Luftrørbuds

Luftrørbuds is a term used in some Scandinavian medical literature to refer to the embryonic airway buds that form the lower respiratory tract, including the trachea and the bronchial tree, from the ventral foregut during early development.

In embryology, the luftrørbuds arise as outgrowths from the laryngotracheal diverticulum, which itself develops from the ventral foregut in the early weeks of gestation. The first recognizable structures are the right and left primary bronchial buds, which subsequently branch repeatedly to establish the bronchial tree. The luftrørbuds are lined by endoderm and are enveloped by mesenchyme that differentiates into cartilage, smooth muscle, and connective tissue, supporting the growing airways.

Functionally, these buds serve as the precursors to the mature conducting airways, providing a conduit for air to reach the lungs. The branching morphogenesis that begins with the luftrørbuds establishes the extensive network of bronchi, bronchioles, and ultimately the alveolar structures involved in gas exchange.

Clinical relevance centers on airway development. Abnormal formation or branching of the luftrørbuds can contribute to congenital anomalies such as tracheoesophageal fistulas, tracheal stenosis, or hypoplastic lungs. Prenatal imaging and postnatal assessment may be required to evaluate suspected airway malformations and guide management.

See also: respiratory tract development; laryngotracheal diverticulum; bronchial buds; congenital malformations of the respiratory system.