Correlation of portal venous velocity and portal venous flow with short-term graft regeneration in recipients of living donor liver transplants

BACKGROUND: To evaluate the correlation of postoperative portal venous velocity (PVV) and portal venous flow (PVF) with the degree of short-term graft regeneration in recipients of living donor liver transplantation (LDLT). MATERIALS AND METHODS: Between August 2005 and April 2006, we performed 44 adult-to-adult LDLTs with right-lobe grafts, of whom 31 recipients were included in this study. Doppler ultrasonography was used to measure PVV (cm/s) and PVF (mL/min) on postoperative days (POD) 1, 3, and 5 or 6. Portal venous velocity index (PVI) was defined as the ratio of PVV to graft weight (GW), and portal flow volume index (PFI) as the ratio of PVF to GW. Graft regeneration rate (GRR), defined as the ratio of the volume of regenerated graft to GW, was estimated by dividing computed tomography volumetry at POD 7 by GW measured after retrieval of the graft. We analyzed the relationship between GRR and PVV, PVF, PVI, and PFI. RESULTS: GW ranged between 528 g and 1040 g (mean = 735 g) and GRR ranged between 118% and 278% (mean = 172%). Although neither PVV nor PVF correlated with GRR, PVI and PFI at POD 1 (P = .009) and PFI at POD 5 or 6 (P = .012) significantly correlated with GRR at POD 7. CONCLUSION: PVI and PFI at POD 1 are useful indicators to predict short-term graft regeneration in recipients of LDLT.     

Segmental regeneration in right-lobe liver grafts in adult living donor liver transplant

Chen H‐L, Tsang LL‐C, Concejero AM, Huang T‐L, Chen T‐Y, Ou H‐Y, Yu C‐Y, Chen C‐L, Cheng Y‐F. Segmental regeneration in right‐lobe liver grafts in adult living donor liver transplant. Abstract:  Our aim is to evaluate the relationship and impact of right‐lobe (RL) liver grafts procured with or without the middle hepatic vein (MHV) trunk and MHV tributary reconstruction on segmental regeneration of these grafts in adult living donor liver transplantation (ALDLT). Patients underwent primary ALDLT using a RL liver graft were divided into three groups according to graft type: with MHV tributary reconstruction (group I), without MHV tributary reconstruction (group II), and with inclusion of the MHV trunk (group III). The overall graft volume and the volumes of the anterior and posterior segments of the grafts six months post‐transplant, evaluated using computed tomography, were calculated as the regeneration indices. Optimal regeneration of the RL liver graft was achieved in the three groups of patients. There was no significant difference in the regeneration indices between groups I (149.4%) and III (143.6%). However, in group II (112.4%) without MHV or tributary reconstruction, the anterior regenerative index was lower than the other two groups and exhibited transient prolonged hyperbilirubinemia. Segmental graft regeneration is maximized by adequate venous drainage. Inclusion of the MHV trunk or MHV tributary reconstruction influences segmental liver regeneration and preclude transient hyperbilirubinemia in the early post‐liver transplant phase.     

The interrelationship between portal and arterial blood flow after adult to adult living donor liver transplantation

BACKGROUND: When adults are transplanted with segmental grafts, disparity between the size of the graft and the native organ is almost universal. These grafts presumably still receive all of the native portal inflow despite a reduced vascular bed and dramatically elevated blood flow may result. The hemodynamic changes after segmental transplantation in adults have not yet been studied and their clinical significance is unknown. METHODS: Portal venous and hepatic arterial blood flow were measured intraoperatively in right lobe liver donors and recipients with electromagnetic flow probes. Postoperative evolution was monitored in recipients with ultrasonography. RESULTS: Portal flow to the right lobe ranged from 601 to 1,102 ml/min before resection and from 1,257 to 2,362 ml/min after transplantation. There was a statistically significant linear correlation between the change in portal flow and graft to recipient body weight ratio. Arterial blood flow ranged from 213 to 460 ml/min before resection and from 60 to 300 ml/min after transplantation. Preoperative portal peak systolic velocity was uniformly around 10 cm/sec. Values on postoperative day 1 were increased to 30 cm/sec in recipients of cadaveric organs, to 50 cm/sec in recipients of organs with graft to recipient body weight ratios of more than 1.2%, and to 115 cm/sec in recipients of organs with ratios less than 0.9%. A decreasing tendency was universally observed. Arterial systolic velocity was inversely related to portal systolic velocity. Neither graft dysfunction nor vascular complications occurred. CONCLUSIONS: The hemodynamic pattern after right lobe transplantation is predictable and intraoperative measurements and ultrasonography are useful for monitoring. The size of the graft influences the magnitude of the hemodynamic changes.     

