Insertion and management of percutaneous veno-venous bypass cannula for liver transplantation: a reference for transplant anesthesiologists

Venovenous bypass in liver transplantation: Exploring the benefits, efficacy, and safety

Venovenous bypass (VVB) is a technique used in liver transplantation (LT) to maintain hemodynamic stability and abdominal organ perfusion and thereby improve patient outcomes. Despite its perceived benefits, VVB utilization has declined globally due to concerns related to heparinization, major bleeding and the need for expertise. Recent advancements, such as percutaneous cannulation techniques and improved extracorporeal technology have improved the safety of VVB in LT. This paper presents a modified VVB circuit with enhanced safety features. Cannulation plays a pivotal role in VVB establishment, with percutaneous methods increasingly favored. Studies demonstrate VVB's efficacy in improving patient outcomes with lower incidence of acute kidney injury and reduced operative time and blood loss, with no added morbidity or mortality. However, its routine use faces challenges, with alternative techniques gaining traction. Our experience highlights VVB's role in various clinical scenarios, including patients with high Model for End-Stage Liver Disease (MELD) scores, challenging surgical anatomy, portal vein thrombosis and pre-existing cardiovascular disease, emphasizing its safety and efficacy. Continued research is needed to optimize VVB techniques and ensure better outcomes for liver transplant recipients.

Venovenous bypass in adult liver transplant recipients: A single-center observational case series

BACKGROUND

Very little information is currently available on the use and outcomes of venovenous bypass (VVB) in liver transplantation (LT) in adults in Australia. In this study, we explored the indications, intraoperative course, and postoperative outcomes of patients who underwent VVB in a high-volume LT unit.

METHODS

The study was a single-center, retrospective observational case series of adult patients who underwent VVB during LT at Austin Health in Melbourne, Australia between March 2008 and March 2022. Information on baseline preoperative status and intraoperative variables, including specific VVB characteristics as well as postoperative and VVB-related complications was collected. The lengths of intensive care unit and hospital stays as well as intraoperative and in-hospital mortality were recorded.

RESULTS

Of the 900 LTs performed at this center during the aforementioned 14-year period, 27 (3%) included a VVB procedure. VVB was performed electively in 16 of these 27 patients (59.3%) and as a rescue technique to control massive bleeding in the other 11 (40.1%). The median (interquartile range [IQR]) age of those who underwent VVB procedures was 48 (39-55) years; the median age was 56 (47-62) years in the non-VVB group (p<0.0001). The median model for end-stage liver disease (MELD) scores were similar between the two patient groups. Complete blood data was available for 622 non-VVB patients. Twenty-six VVB (96.3%) and 603 non-VVB (96.9%) patients required intraoperative blood transfusions. The median (IQR) number of units of packed red blood cells transfused was 7 (4.8-12.5) units in the VVB group compared to 3.0 units (1.0-6.0) in the non-VVB group (p<0.0001). Inpatient mortality was 18.5% and 1.1% for the VVB and non-VVB groups, respectively (p<0.0001). There were no significant differences in length of hospital stay or incidence of acute kidney injury, primary graft dysfunction, or long-term graft failure between the two groups. Patients in the VVB group experienced a higher rate of postoperative non-anastomotic biliary stricture compared to patients in the non-VVB group (33% and 7.9%, respectively; p = 0.0003).

CONCLUSIONS

VVB continues to play a vital role in LT. This case series highlights the heightened risk of major complications linked to VVB. However, the global transition to selective use of VVB underscores the urgent need for collaborative multi-center studies designed to address outstanding questions and parameters related to the safe implementation of this procedure.

