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Keywords:

  • Left lobe graft;
  • live donor transplantation;
  • portal pressure;
  • portosystemic shunt;
  • small-for size graft;
  • small-for-size syndrome

Abstract

  1. Top of page
  2. Abstract
  3. Introduction
  4. Patients and Methods
  5. Results
  6. Discussion
  7. Acknowledgments
  8. References

We developed an algorithm of graft selection in which left lobe donation is considered primarily if the graft-to-recipient weight ratio (GRWR) is estimated to be greater than 0.6% in preoperative volumetry with utilization of a hemi-portocaval shunt (HPCS) based on portal vein pressure (PVP) more than 20 mmHg at the time of laparotomy. A total of 11 consecutive adult living donor liver transplantations with small-for-size graft according to our graft selection algorithm were performed between December 2005 and August 2007. Ten patients required HPCS using a vein graft all survived without small-for-size syndrome (SFSS) and shunt complications with a median follow-up of 296 days. One patient without HPCS died of chronic vascular rejection. In all cases, PVP were regulated successfully under 20 mmHg by HPCS. Graft volume reached in mean 84.3% of standard liver volume in right lobe grafts and mean 95.4% in left lobe grafts at 3 months after liver transplantation. Actuarial rate of shunt patency at 1, 3, 6 months and 1 year were 80%, 55%, 26% and 20%, respectively. Selective HPCS based on PVP is an effective procedure and results in excellent patient and graft survival with avoidance of SFSS in grafts greater than 0.6% of GRWR.


Introduction

  1. Top of page
  2. Abstract
  3. Introduction
  4. Patients and Methods
  5. Results
  6. Discussion
  7. Acknowledgments
  8. References

Adult living donor liver transplantation (ALDLT) has been widely expanded in the world after the introduction of right lobe grafting (1–3). However, this expansion was hampered by the issues of morbidity and mortality in living donors undergoing right lobectomy (4,5). Some institutions, especially in Japan, were extending ALDLT using a left lobe graft (LLG) for selected patients (6,7).

With donor safety as a prime concern, we had utilized 39 LLGs in adult recipients. Ninety-day patient survival using LLG with less than 0.8% of graft-to-recipient weight ratio (GRWR) was only 54.5% in our experience at Kyoto University Hospital from 1994 to 2001 (8). These patients developed a typical small-for-size syndrome (SFSS), manifested by persistent hyperbilirunemia, coagulopathy, ascites, gastro-intestinal portal hypertensive bleeding and renal dysfunction after transplantation (9,10).

Although small-for-size graft (SFSG) is defined as less than 0.8% of GRWR (11), SFSS can occur in a range of GRWR 0.8–1% and in rare instances in grafts with greater than 1% of GRWR despite sporadic successes using small grafts less than 0.8% of GRWR. The factors that contribute to SFSS are multiple and not only include graft size, but also parenchymal steatosis, donor age, preoperative recipient condition, degree of portal hypertension and surgical complications. Furthermore, it has been reported that the increase in portal vein flow (PVF) and portal vein pressure (PVP) are important predictors of graft failure in SFSG (12,13).

The impact of PVF and PVP has led to the development of techniques of inflow modulation including splenic artery ligation (SAL) (12), splenectomy (14), mesocaval shunt with downstream ligation of the superior mesenteric vein (SMV) (15) or hemi-portocaval shunt (HPCS) (16). Animal studies have shown that partial diversion of portal flow to the systemic circulation can improve the function of SFSG with greater than 0.6% of GRWR (15,17). Recent clinical reports also demonstrated that the inflow modulation was effective in preventing SFSS in ALDLT using SFSG greater than 0.6% of GRWR (15,16). We have reported two successful ALDLTs using right lobe graft (RLG) with HPCS, which were 0.55% and 0.70% of GRWR (18).

Based on these early results, we developed an algorithm of graft selection in which left lobe donation is considered primarily if the GRWR is estimated to be greater than 0.6% in preoperative assessment with utilization of a HPCS based on PVP. In this study, we report our experience with successful ALDLT utilizing SFSG greater than 0.6% of GRWR under HPCS to reduce PVP.

