Temporary portocaval shunt in orthotopic liver transplantation: need for a standardized approach?

Changes in Blood Potassium after Reperfusion during Living-Donor Liver Transplantation: An Exploratory Study

The incidence of hyperkalemia (>5.5 mEq/L) or high blood potassium (5–5.5 mEq/L) during living-donor liver transplantation (LDLT) is reported to be more than 10%. It occurs more frequently in the early post-reperfusion period and is a major cause of post-reperfusion arrhythmia and cardiac arrest. Unlike deceased-donor liver transplantation, the pattern of blood potassium changes immediately after reperfusion has not been described in LDLT. From January 2021 to March 2021, fifteen consecutive patients were enrolled. Baseline blood potassium was measured from blood samples obtained 10-min (T_-10) and immediately before (T₀) reperfusion. During the first 5 min after reperfusion, blood potassium measurements were conducted every one minute (T₁–T₅). The blood potassium levels at T_-10 and T₀ were 3.8 ± 0.4 and 3.9 ± 0.4 mEq/L, respectively. After reperfusion, mean increases (95% CI) in blood potassium from T_-10 and T₀ were 0.5 (0.4–0.6) and 0.4 (0.3–0.5) mEq/L, respectively. Blood potassium peaked at T₁, returned to baseline at T₃, and fell below the baseline at T₅. Peak blood potassium after reperfusion showed strong correlations with blood potassium measured at T_-10 (p < 0.001) and T₀ (p < 0.0001). These findings can support the establishment of future research plans and perioperative management of blood potassium in LDLT.

Factors Associated with Prolonged Recipient Hepatectomy Time During Liver Transplantation: A Single-Centre Experience

BACKGROUND

Recipient hepatectomy during liver transplantation can be a challenging operation and can increase cold ischaemic time. The aim of this study is to assess factors associated with prolonged recipient hepatectomy.

METHODS

From 2005 to 2015, 930 patients were submitted to liver transplantation in our hospital. Prolonged hepatectomy time was defined as operative time >180 min (from knife on skin to total hepatectomy). Patients undergoing early liver retransplantation and living donation were excluded.

RESULTS

A total of 715 patients were included in our study. Median age at transplantation was 53 (18-70) years, and median BMI was 26.2 (16-40). Median hepatectomy time was 131 min. Prolonged hepatectomy time occurred in 89 (12.4%) patients. At univariate analysis, previous decompensated cirrhosis with variceal bleeding and/or ascites, higher BMI and previous abdominal surgery were associated with prolonged operating time. Higher surgeon experience and acute liver failure were associated with shorter hepatectomy time. At multivariate analysis, previous episodes of variceal bleeding (p = 0.027, OR 1.78), BMI > 27 (p = 0.01, OR 1.75), previous abdominal surgery (p = 0.04, OR 1.68) and surgeon experience (p = 0.007, OR 2.04) were independently associated with operating time. Prolonged hepatectomy time was significantly associated with cold and total ischaemic time and intraoperative bleeding (p < 0.001, p = 0.002 and p = 0.002, respectively).

CONCLUSIONS

Recipient BMI, previous episodes of variceal bleeding, previous abdominal surgery and surgeon experience are independently associated with hepatectomy duration. These factors can be helpful to identify those patients with potentially prolonged hepatectomy time, and therefore, strategies can be put in place to optimize outcomes in this group of patients.

Protective Role of the Portocaval Shunt in Liver Transplantation

BACKGROUND

Advances in medical management and surgical technique have resulted in stepwise improvements in early post-transplant survival rates. Modifications in the surgical technique, such as the realization of the portocaval shunt (PCS), could influence survival rates. The aim of this study was to evaluate the mortality rate for 12 months after liver transplantation, analyzing the causes and risk factors related to its development and assessing the impact that PCS could have on them.

METHODS

A total of 231 recipients were included in the retrospective, longitudinal, and nonrandomized study.

RESULTS

The overall survival of the transplant was 85.2% (197 patients). The most frequent cause of death was infection (38.2%), followed by the multiorgan failure of multiple etiology (23.5%). Most of the risk factors related to mortality correspond to variables of the postoperative period. The results of the multivariate analysis identified the main risk factors for death: the presence of surgical complications and the need for renal replacement therapy. In contrast, the performance of PCS exerted a protective effect, reducing the probability of death by 70%.

