Dispersion method of excessive portal hypertension (shear stress) and changes of portal pressure and flow after living-related liver transplantation with a splenorenal shunt: a case report

Method for spontaneous constriction and closure of portocaval shunt using a ligamentum teres hepatis in small-for-size graft liver transplantation

BACKGROUND

We have developed a new portocaval (PC) shunt creation technique for use in small-for-size (SFS) graft liver transplantations. PC shunts are already used to avoid SFS graft syndrome in cases of adult-to-adult living donor liver transplantation (LDLT), but the current method of creating these shunts is subject to two problems: reportal hypertension and liver dysfunction after premature ligation of the PC shunt; and graft atrophy and liver dysfunction because of the loss of portal venous flow late in the recovery period after LDLT.

METHODS

Our new technique avoids these two problems simultaneously by using the interposed obliterated ligamentum teres hepatis (LTH) to create the PC shunt, then obstructing the PC shunt after regeneration of the liver graft.

RESULTS

We have used this technique in four cases. In all cases, portal venous pressures after shunting were lower than those before shunting, and PC shunts with lower portal pressure were obstructed faster than that with higher portal pressure.

CONCLUSION

Our results suggest that the LTH can function as a shape memory graft to reduce portal venous flow after regeneration of the graft liver. Using the LTH to create a PC shunt might help to prevent both SFS graft syndrome early in the recovery period after LDLT and loss of portal venous flow late in the recovery period.

Management of Major Portosystemic Shunting in Small-for-Size Adult Living-Related Donor Liver Transplantation with a Left-Sided Graft Liver

PURPOSE

We investigated the mechanisms of small-for-size graft syndrome by time-lag ligation, a novel approach to treating major portosystemic shunts in small-for-size adult living-related donor liver transplantation (LRDLT) using left-sided graft liver.

METHODS

Five patients with end-stage liver failure and major splenorenal shunting underwent LRDLT using left lobe grafts. The average graft volume to recipient body weight (GV/RBW) ratio was 0.68 +/- 0.14. Two patients underwent time-lag ligation of their splenorenal (SR) shunts on postoperative days (PODs) 8 and 14, respectively. The shunts of the other three patients were untreated.

RESULTS

The portal pressures in the first patient who underwent time-lag ligation rose above 300 mmH(2)O and remained there for 2 weeks. Thus, we ligated the SR shunt in the second patient on POD 14, resulting in an increase from 177 mmH(2)O to 258 mmH(2)O, but it decreased again thereafter. In the other three patients, the SR shunt was not ligated because portal blood flow volumes remained sufficient. Total bilirubin levels in the first time-lag ligation patient rose to 16 mg/dl, paralleling the rise in portal pressures. Although they increased after ligation in the second patient, they did not exceed 10 mg/dl.

CONCLUSIONS

We recommend time-lag ligation if portal venous blood flow decreases in the early post-transplant period, but not until at least 2 weeks after transplantation. If the portal venous blood flow does not decrease, early postoperative ligation is unnecessary. If there are no major portosystemic shunts, making a portosystemic shunt might decompress excessive portal hypertension. With donor safety priority in LRDLT, novel approaches must be developed to enable the use of smaller donor grafts. We describe a potential means of using left lobe grafts in adult LRDLT.