Obtaining the kidney according to the type of transplant

Anyone who wants to become a living donor must undergo a series of tests: a medical check-up, a complete analysis with serologies and determination of the blood group, and imaging tests, among which the most important may be a CT angiogram which is used to study the anatomy of the kidneys.   

In general, the left kidney is removed because it allows a longer vein to be obtained, which facilitates the transplant surgery. In cases where there are kidney abnormalities, the worst kidney is always removed. In addition, an organ with single vessels is preferred. Kidneys usually have a renal artery originating in the abdominal aorta; however, it is not uncommon to find renal arterial variations meaning that kidneys may sometimes present multiple irrigation.  Nonetheless, the presentation of multiple vessels or having to extract the right kidney does not represent a contraindication for donation.  

The surgical technique used for renal extraction is laparoscopy. To perform this technique, small incisions are made in the abdomen to introduce plastic tubes (trocars) through which the instruments are introduced. Once the kidney has been dissected, clips are placed on the renal artery and vein, for their later sectioning. The organ is quickly removed, and the donor’s blood is cleansed with a preservative fluid through the renal artery.  

The organ may be removed through an incision at the level of the navel or lower abdomen or, in the case of women, through an incision in the vaginal vault. Once this procedure is completed, the kidney is prepared for immediate grafting.  

To perform kidney extraction from a deceased donor, a cross incision is made in the abdominal wall, or a middle incision is made between the xiphoid (cartilage at the end of the sternum) and the pubis. Depending on the type of donor, more or fewer organs are removed. In the case of extraction of only the kidneys, a cannula is inserted at the level of the aorta artery to perfuse the organs with a preservative fluid and, thus, preserve their function. The blood is collected through another cannula, at the level of the vena cava.

Subsequently, the kidneys are extracted and prepared for transplantation. This preparation is called bench surgery, during which the surgeon removes the fat from around the kidneys, inspects the organ for abnormalities, and prepares the vessels for transplantation.