CONCLUSIONS

Despite the good results obtained in several studies, there is still debate regarding the benefit of its realization. In our study, PCS was a factor associated with a reduction in mortality, with a markedly lower probability of adverse events. However, we agree with other authors on the need for larger and randomized studies to adequately determine the validity of such results.

Intraoperative Temporary Portocaval Shunt in Liver Transplant

BACKGROUND

Intraoperative temporary portocaval shunt (TPCS) has been performed during liver transplant to improve hemodynamics and renal function as well as to decrease bleeding during hepatectomy. The aim of this study was to evaluate the impact of TPCS on liver transplant in a long-term single-center study.

METHODS

From January 2006 to December 2018, all deceased donor transplants were retrospectively evaluated. Patients were divided in 2 groups: group 1, including those in whom intraoperative TPCS was performed and group 2, including those without TPCS. We analyzed recipient characteristics, survival, mortality, and complication rates in the intraoperative and postoperative periods.

RESULTS

A total of 999 deceased donor liver transplants were studied, with 509 patients in group 1 and 490 in group 2. There were 156 cases (15.61%) of preoperative portal vein thrombosis in the whole series. Postoperative renal function (P = .029) as well as length of hospital and intensive care unit stay (P = .0001) were better in group 1. Surgery time and warm ischemia time was also shorter in group 1 (P = .0001). Complications with Clavien-Dindo score ≥ 3 were higher in group 2 (P = .006). Multivariate analysis showed important risk with fulminant hepatitis (odds ratio, 2.127; 95% CI, 1.408-3.213; P < .0001) and Model for End-Stage Liver Disease > 29 (odds ratio, 2.492; 95% CI, 1.862-3.336; P < .0001). Overall survival in group 1 at 1, 5, and 10 years were 78%, 70%, and 68%, respectively. In group 2, they were 70%, 60%, and 58%, respectively (P = .027).

CONCLUSIONS

Patients who underwent intraoperative TPCS presented better postoperative renal function, less intraoperative blending, shorter surgical and warm ischemia time, shorter length of hospital and intensive care unit stay, and better overall survival after transplant. Moreover, TPCS should be used patients with severe conditions, such as fulminant hepatitis and Model for End-Stage Liver Disease score > 29.

Intraoperative Surgical Portosystemic Shunt in Liver Transplantation: Systematic Review and Meta-Analysis

Background

Expanded clinical and surgical techniques in liver transplantation can markedly improve patient and graft survival. The main purpose of this study was to evaluate the efficacy of intraoperative portocaval shunts in liver transplantation.

Material/Methods

Searches were conducted in Cochrane, MEDLINE, and EMBASE databases, and updated in January 2018. The following specific outcomes of interest were defined and evaluated separated using 2 different reviews and meta-analyses for 1) hemi-portocaval shunt (HPCS) and 2) temporary portocaval shunt (TPCS). Comparative studies were analyzed separately for both surgical portocaval shunt modalities.

Results

Only 1 well-designed randomized controlled trial was found. Most studies were retrospective or prospective. Initially, we found 1479 articles. Of those selected, 853 were from PubMed/MEDLINE, 32 were from Cochrane and 594 were from EMBASE. Our meta-analysis included a total of 3232 patients for all the included studies. Results found that 41 patients with HPCS experienced increased 1-year patient survival (OR 16.33; P=0.02) and increased 1-year graft survival (OR 17.67; P=0.01). The TPCS analysis with 1633 patients found patients had significantly shorter intensive care unit length of stay (days) (P=0.006) and hospital length of stay (P=0.02) and had decreased primary nonfunction (PNF) (OR 0.30, P=0.02) and mortality rates (OR 0.52, P=0.01).

Conclusions

Intraoperative surgical portosystemic shunt in relation to liver transplantation with TPCS was able to prevent PNF, decrease hospital length of stay and unit care length of stay. Furthermore, in analyzing data for patients with HPCS, we observed increases in the 1-year graft and patient survival rates. More prospective randomized trials are needed to arrive at a more precise conclusion.

