Drug eluting biliary stents to decrease stent failure rates: A review of the literature

Table 3 Studies evaluating drug elution or coating to prevent internal failure

Ref.	Journal	Study design	Study results
In vitro
Rees et al[17]	Journal of Hospital Infection (1998)	In vitro	BZC and Teflon reduced the number of organisms attached to stents
		- control (polyurethane)
		- benzalkonium chloride (BZC)
		- ePTFE (Teflon)
Cetta et al[18]	The European Journal of Surgery (1999)	In vitro	Heparin and hyaluronic acid coating reduced biofilm development
		5 stents - control (polyurethane)
		5 stents - heparin + hyaluronic acid
Weickert et al[21]	Advances in Medical Sciences (2011)	In vitro	Stents coated with hydrophobin or both hydrophobin and heparin reduced clogging material scanning electron microscopy (SEM) images
		7 stents - control (polyethylene)
		4 stents - hydrophobin (H)
		3 stents - H + ampicillin/sulbactam
		3 stents - H + levofloxacin
		3 stents - H + heparin
Animals
Gwon et al[22]	Acta Radiologica (2012)	Canine model	Cefotaxime did not prevent biofilm development (gross inspection, SEM images)
		3 stents - control (ePTFE)
		3 stents - 10% wt/vol cefotaxime
		3 stents - 20% wt/vol cefotaxime
Humans
Farnbacher et al[19]	Scandinavian Journal of Gastroenterology (2012)	Randomized prospective	Heparin is effective in preventing encrustation on stents (encrustation weighed)
		13 stents - control (polyethylene)
		13 stents (same patients) - heparin