Patients and Methods

  1. Top of page
  2. Abstract
  3. Introduction
  4. Patients and Methods
  5. Results
  6. Discussion
  7. Acknowledgments
  8. References

Recipients

Between December 2005 and August 2007, a total of 11 consecutive ALDLTs using SFSG greater than 0.6% of estimated GRWR were performed with/without HPCS based on intra-operative PVP. The protocol was approved by the Institutional Ethics Committee. Recipients were 5 men and 6 women, who ranged in age from 21 to 65 years (mean 48.2). Recipient body weight ranged from 53 to 99.3 kg (mean 70.2). The primary indications and preoperative patient conditions are shown in Table 1. Hepatocellular carcinoma was identified preoperatively in 4 patients. Child-Pugh score ranged from 7 to 13 (Child B in 4, Child C in 7). MELD score ranged from 6 to 25 (mean 14.2). ABO compatible or identical combination was seen in 9, and other 2 cases were ABO incompatible.

Table 1.  Recipient characteristics
CaseGenderAge (year)Primary indicationBW (kg)C-CCPSMELD
  1. Case: *= ABO incompatible case.

  2. Gender: M = male; F = female.

  3. Primary indication: HCV-LC = hepatitis C virus-related liver cirrhosis; HCC = hepatocellular carcinoma; FHF = fulminant hepatic failure; BW = body weight; C-C = child classification; CPS = Child-Pugh score; MELD = model for end-stage liver disease score.

 1F51HCV-LC, HCC85.4C1017
 2M50HBV-LC, HCC99.3B 711
 3F51HCV-LC, HCC53.0C1011
 4M38Wilson disease78.0C1222
 5*F64HCV-LC68.0C1015
 6M21Cryptogenic LC58.2B 8 9
 7F60Sub-acute FHF61.0C1216
 8*M55HCV-LC75.0C1325
 9F20Budd-Chiari syndrome57.7C1212
10F55HCV-LC, HCC63.5B 812
11M65Alcohol LC73.4B 7 6

Donors

There were 6 men and 5 women, who ranged in age from 22 to 59 years (mean 37.9) (Table 2). Body weight ranged from 52 to 70 kg (mean 60.9). Ten donors had no or slight steatosis on ultrasonography (US) and computed tomography (CT). However, one donor was found to have moderate steatosis (20%) on preoperative needle biopsy. Four RLGs and 7 LLGs were donated based on the following graft selection algorithm.

Table 2.  Donor characteristics and morbidities
CaseGenderAge (year)BW (kg)OthersMorbidity
  1. Gender: M = male; F = female.

  2. BW = body weight.

  3. Morbidity: *= right lobe donor.

 1M5069 Biliary leakage*
 2F5256 None*
 3F2255 None
 4F3752 None*
 5M3165 None
 6M5960Moderate steatosisNone
 7M3370 None
 8F4353 None*
 9M2770 None
10F3252 None
11M3168 None

Graft selection and criteria for HPCS

To determine anatomical variation and graft size, multi-detector CT (MDCT) imaging was performed for all potential donors. HepaVision2 (Mevis, Bremen, Germany) is a software tool specifically developed for image analysis and regional hepatic venous volumetry of the liver (19). On the basis of raw data obtained from multi-slice CT, various anatomic sites can be visualized and volumetry of portal and venous regional volume can be performed. Conventional volumetry, including whole liver volume, right lobe volume with or without middle hepatic vein (MHV), left lobe volume without caudate lobe and remnant liver volume were calculated using a previously reported method (20).

