LAUSR

In peripheral artery disease (PAD), arterial blood flow to the extremities is impeded. Clinically, the severity of PAD ranges from asymptomatic disease to intermittent claudication or atypical extremity pain during exercise, and to critical limb ischemia characterized by rest-pain, tissue loss, and gangrene. Patients with PAD have an increased risk of cardiovascular morbidity and mortality, and the treatment strategy consists of cardiovascular risk modifying treatments, and treatment of leg symptoms. Exposure of the affected leg to cyclic pressure changes increases the macroand microcirculatory blood flow and may be used for the treatment of PAD [1,2]. The principles of this treatment have been described since he early 20 century, however, has more recently become a treatment option for selected patients, as a new treatment device has been developed [3–5]. FlowOx 2.0 is a CE-marked medical device designed to apply intermittent negative pressure (INP) to the extremity to improve arterial and skin blood flow. The foot and lower leg are treated in a pressure chamber made of hard Polyethylene Plastics (Figure 1). The foot arch rests on a positioner in the bottom of the pressure chamber, that is movable to adjust the lower leg’s angle inside the pressure chamber. A padding between the pressure chamber and the lower leg becomes inflated when INP is started. The pressure chamber is sealed around the lower leg below the knee using a customized thermoplastic elastomer seal. A pump unit generates INP by removing air from and venting the pressure chamber in cycles of 10 s of −40 mmHg negative pressure and 7 s of atmospheric pressure. The FlowOx device is made of lightweight components (control unit 3 kg, pressure chamber 2.5 kg) making the system mobile, and can easily be operated by most patients at home. The physiological, clinical, and health-economic implications of FlowOx treatment have been investigated in multiple studies (Table 1).