Lung maturation

from Wikipedia, the free encyclopedia

As lung maturation is the process of functional development of the lungs . It takes place before the birth and is a prerequisite for the onset of lung breathing immediately after the birth . Disturbances in lung maturation lead to asphyxiation after birth; lung maturation is problematic, especially in premature babies .

procedure

After the embryonic formation of the lung, it is initially a solid tissue that differentiates into a (pseudoglandular) tissue that is reminiscent of glandular tissue around the 8th week of pregnancy (SSW) . An initially undifferentiated, cubic epithelium forms . Around the 16th week of gestation, ducts (canalicular stage) form in the lung tissue and from around the 22nd week of pregnancy the epithelial cells differentiate into type 1 and type 2 pneumocytes . In the 27th week of pregnancy, the first sacs (saccular stage), which represent the preliminary stages of the alveoli , appear. From about the 28th week of pregnancy onwards, type 2 pneumocytes form surfactant , a surface-active substance that is of crucial importance for the development of the alveoli.

Lung maturation is controlled primarily by glucocorticoids . In addition, thyroid hormones , insulin and estrogens influence this process.

Medicinal influence on lung maturation

With the first fetal respiratory movements, surfactant also gets into the amniotic fluid , so that the status of lung maturation can be assessed by analyzing the amniotic fluid.

The administration of glucocorticoids and thyroid hormones promotes lung maturation and the formation of surfactant. In addition, it is now possible to administer surfactant obtained via lung lavage or synthetically produced to premature babies with respiratory distress syndrome .

Side effects

A new study links lung maturity with corticosteroids with later mental abnormalities and ADHD. This also fits in with the results that show that prenatal steroids alter children's brain development. Another study showed that repeated steroid doses every 14 days did not improve lung maturation but caused fetal growth disorders, so this treatment regimen is no longer recommended.

Individual evidence

  1. ↑ Natasha Khalife, Vivette Glover, Anja Taanila, Hanna Ebeling, Marjo-Riitta Järvelin, Alina Rodriguez, James G. Scott: Prenatal Glucocorticoid Treatment and Later Mental Health in Children and Adolescents. In: PLoS ONE. 8, 2013, p. E81394, doi: 10.1371 / journal.pone.0081394 .
  2. ^ Elysia Poggi Davis, Curt A. Sandman, Claudia Buss, Deborah A. Wing, Kevin Head: Fetal Glucocorticoid Exposure Is Associated with Preadolescent Brain Development. In: Biological Psychiatry. 74, 2013, pp. 647-655, doi: 10.1016 / j.biopsych.2013.03.009 .
  3. ↑ Kellie E Murphy, Mary E Hannah, Andrew R Willan, Sheila A Hewson, Arne Ohlsson, Edmond N Kelly, Stephen G Matthews, Saroj Saigal, Elizabeth Asztalos, Susan Ross, Marie-France Delisle, Kofi Amankwah, Patricia Guselle, Amiram Gafni , Shoo K Lee, B Anthony Armson: Multiple courses of antenatal corticosteroids for preterm birth (MACS): a randomized controlled trial. In: The Lancet. 372, 2008, pp. 2143-2151, doi : 10.1016 / S0140-6736 (08) 61929-7 .

literature

  • JW Dudenhausen: gynecology and obstetrics. 2nd Edition. Walter de Gruyter, 2002, ISBN 3-11-016562-7 , pp. 115-116.
  • Hermann M Behre, Christoph Keck: Endocrinology, reproductive medicine, andrology. 2nd Edition. Georg Thieme Verlag, 2002, ISBN 3-13-107162-1 , p. 43.