We used a LLG as our first choice when GRWR of LLG was greater than 0.6% in preoperative volumetry. We selected RLG transplantation when estimated GRWR of LLG was less than 0.6% and estimated GRWR of RLG was greater than 0.6% after confirming that the remnant liver volume was larger than 30% of the whole liver. Neither the recipient's preoperative condition, as determined by MELD score, nor graft quality was considered in selection of graft type. When actual graft volume (GV) was less than 1.0% of GRWR and PVP was more than 20 mmHg at the time of laparotomy, we determined the construction of HPCS with the branch of recipient portal vein (PV) (Figure 1).

image

Figure 1. Algorithm for the graft selection and selective HPCS. For adult recipients, a LLG is the first graft type for consideration. We use the LLG when the estimated GRWR of LLG is greater than 0.6% in preoperative volumetry. We select RLG transplantation when the estimated GRWR of LLG is less than 0.6% and estimated GRWR of RLG is greater than 0.6% after confirming that the remnant volume is larger than 30% of the whole liver. When actual GV is less than 1.0% of GRWR and PVP is more than 20 mmHg at the time of laparotomy, we determine the construction of HPCS with the branch of recipient PV.

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Measurement of portal vein pressure

A Swan-Ganz catheter was introduced for the evaluation of hemodynamics. With the catheter, central vein pressure (CVP) was tried to maintain less than 10 mmHg.

A 16-gauge antithrombotic catheter was inserted via the inferior mesenteric vein after recipient laparotomy. The tip of the catheter was positioned approximately 7–8 cm from site of insertion and then exited from the abdominal wall. PVP was continuously monitored using a transducer during the recipient operation. PVP and CVP measurements were done at the time of laparotomy, just before temporary portocaval shunt in the anhepatic phase, just after PV reperfusion, just after arterial reperfusion and before abdominal closure. Shunt function was confirmed by noting an increase in PVP after shunt clamping. PV flow direction and velocity were assessed with Doppler US after arterial reperfusion. We continued monitoring PVP and CVP for additional 5 days if the PVP was more than 20 mmHg at the end of operation in spite of a functioning shunt. The catheter, which was reinforced using rubber bands intra-operatively, was pulled out in the ICU.

Surgical techniques

The donor hepatectomy was performed as previously described (21). The grafts were weighed routinely after ex situ portal flushing on the back table with histidine-tryptophan-ketoglutarate solution. The recipient hepatectomy and implantation of the graft were performed using piggy-back technique (21).

A crucial point of hilar dissection in HPCS cases is to leave the pedicle of PV with the greatest possible length. The right PV and left PV were dissected distal to the bifurcation with dividing a few small branches at the level of the hilar plate. The right PV branch was usually short, but with large diameter, in contrast, the left PV branch was prepared with a longer pedicle, which attenuated gradually near the hilar plate. To elongate the PV pedicle, the trunk was dissected proximately from the surrounding tissue. To avoid splanchnic congestion during the anhepatic phase, a temporary end to side portocaval shunt between the inferior vena cava (IVC) and PV branch was constructed in all cases. In the case of HPCS, the distal end of the PV branch for the shunt was extended with a vein graft in advance and anastomosed to the IVC since a short shunt may seriously hamper adequate mobilization and anastomosis between the graft PV and the other branch of the recipient PV. When a long period of time was needed to obtain a vein graft, we prepared a temporary portocaval shunt first and inserted the vein graft just before graft placement. The inter-positional vein grafts were obtained from the auto PV branch, recipient paraumbilical vein or left renal vein.

In RLG, recipient right PV and graft PV were anastomosed (Figure 2) and in LLG, the anastomosis was conducted between recipient left portal branch and graft PV (Figure 3). When we anastomosed both PVs, the recipient PV was cut near the bifurcation leaving a diameter as large as possible. Reperfusion of the graft was performed after opening the shunt in order to avoid hyperperfusion. In cases without HPCS, the temporary shunt was divided and closed, and then PV reconstruction was done in an ordinary fashion.

image

Figure 2. RLG implantation with HPCS. A 16-gauge antithrombotic catheter is inserted to monitor PVP via the inferior mesenteric vein after recipient laparotomy. Left PV branch is sewn to IVC using a vein graft. Right PV is anastomosed to graft PV.

