Background and objective:
The mechanism by which iodopovidone achieves pleurodesis is unknown.
This study investigated whether iodopovidone is as effective as
doxycycline in producing pleurodesis and whether systemic
corticosteroids diminish its efficacy.
Methods:
Four groups of seven New Zealand rabbits were assigned to the following
intrapleural treatment groups: 2 mL of 2% iodopovidone, 2 mL of 4%
iodopovidone, 2 mL of 4% iodopovidone plus 0.8 mg/kg triamcinolone
intramuscularly weekly and 10 mL/kg doxycycline in 2 mL. Pleural fluid
was collected 24, 48 and 72 h after intrapleural injections and analysed
for WCC, protein and LDH levels. The rabbits were killed 2 weeks after
the injections. Pleurodesis was graded macroscopically on a scale from 1
to 8. The degree of microscopic pleural fibrosis and pleural
inflammation was graded from the HE stain slides.
Results:
The mean volume of pleural fluid as well as the mean total WCC was
significantly lower in the steroid-treated group than in the other
groups. The degree of the resulting pleurodesis was similar in the 2%
iodopovidone (7.00 +/- 1.29), 4% iodopovidone (7.71 +/- 0.76) and
doxycycline (7.14 +/- 0.90) groups (P > 0.05) whereas the pleurodesis
score of the steroid group (3.71 +/- 1.98) was significantly lower than
all other groups (P < 0.05). The degree of microscopic pleural fibrosis
and pleural inflammation was significantly lower in the steroid group
than in the 2% iodopovidone or 4% iodopovidone group.
Conclusions:
Both 2% and 4% iodopovidone can induce pleurodesis as efficaciously as
doxycycline in rabbits. Systemic corticosteroids significantly decrease
the efficacy of iodopovidone in producing pleurodesis