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Split Liver Transplantation
Split Liver Transplantation H. Yersiz, A.M. Cameron, I. Carmody, M.A. Zimmerman, B.S. Kelly, Jr, R.M. Ghobrial, D.G. Farmer, and R.W. Busuttil ABSTRACT Seventy-five thousand Americans develop organ failure each year. Fifteen percent of those on the list for transplantation die while waiting. Several possible mechanisms to expand the organ pool are being pursued including the use of extended criteria donors, living donation, and split deceased donor transplants. Cadaveric organ splitting results from improved understanding of the surgical anatomy of the liver derived from Couinaud. Early efforts focused on reduced-liver transplantation (RLT) reported by both Bismuth and Broelsch in the mid-1980s. These techniques were soon modified to create both a left lateral segment graft appropriate for a pediatric recipient and a right trisegment for an appropriately sized adult. Techniques of split liver transplantation (SLT) were also modified to create living donor liver transplantation. Pichlmayr and Bismuth reported successful split liver transplantation in 1989 and Emond reported a larger series of nine split procedures in 1990. Broelsch and Busuttil described a technical modification in which the split was performed in situ at the donor institution with surgical division completed in the heart beating cadaveric donor. In situ splitting reduces cold ischemia, simplifies identification of biliary and vascular structures, and reduces reperfusion hemorrhage. However, in situ splits require specialized skills, prolonged operating room time, and increased logistical coordination at the donor institution. At UCLA over 120 in situ splits have been performed and this technique is the default when an optimal donor is available. Split liver transplantation now accounts for 10% of adult transplantations at UCLA and 40% of pediatric transplantations.
T
HE ANATOMIC BASIS of splitting a cadaveric organ to transplant two recipients comes from the work of Couinaud.1 Early efforts focused on the surgical reduction of adult cadaveric grafts, termed reduced-liver transplantation (RLT). Initially plagued by technical difficulties, RLT later showed results equal to or superior to pediatric whole grafts. These techniques were soon modified to create both a left lateral segment graft appropriate for a pediatric recipient and a right trisegment for an appropriately sized adult. Pichlmayr2 and Bismuth3 both reported successful split liver transplantation (SLT) in 1989 and Emond4 reported a larger series of nine split procedures from the University of Chicago in 1990. TECHNIQUE: CREATION OF A LEFT LATERAL SEGMENT GRAFT AND RIGHT TRISEGMENT GRAFT The left hepatic vein is identified, isolated, and encircled with a vessel loop. Next, hilar dissection begins at the base of the round ligament with isolation of the left hepatic artery, left portal vein, and left hepatic duct. With vascular control of the left lateral 0041-1345/06/$–see front matter doi:10.1016/j.transproceed.2005.12.064 602
segment obtained parenchymal transection is initiated. The liver is scored with the electrocautery approximately 1 cm to the right of the falciform ligament. The parenchyma is divided between the left lateral segment and segment 4 and carried to 1 cm above the left bile duct in the umbilical fissure. The left hilar plate containing the bile duct is sharply transected. The left lateral segment is now separate from the rest of the parenchyma with its own vascular pedicle and venous drainage. Following organ cold perfusion the left hepaticartery, left portal vein, and left hepatic vein are sharply divided. The left bile duct is flushed with cold University of Wisconsin (UW) solution and stored in the standard fashion. The
From the Division of Liver and Pancreas Transplantation, Department of Surgery, David Geffen School of Medicine at UCLA, Los Angeles, California, USA. Address reprint requests to Hasan Yersiz, MD, Division of Liver and Pancreas Transplantation, David Geffen School of Medicine at UCLA, 650 C.E. Young Drive, South, 77-120 CHS, Box 957054, Los Angeles, CA 90095-7054. E-mail: hyersiz@ mednet.ucla.edu © 2006 by Elsevier Inc. All rights reserved. 360 Park Avenue South, New York, NY 10010-1710 Transplantation Proceedings, 38, 602– 603 (2006)
SPLIT LIVER TRANSPLANTATION right trisegment graft is removed in the standard fashion and stored in cold UW solution. Transplantation of the left lateral segment requires preservation of the recipient vena cava (“piggybacking”). Biliary anastomosis may be duct-to-duct, but more commonly is accomplished with Roux-en-Y reconstruction. Preparation of the right trisegment graft requires closure of the left hepatic vein, left portal vein, and left hepatic artery origins. Oversewing of the left hepatic duct remnant is likewise required. The cut edge parenchymal edge is carefully inspected for vascular or biliary leaks which are oversewn.
