Does caval reconstruction technique affect early graft function after liver transplantation? A preliminary analysis

Adult 10-year survivors after liver transplantation: a single-institution experience over 40 years

Liver transplantation (LT) represents the best cure for several acute and chronic liver diseases. Several studies reported excellent mid-term survivals after LT. However, lesser evidence has been reported on very long (10- and 20-year) follow-up results. This study aims to analyze the monocentric LT experience of the Sapienza University of Rome to identify the pre-operatively available parameters limiting a 10-year post-transplant survival. A total of 491 patients transplanted between 1982 and 2012 were enrolled. The cohort was split into two groups, namely the Short Surviving Group (< 10 years; n = 228, 46.4%) and the Long Surviving Group (≥ 10 years; n = 263, 53.6%). Several differences were reported between the two groups regarding initial liver function, surgical techniques adopted, and immunosuppression. Four variables emerged as statistically relevant as independent risk factors for not reaching at least 10 years of follow-up: recipient age (OR = 1.02; P = 0.01), donor age (OR = 1.01; P = 0.03), being transplanted during the eighties (OR = 6.46; P < 0.0001) and nineties (OR = 2.63; P < 0.0001), and the UNOS status 1-2A (OR = 2.62; P < 0.0001). LT confirms to be an extraordinary therapy for several severe liver diseases, consenting to reach in half of the transplanted cases even more than 20 years of follow-up. The initial liver function and the donor and recipient ages are relevant in impacting long-term survival after transplantation. A broad commitment from many professional groups, including surgeons, hepatologists, and anesthesiologists, is necessary. The achievement of excellent results in terms of long-term survival is proof of the effectiveness of this multidisciplinary collaboration.

Comparison of the modified piggyback with standard piggyback and conventional orthotopic liver transplantation techniques: a network meta-analysis

BACKGROUND

In conventional orthotopic liver transplantation (OLT), the recipient's retrohepatic inferior vena cava (IVC) is completely clamped and replaced with the donor IVC. The piggyback technique has been used to preserve venous return, either via an end-to-side or standard piggyback (SPB), or via a side-to-side or modified piggyback (MPB) anastomosis, using a venous cuff from the recipient hepatic veins with partially clamping and preserves the recipient's inferior vena cava. However, whether these piggyback techniques improve the efficacy of OLT is unclear. To address the low quality of the available evidence, we performed a meta-analysis to compare the efficacy of conventional, MPB, and SPB techniques.

METHODS

Literature was searched in Medline and Web of Science databases for relevant articles published until 2021 without any time restriction. A Bayesian network meta-analysis was performed to compare the intra- and postoperative outcomes of conventional OLT, MPB, and SPB techniques.

RESULTS

Forty studies were included, comprising 10,238 patients. MPB and SPB had significantly shorter operation times and fewer transfusions of red blood cell and fresh frozen plasma than conventional techniques. However, there were no differences between MPB and SPB in operation time and blood product transfusion. There were also no differences in primary non-function, retransplantation, portal vein thrombosis, acute kidney injury, renal dysfunction, venous outflow complications, length of hospital and intensive care unit stay, 90-day mortality rate, and graft survival between the three techniques.

CONCLUSION

MBP and SBP techniques reduce the operation time and need for blood transfusion compared with conventional OLT, but postoperative outcomes are similar. This indicates that all techniques can be implemented based on the experience and policy of the transplant center.

Complex Liver Transplantation Using Venovenous Bypass With an Atypical Placement of the Portal Vein Cannula

In liver transplantation (LT) medical literature, venovenous bypass (VVB) with the interposition of a venous graft attached to the inferior mesenteric vein (IMV) or to the splenic vein (SV) has not been reported previously. Here, we report the decompression of the portomesenteric compartment in 2 patients with complex cases of orthotopic LT. A femoroaxillary percutaneous VVB was installed prior to abdominal opening to decompress massive collateral veins in the abdominal wall. In the first patient, the IMV was connected to a donor vein graft with a lateroterminal anastomosis, and the distal part of the vein graft was cannulated and connected to the VVB. In the second patient, because of the excessive size of the spleen, it was necessary to perform a splenectomy to gain sufficient space in the abdomen to implant the new liver. The SV was connected to a donor vein graft with a terminoterminal anastomosis, and the distal part of the vein graft was cannulated and connected to the VVB. In both patients, the decompression of the portomesenteric compartment was crucial to reduce portal hypertension and to access the hepatic hilum, where the dissection was very complex due to previous major surgeries. In conclusion, VVB with the interposition of a venous graft attached to the IMV or to the SV during LT is a safe and simple technique, and it may be useful for patients needing VVB with no standard access to the portal compartment, particularly in the case of severe portal hypertension and re-LTs.

Piggyback or Cava Replacement: Which Implantation Technique Protects Liver Recipients From Acute Kidney Injury and Complications?

The cava-preserving piggyback (PB) technique requires only partial cava clamping during the anhepatic phase in liver transplantation (LT) and, therefore, maintains venous return and may hemodynamically stabilize the recipient. Hence, it is an ongoing debate whether PB implantation is more protective from acute kidney injury (AKI) after LT when compared with a classic cava replacement (CR) technique. The aim of this study was to assess the rate of AKI and other complications after LT comparing both transplant techniques without the use of venovenous bypass. We retrospectively analyzed the adult donation after brain death LT cohort between 2008 and 2016 at our center. Liver and kidney function and general outcomes including complications were assessed. Overall 378 transplantations were analyzed, of which 177 (46.8%) were performed as PB and 201 (53.2%) as CR technique. AKI occurred equally often in both groups. Transient renal replacement therapy was required in 22.6% and 22.4% comparing the PB and CR techniques (P = 0.81). Further outcome parameters including the complication rate were similar in both cohorts. Five-year graft and patient survival were comparable between the groups with 81% and 85%, respectively (P = 0.48; P = 0.58). In conclusion, both liver implantation techniques are equal in terms of kidney function and overall complications following LT.

