Renal vein extension in right kidney transplantation.

OBJECTIVES: The right renal vein (RRV) may be difficult to anastomose in right cadaveric kidney transplantation, especially in obese recipients in whom iliac vessels are deep. In this study, gain of length and feasibility in the presence of vascular variations obtained with three common techniques of renal vein augmentation--clamshell (CS), transverse closure of the inferior vena cava (TC), and cava conduit (CC)--were analyzed and compared to the Carrel-patch technique. METHODS: The renal vasculature and the inferior vena cava of 119 cadavers were accurately dissected and measured, and the vascular variations documented. The CS technique augmented the RRV at most by one fourth, the TC by one half the diameter of the inferior vena cava, and the CC by the length of the infrarenal inferior vena cava. An experienced transplant surgeon evaluated the situs for the feasibility of the techniques. RESULTS: The variations found were multiple veins (right, 23%; left, 6.7%), a retroaortal left vein (2.5%), a renal collar (6%); and multiple arteries (right, 20.2%; left, 19%). The RRV length varied from 21 to 71 mm, and the right renal artery (RRA) length varied between 44 and 111 mm. The RRA/RRV ratios ranged between 3.4 and 1.2. The achieved gains of length were 129% with the CS (possible in 81.5%), 190% with the TC (possible in 62.4%), and 388.4% with the CC (possible in 80.7%). CONCLUSIONS: The median RRV is one half the RRA in length so that length augmentation could be an advantage. Anatomic variations limit the choice of technique. Overall, augmentation was possible in 80%; the CS technique seldom resulted in a length equal to that of the RRA, the TC was the most susceptible to variations, and the CC always surpassed the RRA in length. Harvesting the RRV en bloc with the inferior vena cava enables the surgeon to best adapt donor vessels to the recipient's anatomy.