Use of Transesophageal Echocardiography During Orthotopic Liver Transplantation: Simplifying the Procedure

The intraoperative management of patients undergoing orthotopic liver transplantation (OLT) is influenced by the cardiovascular manifestations typically found in the context of end-stage liver disease, by the presence of concomitant cardiovascular disease, and by the significant hemodynamic changes that occur during surgery. Hypotension and intraoperative blood pressure fluctuations during OLT are associated with liver graft dysfunction, acute kidney failure, and increased risk of 30-d mortality. Patients also frequently present hemodynamic instability due to various causes, including cardiac arrest. Recent evidence has shown transesophageal echocardiography (TEE) to be a useful minimally invasive monitoring tool in patients undergoing OLT that gives valuable real-time information on biventricular function and volume status and can help to detect OLT-specific complications or situations. TEE also facilitates rapid diagnosis of life-threatening conditions in each stage of OLT, which is difficult to identify with other types of monitoring commonly used. Although there is no consensus on the best approach to intraoperative monitoring in these patients, intraoperative TEE is safe and useful and should be recommended during OLT, according to experts, for assessing hemodynamic changes, identifying possible complications, and guiding treatment with fluids and inotropes to achieve optimal patient care.

Using Transesophageal Echocardiography in Liver Transplantation with Veno-Venous Bypass Is a Tool with Many Applications: A Case Series from an Italian Transplant Center

BACKGROUND

Hemodynamic instability (HDI) is common during liver transplantation (LT); veno-venous bypass (VVB) is a tool used in selected cases to ensure hemodynamic stability and for surgical needs. Transesophageal echocardiography (TEE) allows the transplant team to identify the causes of HDI and to guide therapies. We present a case series of four patients showing the valuable role of TEE during LT in VVB.

METHODS

We report four explicative cases of TEE use in LT with VVB performed at IRCCS Azienda Ospedaliero-Universitaria di Bologna. Four transplants were performed between 2016 and 2022.

RESULTS

Many authors have highlighted the diagnostic value of TEE during LT in the case of HDI. However, its specific role during LT with VVB is poorly described. This paper illustrates multiple potential uses of TEE in LT with VVB: TEE as a guide for catheterization and optimal cannula positioning, TEE as a tool for intraoperative Patent Foramen Ovale management, TEE as help for anticoagulation therapy and finally, TEE as support when evaluating bypass efficiency and correcting hypovolemia.

CONCLUSION

TEE is a useful instrument during LT with VVB. However, further studies are needed to assess the suitable applications of TEE during LT in patients with HDI requiring VVB. TEE should be part of the anesthetist's cultural background.

Perioperative management of adult living donor liver transplantation: Part 1 - recipients

Living donor liver transplantation was first developed to mitigate the limited access to deceased donor organs in Asia in the 1990s. This alternative liver transplantation option has become an established and widely practiced transplantation method for adult patients suffering from end-stage liver disease. It has successfully addressed the shortage of deceased donors. The Society for the Advancement of Transplant Anesthesia and the Korean Society of Transplant Anesthesia jointly reviewed published studies on the perioperative management of live donor liver transplant recipients. The review aims to offer transplant anesthesiologists and critical care physicians a comprehensive overview of the perioperative management of adult live liver transplantation recipients. We feature the status, outcomes, surgical procedure, portal venous decompression, anesthetic management, prevention of acute kidney injury, avoidance of blood transfusion, monitoring and therapeutic strategies of hemodynamic derangements, and Enhanced Recovery After Surgery protocols for liver transplant recipients. This article is protected by copyright. All rights reserved.

Vitamin D levels in liver transplantation recipients and early postoperative outcomes: Prospective observational DLiverX study

BACKGROUND & AIMS

In critically ill patients with liver disease, vitamin D deficiency is associated with higher disease severity, increased frequency of infections, and worse outcomes. This study sought to describe the trend of vitamin D in orthotopic liver transplantation (OLT) recipients and its association with outcomes.

METHODS

Prospective observational study of 67 consecutive OLT recipients enrolled between September, 2016 and August, 2017 at IRCCS-ISMETT, Palermo (Italy). Trend of vitamin D levels and potential factors influencing it levels were evaluated through a generalized linear mixed regression model.