Clinical relevance of adapting portal vein flow in living donor liver transplantation in adult patients

Size mismatching is a major concern in adult living donor liver transplantation (ALDLT). Graft hyperperfusion in these grafts is considered the main factor leading to graft dysfunction and poor survival. We describe the clinical significance of graft inflow modification (GIM) by splenic artery ligation in a series of 24 consecutive ALDLT. Between September 1999 and December 2001, 24 patients underwent ALDLT at our institution. Patients were divided into two groups: G1, n = 11 without GIM, and G2, n = 13 with GIM. Both groups were equivalent in terms of preoperative clinical state, graft characteristics, and surgical technique. Graft hyperperfusion was noticed overall, especially in small grafts (graft-to-recipient body weight ratio <0.8), with mean recipient portal vein (rPVF) values at least three times greater than those recorded in the donors. GIM permitted in G2 a significant decrease in rPVF. Small-for-size syndrome (SFSS) occurred in three (27%) patients in G1 with small grafts showing graft hyperperfusion and necessitating a retransplantation. SFSS did not occur in G2. One-year overall survival was 62% and 93% respectively for G1 and G2. It is concluded that when small-for-size grafts are accompanied by graft hyperperfusion, the rPVF should be lowered to avoid the SFSS and to improve the outcome. (Liver Transpl 2003;9:S36-S41.)     

Functional portal flow competition after auxiliary partial orthotopic living donor liver transplantation in noncirrhotic metabolic liver disease

Auxilliary partial orthotopic liver transplantation (APOLT) was introduced initially as a tentative or permanent support for patients with potentially reversible fulminant hepatic failure and has extended its indication to congenital metabolic disorder of the liver that has otherwise normal functional integrity. Postoperative management of APOLT is complicated because of functional portal flow competition between the native and graft liver. The native portal vein diversion to the graft is sometimes indicated to prevent functional competition; however, it is still an open question whether this technique can be theoretically indicated for APOLT patients. The authors report a on patient with ornithine transcarbamylase deficiency who received APOLT from a living donor without native portal vein diversion. Because of functional portal vein competition between the native and graft liver, the patient had to have portal vein diversion, portal vein embolization, and finally native hepatectomy to induce the graft regeneration after APOLT. After the experience of the current case, primary portal vein diversion for APOLT with noncirrhotic metabolic liver disease patients to prevent functional portal flow competition is recommended.     

Reversible hepatofugal portal flow after liver transplantation using a small-for-size graft from a living donor

We describe a case of reversible hepatofugal portal flow 1 week after transplantation of a small-for-size liver graft from a living donor. A transient increase in intrahepatic portal vascular resistance was the suspected cause. The portal venous flow normalized after residual collateral channels had been interrupted surgically. The patient was discharged on the 90^th postoperative day. Liver transplant clinicians should be aware that hepatofugal flow can occur with small-for-size liver grafts, despite sufficient portal venous flow immediately after transplantation. Received: 8 March 2000 Revised: 26 September 2000 Accepted: 5 May 2001     

Simultaneous hepatic artery and portal vein thrombosis after living donor liver transplantation

Simultaneous hepatic artery and portal vein thrombosis rarely occurs after liver transplantation. The etiology is unknown. Of 213 patients (72 children and 141 adults) that underwent living donor liver transplantation (LDLT) from January 1996 to March 2003, 4 (2%) developed simultaneous thrombosis at 3 hours to 7 days (median, 4 days) after the operation. Emergent thrombectomy was performed in three patients; the remaining patient was registered in the Japan organ transplant network. All of the patients died due to hepatic failure (range, 18 hours to 6 days after the diagnosis; median, 2 days). Portal vein, hepatic artery, and hepatic vein velocity in the liver graft were measured every 12 hours by Doppler ultrasonography for 2 weeks after liver transplantation. These parameters were stable until just before the simultaneous thrombosis. These findings indicate that protocol Doppler ultrasonography can diagnose, but not predict, this fatal complication.     

Intraoperative ultrasound guided portal venous thrombectomy in living donor liver transplantation recipient surgery.

