Objectives: Partial liquid ventilation with perfluorooctyl bromide (perflub
ron) has been shown to be safe and effective in animal models with respirat
ory failure. However, airway mucus accumulation has been reported to be a p
roblem in human trials. We hypothesized that this might be because perflubr
on directly affects mucociliary clearance or stimulates mucus secretion.
Methods and results: We first measured the mucociliary transportability of
secretions on the mucus-depleted frog palate exposed to perflubron and demo
nstrated that the ciliated epithelium remained intact with preservation of
mucociliary transport. We then measured mucin and lysozyme secretion from i
solated ferret tracheal segments to evaluate the secretagogue potential of
perflubron. There was an 86% increase in mucin secretion with perflubron in
cubation at 40 min (n = 19; p < 0.01) and a 52% increase after 4 h of expos
ure followed by evaporation of perflubron (n = 19; p < 0.01). There was no
significant difference in lysozyme secretion at any time between perflubron
-exposed or buffer-exposed tissue (n = 4). The secretagogue effect was comp
letely blocked by nordihydroguaiaretic acid, an inhibitor of arachidonic ac
id (AA) metabolism.
Conclusion: These data suggest that although perflubron does not seem to be
harmful to the airway, it induces mucus secretion in a noninflamed airway,
and that this can be modulated by inhibitors of AA metabolism.