Orthotopic liver transplantation with preservation of portocaval flow compared with venovenous bypass

Preliminary experience with continuous right ventricular pressure and transesophageal echocardiography monitoring in orthotopic liver transplantation

Background

Despite increasing attention in the cardiac anesthesiology literature, continuous measurement of right ventricular pressure using a pulmonary artery catheter has not been described in orthotopic liver transplantation, despite similarities in the anesthetic approach to the two populations. We describe our preliminary experience with this technique in orthotopic liver transplantation, and by combining various derived measures with trans-esophageal echocardiography, make some early observations regarding the response of these measures of right ventricular function during the procedure.

Methods

In this case series, ten patients (five men and five women) undergoing orthotopic liver transplantation in our institution had their surgeries performed while monitored with a pulmonary artery catheter with continuous right ventricular port transduction and trans-esophageal echocardiography. We recorded various right ventricular waveform (early-to-end diastolic pressure difference, right ventricular outflow tract gradient, right ventricular dP/dT and right ventricular end-diastolic pressure) and echocardiographic (right ventricular fractional area change, tricuspid annular plane systolic excursion, right ventricular lateral wall strain) and described their change relative to baseline at timepoints five minutes before and after portal vein reperfusion, immediately after hepatic artery reperfusion and on abdominal closure.

Results

Except for tricuspid annular plane systolic excursion at five minutes prior to reperfusion (mean −0.8 cm; 95% CI−1.4, –0.3; p = 0.007), no echocardiographic metric was statistically significantly different at any timepoint relative to baseline. In contrast, changes in right ventricular outflow tract gradient and right ventricular dP/dt were highly significant at multiple timepoints, generally peaking immediately before or after reperfusion before reducing, but not returning to baseline in the neohepatic phase. Nine of 10 participants in this series demonstrated a degree of dynamic right ventricular outflow tract obstruction, which met criteria for hemodynamic significance (> 25 mmHg) in two participants. These changes were not materially affected by cardiac index.

Conclusions

Dynamic right ventricular outflow tract obstruction of varying severity appears common in patients undergoing orthotopic liver transplantation. These results are hypothesis generating and will form the basis of future prospective research.

Application of various surgical techniques in liver transplantation: a retrospective study

Background

Surgical techniques of liver transplantation have continually evolved and have been modified. We retrospectively analyzed a single-center case series and compared the advantages and disadvantages of each method.

Methods

Six-hundred and seventy-four recipients’ perioperative data were assessed and analyzed stratified by different surgical technics [modified classic (MC), modified piggyback (MPB) and classic piggyback (CPB)].

Results

MELD score and Child-Pugh scores was significantly higher in CPB groups (P=0.008 and 0.003, respectively). Anhepatic time in MPB group was longer than those in CPB group (P<0.05). The operation duration in MPB group was significantly longer than those in MC group and CPB group (P=0.003). Three patients had outflow obstruction (P=0.035). The overall survival in MPB group were better than those in MC group and CPB group in general comparison (P<0.001). In patients with preoperative creatine >120 µmol/L, the overall survival in MC group was worst (P<0.001). In patients with a high MELD score (>24), the overall survival in MPB group tended to be the best (P<0.001).

Conclusions

The advantages and disadvantages are different for these three surgical techniques. A reasonable operation technique should be adopted considering the patient's unique condition to ensure the stability of hemodynamics.

Caval reconstruction techniques in orthotopic liver transplantation

There are several caval reconstruction techniques currently in use for orthotopic liver transplantation. These include caval replacement or the conventional technique, performed with or without venovenous bypass, piggyback technique with anastomosis with two or three hepatic veins with or without cavotomy and modifications of the piggyback technique including end-to-side and side-to-side cavocaval anastomosis. There are few randomized controlled trials comparing the use of these techniques and our knowledge of their comparability is based on a few multi- and many single-center retrospective and prospective reviews. Although there are advantages and disadvantages for each technique, it is advisable that the surgeon perform the technique with which they have the most the experience and at which they are the most skilled as excellent outcomes can be obtained with any of the caval reconstruction options discussed.