Benefits of temporary portocaval shunt during orthotopic liver transplantation with vena cava preservation: A propensity score analysis

During orthotopic liver transplantation (OLT), clamping of the portal vein induces splanchnic venous congestion and accumulation of noxious compounds. These adverse effects could increase ischemia/reperfusion injury and subsequently the risk of graft dysfunction, especially for grafts harvested from extended criteria donors (ECDs). Temporary portocaval shunt (TPCS) could prevent these complications. Between 2002 and 2013, all OLTs performed in our center were retrospectively analyzed and a propensity score matching analysis was used to compare the effect of TPCS in 686 patients (343 in each group). Patients in the TPCS group required fewer intraoperative transfusions (median number of packed red blood cells-5 versus 6; P = 0.02; median number of fresh frozen plasma-5 versus 6; P = 0.02); had improvement of postoperative biological parameters (prothrombin time, Factor V, international normalized ratio, alkaline phosphatase, and gamma-glutamyltransferase levels); and showed significant reduction of biliary complications (4.7% versus 10.2%; P = 0.006). Survival analysis revealed that TPCS improved 3-month graft survival (94.2% versus 88.6%; P = 0.01) as well as longterm survival of elderly (ie, age > 70 years) donor grafts (P = 0.02). In conclusion, the use of TPCS should be recommended especially when considering an ECD graft. Liver Transplantation 23 174-183 2017 AASLD.

The anhepatic phase extended by temporary portocaval shunt does not affect anesthetic sensitivity and postoperative cognitive function: A case-control study

Temporary portocaval shunt (TPCS) prolongs the duration of the anhepatic phase, during which anesthetic sensitivity is highest among the 3 phases of living donor liver transplantation (LDLT). Cognitive dysfunction has been associated with increased anesthetic sensitivity and poor hepatic function. Therefore, we assessed anesthetic sensitivity to desflurane and perioperative cognitive function in patients undergoing LDLT, in whom the duration of the anhepatic phase was extended by TPCS to test the hypothesis that the prolonged anhepatic phase increases anesthetic sensitivity and causes postoperative cognitive decline.This case-control study was conducted in 67 consecutive patients undergoing LDLT from February 2014 to January 2016. Anesthesia was maintained at a 0.6 end-tidal age-adjusted minimum alveolar concentration of desflurane. The bispectral index (BIS) was maintained at less than 60 and averaged at 1-minute intervals. The mini-mental state examination (MMSE-KC) was performed 1 day before and 7 days after the LDLT. All parameters were compared between the patients undergoing TPCS (TPCS group) and the remaining patients (non-TPCS group).TPCS was performed in 16 patients (24%). TPCS prolonged the duration of the anhepatic phase (125.9 ± 29.4 vs 54.9 ± 20.5 minutes [mean ± standard deviation], P < 0.0001). The averaged BIS values during the 3 phases were comparable between the 2 groups. No significant interval changes in the averaged BIS values were observed during the 3 consecutive phases. Similarly, there were no significant differences in MMSE-KC score assessed 1 day before and 7 days after LDLT between the 2 groups. The preoperative MMSE-KC scores were unchanged postoperatively in the 2 groups.The extension of the anhepatic phase did not affect anesthetic sensitivity and postoperative cognitive function.

Benefit of early inflow exclusion during living donor liver transplantation for unresectable hepatoblastoma

BACKGROUND

Hepatoblastoma (HB) is a highly malignant primary liver tumor in children. Although liver transplantation (LT) is an effective treatment for unresectable HB with good long-term outcomes, post-transplant survival is mainly affected by recurrence, despite adjuvant chemotherapy. Novel strategies are needed to improve the outcomes in patients undergoing LT for unresectable HB.

PATIENTS AND METHODS

Twelve children received LT for unresectable HB. In 9 patients, we applied early exclusion of hepatic inflow (hepatic artery and portal vein) and creation of a temporary portocaval shunt during LT.

RESULT

There were differences in the duration of and the blood loss during operation as compared with previously reports. The estimated glomerular filtration rate was well preserved at 3, 6, and 12months and the latest follow-up after LT, and the recurrence-free survival was 88.9%.

CONCLUSION

Early inflow control during LT for unresectable HB may benefit recurrence-free survival by minimizing blood loss and tumor dissemination, preserving renal function and allowing early adjuvant chemotherapy.

