Objective: To evaluate the role of surfactant in the mechanism and tre
atment of acute lung injury caused by inhalation of fabric protector.
Design: Prospective, randomized study. Setting: University laboratory.
Interventions: In vitro experiment: a porcine surfactant suspension (
10 mg . ml(-1)) was exposed to a fabric protector aerosolized with an
ultrasonic nebulizer for 1 min. Minimum surface tension (gamma min) wa
s sequentially measured using pulsating bubble equipment. Animal exper
iment: 14 adult rats were anesthetized with pentobarbital and mechanic
ally ventilated with pure oxygen. Then, all rats inhaled fabric protec
tor aerosolized with the nebulizer for five breaths. Three hours after
inhalation, the rats were randomly assigned to two groups: a surfacta
nt group (n = 7), in which surfactant (100 mg . kg(-1)) was replaced,
and a control group (n = 7), in which no substance was given. Measurem
ents and results: In vitro experiment: exposure to fabric protector ae
rosol increased the mean gamma min of the surfactant from 1.7 to 19.2
mN . m(-1) (n = 5, p < 0.05). Animal experiment: the mean partial pres
sure of oxygen in arterial blood (PaO2) in all rats decreased from 62.
8 to 17.1 kPa at 3 h after inhalation. The PaO2 in the surfactant grou
p increased to 49.8 +/- 11.1 (SD) kPa at 30 min after surfactant repla
cement (p < 0.05), while the PaO2 in the control group remained below
20 kPa. Conclusions: Impairment of surfactant is a factor involved in
the development of acute lung injury caused by inhalation of fabric pr
otector. Surfactant replacement may be therapeutic for such injuries.