Orthotopic liver transplantation without venovenous bypass using the conventional and piggyback techniques

INTRODUCTION

Orthotopic liver transplantation is a widely used procedure for the treatment of irreversible liver diseases for which there is no possibility of medical treatment. When this procedure is performed by the conventional technique, the retrohepatic vena cava is removed along with the native liver. The inferior vena cava (IVC) remains clamped until the revascularization of the graft, and in this period there is a reduction in the venous return, which may induce a fall by up to 50% in the cardiac output with hemodynamic instability and a fall in renal perfusion pressure. The use of a portal-femoral-axillary venovenous bypass system, in which the blood from the femoral and portal veins returns to the heart via the axillary vein propelled by a centrifugal pump, is intended to minimize the effects of the IVC clamping. In the piggyback (PB) technique, the native liver is removed and the IVC of the recipient is preserved and only partially clamped. We have employed both techniques without the use of venovenous bypass for 10 years. The objective of this study was to compare the results obtained from the use of the two techniques.

PATIENTS AND METHODS

A retrospective analysis was performed of 195 patients transplanted between 1999 and 2008: 125 by the conventional technique and 70, the PB technique. The intraoperative parameters were analyzed (surgical time, ischemia time, use of blood products, and diuresis), as well as intensive care support (duration of stay in intensive care unit and use of vasoactive drugs), period of intubation, length of hospital stay, renal function, graft function, postoperative complications, retransplantation, and patient survival.

RESULTS

The PB group showed a reduction in surgical time, warm ischemia time, the use of packed red blood cells concentrates, and fresh frozen plasma, as well as mortality at 30 days (P<.05). There were no differences in relation to cold ischemia time, intraoperative diuresis; length of stay and use of vasoactive drugs in the intensive care unit; the period of intubation; the duration of hospital stay; the renal function; the graft function; the need for reoperation; the incidence of sepsis, biliary complications, vascular complications; need for retransplantation; and 1-year mortality. The cumulative survival rate at 1 year was significantly better among the PB patients.

CONCLUSION

Orthotopic liver transplantation can be performed without venovenous bypass with good results, using either the conventional technique or the PB technique. Provided that there is no technical contraindication and a long ischemia period is not foreseen, the PB technique should be the technique of choice.

The beneficial impact of temporary porto-caval shunt in orthotopic liver transplantation: a single center analysis

The use of temporary porto-caval shunt (TPCS) has been shown to improve hemodynamic stability and renal function in patients undergoing orthotopic liver transplantation (OLT). We evaluated the impact of TPCS in OLT and analyzed the differences according to model for end-stage liver disease (MELD), donor risk index (DRI) and D-MELD. This is a retrospective single-center analysis of 148 consecutive OLT. Fifty-eight OLT were performed using TPCS and 90 without TPCS. Donor and recipient data with pre-OLT, intraoperative and postoperative variables were reviewed. Overall graft survival was 89.9% at 3 months and 81.7% at 1 year. Graft survival at 3 months and 1 year was 93.1% and 79.2%, respectively, in TPCS group versus 85.6% and 82.2%, respectively, in non-TPCS group (P = NS). Intraoperative packed red blood cells requirement was lower in TPCS group (7.5 ± 5.8 vs. 12.2 ± 14.2, P = 0.006) and non-TPCS group required higher intraoperative total dose of phenylephrine (16% vs. 28%, P = 0.04). TPCS group had lower 30-day postoperative mortality (1.7% vs. 10%, P = 0.04), no difference was observed at 90 days. Graft survival was lower in patients with high DRI; in this group graft loss was higher at 1 month (25% vs. 4.3%, P = 0.005) and 3 months (25% vs. 4.3%, P = 0.005) when TPCS was not used. TPCS improves perioperative outcome, this being more evident when high-risk grafts are placed into high-risk patients.