PUBLISHED RESULTS
Adult– child SLT expanded during the late 1990s with several centers reporting individual experiences of up to 78 splits. Complication rates remained high (30%) with biliary problems being the most common. Graft sharing was reported but remained infrequent, accounting for 5% of total grafts. More recently, Renz et al5 reported on ASTS survey data collected on SLT. Data were obtained on 215 SLTs performed in the United States from 1994 through 2001. Forty-two of these were in situ procedures, 140 ex vivo, and 33 partial procedures. Graft failure was seen in 32% of recipients, with death in 26%. When compared with historic control recipients, results were generally comparable to “extended criteria” whole organ recipients and inferior to recipients who received organs from “optimal” donors ages 18 to 40 years. UNOS status 1 recipients fared the worst when receiving a split right lobe graft. Less has been published on adult–adult SLT. The early experience from Chicago yielded patient and graft survival rates of 67% and 50%, respectively, lower than those of whole graft recipients. Paul Brousse reports on the largest series of splitting for 2 adult recipients with 27 SLTs that gave an approximately 80% 1-year graft survival rate.6,7 These procedures were done ex vivo and a 22% biliary complication rate was reported with one incidence of primary nonfunction. Biliary complications were more likely to occur in the left lobe graft and arterial complications in the right. Smaller North American series from Humar et al and others have given similar results. THE UCLA SLT EXPERIENCE
The UCLA series of conventional SLT has reached 110. This series shows outcome results comparable to those seen with whole organ transplantation. Specifically, a retrospective analysis of SLTs occurring from 1991 through 2003 documented 100 SLTs which generated transplants for 105 pediatric recipients and 60 adult recipients with sharing of 25 allografts with other centers across the United States.8 The incidence of biliary and vascular complications in
603
recipients of left lateral segment grafts created by splitting was statistically no different than that seen with a historic control group of living donor left lateral segment grafts or pediatric whole graft recipients. Graft and recipient survival rates were also no different between these groups. Adult right trisegment graft recipients in this series showed a 10% rate of biliary complications and 7% incidence of vascular complications. Long-term graft function was excellent with patient and graft survival rates equal to a control group that received cadaveric whole grafts from “optimal” donors ages 10 to 40 years. Predictors of graft and recipient survival were analyzed and showed an effect determined by UNOS status 1, indication for transplantation, as well as donor creatinine and length of hospitalization. SUMMARY
Left lateral segment SLT grafts demonstrate long-term graft and patient survival equal to living donor and whole organ outcomes in children with a slightly increased incidence of complications. Right trisegment SLT grafts demonstrate equal or better graft and patient survival to whole grafts. Split liver transplantation offers immediate expansion of the donor pool. Split liver grafts exhibit outcomes similar to cadaveric whole organs with a slightly higher incidence of complications. The routine application of SLT can dramatically decrease dependency upon living donation. It is a technically challenging operation requiring both meticulous surgery and patient selection. REFERENCES 1. Couinaud C: Le Foie: Etudes Anatomiques et Chirurgicales. Paris: Masson, 1957. 