Temporary intraoperative porto-caval shunt: useless or beneficial in piggy back liver transplantation?

The role of intraoperative porto-caval shunts in orthotopic liver transplantation (OLT) is controversial. Aim of this study was to analyze the effects of an intraoperative, porto-caval catheter-shunt on graft function and survival following cava sparing OLT. Four hundred and forty-eight piggy back liver transplantations with or without a temporary spontaneous porto-caval shunt between 1997 and 2010 were analyzed (shunt n = 274 vs. no shunt n = 174). Lab MELD scores and donor risk indices (DRI) were calculated. Hepatic injury (ALT, AST), -function (bilirubin, prothrombin ratio), postreperfusion liver blood flow and graft survival were registered [mean follow-up: 50.5 (0-163.0) months]. The impact of a shunt on graft survival was determined using multivariate analysis. Usage of a porto-caval shunt was associated with reduced hepatic injury (ALT, AST), whereas graft function was not affected. The shunt group showed a significantly increased portal venous blood flow after reperfusion. Retransplantation rate was decreased (7.7% vs. 20.1%, P = 0.001) and long-term graft survival was significantly increased with a porto-caval shunt (hazard ratio 2.1, P < 0.001). This effect was even more pronounced for marginal organs. Usage of intraoperative porto-caval catheter-shunts is beneficial in cava sparing OLT and is associated with reduced ischemia-reperfusion injury and improved organ survival in particular for recipients of marginal organs.

Liver transplantation in Indian Armed Forces-initial experience

BACKGROUND

This study retrospectively analyses the initial experience of liver transplantation (LT) in the Indian Armed Forces.

METHODS

Fifty-three patients underwent LT at Army Hospital (R&R) Delhi Cantt. between March 2007 and March 2011. Of these 35 patients underwent deceased donor liver transplantation (DDLT) and living donor liver transplantation (LDLT) was carried out in 18 patients. The surgical techniques, complications and mortality were analysed.

RESULTS

A high consent rate of 35.9% for organ donation was achieved by the Armed Forces Organ Retrieval and Transplantation Authority (AORTA). Biliary complications occurred in five patients (9.4%). However, most of them could be managed by endoscopic interventions. Hepatic artery thrombosis (HAT) occurred in five patients (9.4%). Of these, two DDLT grafts were revascularised following HAT, by creating extra-anatomic arterial conduits with excellent outcome. The overall mortality was 18.8% (n = 10). There was no significant difference in the overall complications or mortality in patients undergoing DDLT or LDLT.

CONCLUSION

The overall survival and morbidity in this study is comparable to those from other centres. Urgent revascularisation of grafts following HAT should be attempted as it can salvage grafts with satisfactory outcome. There is a reduction in the incidence of biliary complications with refinements in surgical techniques.

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.

Comparison of surgical methods in liver transplantation: retrohepatic caval resection with venovenous bypass (VVB) versus piggyback (PB) with VVB versus PB without VVB

Use of piggyback technique (PB) and elimination of venovenous bypass (VVB) have been advocated in adult liver transplantation (LT). However, individual contribution of these two modifications on clinical outcomes has not been fully investigated. We performed a retrospective review of 426 LTs within a 3-year period, when three different surgical techniques were employed per the surgeons' preference: retrohepatic caval resection with VVB (RCR+VVB) in 104 patients, PB with VVB (PB+VVB) in 148, and PB without VVB (PB-Only) in 174. The primary outcomes were intraoperative blood transfusion and the patient and graft survivals. Demographic profiles were similar, except younger recipient age in RCR+VVB and fewer number of grafts with cold ischemic time over 16 h in PB-Only. PB-Only required lesser intraoperative red blood cells (P=0.006), fresh frozen plasma (P=0.005), and cell saver return (P=0.007); had less incidence of acute renal failure (P=0.001), better patient survival (P=0.039), and graft survival (P=0.003). The benefits of PB+VVB were only found in shortened total surgical time (P=0.0001) and warm ischemic time (P=0.0001), and less incidence of acute renal failure (P=0.001) than RCR+VVB. PB-Only method seemed to provide the best clinical outcome. The benefit of PB was not fully achieved when it was used with VVB.