PURPOSE:Treatment of pleural effusions often consists of attempts at creating a pleural symphysis with a sclerosing agent, usually administered as a single bolus dose. We have previously demonstrated that low dose repeated administration of silver nitrate (SN) as compared to single high dose administration can lead to effective pleurodesis, but such dosing regimen would be impractical in patients.
METHODS:A catheter coating capable of eluting SN over 14 days was designed and tested in a well described in-vivo animal pleurodesis model. Three groups of six animals (SPF New Zealand white rabbits) underwent placement of uncoated, 24mg SN and 50mg SN catheters in the right pleural space. Catheters were removed on day 15 and necropsy performed on day 29. Efficacy of pleurodesis was assessed by a 1–8 score (1-normal, 8-pleural symphysis >50% hemithorax), with a score of ≥5 considered significant.
RESULTS:Mean pleurodesis scores on the treated (right) side were 1.0, 4.8 and 6.3 for the uncoated, 24mg and 50mg groups respectively (p= 0.001 vs. uncoated for each SN group). Scores for the untreated (left) side were 1.0, 1.0 and 1.6 for the uncoated, 24mg and 50mg groups respectively.
CONCLUSION:A SN eluting coated catheter appears to be effective in creating pleurodesis.
CLINICAL IMPLICATIONS:This approach could potentially be useful in achieving pleurodesis on an outpatient basis for patients with a variety of pleural diseases. The use of lower peak doses of sclerosing agents may also reduce the frequency and severity of side-effects.
DISCLOSURE:Alain Tremblay, None.