Randomized trial comparing cryopreserved cultured epidermal allografts with hydrocolloid dressings in healing chronic venous ulcers. Evaluation of two calcium alginate dressings in the management of venous ulcers.
Cultured epidermal allografts have been successfully used to treat a variety of wounds. Their postulated mechanism of action is through release of cytokines that stimulate epithelialization. On the basis of previous experience we expected ulcers treated with cryopreserved cultured allografts (CCAs) to be healed by 6 weeks. Hydrocolloid dressings (HCDs) have also been reported to be effective in the treatment of venous ulcers.
                Our purpose was to compare the effectiveness of CCAs with HCDs in healing chronic venous ulcers.
                Forty-three patients with 47 ulcers were enrolled in a randomized controlled trial. Ulcers not healed by 6 weeks were changed to the other treatment.
                No difference in the number of healed ulcers between the two groups was observed at 6 weeks. Healing rate, percent reduction of initial ulcer size, and radial progression toward wound closure were significantly greater for CCAs than for HCDs. Pain relief was not significantly different.
                CCAs achieve more rapid healing and greater reduction in ulcer size than HCDs. Calcium alginate dressings facilitate the management of highly exudating wounds such as venous ulcers. To evaluate and compare the performance of two calcium alginate dressings in the management of venous ulcers, a prospective, randomized, controlled clinical study was conducted among 19 outpatients at two wound clinics in California. Ten patients (53%) were treated with Alginate A and nine patients (47%) with Alginate B. Dressings were changed weekly and patients were followed for a maximum of 6 weeks or until the venous ulcer no longer required the use of an alginate dressing. At each dressing change, the wound was assessed and dressing performance evaluated. Absorbency of exudate, patient comfort during wear, ease of removal, adherence to wound bed, dressing residue following initial irrigation, patient comfort during removal, ease of application, and conformability were assessed. Patients using Alginate A experienced significantly less foul odor (P = 0.02) and less denuded skin (P = 0.04) than Alginate B at follow-up wound assessments. With the exception of conformability, Alginate A was rated significantly better than Alginate B (P less than or equal to 0.05) in all dressing performance assessments. No significant healing differences were observed. As the different performance characteristics of various calcium alginate dressings become more obvious in clinical practice, further study is warranted to determine their optimal effectiveness.
The current evidence base does not suggest that alginate dressings are more or less effective in the healing of venous leg ulcers than hydrocolloid or plain non-adherent dressings, and there is no evidence to indicate a difference between different proprietary alginate dressings. However, the RCTs in this area are considered to be of low or unclear methodological quality. Further, good quality evidence is required from well designed and rigorously conducted RCTs that employ - and clearly report on - methods to minimise bias, prior to any definitive conclusions being made regarding the efficacy of alginate dressings in the management of venous leg ulcers.