Portal vein reconstruction in liver transplantation from live donor grafts has major challenging factors in cases with portal venous thrombosis (PVT). To overcome this critical surgical challenge, we devised a novel technique, intraoperative ultrasonography (IOUS)-guided thrombectomy of the portal vein. IOUS-guided thrombectomy was applied to the 10 patients whose PVT extended to the splenomesenteric junction. In these patients, closed thin scissors were inserted from the stump of the recipient portal vein under ultrasound guidance and the thrombus was dissected from the venous wall. The application of IOUS-guided thrombectomy in patients with moderate to severe PVT led to a 3-year patency rate of 83%, comparable to that of simple thrombectomy applied to partial or minimal (grade I-II) PVT (83%). IOUS-guided thrombectomy is helpful to adequately remove severe thrombi from the deep lumen of the portal vein, provided the procedure was carried out by an experienced surgeon with adequate preparation for unexpected venous injuries.     

Intra-operative management of low portal vein flow in pediatric living donor liver transplantation

For pediatric living donor liver transplantation, portal vein complications cause significant morbidity and graft failure. Routine intra-operative Doppler ultrasound is performed after graft reperfusion to evaluate the flow of portal vein. This retrospective study reviewed 65 children who had undergone living donor liver transplantation. Seven patients were detected with suboptimal portal vein flow velocity following vascular reconstruction and abdominal closure. They underwent immediate on-table interventions to improve the portal vein flow. Both surgical and endovascular modalities were employed, namely, graft re-positioning, collateral shunt ligation, thrombectomy, revision of anastomosis, inferior mesenteric vein cannulation, and endovascular stenting. The ultrasonographic follow-up assessment for all seven patients demonstrated patent portal vein and satisfactory flow. We reviewed our experience on the different modalities and proposed an approach for our future intra-operative management to improve portal vein flow at the time of liver transplantation.     

Changes in portal venous pressure in the early phase after living donor liver transplantation: pathogenesis and clinical implications

BACKGROUND: Although living-donor liver transplantation (LDLT) has been accepted for adult populations, the occurrence and pathogenesis of small-for-size syndrome remain highly controversial. METHODS: Portal venous pressure (PVP) was measured in 79 cases of LDLT from anhepatic phase to day 14. PVP was monitored through a catheter inserted via the inferior mesenteric vein. In a separate series of seven cases of adult LDLT, the splenic artery was ligated following arterial reperfusion. RESULTS: For days 2 to 4 and 9 to 11, recipients of small-for-size graft (<0.8% of body weight) displayed significantly higher PVP than recipients of larger grafts. The 13 patients with elevated mean PVP (>or=20 mm Hg) early in the first week (days 0-4) demonstrated significantly worse survival (84.5% vs. 38.5% at 6 months; P < 0.01), but this was not applicable to elevated mean PVP late in the first week (days 5-7). Elevated PVP early in the first week was also associated with higher incidence of bacteremia, cholestasis, prolonged prothrombin time, and ascites. Splenic artery ligation (SAL) immediately reduced PVP from 10 to 20 mm Hg (median, 16 mm Hg) to 9 to 13 mm Hg (median, 11 mm Hg; P = 0.02). Posttransplant PVP was significantly lower in SAL patients than in non-SAL patients from days 2 to 7 despite small graft size. Early PVP in SAL patients was consistently below 20 mm Hg, and survival was significantly better than in non-SAL patients with high early PVP (P < 0.01). CONCLUSION: Elevated PVP in the early phase is strongly associated with poor patient survival attributable, at least in part, to small-for-size graft. Further elucidation of the pathogenesis behind this phenomenon and efforts to modify PVP will be key to improving results.     

Endoscopic management of biliary complications after adult right-lobe living donor liver transplantation without initial biliary decompression

Objectives

We sought to examine biliary complications in adult right-lobe living donor liver transplantation (LDLT) with duct-to-duct anastomosis (RL-LDLT-DD), evaluating the efficacy of endoscopic retrograde cholangiography (ERC) in the diagnosis and management of biliary complications following LDLT.

Methods

Ninety adult RL-LDLT-DD were performed from June 2004 to August 2007, including 21 (23.3%) cases of biliary complications.

Results

The endoscopic retrograde cholangiopancreatiography (ERCP) findings were stricture only (n = 8), stricture plus leakage (n = 9), and leakage only (n = 4). In the overall 13 cases of leakage, nine patients recovered after treatment by stent or endoscopic nasobiliary drainage. The time to resolution was 3.0 ± 1.3 months with 2.2 ± 1.3 endoscopic examinations. All bile duct complications were treated by ERC first. Among 17 cases with stricture, seven cases were successfully treated by endoscopy and three cases by percutaneous transhepatic cholangiography plus stent (PTCS). In the other seven cases, the treatment was still ongoing in five cases and two subjects died during treatment. The mean time to stricture resolution 7.2 ± 3.3 months with 3.9 ± 1.4 endoscopic examinations. The results of 21 cases were 5/21 mortalities (23.8%), successful ERC treatment in 9/21; (42.9%), successful PTCS treatment in 3/21 (14.3%), and ongoing ERC treatment in 5/21, (23.8%), including one case with successful ERC treatment who died of lung infection postoperatively. During follow-up (13.1 ± 9.9 months), there was no recurrence in the stricture or leak.

