Ultrastructure and mucociliary transport of bronchial respiratory epithelium in intubated patients

Abstract

The objective of this study was to investigate whether reduced bronchial mucus transport velocity (BTV) is associated with a loss of cilia or ultrastructural abnormalities of cilia in intubated patients. The patients were studied prospectively in a convenience sample trial. The study took place in a university hospital. 29 orally intubated patients in a surgical ICU. BTV was measured with radiolabeled microspheres in the right and left primary bronchus. Following these measurements, biopsy samples were taken from the bronchi for scanning (SEM) and transmission (TEM) electron-microscopic investigations. SEM: Patients with normal or slight impaired BTV (group 1,n=14: BTV: 8.5 mm/min (3.8–11.5); median with range) showed more cilia on the luminal surface than patients with markedly depressed BTV (pn=15: BTV: 0(0–2.1)). The difference was statistically significant. The BTV values correlated moderately with the number of cilia on the luminal surface (r=0.46;p=0.02). TEM: In group 1, 6.5% (3.9–14.9) of cilia were abnormal (median with range) vs 9.3% (4.9–13.7) in group 2; these differences were not statistically significant. Neither was there any significant correlation between BTV and the frequency of abnormal cilia. Impaired mucociliary transport in intubated patients is associated with a loss of cilia rather than ultrastructural abnormalities of cilia, which are less relevant.