A single-center experience of 500 liver transplants using the modified piggyback technique by Belghiti

Over the past 4 decades, the surgical techniques of liver transplantation (LTx) have permanently evolved and been modified. Among these, the modified piggyback (MPB) technique by Belghiti offers specific advantages. The objective of this study was to present our single-center experience with the MPB technique in 500 cases. Recipients' perioperative data were prospectively collected and evaluated. Postoperative and specific complications, stay in the intensive and intermediate care unit, and the mortality rate with cause of death were analyzed. Most recipients were classified as Child C (49.1%). For the patients who underwent LTx for the first time, alcoholic (23.9%) and viral (22.2%) cirrhosis and hepatocellular carcinoma (15.1%) were the prevalent indications. The overall median warm ischemia time, anastomosis duration, and operative time were 45, 108, and 320 minutes, respectively. The median intraoperative blood loss was 1500 mL. A venovenous bypass was never needed to maintain hemodynamic stability. Only in a few cases was temporary inferior vena cava clamping necessary. Most prominent surgical complications were hemorrhage, hematoma, and wound dehiscence. Renal failure occurred in 6.2% of patients. The overall median stay in the intensive and intermediate care unit was 14 days. The mortality rates within 30 and 90 days were 6.3% and 13.3%, respectively. No technique-related death occurred. The MPB technique by Belghiti is a feasible and simple LTx technique. The caval flow is preserved during the anhepatic phase, and this minimizes the need for venovenous bypass or portocaval shunt. This technique requires only 1 caval anastomosis, which is easy to perform with a short anhepatic phase. To minimize the risk of outflow obstruction, attention should be paid by doing a wide cavocavostomy cranially to the donor inferior vena cava in a door-lock manner. This technique can be applied in almost all patients undergoing LTx for the first time and liver retransplantation as well.

Temporary porto-caval shunt utility during orthotopic liver transplantation

INTRODUCTION

In liver transplantation (OLT) a porto-caval shunt is a well-defined technique practiced by many surgeons in several centers.

METHODS

We considered 186 cadaveric OLT patients who underwent a cavo-cavostomy-type reconstruction; they were divided into two groups: those in whom we performed a porto-caval shunt (group A) and those in whose we did not (group B). We evaluated several variables: warm and total ischemia time, intraoperative blood and fresh frozen plasma transfusions, crystalloid and colloid requirements, blood loss, operative duration, hemodynamic intraoperative changes and diuresis, length of hospital stay, and creatinine values at days 1 and 2, and at discharge day.

RESULTS

Total and warm ischemic time differed significantly between the two groups. Infusion of blood, fresh frozen plasma, colloid, and crystalloid did not significantly differ. Blood loss was lower, and intraoperative diuresis was not significantly increased in group A subjects. Postoperative hospitalizations were 16.5 and 17.8 days and operative times, 504 and 611 minutes in the two groups. Both cardiac index and ejection fraction values during the anhepatic phase were significantly greater among group A than group B patients. PAD at the two phases was greater in group B. The PAS was significantly different only at reperfusion time. Creatinine values were significantly different at discharge. Better survival was shown for group A patients over group B subjects.

CONCLUSION

The results presented herein confirmed that a porto-caval shunt during OLT was a safe, useful expedient contributing to an improved hemodynamic status and a better time distribution in the various phases of liver transplantation.

