The influence of different sizes and types of wound fillers on wound contraction and tissue pressure during negative pressure wound therapy

Abstract

Negative pressure wound therapy (NPWT) contracts the wound and alters the pressure in the tissue of the wound edge, which accelerates wound healing. The aim of this study was to examine the effect of the type (foam or gauze) and size (small or large) of wound filler for NPWT on wound contraction and tissue pressure. Negative pressures between --20 and --160 mmHg were applied to a peripheral porcine wound (n = 8). The pressure in the wound edge tissue was measured at distances of 0·1, 0·5, 1·0 and 2·0 cm from the wound edge and the wound diameter was determined. At 0·1 cm from the wound edge, the tissue pressure decreased when NPWT was applied, whereas at 0·5 cm it increased. Tissue pressure was not affected at 1·0 or 2·0 cm from the wound edge. The tissue pressure, at 0·5 cm from the wound edge, was greater when using a small foam than when using than a large foam. Wound contraction was greater when using a small foam than when using a large foam during NPWT. Gauze resulted in an intermediate wound contraction that was not affected by the size of the gauze filler. The use of a small foam to fill the wound causes considerable wound contraction and may thus be used when maximal mechanical stress and granulation tissue formation are desirable. Gauze or large amounts of foam result in less wound contraction which may be beneficial, for example when NPWT causes pain to the patient.

Letter: The influence of different sizes and types of wound fillers on wound contraction and tissue pressure during negative pressure wound therapy.

“…Although our processed meat experiments demonstrated that tissue pressure increased during NPWT for up to 3 cm from the dressing (2), we too found that this pressure dissipated more rapidly in human tissues (unpublished data), in keeping with Anesäter et al (1) In most instances we found that there was very little increase in tissue pressure beyond 1 cm, although this distance varied in different wounds (unpublished data).…”

“…We congratulate the researchers from the Lund group, who have added yet another building block to our knowledge of the mechanism of action of negative pressure wound therapy (NPWT) with their article titled ‘The influence of different sizes and types of wound fillers on wound contraction and tissue pressure during negative pressure wound therapy’ by Anesäter et al (1).…”

Extended negative pressure wound therapy-assisted dermatotraction for the closure of large open fasciotomy wounds in necrotizing fasciitis patients

“…However, increased tissue pressure by extended NPWT reduced over 48 hours of application, as it was non-circumferential [20]. Moreover, the sponges in the wound cavity limited the wound contraction by the NPWT [26]. To approximate the longitudinal fasciotomy wound further, we applied the dermatotraction at both skin margins under the NPWT sponge.…”

“…To approximate the longitudinal fasciotomy wound further, we applied the dermatotraction at both skin margins under the NPWT sponge. The dermatotraction vessel loop pull the both skin margins continuously, allowing stress relaxation of the contracted skin and preventing the NPWT sponge from filling the wound cavity, thus maximizing wound contraction by NPWT [26]. In this way, the dermatotraction acted as an elastic corset lacing.…”

The effect of regional block over pain levels during vacuum‐assisted wound closure

“…Even though the moist environment VAWC provides may appear to alleviate pain during dressing changes, the migration of granulation tissue into the foam results in a high level of pain during its removal (4,5). The negative pressure creates a force that contracts the wound edges towards the centre which also may cause a great deal of pain for a group of patients especially in the first few days of treatment (1,2,6,7).…”