Influence of Negative-Pressure Wound Therapy on Tissue Oxygenation of the Foot

Abstract

BackgroundNegative-pressure wound therapy (NPWT) is believed to accelerate wound healing by altering wound microvascular blood flow. Although many studies using laser Doppler have found that NPWT increases perfusion, recent work using other modalities has demonstrated that perfusion is reduced. The purpose of this study was to investigate the influence of NPWT on tissue oxygenation of the foot, which is the most sensitive region of the body to ischemia.MethodsTranscutaneous partial pressure of oxygen (TcpO2) was used to determine perfusion beneath NPWT dressings of 10 healthy feet. The sensor was placed on the tarso-metatarsal area of the foot and the NPWT dressing was placed above the sensor. TcpO2 was measured until it reached a steady plateau state. The readings obtained at the suction-on period were compared with the initial baseline (pre-suction) readings.ResultsTcpO2 decreased significantly immediately after applying NPWT, but gradually increased over time until reaching a steady plateau state. The decrease in TcpO2 from baseline to the steady state was 2.9 to 13.9 mm Hg (mean, 9.3±3.6 mm Hg; 13.5±5.8%; P<0.01). All feet reached a plateau within 20 to 65 minutes after suction was applied.ConclusionsNPWT significantly decrease tissue oxygenation of the foot by 2.9 to 13.9 mm Hg. NPWT should be used with caution on feet that do not have adequate tissue oxygenation for wound healing.

The acute effects of lower limb intermittent negative pressure on foot macro- and microcirculation in patients with peripheral arterial disease

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Intermittent negative pressure applied to the lower limb increases foot macrocirculatory and microcirculatory blood flow pulsatility in people with spinal cord injury

“…Further, Skagen et al [26] found that constant negative pressure applied to the skin resulted in increased vascular resistance and a pronounced decrease in skin blood flow. Accordingly, NPWT decreases tissue perfusion beneath the wound dressing [36] and in close proximity to the wound area [37] and decreases tissue oxygenation of the foot [38,39].…”

The effects of intermittent negative pressure on the lower extremities' peripheral circulation and wound healing in four patients with lower limb ischemia and hard‐to‐heal leg ulcers: a case report

“…A common method used to treat acute and chronic wounds is topical negative pressure wound therapy (NPWT) where a pump applies continuous or intermittently negative pressure to a sealed dressing in the wound area, removing wound exudate from the exposed area into a canister (Dumville et al 2016). Unfortunately, the use of NPWT in the local wound environment and its impact on healing of arterial leg ulcers and tissue perfusion in clinical use are inconclusive (Wackenfors et al 2004;Gregor et al 2008;Vig et al 2011;Shon et al 2014).…”