ABSTRACT
The effect of electrostimulation on healing of a 6 cm long incision on the dorsum of rats was investigated. Postoperative stimulation was given with direct current (DC) to ten rats, and with alternating current (AC) to ten. Non-stimulated controls were used for each group. The words were biomechanically and biochemically tested three days after the final stimulation. Both DC and AC stimulation caused significant increase of the collagen content around the incision line compared with controls, but the collagen increase did not affect the tensile strength or the energy absorption. Electrostimulation of short duration is concluded to have a minor but significant enhancing effect on the formation of collagen in clean surgical wounds, but no effect on mechanical wound strength in the early postoperative period.
Subject(s)
Electric Stimulation Therapy/methods , Wound Healing/physiology , Animals , Biomechanical Phenomena , Collagen/analysis , Male , Rats , Rats, Inbred Strains , Skin/chemistry , Skin/physiopathologyABSTRACT
The effect of an enzymatic preparation for wound cleaning (Varidase) on the mechanical properties of absorbable sutures (Dexon) was studied in vitro and in vivo in a rat model. In vitro the sutures demonstrated a significant decrease in strength (breaking strength and energy absorption) and extensibility after 12 days of incubation in saline. Incubation in Varidase, however, further decreased the mechanical properties significantly. The stiffness of the sutures was independent of treatment and time. In vivo changes of mechanical properties of the sutures resemble those of the in vitro study, except for a decrease in stiffness of the sutures. The sutures in a primary closed wound had the same strength (energy absorption) as the sutures of an open wound treated by saline, while the sutures of an open wound treated by Varidase tended to have a decreased strength (p = 0.08). This study supports the hypothesis that an enzymatic process may be involved in the degradation of Dexon. The continuous use of Varidase in Dexon-sutured wounds for a period longer than a few days is, therefore, questioned.