Risk of venous congestion in live donors of extended right liver graft

Donor safety of remnant liver volumes of less than 30% in living donor liver transplantation: A systematic review and meta-analysis

PURPOSE

This meta-analysis aimed to investigate the acceptability of donor remnant liver volume (RLV) to total liver volume (TLV) ratio (RLV/TLV) being <30% as safe in living donor liver transplantations (LDLTs).

METHODS

Online databases were searched from January 2000 to June 2022. Pooled odds ratios (ORs) and standardized mean differences (SMDs) with 95% confidence intervals (CIs) were calculated using fixed- or random-effects model.

RESULTS

One prospective and seven retrospective studies comprising 1935 patients (164 RLV/TLV <30% vs. 1771 RLV/TLV ≥30%) were included. Overall (OR = 1.82; 95% CI [1.24, 2.67]; p = .002) and minor (OR = 1.88; 95% CI [1.23, 2.88]; p = .004) morbidities were significantly lower in the RLV/TLV ≥30% group than in the RLV/TLV <30% group (OR = 1.82; 95% CI [1.24, 2.67]; p = .002). No significant differences were noted in the major morbidity, biliary complications, and hepatic dysfunction. Peak levels of bilirubin (SMD = .50; 95% CI [.07, .93]; p = .02) and international normalized ratio (SMD = .68; 95% CI [.04, 1.32]; p = .04) were significantly lower in the RLV/TLV ≥ 30% group than in the RLV/TLV <30% group. No significant differences were noted in the peak alanine transferase and aspartate transaminase levels and hospital stay.

CONCLUSIONS

Considering the safety of the donor as the top priority, the eligibility of a potential liver donor in LDLT whose RLV/TLV is expected to be <30% should not be accepted.

Splenic Artery Ligation: An Ontable Bail-Out Strategy for Small-for-Size Remnants after Major Hepatectomy: A Retrospective Study

It has been reported that the prevention of acute portal overpressure in small-for-size liver grafts leads to better postoperative outcomes. Accordingly, we aimed to investigate the feasibility of the technique of splenic artery ligation in a case series of thirteen patients subjected to major liver resections with evidence of small-for-size syndrome and whether the maneuver results in the reduction of portal venous pressure and flow. The technique was successful in ten patients, with splenic artery ligation alleviating portal hypertension significantly. Three patients required the performance of a portocaval shunt for the attenuation of portal hypertension. Portal inflow modulation via splenic artery ligation is a technically simple technique that can prove useful in the context of major hepatectomies as well as in liver transplantations and the early evaluation and modification of portal venous pressure post hepatectomy can be used as a practical tool to guide the effect of the intervention.

Deportalization, Venous Congestion, Venous Deprivation: Serial Measurements of Volumes and Functions on Morphofunctional 99mTc-Mebrofenin SPECT-CT

The objective was to assess the changes in regional volumes and functions under venous-impaired vascular conditions following liver preparation. Twelve patients underwent right portal vein embolization (PVE) (n = 5) or extended liver venous deprivation (eLVD, i.e., portal and right and middle hepatic veins embolization) (n = 7). Volume and function measurements of deportalized liver, venous-deprived liver and congestive liver were performed before and after PVE/eLVD at days 7, 14 and 21 using 99mTc-mebrofenin hepatobiliary scintigraphy with single-photon emission computed tomography and computed tomography (99mTc-mebrofenin SPECT-CT). Volume and function progressed independently in the deportalized liver (p = 0.47) with an early decrease in function (median −18.2% (IQR, −19.4–−14.5) at day 7) followed by a decrease in volume (−19.3% (−22.6–−14.4) at day 21). Volume and function progressed independently in the venous deprived liver (p = 0.80) with a marked and early decrease in function (−41.1% (−52.0–−12.9) at day 7) but minimal changes in volume (−4.7% (−10.4–+3.9) at day 21). Volume and function progressed independently in the congestive liver (p = 0.21) with a gradual increase in volume (+43.2% (+38.3–+51.2) at day 21) that preceded a late and moderate increase in function at day 21 (+34.8% (−8.3–+46.6)), concomitantly to the disappearance of hypoattenuated congestive areas in segment IV (S4) on CT, initially observed in 6/7 patients after eLVD and represented 35.3% (22.2–46.4) of whole S4 volume. Liver volume and function progress independently whatever the vascular condition. Hepatic congestion from outflow obstruction drives volume increase but results in early impaired function.

A systematic review of small for size syndrome after major hepatectomy and liver transplantation

BACKGROUND

Major hepatectomy (MH) and particular types of liver transplantation (LT) (reduced size graft, living-donor and split-liver transplantation) lead to a reduction in liver mass. As the portal venous return remains the same it results in a reciprocal and proportionate rise in portal venous pressure potentially resulting in small for size syndrome (SFSS). The aim of this study was to review the incidence, diagnosis and management of SFSS amongst recipients of LT and MH.

METHODS

A systematic review was performed in accordance with the 2010 Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. The following terms were used to search PubMed, Embase and Cochrane Library in July 2019: ("major hepatectomy" or "liver resection" or "liver transplantation") AND ("small for size syndrome" or "post hepatectomy liver failure"). The primary outcome was a diagnosis of SFSS.