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image

Figure 3. LLG implantation with HPCS. When we anastomose both PVs, the recipient left PV is cut near the bifurcation leaving a diameter as large as possible. The inter-positional vein graft is obtained from the recipient left portal branch. Right PV branch is sewn to IVC using this vein graft.

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Evaluation of shunt patency and liver regeneration

PVF and velocity in the graft were evaluated by Doppler US. Doppler US was performed every day for 2 weeks after operation and once a week after patient discharge.

We investigated the effects of HPCS on liver regeneration. The regeneration rate was determined on the basis of the increase of GV by CT volumetry at 1, 3 and 6 months postoperatively. Shunt patency was confirmed by both MDCT and US at the same intervals postoperatively. Histological examination of a liver graft specimen taken on biopsy was performed if there was macroscopic evidence of steatosis and fibrosis.

Definition of SFSS

We used the definition of SFSS proposed by Pierre-Alain Clavien et al. (22) in which SFSS was divided into small-for-size dysfunction and small-for-size nonfunction. Small-for-size dysfunction is the dysfunction of a SFSG less than 0.8% of GRWR during the first postoperative week after the exclusion of other causes. Graft dysfunction is diagnosed by the presence of two of the following on three consecutive days: bilirubin≥100 μmol/L, INR≥2, encephalopathy grade III or IV.

Assessment of left lobe volume

We reviewed the left lobe volumetry using Mevis software on 90 donors who underwent right lobectomy in both Kyoto University Hospital and Kobe City General Hospital.

Results

  1. Top of page
  2. Abstract
  3. Introduction
  4. Patients and Methods
  5. Results
  6. Discussion
  7. Acknowledgments
  8. References

Donor morbidity

Donors have all returned to normal daily activity with good liver function, although one donor who underwent right hepatectomy had biliary leakage that was treated successfully with US guided percutaneous drainage. The others had no postoperative complication.

Patient survival and complications

The mean actual graft weight was 648.7g in RLGs (585–720) and 415.1g in LLGs (340–505). The GRWR of the implanted livers ranged from 0.58% to 0.79%. The mean GRWR in RLG was 0.77% (0.73–0.79) and in LLG was 0.65% (0.58–0.77) (Table 3). Donor biopsy at the time of hepatectomy showed 0∼5% macro-vesicular steatosis in 8 cases, 5∼10% in 2 cases and 10∼15% in 1 case.

Table 3.  Graft characteristics and hemi-portocaval shunt procedure
CaseGraftActual GW* (g)GRWR** (%)HPCS***Vein graft
  1. Graft: RLG+MHV = right lobe graft with middle hepatic vein; RLG = right lobe graft without middle hepatic vein; LLG = left lobe graft.

  2. *GW = graft weight; **GRWR = graft-to-recipient weight ratio; ***HPCS = hemi-portocaval shunt.

  3. Vein graft: Auto PV = auto portal vein branch; LRV = left renal vein; UV = paraumbilical vein.

 1RLG6750.79(+)Auto PV
 2RLG+MHV7200.73(+)Auto PV
 4RLG6150.78(+)Auto PV
 8RLG5850.78(+)Auto PV
 3LLG3950.73(+)LRV
 5LLG4000.58(+)UV
 6LLG5050.77(+)Auto PV
 7LLG4600.76(−)
 9LLG3400.59(+)UV
10LLG3800.59(+)Auto PV
11LLG4260.58(+)Auto PV

All ten patients having HPCS survived and are going well with normal liver function with a median follow-up of 296 days (range 40–621 days). One patient (case 7) without HPCS died of chronic vascular rejection on postoperative day (POD) 61. The patient was discharged uneventfully on POD 21 (T-Bil 1.4 mg/dL, INR 1.09).

The rates of acute rejection, infectious, vascular and biliary complications were 30%, 20%, 0%, 30%, respectively. Changes in serum bilirubin are shown in Figure 4. Two (3: GRWR 0.73, 11: GRWR 0.58) of 11 patients developed pneumonia, which led to an increase of serum bilirubin. Neither of the two presented with encephalopathy nor INR more than 2 during the first postoperative week. After treatment with antibiotics, the serum bilirubin decreased. Coagulopathy, prolonged cholestasis and encephalopathy were not seen in the other nine patients. And also intractable ascites was not encountered in all cases.

image

Figure 4. Changes in serum bilirubin level after LT. Solid circle means mean value of serum bilirubin of other nine cases.