The need for venovenous bypass in liver transplantation

Since introduction of the conventional liver transplantation (CLTx) by Starzl, which was based on the resection of recipient inferior vena cava (IVC) along the liver, the procedure has undergone several refinements. Successful use of venovenous bypass (VVB) was first introduced by Shaw et al., although in recent decades there has been controversy regarding the routine use of VVB during CLTx. With development of piggyback liver transplantation (PLTx), the use of caval clamping and VVB is avoided, leading to fewer complications related to VVB. However, some authors still advocate VVB in PLTx. The great diversity among centers in their use of VVB during CLTx, or even along the PLTx technique, has led to confusion regarding the indication setting for VVB. For this reason, we present an overview of the use of VVB in CLTx, the target of patients for whom VVB could be beneficial, and the needs assessment of VVB for patients undergoing PLTx. Recent studies have shown that with the advancement of surgical skills, refinement of surgical techniques, and improvements in anesthesiology, there are only limited indications for doing CLTx with VVB routinely. PLTx with preservation of IVC can be performed in almost all primary transplants and in the majority of re-transplantations without the need for VVB. Nevertheless, in a few selective cases with severe intra-operative hemodynamic instability, or with a failed test of transient IVC occlusion, the application of VVB is still justifiable. These indications should be judged intra-operatively and the decision is based on each center's preference.

Portocaval shunt throughout anhepatic phase in orthotopic liver transplantation for cirrhotic patients

The aim of this study was to assess whether the use of a temporary portocaval shunt (PCS) with inferior vena caval (IVC) preservation during orthotopic liver transplant procedures (OLT) in cirrhotic patients had any advantage. This work evaluated a group of cirrhotic patients who underwent liver-transplant between 1999 and 2006 with a temporary portocaval anastomosis and IVC preservation (PC group, n = 356) versus an historical group (no-PC group, n = 45) with only IVC preservation. We excluded cases of fulminant hepatitis, retransplants, portal vein thrombosis, or prior surgical portosystemic shunts. In both groups, graft reperfusion was achieved by simultaneous arterial and venous revascularization. Donor, recipient, and surgical characteristics were similar in both groups. The PCS group displayed significantly higher portovenous flow (PVF) than the no-PCS group (773 +/- 402 mL/min vs 555 +/- 379 mL/min, P = .004). We studied two subgroups: high PVF subgroup A (>800 mL/min; mean 1099 +/- 261 mL/min) and a low PVF subgroup B (<800 mL/min; mean 433 +/- 423 mL/min). In the high flow group (subgroup A) with PCS, a smaller number of blood units were required and better renal function was exhibited at the third postoperatory day. In contrast, no differences were observed among subgroup B between patients with or without PCS. The use of PCS with IVC preservation during the OLT enhanced the hemodynamic recipient status requiring a smaller number of blood units and displaying better renal function.

End-to-side caval anastomosis in adult piggyback liver transplantation

No consensus exists regarding the optimal reconstruction of the cavo-caval anastomosis in piggyback orthotopic liver transplantation (PB-LT). The aim of this study was to analyze our experience with end-to-side (ES) cavo-cavostomy. Outcome parameters were patient and graft survival and surgical complications. During the period 1995-2002 146 full-size PB-LT in 137 adult patients were performed with ES cavo-cavostomy without the routine use of temporary portocaval shunt (TPCS). In 12 patients (8%) this technique was used for implantation of second or third grafts. Veno-venous bypass was not used in any case and TPCS was performed only in eight patients (6%). One-, three- and five-yr patient and graft survival were 84%, 79% and 75%, and 81%, 74% and 69%, respectively. The median number of intraoperative transfusion of packed red blood cells (RBC) was 2.0 (range 0-33) and 30% of the patients (n = 43) did not require any RBC transfusion. Surgical complications of various types were observed after 49 LT (34%) and none of the complications was specifically related to the technique of ES cavo-cavostomy. Our experience indicates that PB-LT with ES cavo-cavostomy is a safe procedure, can safely be performed without the routine use of a TPCS, has a very low risk of venous outflow obstruction and can also be used effectively during retransplantations.