RESULTS

Twenty-four articles met the inclusion criteria and could be included in this review. In total 2728 patients were included of whom 316 (12%) patients met criteria for SFSS or post hepatectomy liver failure (PHLF). Of these, 31 (10%) fulfilled criteria for PHLF following MH. 8 of these patients developed intractable ascites alongside elevated portal venous pressure following MH indicative of SFSS.

CONCLUSION

SFSS is under-recognised following major hepatectomy and should be considered as an underlying cause of PHLF. Surgical and pharmacological therapies are available to reduce portal congestion and reverse SFSS.

Scoring criteria for determining the safety of liver resection for malignant liver tumors

BACKGROUND

Liver resection has become safer as it has become less invasive. However, the minimum residual liver volume (RLV) required to maintain homeostasis is unclear. Furthermore, the formulae used to calculate standard liver volume (SLV) are complex.

AIM

To review previously reported SLV formulae and the methods used to evaluate the minimum RLV, and explore the association between liver volume and mortality.

METHODS

A systematic review of Medline, PubMed, and grey literature was performed. References in the retrieved articles were cross-checked manually to obtain further studies. The last search was conducted on January 20, 2019. We developed an SLV formula using data for 86 consecutive patients who underwent hepatectomy at our institution between July 2009 and August 2011.

RESULTS

Linear regression analysis revealed the following formula: SLV (mL) = 822.7 × body surface area (BSA) − 183.2 (R² = 0.419 and R = 0.644, P < 0.001). We retrieved 25 studies relating to SLV formulae and 12 studies about the RLV required for safe liver resection. Although the previously reported formulae included various coefficient and constant values, a simplified version of the SLV, the common SLV (cSLV), can be calculated as follows: cSLV (mL) = 710 or 770 × BSA. The minimum RLV for normal and damaged livers ranged from 20%-40% and 30%-50%, respectively. The Sapporo score indicated that the minimum RLV ranges from 35%-95% depending on liver function.

CONCLUSION

We reviewed SLV formulae and the minimum RLV required for safe liver resection. The Sapporo score is the only liver function-based method for determining the minimum RLV.

Right anterior section graft for living-donor liver transplantation: A case report

RATIONALE

In living-donor liver transplantation (LDLT), the right lobe graft is commonly utilized to prevent small-for-size syndrome, despite the considerable donor morbidity. Conversely, the feasibility of the left lobe graft and the right posterior section graft in smaller-sized recipients is now commonly employed with comparable outcomes to right lobe grafts. The efficacy of the right anterior section graft has rarely been reported.

PATIENT CONCERNS

A 56-year-old man, a heavy alcoholic beverage drinker for 20 years, presented in the emergency department with massive ascites and lethargy. He was previously admitted twice due to bleeding esophageal varices.

DIAGNOSIS

He was diagnosed with hepatic encephalopathy coma due to alcoholic liver cirrhosis. The Child-Turcotte-Pugh score was 11 (class C), and the Model for End-stage Liver Disease score was 21.62.

INTERVENTION

A LDTL was offered to the patient as the best treatment option available. The patient's 26-year-old son was found to be the only donor-compatible candidate for the LDTL.Preoperatively, the right lobe of the donor occupied 76.2% of the total liver volume exposing the donor to a small residual liver volume. The right posterior section and left lobe volumes were insufficient, providing a graft-to-recipient weight ratio of 0.42% and 0.38%, respectively. However, the right anterior section could fulfill an acceptable GRWR of 0.83%. Thus, a living donor right anterior sectionectomy was performed.

OUTCOMES

Clinical signs and symptoms and liver function improved following anterior section graft transplantation without complications.

LESSON

The procurement of anterior section graft is technically feasible in selected patients, especially in high-volume liver centers.

Randomized trial on extended versus modified right lobe grafts in living donor liver transplantation

Despite advances in the practice of living donor liver transplantation (LDLT), the optimum surgical approach with respect to the middle hepatic vein (MHV) in right lobe LDLT remains undefined. We designed a randomized trial to compare the early postoperative outcomes in recipients and donors between extended right lobe grafts (ERGs; transection plane was maintained to the left of MHV and division of MHV performed beyond the segment VIII vein) and modified right lobe grafts (MRGs; transection plane was maintained to the right of MHV; the segment V and VIII drainage was reconstructed using a conduit of recipient portal vein). Eligible patients (n = 86) were prospectively randomized into the ERG arm (n = 43) and the MRG arm (n = 43) at the beginning of donor hepatectomy. The primary endpoint considered in this equivalence trial was patency of the MHV or the reconstructed "neo-MHV" in the recipient. The secondary endpoints included biochemical parameters, postoperative complications, mortality in recipients as well as donors and volume regeneration of remnant liver in donors, measured at 2 months. The patency of the MHV was comparable in the ERG and MRG arms (90.7% versus 81.4%; difference, 9.3%; 95% confidence interval [CI], -5.8 to 24.4; z score, 1.245; P = 0.21). Volume regeneration of the remnant liver in donors was significantly better in the MRG arm (111.3% versus 87.3%; mean difference, 24%; 95% CI, 14.6-33.3; P < 0.001). The remaining secondary endpoints in donors and recipients were similar between the 2 arms. To conclude, MRG with reconstructed neo-MHV has comparable patency to native MHV in ERG and confers equivalent graft outflow in the recipient. Furthermore, it allows better remnant liver regeneration in the donor at 2 months. Liver Transplantation 24 888-896 2018 AASLD.