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PVP study

Ten patients required HPCS using a vein graft. In one patient with subacute fulminant hepatic failure, a temporary portocaval shunt was used to avoid mesenteric congestion during the anhepatic phase but then dismantled before grafting due to low PVP at the time of laparotomy. The vein graft was auto PV branch in 7 cases, paraumbilical vein in 2 and recipient left renal vein in one (Table 3).

The mean PVP was 28.9 mmHg (22–36) and the mean CVP was 8.1 mmHg (7–10) at the time of laparotomy, increased to 38.4 mmHg (30–48) just before temporary portocaval shunt in the anhepatic phase, decreased to 18.8 mmHg (12–24) just after PV reperfusion and increased slightly to 19.6 mmHg (13–25) just after hepatic artery reperfusion in HPCS cases. In all cases except one, PVP were regulated successfully under 20 mmHg before abdominal closure (Table 4). One patient had PVP of 23 mmHg at the end of operation in spite of shunt function associated with high CVP of 17 mmHg, PVP decreased to 17 mmHg (CVP 7 mmHg) on POD 1 and 17 mmHg (CVP 9 mmHg) on POD 2. There were no cases that needed surgical intervention for shunt occlusion because of shunt steal phenomenon or insufficiency of graft PVF, which was confirmed with Doppler US.

Table 4.  Changes in portal vein pressure and central vein pressure (mmHg) in hemi-portocaval shunt cases
CaseGRWR*(%)A (CVP**)BCDEF (CVP)
  1. *GRWR = actual graft-to-recipient weight ratio.

  2. **CVP = central vein pressure.

  3. A = At the time of laparotomy; B = just before temporary portocaval shunt in the anhepatic phase; C = just after portal vein reperfusion; D = portal vein pressure after test clamping of hemi-portocaval shunt; E = just after arterial reperfusion; F = before abdominal closure.

 10.7928 (9)46244725 23 (17)
 20.7327 (7)3720252019 (9)
 30.7336 (7)3712231312 (9)
 40.7829 (9)3515181616 (9)
 50.5833 (9)43202620 20 (10)
 60.7728 (7)3420272120 (7)
 80.7828 (7)3220222019 (8)
 90.5930 (9)33173218 16 (10)
100.59 22 (10)30202720 20 (10)
110.5828 (7)48202923 20 (12)

Shunt patency and graft regeneration

Determination of GV by CT volumetry was performed postoperatively at 1, 3 and 6 months after surgery. Rapid regeneration of GV was observed and reached in a mean 84.3% of standard liver volume (SLV) in RLGs and mean 95.4% in LLGs at 3 months after liver transplantation (LT). Both RLGs and LLGs attained approximately 90% of SLV by 6 months after LT. All surviving cases had evaluation for HPCS patency by Doppler US and MDCT up to one year. Actuarial rate of primary patency at one month, 3 months, 6 months and 1 year were 80%, 55%, 26% and 20%, respectively.

Discussion

  1. Top of page
  2. Abstract
  3. Introduction
  4. Patients and Methods
  5. Results
  6. Discussion
  7. Acknowledgments
  8. References

Donor organ shortage is a major issue in LT. LDLT and split liver transplantation (SLT) are surgical procedures that can address organ shortage. LDLT has become a viable alternative, particularly in countries where brain death law is missing or insufficient. However, LDLT has not been performed as frequently as anticipated because of donor death and morbidity. So far, 19 cases of documented donor death have been reported worldwide (23). In particular, potential donor risk has increased since the introduction of RLG transplantation. In Japan, multi-center studies have shown that the incidence of postoperative complications was higher for right lobe donation than for left lobe donation, and that the incidence of biliary tract complications was also higher for right lobe donation (5). Based on this morbidity, LLG for adult recipient is being reexamined. The minimum amount of liver graft necessary for successful transplantation for adult recipients is proposed to be greater than 0.8% of GRWR (11). Graft size is a key factor for overcoming SFSS. SFSS leads to inhibition of graft regeneration resulting in graft failure within 2 or 3 months in approximately 50% of recipients (24). Therefore, right lobe donation, although increasing the risk for the living donor, has been the preferred graft throughout the world.

