Blood products and liver transplantation: A strategy to balance optimal preparation with effective blood stewardship.

BACKGROUND: Unanticipated transfusion requirements during liver transplantation can delay lifesaving intraoperative resuscitation and strain blood bank resources. Risk-stratified preoperative blood preparation can mitigate these deleterious outcomes. STUDY DESIGN AND METHODS: A two-tiered blood preparation protocol for liver transplantation was retrospectively evaluated. Eleven binary variables served as criteria for high-risk (HR) allocation. Primary outcomes included red blood cell (RBC), plasma (FFP), and platelet (Plt) utilization. Secondary outcomes included product under- and overpreparation. Contingency tables for transfusion requirements above the population means were generated using 15 clinical variables. Modified protocols were developed and retrospectively optimized using the study population. RESULTS: Of 225 recipients, 102 received HR preoperative orders, which correlated to higher intraoperative transfusion requirements. However, univariate analysis identified only two statistical risk factors per product: Hgb ≤7.8 g/dl (p < .001) and MELD ≥38 (p = .035) for RBCs, Hgb ≤7.8 g/dl (p = .002) and acute alcoholic hepatitis (p = 0.015) for FFP, and Hgb ≤7.8 g/dl (p = .001) and normothermic liver preservation (p = .037) for Plts. Based on these findings, we developed modified protocols for individual products, which were evaluated retrospectively for their effectiveness at reducing under-preparatory events while limiting product overpreparation. Cohort statistics were used to define the preparation strategy for each protocol. Retrospective comparative analysis demonstrated the superiority of the modified protocols by improving the under-preparation rate from 24% to <10% for each product, which required a 1.56-fold and 1.44-fold increase in RBC and FFP overpreparation, respectively. Importantly, there was no difference in Plt overpreparation. DISCUSSION: We report translatable data-driven blood bank preparation protocols for liver transplantation.

Long-term Outcomes and Survival in Moderate-severe Portopulmonary Hypertension After Liver Transplant.

BACKGROUND: Portopulmonary hypertension is present in an estimated 5.3% to 8.5% of liver transplant candidates. Untreated, 5-year survival is estimated between 14% and 28%. Moderate-severe disease is a contraindication to liver transplant due to the high perioperative mortality, but patients optimized with pulmonary vasodilator therapy can become eligible for transplant. There is minimal data regarding posttransplant outcomes and ability to discontinue pulmonary vasodilator therapy posttransplant. METHODS: We performed a single-center retrospective analysis to evaluate long-term outcomes of patients with moderate-severe portopulmonary hypertension who were optimized with pulmonary vasodilator therapy, became eligible for liver transplant, and subsequently underwent transplant. We identified 24 patients optimized with pulmonary vasodilator therapy who underwent subsequent liver transplantation and 25 patients who were treated with pulmonary vasodilator therapy alone. RESULTS: In the transplanted cohort, 1-year survival from portopulmonary hypertension diagnosis date: 95.8%, 3-year survival: 90.9%, and 5-year survival: 90.9%. Posttransplant; 1-, 3-, and 5-year survival was 86.9%. Among transplanted patients, 41.6% (10/24) were optimized with nonparenteral therapy. Following transplantation, 100% (14/14) of the surviving patients were able to discontinue parenteral therapy; median time: 7.2 months (interquartile range: 5.1-8.9 mo), while 61.9% (13/21) were able to discontinue pulmonary vasodilator therapy altogether; median time: 13.9 months (interquartile range: 5.1-17.6 mo). CONCLUSIONS: Patients who are optimized with pulmonary vasodilator therapy before liver transplant can have excellent long-term outcomes posttransplant. Oral pulmonary vasodilator therapy can be effective treatment to qualify a patient for transplant, and the majority are able to wean from pulmonary vasodilator therapy entirely posttransplant.

Risk Factors for Intracardiac Thrombus During Liver Transplantation.

