, exercise endurance, and perception of exercise
endurance in young adults with CDH may be beneficial to develop intervention
studies at an early stage to prevent complication at the long term, e.g.
hypertension, obesity and diabetes.

The aim of the present study is to evaluate the long-term pulmonary sequelae,
exercise endurance and perception of exercise endurance in adult CDH patients
in a cohort that has been studied earlier at a median age of 11.7 years. Lung
function results will be compared with earlier data.
Furthermore, the extent of fatigue, quality of life and participation will be
evaluated. Data will be compared with data of controls matched for age,
gestational age, birth weight, duration of artificial ventilation, duration of
supplemental oxygen therapy and sex.

One part has a longitudinal design (lung function), one part has a
cross-sectional design (exercise endurance)

The extent of the burden includes a one-day hospital visit. Blood withdrawal
will be performed by an experienced physician shortly before and directly after
the exercise test. One or two ml of blood will be taken twice; this small
amount is not supposed to cause any problems for participants. Venous puncture
for blood withdrawal might lead to extravascular bleeding and occurance of a
hematoma which may cause a little burden for participants for a short period of
time.
In 30 patients who join a pilot study evaluating the daily physical activity
during 48 hours the burden includes: carrying a small monitor around the waist
for 48 hours without being able to shower or swim.
Subjects undergoing lung function tests will be asked to stop inhalation of
short-acting and long-acting bronchodilators shortly before the tests,
according to international standardized guidelines for lung function
measurements. A physician will discuss this by phone beforehand, to evaluate
whether this can be done without any problems.
Using a standardized questionnaire (PAR-Q) patients will be screened for
contraindications to perform maximal exercise tests. In addition a medical
history and physical examination will be performed to evaluate safety of
maximal exercise performance. In any case of suspicion, subjects will be
excluded from this part of the study. During maximal exercise performance a
physiotherapist experienced in Basic Life Support is present continuously. All
other tests are without risks.