RESULTS

Sixty-four (95.5%) recipients were vitamin D deficient (<20 ng/ml), with a median value of 8.8 ng/ml [6.2-12.9], and forty-seven of these (70.1%) showed severe deficiency (<12 ng/ml) at baseline, 7.9 ng/ml [5.4-8.9]. The baseline vitamin D showed an inverse correlation with liver disease severity: Child-Pugh, MELD score, bilirubin, INR, and organ failure (p < 0.01) at baseline. Vitamin D increased on postoperative day (POD) 28 compared with POD1: +4.5 ng/ml, C.I. 95% 3.6-5.3 ng/ml, p < 0.01. Lower baseline vitamin D, donor age, transfusion of fresh frozen plasma (negative impact, all p < 0.05), and intra-operative bypass (positive impact at POD 28, p < 0.01) were associated with variation of vitamin D levels after transplantation. Incomplete graft recovery was associated with lower vitamin D on POD28: 8.2 ± 4.4 versus 13.8 ± 9.4 ng/ml, p < 0.01; the odds ratio (OR) was 0.84; CI 95% 0.73-0.97, p = 0.014. The OR for infections within POD 28 was inversely associated with baseline vitamin D: 0.87; CI 95% 0.79-0.98, p = 0.02, and with vitamin D level at baseline <12 ng/ml: OR 6.44; CI 95% 1.66-24.94; p < 0.01.

CONCLUSIONS

Preoperative Vitamin D is correlated with disease severity, and was highly associated with invasive infection in the first 28 PODs. After OLT, the value on POD 28 had a strong association with graft function.

Critical Importance of Low-Dose Tissue Plasminogen Activator Policy for Treating Intraoperative Pulmonary Thromboembolism During Liver Transplantation

Tissue plasminogen activator (tPA) has been reported to treat intraoperative pulmonary thromboembolism (PTE) during liver transplantation (LT). However, tPA administration is often delayed due to fear of uncontrolled bleeding and storage in a refrigerator outside of operating rooms. Various dosages of tPA were used. We hypothesize that a policy of tPA storage and low dosage use improves patient outcomes. At a transplantation center, a multidisciplinary committee has implemented a tPA policy since April 2014, which includes the following: (1) timely administering of low-dose tPA (0.5-4 mg) for intraoperative PTE; (2) keeping 2 vials of tPA (2 mg/vial) in the operating room at room temperature; and (3) transferring unused tPA vials to the cardiology catheterization laboratory for next-day use. A prospective observational study was conducted to record the incidence and outcome of PTE during LTs. Over the next 19 months, 99 adult deceased donor LTs were performed with 1 (1.0%) intraoperative PTE. A 45-year-old woman with hepatitis C developed PTE within 5 minutes after graft reperfusion. A 2-mg tPA was immediately administered via a central venous line with hemodynamic improvement and clot lysis. Thromboelastography was normalized in 90 minutes. Five LT cases developing intraoperative PTE have been reported to receive “standard” dosages of tPA (20-110 mg) or urokinase (4400 IU/kg), which were administered more than 20 minutes after the diagnosis of PTE. One intraoperative death and one later mortality were noted with intracranial hemorrhages/infarction of 3 cases. The multidisciplinary low-dose tPA policy for PTE was suggested to be effective.

In Situ Hypothermic Perfusion of the Liver for Complex Hepatic Resection: Surgical Refinements

INTRODUCTION

While total vascular exclusion (TVE) with veno-venous bypass and hypothermia may be undertaken to increase liver tolerance for complex liver resection, these procedures are still associated with elevated rates of postoperative complications and mortality. In particular, one of the main issues of this strategy is the management of bleeding after declamping, which is enhanced by both hypothermic state and acidosis. To overcome this high risk of morbidity, several technical refinements might be undertaken and here described (with video).

METHODS

All patients, requiring TVE >60 min and liver cooling during hepatectomy, were retrospectively included in this study. Technical key points as (a) patient selection, (b) anesthetic management, (c) two-surgeon's technique, (d) preparation for clamping, (e) veno-venous bypass, (f) cooling of the liver, and (g) parenchymal transection, rewarming, and declamping are described and detailed.

RESULTS

From 2011 to 2013, we included 8 cases of liver resection with TVE, veno-venous bypass, and hypothermia for malignant disease. Due to the technical refinements, median observed overall blood loss of 550 ml (300-900) including 200 ml (50-300) at declamping and transfusion of packed red blood cell (PRBC) units was required in 5 patients with a mean of 1.25 PRBC/patient.

CONCLUSION

The association of TVE, veno-venous bypass, and liver cooling can reduce the time of transection, and blue dye injection and liver rewarming before declamping can reduce blood loss and coagulopathy. Altogether, limited blood loss can be achieved for these complex procedures and may allow to decreasing morbidity.

