Primary Use of Negative Pressure Dressings in Lower Extremity Distal Bypass Wounds

Introduction: Wound complications of leg wounds occur in up to 44% of patients after femoral distal bypass surgery. There are technical difficulties in obtaining primary wound closure especially on the anterior tibial wound, particularly in the setting of critical limb ischaemia and oedema. Technical summary: Primary use of negative pressure dressings in this situation has not been described. We describe a case report and a technique which will help obtain safe wound closure without compromising graft integrity by tunnelling the graft obliquely under the tibialis anterior muscle and then applying primary PicoTM dressing. Conclusion: By avoiding tension on fragile oedematous tissue safe wound closure may be obtained. Consent: Informed patient consent was obtained for the treatment as well as for the publication of the photograph. Journal of Cardiovascular Diseases & Diagnosis J o u r n a l o f C ar dio vas cular Dases & ia g n o s i s ISSN: 2329-9517 Citation: Ramanathan AK, Papas G (2015) Primary Use of Negative Pressure Dressings in Lower Extremity Distal Bypass Wounds. J Cardiovasc Dis Diagn 3: 228. doi:10.4172/2329-9517.1000228


Introduction
Wound complications are common and occur in 17-44% of patients after infra inguinal bypasses [1]. Many of these occur in the lower end of the wound [2], and can compromise graft integrity [3]. Wound complications may start a cascade of events that result in prolonged hospital stay, amputations and even death. Bypasses to the anterior tibial and dorsalis pedis arteries are particularly at risk.
Chronic critical limb ischemia is associated with substantial oedema of the affected limb [4]. A major portion of this is in the subcutaneous tissue but the oedema also affects the muscles [5]. Once deep fascia is incised and the muscle is released from its compartment, it tends to bulge. This makes wound approximation challenging. Avoiding tension in wound closure is important.
In our experience the anterior tibial wound is most at risk for inability to close due to tension. Our goal was to see if the use of negative pressure dressing directly over the wound that is left open will help to overcome this problem.

Case Report
A 66 year old man presented to us with rest pain of the left foot of one month duration. The patient had severe left sided weakness from a previous embolic stroke from the right internal carotid artery origin. Though he was mostly wheelchair bound he used the left leg for transfer and walking inside the house. The patient was a type 2 diabetic on oral medication. He also had hypertension and hypercholesterolemia. He did not have ischaemic heart disease. There was a past history of left sided deep vein thrombosis. He was an ex-smoker.
Examination revealed an obese patient. He was on a wheelchair but was able to transfer. He was in sinus rhythm. There was no bruit over the carotids. There was no bruit over the precordium. Examination of the abdomen was unremarkable except for a para umbilical hernia. The femoral pulses were palpable on both sides. On the left side the popliteal or the foot pulses could not be palpated. The left lower extremity was swollen and discoloured and the capillary refill was sluggish. The ankle *Corresponding author: A. Ramanathan, 1Surgical Angiology Institute, 28C, 654, Pacific Highway, Kanwal, NSW 2259, Australia, E-mail: aram02@gmail.com

Discussion
Various strategies have been used to overcome the problem of skin closure after distal bypasses in swollen limbs. Relaxing incisions with primary skin grafting have been used. Use of negative pressure therapy in vascular surgery is well documented. Negative pressure dressings on exposed infected grafts [6,7] and on wounds after skin closure [8] , have been described. Primary use of negative pressure dressings on open anterior tibial surgical wounds has not been described. By tunnelling obliquely under the tibialis anterior the muscle can be used to protect the graft from being exposed to the outside and to minimises the risk of suction injury to the graft, and to avoid exposure of the graft with risk of graft infection. excess swelling. At completion of surgery the wound is left open and the PICO dressing is applied and negative pressure of -70 mm Hg is started immediately. The bulging tibialis anterior muscle which causes skin tension becomes an ally if the tunnelling is done to have the graft run obliquely deep to the muscle once it crosses the edge of the tibia (Figure 1). The muscle then overlies the graft and the negative pressure dressing can be applied directly over it.
All wounds closed in this way have healed and have remained healed (follow up of up to 18 months) (Figure 2).