Conventional versus piggyback technique of caval implantation; without extra-corporeal veno-venous bypass. A comparative study

Conventional orthotopic liver transplantation (CON-LT) involves resection of recipient cava, usually with extra-corporeal circulation (veno-venous bypass, VVB), while in the piggyback technique (PC-LT) the cava is preserved. Along with a temporary portacaval shunt (TPCS), better haemodynamic maintenance is purported with PC-LT. A prospective, consecutive series of 384 primary transplants (2000-2003) were analysed, 138 CON-LT (with VVB) and 246 PC-LT (54 without TPCS). Patient/donor characteristics were similar in the two groups. PC-LT required less usage of fresh-frozen plasma and platelets, intensive care stay, number of patients requiring ventilation after day 1 and total days spent on ventilator. The results were not different when comparing, total operating and warm ischaemia time (WIT), red cell usage, requirement for renal support, day 3 serum creatinine and total hospital stay. TPCS had no impact on outcome other than WIT (P = 0.02). Three patients in PC-LT group (three of 246;1.2%) developed caval outflow obstruction (P = 0.02). There was no difference in short- or long-term graft or patient survival. PC-LT has an advantage over CON-LT unsing VVB with respect to intraoperative blood product usage, postoperative ventilation requirement and ITU stay. VVB is no longer required and TPCS may be used selectively in adult transplantation.

Portacaval Shunt and Inferior Vena Cava Preservation in Orthotopic Liver Transplantation

The aim was to study the advantages of the use of a temporary portacaval shunt (PCS) with inferior vena cava (IVC) preservation during the piggyback technique for the anhepatic phase of orthotopic liver transplantation (OLT) performed in cirrhotic patients. Two groups of cirrhotic patients who underwent OLT with piggyback technique were compared; one with a PCS (n = 57) and the other, without PCS (n = 54). Patients with fulminant hepatitis, retransplantation, portal thrombosis, and previous portosystemic shunts were excluded. In both groups graft reperfusion was achieved by simultaneous arterial and venous revascularization. Donor, recipient, and surgical characteristics were similar in both groups. The PCS group had a significantly higher portal venous flow (PVF) than the no-PCS group (773 +/- 402 mL/min vs 555 +/- 379 mL/min, P = .004). Therefore, two subgroups were studied; the high PVF subgroup A (>800 mL/min), mean 1099 +/- 261 mL/min, and the low PVF subgroup B (<800 mL/min), mean 433 +/- 423 mL/min. Subgroup A, who were treated with PCS, required fewer blood transfusions and displayed better postoperative renal function; whereas, no differences were observed among subgroup B patients with versus without PCS. In conclusion, the use of a temporary PCS with piggyback technique during OLT in cirrhotics has advantages in patients who still maintain a high portal venous flow.

Venous outflow reconstructions with the piggyback technique in liver transplantation: a single-center experience of 431 cases

The ideal method of venous outflow reconstruction with the piggyback technique (PB) in orthotopic liver transplantation (OLT) is not well-established. The complications related to PB in 431 primary OLTs were analyzed comparing the orifices used for the anastomosis (cuff of the recipient left and middle hepatic veins [LM], LM with a >1 cm cavoplasty [LM+], or also including the right hepatic vein [LMR]). Treatment strategies and outcome were also evaluated. Twenty patients (4.6%) experienced complications: 13 of 120 (10.8%) with LM, four of 225 (1.8%) with LM+, and three of 86 (3.5%) with LMR (LM versus LM+: P < 0.0001; LM versus LMR: P = NS; LM+ versus LMR = NS). Balloon dilation was successful in 10 of 13 cases in which it was attempted (77%). Eight patients required retransplantation (40%). Three patients (0.7%) died from causes linked to stenosis. Five-year survival of patients with and without complications was 75% and 79%, respectively (P =NS); 5-year graft survival was 50% and 76%, respectively (P = 0.001). The stump formed by the recipient left and middle hepatic veins with a transversal incision >1 cm of the caval wall constantly provides an adequate width for the caval anastomosis with the PB.