Intracardiac thrombus (ICT) is an intraoperative complication with high mortality that occurs during orthotopic liver transplantation (OLT). Patients with end-stage liver disease have compromised coagulation pathways, and when combined with stressors of surgery, thrombi can form. However, it is unknown which patients are most likely to develop ICT. We performed a retrospective cohort study of all OLT patients at our hospital from 2010 to 2017 to identify risk factors for ICT. An analysis was performed with conventional bivariate tests and logistic regression. The incidence of ICT during OLT was 4.2% (22/528) with a 45.5% (10/22) mortality. Patients who developed ICT had higher physiologic Model for End-Stage Liver Disease scores at the time of transplant (25.1 versus 32.4; P = 0.004), received grafts from donors with a higher body mass index (28.1 versus 32.2 kg/m2 ; P = 0.007), and had longer intraoperative warm ischemia times (53.1 versus 67.5 minutes; P = 0.001). The odds of developing ICT were significantly lower after administration of intravenous (IV) heparin prior to inferior vena cava (IVC) clamping compared with no administration of heparin (odds ratio, 0.25; 95% confidence interval, 0.08-0.75; P = 0.01). In conclusion, the incidence of ICT at our institution is higher than previously reported, which may be explained by our routine use of transesophageal echocardiography. Although many factors associated with ICT in this study are nonmodifiable, administration of IV heparin prior to IVC cross-clamping is modifiable and was found to be protective. Further studies will be needed to confirm findings and ultimately aid in preventing these lethal events.

Significant Hyperfibrinolysis in a Patient With Intracardiac Thrombosis: To Give Antifibrinolytics or Not?

The hemostatic system is a delicate balance between the coagulation, anticoagulation, and fibrinolytic systems and is responsible for preventing both hemorrhage and thrombosis. End stage liver disease is characterized by a rebalanced hemostatic system that is fragile and easily tipped towards either hemorrhage or thrombosis. During an orthotopic liver transplantation, patients are exposed to a wide variety of factors that can shift them from a hypercoagulable state to a hypocoagulable state almost instantaneously. The treatment for these two disease states contradict each other, and therefore patients in this condition can be extremely difficult to manage. Here, we present a patient who underwent an orthotopic liver transplantation and suffered an intracardiac thrombosis shortly after reperfusion of the donor graft, that resolved with supportive care, who then went on to develop severe persistent hyperfibrinolysis and massive hemorrhage that was successfully treated with an antifibrinolytic agent.

A Misguided Contraindication: International Normalized Ratio in Acute Liver Failure Precluding Thrombolysis for Massive Pulmonary Embolism: A Case Report.

Massive pulmonary embolism and its treatment with thrombolysis both carry grave risks. Optimal management hinges on determining the risk-to-benefit ratio of thrombolytic administration. For patients with liver dysfunction, assessing bleeding risk is challenging because they may have elevations in the international normalized ratio yet be hypercoagulable. We describe a patient with massive pulmonary embolism and new-onset liver failure, who-absent contraindications-warranted thrombolysis. Initial laboratory values, however, revealed an elevated international normalized ratio, which precluded lysis, despite a hypercoagulable Thromboelastogram. We believe that viscoelastic testing of coagulation is essential for evaluating coagulation in liver dysfunction, particularly when considering thrombolysis.

Multidisciplinary approach to cardiac and pulmonary vascular disease risk assessment in liver transplantation: An evaluation of the evidence and consensus recommendations.

Liver transplant (LT) candidates today are older, have greater medical severity of illness, and have more cardiovascular comorbidities than ever before. In addition, there are specific cardiovascular responses in cirrhosis that can be detrimental to the LT candidate. Cirrhotic cardiomyopathy, a condition characterized by increased cardiac output and a reduced ventricular response to stress, is present in up to 30% of patients with cirrhosis, thus challenging perioperative management. Current noninvasive tests that assess for subclinical coronary and myocardial disease have low sensitivity, and altered hemodynamics during the LT surgery can unmask latent cardiovascular disease either intraoperatively or in the immediate postoperative period. Therefore, this review, assembled by a group of multidisciplinary experts in the field and endorsed by the American Society of Transplantation Liver and Intestine and Thoracic and Critical Care Communities of Practice, provides a critical assessment of the diagnosis of cardiac and pulmonary vascular disease and interventions aimed at managing these conditions in LT candidates. Key points and practice-based recommendations for the diagnosis and management of cardiac and pulmonary vascular disease in this population are provided to offer guidance for clinicians and identify gaps in knowledge for future investigations.