Gravitational retrograde venous perfusion--a technique for limb extremity salvage when microvascular arterial repair is not possible.

Occasionally in plastic surgery immediate microvascular arterial repair is not possible. This occurs when distal vessels in the extremities are extensively damaged or thrombosed. If there is some intact venous anatomy it may be possible to maintain adequate perfusion for viability using a gravitational retrograde venous perfusion technique, until collateral arterial supply develops. We have used this technique successfully in three cases--blast injury to the hand, extensive digital thromboembolism and a devascularised sole of foot. This technique involves elevating and lowering the limb at 30 min intervals for 5-7 days. Elevation results in venous drainage and pallor of the limb and dependency results in venous congestion confirming retrograde venous flow. In the authors' experience ischaemic necrosis was inevitable in these cases without the use of this new technique. We have attempted to explain this phenomenon by way of retrograde venous perfusion in association with high venous pressure and high oxygen tension.