Assessment of thrombosis in right internal jugular vein after percutaneous superior vena cava catheter insertion during cardiovascular surgery with cardiopulmonary bypass

OBJECTIVE

We evaluated the incidence of percutaneous superior vena cava catheter-related thrombosis and identified risk factors for developing the condition in patients undergoing cardiovascular surgery with cardiopulmonary bypass.

METHODS

A total of 121 patients were evaluated. A percutaneous superior vena cava catheter was inserted into the right internal jugular vein during cardiovascular surgery with cardiopulmonary bypass. The right internal jugular vein was evaluated using ultrasonography, including cross-sectional area and velocity just before insertion of the percutaneous superior vena cava catheter (preoperative) and 24 hours and 48 hours after its insertion. If an echogenic mass was detected in the right internal jugular vein, the size was measured.

RESULTS

The incidence of thrombosis in the right internal jugular vein was 56.2%. Change in the right internal jugular vein cross-sectional area and velocity had no clinical implications. Multiple logistic regression analysis identified age (odds ratio, 1.061; 95% confidence interval, 1.022-1.101; P = .002), superior vena cava catheter indwelling duration (odds ratio, 1.015; 95% confidence interval, 1.008-1.023; P < .001), and amount of transfusion platelet concentrate (odds ratio, 1.155; 95% confidence interval, 1.030-1.295; P = .013) as risk factors for percutaneous superior vena cava catheter-related thrombosis in the right internal jugular vein.

CONCLUSIONS

The incidence of percutaneous superior vena cava catheter-related thrombosis was higher than conventional central venous catheter-related thrombosis. Risk factors were age, superior vena cava catheter indwelling duration, and amount of transfusion platelet concentrate.

Isolated hepatic perfusion as a treatment for liver metastases of uveal melanoma

Isolated hepatic perfusion (IHP) is a procedure where the liver is surgically isolated and perfused with a high concentration of the chemotherapeutic agent melphalan. Briefly, the procedure starts with the setup of a percutaneous veno-venous bypass from the femoral vein to the external jugular vein. Via a laparotomy, catheters are then inserted into the proper hepatic artery and the caval vein. The portal vein and the caval vein, both supra- and infrahepatically, are then clamped. The arterial and venous catheters are connected to a heart lung machine and the liver is perfused with melphalan (1 mg/kg body weight) for 60 min. This way it is possible to locally perfuse the liver with a high dose of a chemotherapeutic agent, without leakage to the systemic circulation. In previous studies including patients with isolated liver metastases of uveal melanoma, an overall response rate of 33-100% and a median survival between 9 and 13 months, have been reported. The aim of this protocol is to give a clear description of how to perform the procedure and to discuss IHP as a treatment option for liver metastases of uveal melanoma.

Clinical applicability of rapid thrombelastography and functional fibrinogen thrombelastography to adult liver transplantation

Unlike kaolin thrombelastography (k-TEG), the clinical utility of rapid thrombelastography (r-TEG) and functional fibrinogen thrombelastography (FF-TEG) has not been tested in liver transplantation (LT). These thrombelastography techniques were simultaneously performed at the time of the skin incision (the baseline) and 30 minutes after graft reperfusion (III + 30) for 27 consecutive adult LT patients. k-TEG and r-TEG parameters [alpha angle (α) and maximum amplitude of the clot (MA)] were compared in addition to the assay time. Estimated FF-TEG fibrinogen levels were compared with plasma fibrinogen measurements. At the baseline, the values of Spearman's correlation coefficient (r) between k-TEG and r-TEG were moderate for α (r = 0.40, P = 0.06) and strong for MA (r = 0.90, P < 0.01). At III + 30, r was 0.46 (P < 0.05) for α and 0.80 (P < 0.01) for MA. The average time required to measure MA via r-TEG was decreased in comparison with k-TEG [from 29.7 to 21.6 minutes at the baseline (a 22% reduction) and from 29.6 to 22.9 minutes at III + 30 (a 23% reduction)]. FF-TEG correlated strongly with the plasma fibrinogen level at the baseline (r = 0.90, P < 0.01); however, FF-TEG overestimated the fibrinogen level at III + 30 (r = 0.58, P = 0.01). In conclusion, in adult LT, r-TEG correlates with k-TEG strongly for MA but only moderately for α. FF-TEG estimates the plasma fibrinogen level well at the baseline; however, it must be interpreted with caution because of its overestimation after graft reperfusion when the plasma fibrinogen level often decreases to less than 100 mg/dL.

