Preoperative training of pigs used for kidney transplantation research : refinement of postoperative procedure

Abstract: The use of pigs as a preclinical model has increased dramatically the last decades. The specie´s unique anatomy and physiological features make it an appropriate transplantation study model for humans. In human medicine, kidney transplants have been established as the best and most cost-effective treatment for people with end-stage renal failure. To improve the outcome of renal transplantation in humans, the graft survival rate needs to be improved and an animal model is essential for this research. However, information regarding preoperative training to allow for stress- and pain-free repeated blood sampling as well as blood sampling techniques and measurement of the urine volume postoperatively to kidney transplantation is limited. Eight Swedish high-health domestic pigs were included in a training program in which touching and brushing the ears, ultrasound of the urinary bladder and physical examinations were performed for 15 minutes per pig every day for two weeks before transplantation surgery. Six of eight pigs underwent kidney transplantation and insertion of a catheter in the auricular vein with the Seldinger technique. After surgery, the pigs were kept for five days and blood sampling and ultrasound of the urinary bladder were performed daily. The effect of the preoperative training on postoperative examinations were evaluated. The transplantation surgery and the anaesthesia were successful and the pigs recovered well after surgery. The training period of two weeks was sufficient to enable blood sampling and ultrasound examination of the urinary bladder without restrain. Furthermore, placement of a catheter with the Seldinger technique in the auricular vein was successful and withdrawal of blood was possible in four out of six pigs for five days post-surgery. In conclusion this study shows that the pig can be trained preoperatively to accept interventions and measurements postoperatively, which makes the pig a suitable animal model in transplantation studies.