2. Pichlmayr R, Ringe B, Gubernatis G: Transplantation of a donor liver to 2 recipients (splitting transplantation)—a new method in the further development of segmental liver transplantation. Langenbecks Archiv Chir 373:127, 1989 3. Bismuth H, Morino M, Castaing D, et al: Emergency orthotopic liver transplantation in two patients using one donor liver. Br J Surg 76:722, 1989 4. Emond JC, Whitington PF, Thistlethwaite JR, et al: Transplantation of two patients with one liver. Analysis of a preliminary experience with “split-liver” grafting. Ann Surg 212:14, 1990 5. Renz JF, Emond JC, Yersiz H, et al: Split-liver transplantation in the United States: outcomes of a national survey. Ann Surg 239:172, 2004 6. Azoulay D, Castaing D, Adam R, et al: Split liver transplantation for two adult recipients: feasibility and long term outcomes. Ann Surg 233:565, 2001 7. Humar A, Kandaswamy R, Sielaff T, et al: Split Liver Transplants for 2 adult recipients: an initial experience. ATC, Transplant 2001, Chicago IL. May 12–16, 2001 8. Yersiz H, Renz JF, Farmer DG, et al: One hundred in situ split liver transplantations: a single center experience. Ann Surg 238:496, 2003
T
HE ANATOMIC BASIS of splitting a cadaveric organ to transplant two recipients comes from the work of Couinaud.1 Early efforts focused on the surgical reduction of adult cadaveric grafts, termed reduced-liver transplantation (RLT). Initially plagued by technical difficulties, RLT later showed results equal to or superior to pediatric whole grafts. These techniques were soon modified to create both a left lateral segment graft appropriate for a pediatric recipient and a right trisegment for an appropriately sized adult. Pichlmayr2 and Bismuth3 both reported successful split liver transplantation (SLT) in 1989 and Emond4 reported a larger series of nine split procedures from the University of Chicago in 1990. TECHNIQUE: CREATION OF A LEFT LATERAL SEGMENT GRAFT AND RIGHT TRISEGMENT GRAFT The left hepatic vein is identified, isolated, and encircled with a vessel loop. Next, hilar dissection begins at the base of the round ligament with isolation of the left hepatic artery, left portal vein, and left hepatic duct. With vascular control of the left lateral 0041-1345/06/$–see front matter doi:10.1016/j.transproceed.2005.12.064 602
segment obtained parenchymal transection is initiated. The liver is scored with the electrocautery approximately 1 cm to the right of the falciform ligament. The parenchyma is divided between the left lateral segment and segment 4 and carried to 1 cm above the left bile duct in the umbilical fissure. The left hilar plate containing the bile duct is sharply transected. The left lateral segment is now separate from the rest of the parenchyma with its own vascular pedicle and venous drainage. Following organ cold perfusion the left hepaticartery, left portal vein, and left hepatic vein are sharply divided. The left bile duct is flushed with cold University of Wisconsin (UW) solution and stored in the standard fashion. The
From the Division of Liver and Pancreas Transplantation, Department of Surgery, David Geffen School of Medicine at UCLA, Los Angeles, California, USA. Address reprint requests to Hasan Yersiz, MD, Division of Liver and Pancreas Transplantation, David Geffen School of Medicine at UCLA, 650 C.E. Young Drive, South, 77-120 CHS, Box 957054, Los Angeles, CA 90095-7054. E-mail: hyersiz@ mednet.ucla.edu © 2006 by Elsevier Inc. All rights reserved. 360 Park Avenue South, New York, NY 10010-1710 Transplantation Proceedings, 38, 602– 603 (2006)
SPLIT LIVER TRANSPLANTATION right trisegment graft is removed in the standard fashion and stored in cold UW solution. Transplantation of the left lateral segment requires preservation of the recipient vena cava (“piggybacking”). Biliary anastomosis may be duct-to-duct, but more commonly is accomplished with Roux-en-Y reconstruction. Preparation of the right trisegment graft requires closure of the left hepatic vein, left portal vein, and left hepatic artery origins. Oversewing of the left hepatic duct remnant is likewise required. The cut edge parenchymal edge is carefully inspected for vascular or biliary leaks which are oversewn.
