Infectious

Commercially available fibrin sealant carries a theoretical risk of viral contamination because it is manufactured from pooled human-plasma components.

■ Advances in viral inactivation technology have significantly reduced the risk of hepatitis A, B, and C, and HIV transmission.

Various viral inactivation techniques including vapor heating, steam treatment, pasteurization, irradiation, solvent detergent extraction, and nanofiltration have been utilized (6).

Careful donor selection strategies and screening plasma units intended for sealant production are another factors reducing the risk of viral transmission.

To avoid viral transmission, Tisseel is prepared from plasma donated from screened donors, and tested for viral contaminants. Furthermore, Tisseel manufacturing includes a two-step vapor-heated method for viral inactivation (Table 2) (54). In addition to donor screening and plasma testing human immuno defficiency virus, hepatitis A, B, and C, and parvovirus B19, both solvent detergent and pasteurization for viral inactivation can be used to produce Crosseal (Table 2) (21). Although Costasis prevents viral transmission altogether by collecting a patient's own blood as a source of autologous fibrinogen, it relies on bovine thrombin. Four cases of parvovirus B19 transmission have occurred in Japan (55,56). None of these preparations was approved by Food and Drug Administration and there are no reports of such a transmission in Europe or the United States so far.

Although no case of viral transmission using bovine thrombin has been reported, bovine spongiform encephalopathy is a theoretical risk (6). The risk of prion transmission is thought to be very low but cannot be entirely eliminated.

TABLE2 ■ Characteristics of Available Fibrin Sealants and a Fibrin-Sealant Variant

Fibrin

Human

Bovine

Intact coagulation

Preparation

sealant

Manufacturer

Viral inactivation method

derived

derived

pathway required

time (min)

Tisseel

Baxter Healthcare

Two-step vapor heating

Yes

Yes

No

20

Corporation

Crosseal

American Red Cross, Inc.

Solvent/detergent, pasteurization

Yes

No

No

1

Hemaseal

Haemacure Corp.

two-step vapor heating

Yes

Yes

No

20

VIGuard

Vitex: VI Technologies

Solvent/detergent, ultraviolet C light

Yes

Yes

No

Biocol

LFB-Lille

Solvent/detergent

Yes

Yes

No

Quixil

Omrix Biopharmaceuticals

Solvent/detergent,

Yes

Yes

No

pasteurization/nanofiltration

Beriplast

Aventis Behring

Pasteurization

Yes

Yes

No

Bolheal

Kaketsuken Pharmaceutical

Dry heat

Yes

Yes

No

Costasis

Angiotech Pharmaceuticals Inc.

Not available

Autologous

Yes

No

>20

The use of hemostatic agents implies potential risks of allergic reactions because bovine thrombin is immunogenic. Sudden and severe hypotension resulting in death has been reported after applying bovine thrombin to a deep hepatic wound, and immune-mediated coagulopathy from bovine thrombin is a well-recognized complication.

Careful donor selection strategies and screening plasma units intended for sealant production are another factors reducing the risk of viral transmission.

Although no case of viral transmission using bovine thrombin has been reported, bovine spongiform encephalopathy is a theoretical risk. The risk of prion transmission is thought to be very low but cannot be entirely eliminated.

Cyanoacrylates are synthetic monomers that have generally been applied externally for the closure of lacerations, wounds, and incisions. Although stronger than fibrin sealants, they are not bioabsorbable and, if not used topically, behave as any other foreign body causing inflammation, tissue necrosis, or infection.

Until prospective clinical trials are performed, the efficacy of Coseal and Focalseal-L in urologic laparoscopy remains uncertain. Nevertheless, synthetic sealants are advantageous because allergic and viral transmission risks are nonexistent and because intact clotting pathways are unnecessary.

Nanofiltration appears to be the best technique to improve the safety of fibrin-sealant components because the Creutzfeld-Jakob agent can be filtered from infected brain extracts of mice using a 35 nm pore size filter membrane (57).

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