Cardiac arrest during adult liver transplantation: a single institution's experience with 1238 deceased donor transplants

Liver transplantation (LT) is one of the highest risk noncardiac surgeries. We reviewed the incidence, etiologies, and outcomes of intraoperative cardiac arrest (ICA) during LT. Adult cadaveric LT recipients from January 1, 2001 through December 31, 2009 were reviewed. ICA was defined as an event requiring either closed chest compression or open cardiac massage. Cardiac arrest patients who recovered with only pharmacological interventions were excluded. Data included etiologies and outcomes of ICA, intraoperative deaths (IDs) and hospital deaths (HDs), and potential ICA risk factors. ICA occurred in 68 of 1238 LT recipients (5.5%). It occurred most frequently during the neohepatic phase (60 cases or 90%), and 39 of these cases (65.0%) experienced ICA within 5 minutes after graft reperfusion. The causes of ICA included postreperfusion syndrome (PRS; 26 cases or 38.2%) and pulmonary thromboembolism (PTE; 24 cases or 35.3%). A higher Model for End-Stage Liver Disease (MELD) score was found to be the most significant risk factor for ICA. The ID rate after ICA was 29.4% (20 cases), and the HD rate was 50.0% (34 cases). The 30-day patient survival rate after ICA was 55.9%, and the 1-year survival rate was 45.6%: these rates were significantly lower (P < 0.001) than those for non-ICA patients (97.4% and 85.1%, respectively). In conclusion, the incidence of ICA in adult cadaveric LT was 5.5% with an intraoperative mortality rate of 29.4%. ICA most frequently occurred within 5 minutes after reperfusion and resulted mainly from PRS and PTE. A higher MELD score was identified as a risk factor.

Complications related to invasive hemodynamic monitors during adult liver transplantation

The rate of complications directly related to invasive monitors during liver transplantation (LT) was reviewed in 1206 consecutive adult LTs performed over 8.6 yr (1/1/2004-7/31/2012). The designated anesthesiologists placed intra-operative monitors, including two arterial catheters (via the radial and the right femoral arteries), central venous catheters (a 9 Fr. catheter and an 18 Fr. veno-venous bypass [VVB] return cannula in an internal jugular vein), a pulmonary artery catheter, and a transesophageal echocardiography (TEE) probe. A 17 Fr. VVB drainage cannula was placed via the left femoral vein. No Clavien-Dindo Grade V (death) or Grade IV (organ dysfunction) complication was identified. Nine Grade III complications (requiring surgical intervention) and 15 Grade II complications (conservative treatment) were noted. Seven (0.58% in 1206 cases) were related to a femoral arterial line with Grade III of four; seven (0.58%) were due to VVB return cannula in the femoral vein with Grade III of one; four (0.33%) were related to central venous catheters with Grade III of two; four (0.33%) were due to a TEE probe with Grade III of two; and two minor complications (0.17%) that were related to a radial arterial line. No complication was observed with a pulmonary arterial catheter. Current invasive monitors placed during LT have an acceptable risk.

Pulmonary thromboembolism during adult liver transplantation: incidence, clinical presentation, outcome, risk factors, and diagnostic predictors

BACKGROUND

Intraoperative pulmonary thromboembolism (PTE) is an often overlooked cause of mortality during adult liver transplantation (LT) with diagnostic challenge. The goals of this study were to investigate the incidence, clinical presentation, and outcome of PTE and to identify risk factors or diagnostic predictors for PTE.

METHODS

Four hundred and ninety-five consecutive, isolated, deceased donor LTs performed in an institution for a 3 yr period (2004-6) were analysed. The standard technique was a piggyback method with veno-venous bypass without prophylactic anti-fibrinolytics. The clinical diagnosis of PTE was made with (i) acute cor pulmonale, and (ii) identification of blood clots in the pulmonary artery or observation of acute right heart pressure overload with or without intracardiac clots with transoesophageal echocardiography.

