Biological effects of a disposable, canisterless negative pressure wound therapy system

Malin Malmsjö, Elizabeth Huddleston, Robin Martin, Malin Malmsjö, Elizabeth Huddleston, Robin Martin

Abstract

Objective: Recent developments of negative pressure wound therapy (NPWT) systems have focused on making pumps smaller, lighter, and more portable. The recently introduced PICO system manages wound fluid through a highly breathable film within the dressing, thereby negating the need for a canister, which allows greater mobility and patient concordance. The aim of this study is to compare the biological effects of this system compared to a traditional NPWT system.

Methods: Laboratory tests were carried out to demonstrate the fluid handling properties of the PICO™ system. Porcine full thickness defect wounds and sutured incisional wounds were used to compare the biological effects. Wounds were treated with PICO dressings or traditional NPWT dressings and connected to either a PICO device or a traditional NPWT device.

Results: The PICO dressing manages exudate predominantly through evaporative loss (up to 85% of all fluid entering the dressing). Both traditional NPWT and the PICO system maintained therapeutic levels of negative pressure in all wounds. Both NPWT systems produced similar effects on wound edge contraction and microvascular blood flow in defect wounds. No significant changes in blood flow or wound contraction were noted in incision wounds for any NPWT combinations tested.

Conclusions: The disposable, canisterless PICO NPWT system functions in the same manner as the traditional NPWT systems with regard to fluid handling, pressure transmission to the wound bed, tissue contraction, and changes in blood flow.

Keywords: Blood flow; NPWT; dressing; vacuum; wound.

Figures

Figure 1
Figure 1
The structure and working principles of the PICO™ dressing. The PICO system simplifies NPWT by replacing the exudate canister with an absorbent dressing that has a high evaporative loss. The top panel illustrates wound exudate removal through the dressing. The PICO dressing is absorbent and is composed of 4 layers, as follows. The wound contact layer is a perforated flexible silicone adhesive layer, bonded to a lower airlock layer and an upper fluid absorption layer that delivers negative pressure, removes wound exudate, and aids evaporation of fluid through the high moisture vapor transmission rate upper film layer. The bottom panel is a scanning electron micrograph cross-section through a PICO dressing showing the 3 lower layers.
Figure 2
Figure 2
Fluid handling properties of the PICO™ system. Fluid was pumped into an in vitro wound model covered with a PICO dressing at low exudate rate of 7.5 mL/24 h for 7 days (bottom panel) and high exudate rate 70 of mL/24 h for 45 hours (top panel). Continuous weight measurements were taken to establish how much fluid was retained in the dressing and how much fluid was lost to transpiration. A background air leak at a rate of 10 mL/min was introduced to reflect possible clinical conditions of use. Results are shown as means values of 3 experiments.
Figure 3
Figure 3
Photos of the treated wounds. Both incision and defect wounds were studied. In defect wounds, the wound cavity was either filled with polyurethane foam or gauze or left empty. The sutured incision wounds were either covered with a small piece of foam or gauze or left bare. Both wound types were then covered with either a 15 × 20 cm2 PICO™ dressing or a standard NPWT adhesive drape and wound drain. The NPWT dressings were connected either directly to a PICO prototype pump or a traditional NPWT pump set to deliver a negative pressure of −80 mm Hg. See “Methods” for details.
Figure 4
Figure 4
Pressure distribution, studied in vivo. Wounds were treated with different device, dressing and filler combinations set to provide NPWT at −80 mm Hg. The horizontal line (—) indicates the −80 mm Hg set point of the NPWT pumps. The arrow indicates the combination that represents the PICO™ system with no filler. The pressure was measured in the wound bed of defect wounds (top panel) or on top of the suture line of incisional wounds (bottom panel). Results are shown as means ± SEM of 8 experiments.
Figure 5
Figure 5
Wound contraction. Wounds were treated with different device, dressing, and filler combinations set to provide NPWT at −80 mmHg. For defect wounds, the vertical and horizontal diameters of the wound, and for incisional wounds, distance between previously defined landmarks from the wound edge, were measured before and after the application of negative pressure and the mean value of the percent change was calculated. The arrow indicates the combination that represents the PICO™ system with no filler. Results are shown as means ± SEM of 8 experiments.
Figure 6
Figure 6
Wound edge microvascular blood flow. Wounds were treated with different device, dressing, and filler combinations set to provide NPWT at −80 mm Hg. Microvascular blood flow in the wound edge was measured using laser Doppler velocimetry before and after application of NPWT. In defect wounds, the probes were placed 0.5 cm and 2.5 cm from the wound edge. In incision wounds, the probes were placed at a depth of 0.5 cm and 2.5 cm from the skin surface, close to the incision edge. Microvascular blood flow is expressed as percentage change relative to baseline values. The arrow indicates the combination that represents the PICO™ system with no filler. Results are shown as means ± SEM of 8 experiments.