Liver transplantation with preservation of the inferior vena cava. A comparison of conventional and piggyback techniques in adults

The aim of this study is to analyse a single centre's experience with two techniques of liver transplantation (OLT), conventional (CON-OLT) and piggyback (PB-ES), and to compare outcome in terms of survival, morbidity, mortality and post-operative liver function as well as operative characteristics. A consecutive series (1994-2000) of 167 adult primary OLT were analysed. Ninety-six patients had CON-OLT and 71 patients had PB-ES. In PB-ES group two revascularization protocols were used. In the first protocol reperfusion of the graft was performed first via the portal vein followed by the arterial anastomosis (PB-seq). In the second protocol the graft was reperfused simultaneously via portal vein and hepatic artery (PB-sim). One-, 3- and 5-yr patient survival in the CON-OLT and PB-ES groups were 90, 83 and 80%, and 83, 78 and 78%, respectively (p = ns). Graft survival at the same time points was 81, 73 and 69%, and 78, 69 and 65%, respectively (p = ns). Apart from the higher number of patients with cholangitis and sepsis in CON-OLT group, morbidity, retransplantation rate and post-operative liver and kidney function were not different between the two groups. The total operation time was not different between both groups (9.4 h in PB-ES vs. 10.0 h in CON-OLT), but in PB-ES group cold and warm ischaemia time (CIT and WIT), revascularization time (REVT), functional and anatomic anhepatic phases (FAHP and AAHP) were significantly shorter (8.9 h vs. 10.7 h, 54 min vs. 63 min, 82 min vs. 114 min, 118 min vs. 160 min and 87 min vs. 114 min, respectively, p < 0.05). RBC use in the PB-ES group was lower compared to the CON-OLT group (4.0 min vs. 10.0 units, p < 0.05). Except for WIT and REVT there were no differences in operative characteristics between PB-Sim and PB-Seq groups. The WIT was significantly longer in PB-Sim group compared with PB-Seq group (64 min vs. 50 min, p < 0.05); however REVT was significantly shorter in PB-Sim group (64 min vs. 97 min, p < 0.05). Results of this study show that both techniques are comparable in survival and morbidity; however PB-ES results in shorter AAHP, FAHP, REVT and WIT as well as less RBC use. In the PB-ES group there seems to be no advantage for any of the revascularization protocols.

Massive gastrointestinal bleeding complicating portal vein cross-clamping during liver transplantation

This case report describes the occurrence of massive upper gastrointestinal hemorrhage immediately after cross-clamping of the inferior vena cava and hepatic portal vein. This case suggests that acute intraoperative hemorrhage from a varix should always be a consideration before liver transplantation in patients who have a history of upper gastrointestinal bleeding.

IMPLICATIONS

A case of severe bleeding during liver transplantation is described in a patient who had a history of bleeding from the stomach before surgery. The importance of understanding surgical options and the ability to provide rapid massive transfusion in the management of this complication are discussed.

Techniques of orthotopic liver transplantation

BACKGROUND

Throughout the history of liver transplantation many improvements have been made in the field of surgical technique. It is beyond the scope of this paper to review all aspects of surgical technique in liver transplantation; thus, in this review we focus on the description of our current technique in most cases, which is orthotopic liver transplantation with preservation of the inferior vena cava and temporary portocaval shunt. We advocate this technique because it has been demonstrated that it achieves better haemodynamic stability during the anhepatic phase, transfusion can be reduced and renal function is improved. The different options for vascular anastomoses are described, particularly the options for arterial anastomoses in case of finding a non-adequate recipient hepatic artery. Technical possibilities for patients with preoperative portal vein thrombosis and the procedure in case of domino or sequential liver transplantation are further explained.

Cavocaval adult liver transplantation and retransplantation without venovenous bypass and without portocaval shunting: a prospective feasibility study in adult liver transplantation

BACKGROUND

The original method of liver transplantation (LT) included recipient inferior vena cava (IVC) resection and the use of extracorporeal venovenous bypass (VVB). Refinements in technique permit transplantation to be done with IVC preservation and without VVB use.

