Abstract
Introduction
Negative Pressure Wound Therapy (NPWT) is a well-established procedure used for non-healing wounds including burn wounds. In NPWT, a special sealed dressing of large cell foam (>400 µm) or gauze is connected to a pump. The sealed dressing acts as a conduit to pressure transfer and aids in the passive flow of fluid. Most commonly, negative pressures between -10 and -125 millimeters of mercury (mm Hg) are used. The mechanism of healing is unknown but maybe due to removal of the exudate and bacteria, and the stimulation of tissue repair through micro deformation. Reticulated foams with micron-size open cells (100 to 5µm) exerts capillary suction between 10 and 60 mm of Hg with a multilayered foam dressing. The negative pressures produced are within the range of suction by mechanical pumps. Therefore, the long-term goal our research is to examine effectiveness of Capillary Suction Devices (CSD) as a topical device in both preventing and healing complicated wounds, burn and donor site wounds. Our hypothesis is that CSD is an effective, safe and lower cost alternative to vacuum-assisted NPWT.
Methods
Yorkshire pigs received 4 surgical posterior excision wounds, measuring 2 in. by 2 in. The wounds were covered with a NPWT dressing (110 mm Hg negative pressure by a pump), CSD with capillary suctions of 30 mm Hg (CSD-30) and 60+ mm Hg (CSD-60), and a conventional gauze dressing. The wounds were measured on 2 day and then every 4 to 5 days until wounds closed. We also measured and compared the total fluids collected with each dressing.
Results
By post-wound day 20, the wounds treated with CSD-60 and NPWT were 100% closed while the wounds treated with CSD-30 and gauze were 65 and 45%, respectively. This indicated comparable wound closure efficacies for CSD-60 and NPWT. The CSD-30 product was superior to gauze, but less efficacious than the tested NPWT protocol. The average total fluid uptake measured in grams dry weight were similar for CSD-60 and NPWT, 36 and 38g., respectively while the values were 24g for CSD-30 and 12g for gauze. However, the maximum fluid uptake observed at day 2 indicated that CSD-60 and CSD 30, 24 and 14g respectively, were superior to NPWT and gauze 12 and 7g respectively.
Conclusions
This data indicates comparable wound closure efficacies for CSD-60 capillary suction and NPWT. The CSD product with 30 mmHg suction was superior to gauze, but less efficacious than NPWT or CSD-60 protocol. The study results provide impetus for further research on the use of high suction CSD for replacement of pump mediated NPWT and the moderate suction CSD for preventing progression of high-risk wounds to an ulcerous stage.
Applicability of Research to Practice
This small study suggests that CSD maybe alternative in to NPWT. CSD provides a significant cost and weight advantage to the patient, as well is allowing for increased mobility.
Negative pressure wound therapy: Potential publication bias caused by lack of access to unpublished study results data
