Jwc ewma final indd

J O U R N A L  O F WO U N D  C A R E   Vo l   2 2 .  N o   1 .  E W M A   D o c u M E N t   2 0 1 3  

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streptokinase. A combination of streptokinase and 

streptodornase is commercially available.

Papain digests necrotic tissue by liquefying 

fibrinous debris across a wide range of pH, from 3 

to 12.

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 For its full activity, it requires the presence 

of sulphydryl groups, such as cysteine. Usually, 

urea is combined with papain. Urea also denatures 

proteins, making them more susceptible to 

proteolysis by papain and exposes the necessary 

activators for papain in necrotic tissue.

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 It should 

be noted that papain is not commercially available 

in all parts of the world.

Krill enzymes (euphauserase) are a complex mixture 

of endo- and exopeptidases, which are isolated from 

the gastrointestinal tract of Antarctic krill (Euphausia 

superba). The acidic endopeptidases have a structural 

relationship to trypsin and chymotrypsin, whereas 

the exopeptidases are mainly carboxypeptidases A 

and B. A high molecular similarity to crab 

collagenase could be found for the serin 

endopetidase euphauserase. Krill enzymes assure a 

nearly-complete breakdown of proteinous substrates 

to soluble free amino acids.

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Administration

To ensure the full effectiveness during the therapy 

with proteolytic enzymes, the wounds must always 

have sufficient moisture in the environment. 

Application of the enzymatic ointment should be 

performed in a coating of thickness about 2–3mm 

on the non-viable tissue areas, once or twice daily.

Benefits

The main advantages of the use of proteolytic 

enzymes in the debridement of patients with 

chronic wounds are their easy and safe handling. 

Therapies are bloodless and generally considered 

rather painless.

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 Because of the highly-selective 

mode of action, this type of debridement can be 

appropriate to use in long-term care facilities and 

in home-care settings. 

Contraindications

It is important to respect the fact that 

enzymes need a moist environment to be 

effective. Therefore, dry wounds are a relative 

contraindication for the use of proteolytic enzymes. 

The additional use of, for example, antiseptics or 

soaps should be avoided, as some of the enzymes 

become ineffective in the presence of these 

solutions. A contraindication for streptokinase is 

the acute wound, because the cleavage of fibrin 

leads to an increased risk of bleeding.

Sideeffects

Products with proteolytic enzymes can lead to 

irritation of the peri-wound skin, with clinical signs 

of inflammation or discomfort. This, in particular, is 

most important when using papain, as considerable 

pain induced by inflammatory response has 

been commonly described.

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 In an attempt to 

reduce the occurrence of pain induced by papain, 

chlorophyllin has been added to these preparations.

Therapy with streptodornase can cause fever, 

chills, and leucocytosis, due to the absorption of 

split purines and pyrimidines. Streptokinase and 

streptodornase are effective as antigens and thus 

the formation of antibodies may result. In some 

cases, clinically-relevant contact sensitisation, with 

allergic contact dermatitis, has been reported.

Costeffectiveness

Proteolytic debridement is an easy-to-handle and 

safe option for conservative debridement; however, 

additional costs may occur due to the prolonged 

period of time needed to achieve complete 

removal of necrotic tissue, and due to the relatively 

expensive ointments. 

Absorptive dressings

Background

Dextranomer is a hydrophilic, dextran polymer, 

which is supplied as anhydrous, porous, spherical 

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