Conclusions

When compared with the literature, RL-LDLT-DD without biliary drainage does not increase the incidence of biliary complications. From our study, ERC and PTC play a complementary roles in the treatment of bile duct complications.     

Transumbilical portal venous catheterization: a useful adjunct in left lobe living donor liver transplantation

To improve the processes used for perfusion of the explanted graft and measuring the portal venous pressure (PVP) in adult living donor transplantation (LDLT), we performed transumbilical portal venous catheterization (TPVC) to reopen the umbilical vein and insert the catheter for seven adult patients undergoing left lobe LDLT. There were no major complications as a result of this procedure. This procedure prior to implanting the graft was derived from our experience and is a classic diagnostic technique used during liver surgery. It is a simple and effective procedure for perfusion and washout of the graft and for the safe monitoring of the intraoperative PVP. We hope that this technique for left lobe LDLT will be helpful to others using postoperative PVP monitoring, administration of therapeutic drugs through the portal vein, and temporal portal decompression by preparation of extracorporeal shunting in patients with a small‐for‐size graft.     

Diagnosis and treatment of pediatric patients with late-onset portal vein stenosis after living donor liver transplantation

Portal vein stenosis (PVS) after living donor liver transplantation (LDLT) is a serious complication that can lead to graft failure. Few studies of the diagnosis and treatment of late-onset (≥3 months after liver transplantation) PVS have been reported. One hundred thirty-three pediatric (median age 7.6 years, range 1.3–26.8 years) LDLT recipients were studied. The patients were followed by Doppler ultrasound (every 3 months) and multidetector helical computed tomography (once a year). Twelve patients were diagnosed with late-onset PVS 0.5–6.9 years after LDLT. All cases were successfully treated with balloon dilatation. Five cases required multiple treatments. Early diagnosis of late-onset PVS and interventional radiology therapy treatment may prevent graft loss.     

成人间活体右半肝移植术中变异门静脉右支切取与重建技术

目的 探讨成人间活体右半肝移植术中变异门静脉支(APVB)切取与重建的技巧.方法 2002年1月至2007年4月,共实施70例成人间活体右半肝移植.术前肝脏血管三维CT成像显示供肝动脉及静脉走向,70例右半供肝中有9例门静脉分支变异,其中7例为Ⅱ型变异,2例为Ⅲ型变异.除1例供者行狭窄桥状连接单口切取APVB外,其余8例均采用供者优先的原则即距门静脉主干2～3mm处双口切断APVB.Ⅱ型变异中有2例双口切取其右前、右后支成形为一个开口后与受者门静脉主干吻合,4例右前、右后支分别与受者门静脉左、右支吻合,1例行右前、右后支间狭窄桥状组织连接单口切取后与受者门静脉主干单口吻合.Ⅲ型变异中有1例双口切取其右前、右后支分别与受者门静脉支双口吻合,1例双口切取后行新型的U形血管移植物间置与受者门静脉主干单口吻合.结果 9例受者均无门静脉狭窄或血栓、肝动脉狭窄或血栓以及肝静脉流出道狭窄等血管并发症发生.1例供者术后3 d并发门静脉血栓,手术取栓及门静脉壁修补成形后痊愈.新型的U形血管移植物间置重建术后通畅,无并发症发生.结论 成人间活体右半肝移植术中采用供者优先的原则双口切取APVB、双口吻合重建以及新型的U形血管间置等门静脉重建技术是安全可行的,未增加手术难度,且临床效果良好.     