The Impact of Implantation Time During Liver Transplantation on Outcome: A Eurotransplant Cohort Study

Supplemental digital content is available in the text.

Background

The liver graft quickly rewarms during transplantation when the vascular anastomoses are being performed, potentially impacting on outcomes.

Methods

We investigated the relationship between implantation time and outcome in 5223 recipients of deceased-donor livers transplanted in Eurotransplant (2004-2013). Cox regression analyses were corrected for donor, preservation, and recipient variables. Transplant loss represents all-cause graft failure.

Results

Median implantation time was 41 minutes (interquartile range, 34-51). Implantation time independently associated with transplant loss (adjusted hazard ratio, 1.04 for every 10-minute increase; 95% confidence interval, 1.01-1.07; P = 0.007). The magnitude of the implantation time effect was comparable to the effect of each additional hour of cold ischemia (adjusted hazard ratio, 1.03; 95% confidence interval, 1.02-1.05; P < 0.001). The effect was most pronounced early posttransplant with no evidence of a significant effect beyond 3 months. A similar detrimental effect of implantation time was seen for graft and patient survivals. The increased risk for transplant loss in livers donated after circulatory determination of death could be attributed to donor warm ischemia time.

Conclusions

Implantation time associates with inferior liver transplant outcome in a continuous way. These findings need confirmation and further study of confounding factors is needed so steps toward improving outcomes can be made.

Liver Transplantation Without Venovenous Bypass: Does Surgical Approach Matter?

Background

The use of venovenous bypass in liver transplantation has declined over time. Few studies have examined the impact of surgical approach in cases performed exclusively without venovenous bypass. We hypothesized that advances in liver transplant anesthesia and perioperative care have minimized the importance of surgical approach in the modern era.

Methods

Deceased donor liver transplants at the University of Toronto from 2000 to 2015 were reviewed, all performed without venovenous bypass. First, an unadjusted analysis was performed comparing perioperative outcomes and graft/patient survival for 3 different liver transplant techniques (caval interposition, piggyback, side-to-side cavo-cavostomy). Second, a propensity-matched analysis was performed comparing caval interposition to caval-preserving techniques.

Results

One thousand two hundred thirty-three liver transplants were included in the study. On unadjusted analysis, blood loss, transfusion requirement, postoperative complications, and graft/patient survival were equivalent for the 3 different techniques. To account for possible confounding patient variables, propensity matching was performed. Analysis of the propensity-matched cohorts also demonstrated similar outcomes for caval interposition versus caval-preserving approaches.

Conclusions

In the modern era at centers with a multidisciplinary team, the importance of specific liver transplant technique is minimized. Full or partial cross-clamping of the inferior vena cava is feasible without the use of venovenous bypass.

Comparison of three caval reconstruction techniques in orthotopic liver transplantation: A retrospective review

BACKGROUND

Classic caval reconstruction during liver transplantation involves complete cross-clamping and resection of the recipient inferior vena cava (IVC) followed by donor IVC interposition. Other techniques preserve the IVC, with piggyback (PB) to the hepatic veins or side-to-side (SS) caval anastomosis. Avoidance of cross-clamping may be beneficial for minimizing hemodynamic instability and transfusion requirements.

METHODS

Retrospective review of a provincial transplant database (2007-2011). MELD score was used to measure disease severity. Intraoperative blood loss and volume resuscitation were compared between three caval reconstruction techniques using ANOVA.

RESULTS

200 deceased-donor transplants (Classic:58, PB:72, SS:70) were included. Baseline disease severity was equal. Mean case duration was shorter in the PB technique (Classic:366, PB:306, SS:385 min, p < 0.001). Despite similar blood loss, there was significantly less cell saver return, FFP, platelets, and overall resuscitation volume (Classic:12.8, PB:9.5, SS:13.2 L, p = 0.001) utilized in the piggyback technique.

CONCLUSIONS

The PB technique was faster and used less cell saver return, FFP and platelets, despite similar blood loss. Availability of different caval reconstruction techniques allows for a breadth of options in difficult cases.

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.

Renal support during liver transplantation: when to consider it?

Patients undergoing orthotopic liver transplantation constitute a difficult-to-treat population. They often have multiorgan dysfunction: acute kidney injury, severe water-electrolyte and acid-base imbalances, systemic inflammatory responses, thrombocytopenia, as well as abnormalities of coagulation and fibrinolysis. All of these disorders may be further exacerbated by the surgical procedure, which is lengthy and technically complex, requiring massive blood product and other fluid infusions with a high risk to develop severe lactic acidosis, hyperkalemia, or cerebral edema. These considerations provide a rationale to institute intraoperative renal replacement therapy (ioRRT), at least for the most critically ill, namely, patients with kidney dysfunction, or those in whom one anticipates intraoperative clinical and technical problems. This article discusses the most common indications and strategies for ioRRT, examining their advantages and disadvantages as well as current experiences.