Topical Treatment of Pressure Ulcers

In a single-blind, randomized trial, the efficacy of topical streptokinase-streptodornase (Varidase@) solution was compared with that of zinc oxide on necrotic pressure ulcers in 28 patients. The effectiveness was determined by measuring the necrosis removal within 8 weeks. This occurred in 6 patients (43%) treated with Varidase@ and in 7 (50%) treated with zinc oxide. The statistical tests applied showed no significant difference between the two treatments despite the use of a high power (I-j3=0.95). The data suggest that the two regimens are about equally effective in the treatment of necrotic tissue. Pressure ulcers are found mostly in elderly patients (Barbenel, Jordan, Nicol & Clark, 1977; Ek & Boman, 1982). Generally non-surgical measures are indicated in the management of these ulcers (Daniel, Hall & MacLeod, 1979; Morgan, 1975). The aim is to cleanse the ulcer of necrotic and dead tissue, prevent infection and promote healing (Reuler & Cooney, 1981). Many topical agents have been claimed to fulfil one or more of these requirements (Jacobsson, Rothman, Arturson, Ganrot, Haeger & Juhlin, 1976; Moberg, Hoffman, Grennert & Holst, 1983; Morgan). However, few have been adequately assessed under clinical conditions (Morgan). Streptokinase-streptodornase (Varidase@) for topical application is an enzymatic preparation widely used in wound management (Hellgren, 1983). Steptokinase works indirectly by transforming plasminogen into the active proteolytic enzyme plasmin via streptokinase-proactivator complex. Streptodornase dissolves deoxyribonucleoproteins commonly present in pus (Hellgren). Varidase@ is believed to be beneficial in the treatment of necrotic (Hellgren; Suornalainen, 1983) and infected wounds (Poulsen, Kristensen, Brygger & Delikaris, 1983). Zinc administered systemically increases the rate of healing in zinc deficient patients (Hallbook & Lanner, 1972), although its mode of action is not fully understood. A double-blind, placebo-controlled trial showed that topical zinc oxide improved the healing of ulcers (Stromberg & Agren, in press). The compound appeared to have a cleansing effect as well. In an attempt to compare objectively Varidase@ and zinc oxide in the local treatment of necrotic pressure ulcers, this randomized, open trial was carried out. PATIENTS AND METHODS Twenty-eight geriatric patients with one or more necrotic pressure ulcers were admitted to the trial. The ulcers studied ranged between I and 50 cmz in surface area and extended maximally to the subcutaneous fat. There were 20 women and 8 men in the study group, whose median age was 84 years (range 46-92 years). Twenty-four were hospitalized patients and 4 were out-patients. Nine patients had diabetes mellitus. Patients were consecutively matched in pairs. Each member of the pair was randomly allocated to either topical treatment with Varidase or treatment with zinc oxide. The two groups were comparable with respect to age, sex and other characteristics shown in Table I. Patients assigned to zinc treatment were given dry, sterile gauze compresses premedicated with zinc oxide (400 pg ZnOlcm’). The Varidase solution (1OOOOO IU streptokinase and 25000 IU streptodornase dissolved in 20 ml sterile isotonic saline solution; Lederle Laboratories) was applied on a sterile gauze compress. Zinc dressings were changed once a day and Varidase twice daily according to the manufacturer’s recommendations. Dressings were secured with porous acrylic-based tapes. In the case of multiple necrotic ulcers, these were treated uniformly, but only the largest was monitored. Before the study began, loosely attached necrotic material was removed, but ulcers were not surgically debrided subsequently. No pa7-858221 Scand J Plast Reconstr Surg 19 Sc an d J Pl as t S ur g R ec on tr S ur g H an d Su rg D ow nl oa de d fr om in fo rm ah ea lth ca re .c om b y K U L eu ve n on 0 9/ 28 /1 2 Fo r pe rs on al u se o nl y.