Clinical analysis of living donor liver transplantation in patients with portal vein thrombosis

Kim S‐J, Kim D‐G, Park J‐H, Moon I‐S, Lee M‐D, Kim J‐I, Yoon Y‐C, Yoo Y‐K. Clinical analysis of living donor liver transplantation in patients with portal vein thrombosis.
Clin Transplant 2011: 25: 111–118. © 2010 John Wiley & Sons A/S. Abstract: The aim of this study was to improve outcomes in living donor liver transplantation (LDLT) patients with portal vein thrombosis (PVT). Of 246 adult patients who underwent LDLT with a right lobe graft between January 2000 and May 2007, PVT was diagnosed in 50 patients (20.3%), who were further subdivided into partial (n = 39, 78%) and complete (n = 11, 22%) types. Patients with PVT, especially complete PVT, showed high incidences of variceal bleeding (p = 0.021), operative RBC transfusion (p < 0.046) and a post‐transplantation complications related to bleeding (p = 0.058). We also classified PVT according to its location and the presence of collaterals: type I (n = 41, 82%): PVT localized above the confluence of the splenic and superior mesenteric veins (SMV); type II (n = 7, 14%): PVT extending below the confluence with a patent distal SMV; type III (n = 2, 4%): complete portal vein and SMV thrombosis except for a coronary vein. LDLT could be safely undertaken in patients with PVT without increased mortality. In our type II and III PVT, when thrombectomy fails, jump grafting using a cryopreserved vessel may serve as a reliable alternative method to restore portal flow.     

Living donor liver transplantation and management of portal venous pressure

Small-for-size syndrome occurs in the presence of a reduced mass of liver that is insufficient to maintain normal liver function. It has been speculated that this dysfunction is principally associated with graft exposure to excessive portal perfusion. The aim of these cases was to evaluate the efficacy of octreotide, a splanchnic vasoconstrictor, and esmolol, a selective beta-blocker, to modify the portal perfusion in the postoperative phase after left living related liver transplantation (LRLT). Four patients who underwent left LRLT with graft-to-recipient weight ratios of 0.60 +/- 0.24 were studied with a catheter placed in a jejunal vein. We observed high basal values of hepatic venous pressure gradient (HVPG) and portal vein flow (PVF). Octreotide infusion decreased HVPG, an effect that was more pronounced when it was combined with esmolol. The administration of both drugs was also associated with an improvement in portal vein oxygen saturation. Despite variation in PVF, the plasma disappearance rate of indocyanin green did not change during the infusion of the two drugs. In conclusion, octreotide and esmolol infusion allowed a manipulation of portal vein pressure that should be measured in left LRLT using a small-for-size graft.     

Surgical procedures for management of right portal venous branching in right lobe living donor liver transplantation

OBJECTIVE: This study sought to describe the surgical management of right portal venous (PV) branches encountered among 104 cases of right lobe living donor liver transplantation (LDLT). METHODS: From January 2002 to September 2007, we performed 104 cases of right-lobe LDLT including 11-donors who had anomalous right portal venous branches (APVB). One recipient had PV sponginess hemangioma. The donor right PV branches were type I in 93 cases, type II (trifurcation) in nine cases, and type III in two cases. Except one narrow bridge of tissue excision, the PV branches were transected on the principal of donor priority: PV branches were excised approximately 2 to 3 mm from the confluence while leaving the donor's main portal vein and confluence intact. In type II APVB, donor PV branches were obtained with two separate openings in six cases; with two separate openings joined as a common orifice at the back table in two cases, with one common opening with a narrow bridge of tissue in one case. In type III APVB, the donor right anterior and posterior PV branches were obtained with separate openings. The donor right PV branches with one common opening in 92 cases of type I PV branches and a joined common orifice in three cases of type II APVB were anastomosed to the recipient's main portal vein or to right branching. As the unavailable recipient PV for sponginess hemangioma, one case of type I right PV branches was end-to-end anastomosed to one of the variceal lateral veins of about 1 cm diameter in a pediatric patient. The PV were reconstructed as double anastomoses in six type II APVB and in one type III APVB obtained with two separate PV openings. In the another type III APVB reconstruction, we successfully utilized a novel U-shaped vein graft interposition. RESULTS: The type II APVB donor receiving a narrow bridge of portal vein tissue excision developed portal vein thrombosis on the third postoperative day and underwent reexploration for thrombectomy. There were no vascular complications, such as portal vein thrombosis or stricture among other donors or all recipients. The velocity of blood flow in the U-graft was normal. The anastomosis between the type I donor right portal vein and recipient variceal lateral vein was unobstructed. CONCLUSION: Right PV branches should be excised on the principal of donor priority while leaving the donor's main portal vein and confluence intact. Single anastomoses was the fundamental procedure of right branch reconstruction. Double anastomoses could be used as the main management for type II and type III APVB reconstruction. U-graft interposition may be a potential procedure for type III APVB reconstruction. Single anastomoses between the donor right portal vein and the recipient variceal lateral vein may be performed when recipient portal vein is unavailable. These innovations for excision and reconstruction of right PV branches were feasible, safe, and had good outcomes.