The mechanism of SFSS is not yet fully understood. However, graft over-perfusion and portal hypertension play an important role. Parenchymal injury due to reperfusion results in prolonged hyperbilirunemia and impaired regenerative capacity ultimately resulting in infection (11). We have shown that graft survival deteriorated significantly when PVP was more than 20 mmHg in the early postoperative period. In addition, PVP was significantly elevated when GRWR was less than 0.8%. Histological examination showed the parenchymal injury caused by high PVP (13).

Several techniques for inflow modulation for a small graft have been proposed. These include SAL, splenectomy or spleno-renal shunt reconstruction (25). Preservation of spontaneous portosystemic shunt has been reported (26). However, the latter method is difficult for quantitative evaluation and SAL has not been uniformly successful in modulating PVP because of early rebound of PVP as shown in our previous study (13). Troisi, et al. were not able to significantly decrease PVF when it was over 500 mL/min/100 g of liver by means of SAL and they recommended banding the PV in one case and performed left HPCS during the anhepatic phase in one (12). Although splenectomy is able to lower PVP, it cannot be recommended as a routine procedure. In addition, portal vein thrombosis is one of the lethal complications of splenectomy.

Another method of inflow modulation in the treatment of SFSG is the creation of an artificial portosystemic shunt as reported in experimental LT with SFSG in dogs (27) and in pigs (15,17). Boillot et al. diverted the superior mesenteric venous flow by mesocaval shunt with downstream ligation of the SMV (15), however, long-term follow-up of this procedure has not been reported. Troisi et al. reported that the reduction of PVF by means of HPCS improves overall patient survival and risk of complication by avoiding the occurrence of SFSS in grafts less than 0.8% of GRWR in adults. HPCS was performed by direct anastomosis of the hemi-portal branch to the IVC. And the graft PVF was adjusted to around two times of the PVF, which was recorded in the donor side with banding of HPCS to decrease excessive shunting and prevent a steal phenomenon (16).

We measured the PVP and PVF simultaneously using an intracatheteric fine wire with a flow sensor tip. The sequential measurements suggested that PVP and PVF did not necessarily parallel each other and highly depended on the graft and extra-hepatic factors including hemodynamics. The rapid increases in PVF gradually decreased and were accompanied by gradual increases in PVP after reperfusion in most recipients (13). The PVP measurement is a simple method and can continuously monitor the changes in PVP during recipient operation.

HPCS can avoid the initial graft injury due to high PVP, and provide adequate PVF to the graft. Kelly et al. reported that as early as 5 min after reperfusion sinusoidal congestion and hemorrhage are evident in 20% partial liver grafts in pigs. The severity of these changes is inversely related to graft size, being less pronounced in 30% and 60% and absent in full liver grafts (28).

Technical refinement is crucial to the performance of HPCS in order to avoid the kinking of the graft PV anastomosis, which would result in turbulence and thrombosis. To obtain sufficient length, we routinely used a vein graft between the IVC and PV branch in left lobe grafting because of the short right PV branch. There are limitations to vein graft harvesting in LDLT, but this issue was resolved by using recipient PV procured ex situ or in situ, renal vein, or patent paraumbilical vein. By anastomosing the vein graft to the portal branch to form a shunt of enough length, the shunt position remained favorable without kinking.