PUBLISHED RESULTS
Adult– child SLT expanded during the late 1990s with several centers reporting individual experiences of up to 78 splits. Complication rates remained high (30%) with biliary problems being the most common. Graft sharing was reported but remained infrequent, accounting for 5% of total grafts. More recently, Renz et al5 reported on ASTS survey data collected on SLT. Data were obtained on 215 SLTs performed in the United States from 1994 through 2001. Forty-two of these were in situ procedures, 140 ex vivo, and 33 partial procedures. Graft failure was seen in 32% of recipients, with death in 26%. When compared with historic control recipients, results were generally comparable to “extended criteria” whole organ recipients and inferior to recipients who received organs from “optimal” donors ages 18 to 40 years. UNOS status 1 recipients fared the worst when receiving a split right lobe graft. Less has been published on adult–adult SLT. The early experience from Chicago yielded patient and graft survival rates of 67% and 50%, respectively, lower than those of whole graft recipients. Paul Brousse reports on the largest series of splitting for 2 adult recipients with 27 SLTs that gave an approximately 80% 1-year graft survival rate.6,7 These procedures were done ex vivo and a 22% biliary complication rate was reported with one incidence of primary nonfunction. Biliary complications were more likely to occur in the left lobe graft and arterial complications in the right. Smaller North American series from Humar et al and others have given similar results. THE UCLA SLT EXPERIENCE
The UCLA series of conventional SLT has reached 110. This series shows outcome results comparable to those seen with whole organ transplantation. Specifically, a retrospective analysis of SLTs occurring from 1991 through 2003 documented 100 SLTs which generated transplants for 105 pediatric recipients and 60 adult recipients with sharing of 25 allografts with other centers across the United States.8 The incidence of biliary and vascular complications in
603
recipients of left lateral segment grafts created by splitting was statistically no different than that seen with a historic control group of living donor left lateral segment grafts or pediatric whole graft recipients. Graft and recipient survival rates were also no different between these groups. Adult right trisegment graft recipients in this series showed a 10% rate of biliary complications and 7% incidence of vascular complications. Long-term graft function was excellent with patient and graft survival rates equal to a control group that received cadaveric whole grafts from “optimal” donors ages 10 to 40 years. Predictors of graft and recipient survival were analyzed and showed an effect determined by UNOS status 1, indication for transplantation, as well as donor creatinine and length of hospitalization. SUMMARY
Left lateral segment SLT grafts demonstrate long-term graft and patient survival equal to living donor and whole organ outcomes in children with a slightly increased incidence of complications. Right trisegment SLT grafts demonstrate equal or better graft and patient survival to whole grafts. Split liver transplantation offers immediate expansion of the donor pool. Split liver grafts exhibit outcomes similar to cadaveric whole organs with a slightly higher incidence of complications. The routine application of SLT can dramatically decrease dependency upon living donation. It is a technically challenging operation requiring both meticulous surgery and patient selection. REFERENCES 1. Couinaud C: Le Foie: Etudes Anatomiques et Chirurgicales. Paris: Masson, 1957. 2. Pichlmayr R, Ringe B, Gubernatis G: Transplantation of a donor liver to 2 recipients (splitting transplantation)—a new method in the further development of segmental liver transplantation. Langenbecks Archiv Chir 373:127, 1989 3. Bismuth H, Morino M, Castaing D, et al: Emergency orthotopic liver transplantation in two patients using one donor liver. Br J Surg 76:722, 1989 4. Emond JC, Whitington PF, Thistlethwaite JR, et al: Transplantation of two patients with one liver. Analysis of a preliminary experience with “split-liver” grafting. Ann Surg 212:14, 1990 5. Renz JF, Emond JC, Yersiz H, et al: Split-liver transplantation in the United States: outcomes of a national survey. Ann Surg 239:172, 2004 6. Azoulay D, Castaing D, Adam R, et al: Split liver transplantation for two adult recipients: feasibility and long term outcomes. Ann Surg 233:565, 2001 7. Humar A, Kandaswamy R, Sielaff T, et al: Split Liver Transplants for 2 adult recipients: an initial experience. ATC, Transplant 2001, Chicago IL. May 12–16, 2001 8. Yersiz H, Renz JF, Farmer DG, et al: One hundred in situ split liver transplantations: a single center experience. Ann Surg 238:496, 2003