MEASUREMENT OF PORTAL VENOUS FLOW VELOCITY WITH AN IMPLANTABLE MINIATURE DOPPLER PROBE IN PIG-LIVER TRANSPLANTATION

Portal venous flow (PVF) was serially monitored after pig liver transp lantation (LTX) with the use of an implantable, miniature Doppler prob e developed in our laboratory Throughout the study period, the mean PV F in pigs that underwent LTX was significantly greater than that in pi gs that were sham operated. For three animals with early graft failure secondary to primary nonfunction and for six that survived longer tha n 7 days, the mean PVF on postoperative day (POD) 1 was 18.7 +/- 3.5 c m/s and 41.7 +/- 11.2 cm/s, respectively (P < 0.05). For animals with acute cellular rejection (ACR) the mean PVF was 61.3 +/- 9.9 cm/s on P OD 7 and 54.3 +/- 6.38 cm/s on POD 14. These values were significantly higher than those for animals without ACR (P < 0.05). Moreover, the i ncrease in PVF correlated well with the degree of ACR. The actual PVF volume was measured by ex vivo perfusion, which showed a clear correla tion with the PVF velocity obtained with the implanted, miniature Dopp ler probe. We feel that the liver graft requires increased PVF volume after transplantation to facilitate functional recovery from damage to hepatocytes due to preservation-reperfusion injury, and that ACR is a lso associated with an increased PVE We conclude that monitoring the P VF in the early postoperative period after LTX is useful in the evalua tion of graft function, particularly for predicting primary nonfunctio n and severity of ACR.