MATERIAL AND METHODS

Between November 1993 and November 2000, 202 consecutive grafts were performed in 188 adults (>/=16 years of age). Twelve patients (6.4%) received two and three retransplants (re-LT). Split grafting was performed 19 times (19 of 202 grafts, 9.4%). Risk factors included United Network of Organ Sharing status I (n=30, 16%), previous right upper abdominal surgery (n=32, 17.1%), caudate lobe encirclement of IVC (n=65, 32.2%), IVC (n=24, 11.9%), and splanchnic venous modification (n=58, 30.9%), transjugular intrahepatic portosystemic stent shunt (n=34, 16.8%), giant (>5 kg) liver tumor (n=6, 3%), septic necrosis of the caudate lobe (n=1, 0.5%), and previous cavocaval (n=13, 6.4%) or classical LT (n=5, 2.5%).

RESULTS

IVC preservation, avoidance of IVC cross clamping and of VVB use were possible in 98.9%, 93%, and 99.5% of 183 primary LT and in 89.5%, 84.2%, and 89.5% of 19 re-LT. Temporary portocaval shunting was never applied. Perioperative mortality was 1.2%. There was no allotransfusion in 73 (36%) grafts and 45 (22%) patients were immediately extubated. Permanent hepatic vein and caval problems were encountered in three (1.5%) grafts. One patient needed stent placement to treat IVC stenosis. Actual 3- and 12-month patient survival for whole, re-LT, and right-lobe split LT groups were 94.7%, 94.1%, 94.7%, 88.2%, 94.1%, and 89%. Three-month graft survival rates for these groups were 92.6%, 94.7%, and 84.2%.

CONCLUSIONS

LT with IVC preservation and without VVB use and portocaval shunting is possible in nearly all primary transplants and in the majority of re-LT.

Comparison of hepatic artery and portal vein reperfusion during orthotopic liver transplantation

BACKGROUND

During orthotopic liver transplantation (OLT), it is standard procedure to reperfuse the liver via the portal vein (PV) despite having a lower oxygen content and perfusion pressure than the hepatic artery (HA). There are no published studies that describe graft function and outcome when the HA is used for reperfusion. We report a retrospective comparison of graft outcome after HA or PV reperfusion when the piggyback technique was used.

METHODS

We identified 26 patients who had undergone OLT with HA reperfusion and 26 patients reperfused via the PV. Demographics, primary diagnosis, surgeon, warm and cold ischemic times, and blood product use were recorded. In each patient, whole blood lactate concentration, prothrombin time (PT), and alanine aminotransferase (ALT) were measured at defined time points during and after surgery as indices of graft lactate metabolism, synthetic function, and reperfusion injury, respectively. Thirty-day and 1-year outcome data were recorded. Data were compared between the HA and PV groups.

RESULTS

Demographics, blood product use, primary diagnosis, cold ischemic time, and surgeon were similar between the groups. Warm ischemic time was longer in the HA group (mean [SD] HA 51.2 [14.7], PV 40 [9.1] min, P=0.002). Blood lactate concentrations were similar at all time points. There was no difference in 24-hr postoperative PT between the groups (median [InterQuartile (IQ) range] HA 17.5 [16-28.3], PV 19 [16-24] sec, P=0.85). Peak postoperative ALT values were comparable (median [IQ range] HA 1031 [668-1701], PV 1107 [754-1824] IU/ml, P=0.78). There were no statistically significant differences in 30-day or 1-year mortality, but more early deaths occurred in the HA group. Using our data, we calculated that a prospective randomized trial would need approximately 300 patients to be sure that mortality was the same with both techniques.

CONCLUSION

We have demonstrated no clinically or statistically significant differences in indices of graft function, reperfusion injury, or outcome between primary HA or PV reperfusion.