RESULTS

The incidence of PTE was 4.0% (20 cases); cardiac arrest preceded the diagnosis of PTE [75% (15)] and PTE occurred during the neo-hepatic phase [85% (17)], especially within 30 min after graft reperfusion [70% (14)]. Operative and 60 day mortalities of patients with PTE were higher (P<0.001) than those without PTE (30% vs 0.8% and 45% vs 6.5%). Comparison of perioperative data between the PTE group (n=20) and the non-PTE group (n=475) revealed cardiac arrest and flat-line thromboelastography in three channels (natural, amicar, and protamine) at 5 min after graft reperfusion as the most significant risk factors or diagnostic predictors for PTE with an odds ratio of 154.32 [95% confidence interval (CI): 44.82-531.4] and 49.44 (CI: 15.6-156.57), respectively.

CONCLUSIONS

These findings confirmed clinical significance of PTE during adult LT and suggested the possibility of predicting this devastating complication.

Operative risks of domino liver transplantation for the familial amyloid polyneuropathy liver donor and recipient: a double analysis

Although domino liver transplantation (LT) is an established procedure, data about the operative risks are limited. This study aimed at evaluating the operative risks of domino LT. Two retrospective analyses were conducted (comparison of familial amyloid polyneuropathy [FAP] liver donors [61 patients] vs. FAP nondonors [39 patients] and FAP liver recipients [61 patients] vs. deceased donor liver recipients [61 patients]). First analysis showed a 60-day mortality of 6.6% for FAP donors and 7.7% for FAP nondonors (p = 1.0). No patient developed primary graft nonfunction. Acute rejection was higher in FAP nondonors compared to FAP donors (38.5% vs. 13.1%). Both groups had similar vascular and biliary complication rates. ICU stay was similar, whereas total hospitalization was longer for FAP nondonors. Both groups had similar 1- and 5-year patient and graft survival rates (83.4% vs. 87.2%, and 79.8% vs. 71.8%, p = 0.7) and (83.3% vs. 87.2%, and 79.1% vs.71.8%, p = 0.7). The second analysis showed a 1.6% mortality for FAP liver recipients vs. 3.2% of the control group (p = 1). Both groups had similar morbidity and technical complication rates (18.0% vs. 13.1%, p = 0.45) and (0.18 vs. 0.15, p = 0.65). The domino procedure does not add any risk to FAP donor or recipient. It increases the organ pool allowing transplantation of marginal recipients who otherwise are denied deceased donor liver transplantation.

Portopulmonary hypertension as an indication for combined heart, lung, and liver or lung and liver transplantation: literature review and case presentation

End-stage liver disease with severe portopulmonary hypertension (PPHTN), which is refractory to vasodilator therapies, is a contraindication for isolated liver transplantation (LT) because of the high mortality rate. Combined heart, lung, and liver transplantation (CHLLT) and combined lung and liver transplantation (CLLT) can be lifesaving options for these patients; however, these procedures have rarely been performed. A 52-year-old man had end-stage liver disease due to hepatitis C and PPHTN; the latter showed a suboptimal response to pulmonary vasodilator therapy with continuous intravenous treprostinil sodium and oral sildenafil citrate and was considered a contraindication to isolated LT. His preoperative left ventricular function was normal, and he had mild to moderate right ventricular dysfunction. He underwent CLLT, which consisted of sequential double-lung transplantation under cardiopulmonary bypass followed by standard LT under venovenous bypass. Re-exploration of the chest cavity was necessary because of bleeding, and respiratory failure developed; however, the patient recovered, was discharged home on day 26, and remained well 1 year after CLLT with the standard immunosuppressants (similar to those used for heart and lung transplantation). For PPHTN, combined thoracic organ and liver transplantation has been reported in only 10 patients. Six of these patients, including our case, underwent CLLT, whereas 4 patients underwent CHLLT. Notably, 2 of the 6 CLLT patients expired within 24 hours of transplantation because of acute right heart failure. CHLLT should be considered for patients with refractory PPHTN. The assessment of preoperative cardiac function is a vital part of the decision to include heart transplantation in CLLT.