References

    1. Morykwas MJ, Argenta LC, Shelton-Brown EI, McGuirt W. Vacuum-assisted closure: a new method for wound control and treatment: animal studies and basic foundation. Ann Plast Surg. 1997;38(6):553–62.
    1. Argenta LC, Morykwas MJ. Vacuum-assisted closure: a new method for wound control and treatment: clinical experience. Ann Plast Surg. 1997;38(6):563–76. discussion 577.
    1. Borgquist O, Gustafsson L, Ingemansson R, Malmsjo M. Micro- and macromechanical effects on the wound bed of negative pressure wound therapy using gauze and foam. Ann Plast Surg. 2010;64(6):789–93.
    1. Malmsjo M, Ingemansson R, Martin R, Huddleston E. Negative-pressure wound therapy using gauze or open-cell polyurethane foam: similar early effects on pressure transduction and tissue contraction in an experimental porcine wound model. Wound Repair Regen. 2009;17(2):200–5.
    1. Chen SZ, Li J, Li XY, Xu LS. Effects of vacuum-assisted closure on wound microcirculation: an experimental study. Asian J Surg. 2005;28(3):211–7.
    1. Greene AK, Puder M, Roy R, et al. Microdeformational wound therapy: effects on angiogenesis and matrix metalloproteinases in chronic wounds of 3 debilitated patients. Ann Plast Surg. 2006;56(4):418–22.
    1. Borgquist O, Gustafsson L, Ingemansson R, Malmsjö M. Micro- and macromechanical effects on the wound bed of negative pressure wound therapy using gauze and foam. Ann Plast Surg. 2010;64(6):789–93.
    1. Sposato G, Molea G, Di Caprio G, Scioli M, La Rusca I, Ziccardi P. Ambulant vacuum-assisted closure of skin-graft dressing in the lower limbs using a portable mini-VAC device. Br J Plast Surg. 2001;54(3):235–7.
    1. Bendewald FP, Cima RR, Metcalf DR, Hassan I. Using negative pressure wound therapy following surgery for complex pilonidal disease: a case series. Ostomy Wound Manage. 2007;53(5):40–6.
    1. Landsman A. Analysis of the SNaP Wound Care System: a negative pressure wound device for treatment of diabetic lower extremity wounds. J Diabetes Sci Technol. 2010;4(4):831–2.
    1. Khanbhai M, Fosah R, Oddy MJ, Richards T. Disposable NPWT device to facilitate early patient discharge following complex DFU. J Wound Care. 2012;21(4):180, 182.
    1. Malmsjo M, Gustafsson L, Lindstedt S, Gesslein B, Ingemansson R. The effects of variable, intermittent, and continuous negative pressure wound therapy, using foam or gauze, on wound contraction, granulation tissue formation, and ingrowth into the wound filler. Eplasty. 2012;12:e5.
    1. Fraccalvieri M, Zingarelli E, Ruka E, et al. Negative pressure wound therapy using gauze and foam: histological, immunohistochemical and ultrasonography morphological analysis of the granulation tissue and scar tissue. Preliminary report of a clinical study. Int Wound J. 2011;8(4):355–64.
    1. Dorafshar AH, Mieczyslawa F, Lohman R, Gottlieb LJ. Prospective randomized study comparing gauze suction negative pressure wound therapy with standard vacuum assisted closure device; Paper presented at: the 88th Annual Meeting and Symposium of American Association of Plastic Surgeons; Rancho Mirage, CA: 2009. Mar 21–25,
    1. Malmsjo M, Ingemansson R, Martin R, Huddleston E. Wound edge microvascular blood flow: effects of negative pressure wound therapy using gauze or polyurethane foam. Ann Plast Surg. 2009;63(6):676–81.
    1. Stannard JP, Volgas DA, McGwin G, III, et al. Incisional negative pressure wound therapy after high-risk lower extremity fractures. J Orthop Trauma. 2012;26(1):37–42.