Can we expand the use of grafts with less than 0.8% of GRWR for patient with severe end-stage liver disease? Some institutions select the left lobe based on factors such as pretransplant patient condition according to the MELD score (6), original disease (7,29) and left lobe volume if it is greater than 40% of SLV or greater than 0.8% of GRWR, but the number of LLG transplantation would be limited according to these selection criteria. We reviewed the left lobe volumetry using Mevis software on 90 donors who underwent right lobectomy in both Kyoto University Hospital and Kobe City General Hospital and if left lobe grafting had been selected, GRWR would have been ≥1% in 10% of the patients, 0.8–1.0% in 10% of the patients, 0.6–0.8% in 55% and <0.6% in 25%. Therefore, if the same results we have achieved in the present series by using grafts ≥0.6% of GRWR, then 75% of the donors could have been candidates for left lobe donation. In this study, we used grafts less than 0.8% of GRWR (mean GRWR was 0.77% in RLG and 0.65 in LLG) with selective HPCS and achieved 0% occurrence of SFSS and 100% patient and graft survival (mean follow-up: 296 days). In our early 39 left lobe ALDLT series (1994–2001), the patient survival was 82.1% in recipients with ≥0.8% of GRWR (n = 28), whereas 54.5% in recipients with <0.8% of GRWR (n = 11) (8). In the 11 recipients, age ranged from 26 to 61 years (mean 37.7), Child A, B and C were in 1, 3 and 7, respectively. GRWR ranged from 0.59% to 0.79% (mean 0.70), MELD score ranged from 8 to 35 (mean 23.0). PVP had not been measured in this series. This strongly suggests that favorable results can be obtained using a LLG with HPCS in many recipients. Despite greater safety for the donor, there is anatomical superiority in LLG compared to RLG (30). The LLG contains sufficient outflow tributaries, a single branch of the PV, and especially, a single bile duct in most cases. Thus, a LLG has several technical advantages over a RLG. The only difficulty is the small size of the left hepatic artery.

In our study, rapid volumetric regeneration of GV was observed and reached a mean of 84.3% of SLV for RLGs and 95.4% of SLV for LLGs at 3 months after LT. RLG without MHV sometimes results in congestion of the anterior segment and leads to insufficient regeneration (31,32). In contrast, the Mevis study showed equal regeneration between V2, V3 and V4 segments in LLG indicating unimpaired regenerative capacity.

This study suggested a small graft of greater than 0.6% of GRWR could be used in adult recipients and potentially LLG could be used in 75% of adult recipients in LDLT. The utility of SFSG less than 0.8% of GRWR with HPCS procedure for severely sick patients with high MELD score or high PVP is not determined yet by this study. However, selective HPCS could achieve a better outcome of adult LDLT for sicker patients and SLT. SLT has been reported in small numbers annually in the world despite an increasing organ shortage especially in adult recipients. Eurotransplant showed that adult recipients received 3243 liver transplantations, 3070 (94.7%) whole and 173 (5.3%) split-liver grafts between January 1, 2002, and December 31, 2004 (33). Azoulay et al. reported that the reason for the rarity of this procedure is the very poor results achieved for adult recipients of left split-liver grafts (34). Higher threshold of liver volume has been considered in SLT compared to LDLT because splitted deceased donor grafts are subjected to a longer period of cold ischemia and to a more relevant ischemia-perfusion injury due to the split procedure itself. If split liver grafts could be transplanted into two adult patients, the number of SLTs would increase and the number of patients on the waiting list would be reduced.

In conclusion, selective HPCS based on PVP is an effective procedure and results in excellent patient and graft survival with avoidance of SFSS in grafts greater than 0.6% of GRWR.

Acknowledgments

  1. Top of page
  2. Abstract
  3. Introduction
  4. Patients and Methods
  5. Results
  6. Discussion
  7. Acknowledgments
  8. References

The authors thank Dr Hisashi Shinohara for illustrating figures. Presented at the 13th congress of the European Society for Organ Transplantation, September 29–October 3, 2007, Prague, Czech Republic.

References

  1. Top of page
  2. Abstract
  3. Introduction
  4. Patients and Methods
  5. Results
  6. Discussion
  7. Acknowledgments
  8. References
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