Feasibility and limits of caval-flow preservation during liver transplantation

As promoters of orthotopic liver transplantation (OLT) with preservation of caval flow, we reviewed our 8-year experience to assess the feasibility and limits of this technique. Preservation of caval flow during OLT, which improves intraoperative hemodynamic stability, was not considered feasible in a significant proportion of transplant recipients. When transient clamping of caval flow is required, causes and consequences of this clamping during all phases of the procedure were not reported. Between 1991 and 1998, a total of 275 OLTs using a whole graft were performed in 259 patients with a policy consisting of a systematic attempt to preserve inferior vena cava (IVC) and caval flow. Preservation of IVC flow was possible in all cases, and no procedure was converted to the conventional technique. Caval flow was maintained throughout the procedure in 246 procedures (90%). Temporary IVC cross-clamping was required in 24 cases during hepatectomy because of difficult dissection and in 5 cases after graft reperfusion because of outflow obstruction; none required the use of a venovenous shunt. IVC cross-clamping during hepatectomy was required more frequently in cases of a large liver, with a mean duration of 11 +/- 4 minutes, but without significant influence on early postoperative risk, including one graft failure (4%) and one postoperative death (4%). Conversely, IVC cross-clamping after reperfusion, with a mean duration of 23 +/- 5 minutes, was associated with four graft failures (80%) and four deaths (80%). We conclude that IVC preservation is feasible in almost all candidates, allowing the use of split livers from cadaveric or living donors independently from their underlying disease. Although preservation of caval flow was possible in the large majority of cases, transient IVC cross-clamping during hepatectomy was well tolerated in contrast to caval clamping after graft reperfusion. Therefore, if necessary, we recommend transient IVC cross-clamping to perform a large cavocaval anastomosis.

Temporary portocaval shunt during liver transplantation with vena cava preservation. Results of a prospective randomized study

This study aims to determine whether the use of a temporary portocaval shunt (PCS) improves hemodynamic and metabolic evolution during orthotopic liver transplantation (OLT). Preservation of the vena cava during OLT has gained wide acceptance. However, benefits of adding a temporary PCS to the piggyback technique during the anhepatic phase in patients with cirrhosis have not been shown. Eighty patients with cirrhosis were studied prospectively. They were randomly distributed into two groups: patients with a temporary PCS (n = 40) and those without a PCS (n = 40). In all cases, the piggyback technique was used. Hemodynamic profiles and biochemical data during OLT and clinical evolution after OLT were evaluated. Preoperative data were similar in both groups. Surgical time also was similar (403 +/- 77 v 387 +/- 56 minutes; P = .3). Red blood cell requirements were lower in the PCS group (2.3 +/- 2.5 v 3.3 +/- 2.9 units), although differences were not significant. In the PCS group, 45% of patients did not need red blood cell transfusion, whereas in the other group, only 22% were not administered a transfusion (P = .03). During the anhepatic phase, the decrease in cardiac output was lower in the PCS group (-9.6% v -19%; P = .05), whereas diuresis during the anhepatic phase was greater in the PCS group (3.6 +/- 2.97 v 2.1 +/- 1.38 mL/kg/h; P = .005). There were no differences in liver biochemical parameters during the first 3 postoperative days. Nevertheless, creatinine levels increased significantly during this period only in the no-PCS group. The use of a temporary PCS during OLT improves hemodynamic status, reduces intraoperative transfusion requirements, and preserves renal function during and after OLT.

The clinical importance of conventional and quantitative liver function tests in liver transplantation

The advantages and disadvantages of using monoethylglycinexylidide (MEGX), the major metabolite of lidocaine, as a probe of hepatic function in liver transplantation are reviewed. A 'real time' test of liver function should give a measure of current hepatocellular capacity rather than reflect past damage. The hepatic metabolism of lidocaine to MEGX is the basis of a flow-dependent dynamic test of liver function. In pre-transplantation patients, data from this MEGX test support its role in assessing the risk of morbidity and mortality. In assessing the liver transplant donor, there are differences concerning its apparent usefulness and these must be resolved. In the liver transplant recipient, this MEGX test is also useful for measuring real-time hepatic metabolizing activity, and low MEGX values reflect the clinical condition of the patient. At present, however, this test has several limitations. Therefore, a comprehensive evaluation, not only by the MEGX test but also by a combination of other conventional liver function tests (biochemical parameters, etc.), or with histological evaluation, is thought to be desirable for deciding whether a liver transplantation should be carried out or not.