    1. Dealey C, Cameron J, Arrowsmith M. A study comparing two objective methods of quantifying the production of wound exudate. J Wound Care. 2006;15(4):149–53.
    1. Hudson DA, Adams KG, Huyssteen AV, Martin R, Huddleston EM. Simplified negative pressure wound therapy: clinical evaluation of an ultraportable, no-canister system [published online ahead of print May 7, 2013] Int Wound J. DOI: 10.1111/iwj.12080.
    1. Wilkes RP, Kilpad DV, Zhao Y, Kazala R, McNulty A. Closed incision management with negative pressure wound therapy (CIM): biomechanics. Surg Innov. 2012;19(1):67–75.
    1. Borgquist O, Anesater E, Hedstrom E, Lee CK, Ingemansson R, Malmsjo M. Measurements of wound edge microvascular blood flow during negative pressure wound therapy using thermodiffusion and transcutaneous and invasive laser Doppler velocimetry. Wound Repair Regen. 2011;19(6):727–33.
    1. Borgquist O, Ingemansson R, Malmsjo M. Wound edge microvascular blood flow during negative-pressure wound therapy: examining the effects of pressures from −10 to −175 mm Hg. Plast Reconstr Surg. 2010;125(2):502–9.
    1. Kairinos N, Solomons M, Hudson DA. The paradox of negative pressure wound therapy: in vitro studies. J Plast Reconstr Aesthet Surg. 2010;63(1):174–9.
    1. Jonsson K, Jensen JA, Goodson WHI, et al. Tissue oxygenation, anemia, and perfusion in relation to wound healing in surgical patients. Ann Surg. 1991;214(5):605–13.
    1. Petzina R, Gustafsson L, Mokhtari A, Ingemansson R, Malmsjo M. Effect of vacuum-assisted closure on blood flow in the peristernal thoracic wall after internal mammary artery harvesting. Eur J Cardiothorac Surg. 2006;30(1):85–9.
    1. Kairinos N, Voogd AM, Botha PH, et al. Negative-pressure wound therapy II: negative-pressure wound therapy and increased perfusion. Just an illusion? Plast Reconstr Surg. 2009;123(2):601–12.
    1. Venturi ML, Attinger CE, Mesbahi AN, Hess CL, Graw KS. Mechanisms and clinical applications of the vacuum-assisted closure (VAC) Device: a review. Am J Clin Dermatol. 2005;6(3):185–94.
    1. Attinger CE, Janis JE, Steinberg J, Schwartz J, Al-Attar A, Couch K. Clinical approach to wounds: debridement and wound bed preparation including the use of dressings and wound-healing adjuvants. Plast Reconstr Surg. 2006;117(7) suppl:72S–109S.
    1. Stannard JP, Robinson JT, Anderson ER, McGwin G, Jr, Volgas DA, Alonso JE. Negative pressure wound therapy to treat hematomas and surgical incisions following high-energy trauma. J Trauma. 2006;60(6):1301–6.
    1. Reddix RN, Jr, Tyler HK, Kulp B, Webb LX. Incisional vacuum-assisted wound closure in morbidly obese patients undergoing acetabular fracture surgery. Am J Orthop (Belle Mead NJ) 2009;38(9):446–9.
    1. Atkins BZ, Wooten MK, Kistler J, Hurley K, Hughes GC, Wolfe WG. Does negative pressure wound therapy have a role in preventing poststernotomy wound complications? Surg Innov. 2009;16(2):140–6.
    1. Gomoll AH, Lin A, Harris MB. Incisional vacuum-assisted closure therapy. J Orthop Trauma. 2006;20(10):705–9.
    1. Kilpadi DV, Cunningham MR. Evaluation of closed incision management with negative pressure wound therapy (CIM): hematoma/seroma and involvement of the lymphatic system. Wound Repair Regen. 2011;19(5):588–96.
    1. Karlakki S, Brem M, Giannini S, Khanduja V, Stannard J, Martin R. Negative pressure wound therapy for managementof the surgical incision in orthopaedic surgery: A review of evidence and mechanisms for an emerging indication. Bone Joint Res. 2013;2(12):276–84.

Source: PubMed

Patrocinadores y Colaboradores

Condiciones médicas

Intervenciones de drogas

3
Suscribir