Ramona Nicolau-Raducu

Diagnosis and treatment of intracardiac thrombosis during orthotopic liver transplantation

Intracardiac thrombus formation during orthotopic liver transplantation can be a catastrophic event leading to death. Most often this devastating complication occurs after reperfusion and may be related to massive blood transfusion, marginal liver grafts, tendencies towards hypercoagulability, or the potential role of antifibrinolytics. We report a case of an intracardiac thrombus occurring during the hepatectomy stage (stage I) of orthotopic liver transplantation. Transesophageal echocardiography was used to quickly diagnose the thrombus, allowing rapid pharmacological intervention and later guide surgical evacuation of the intracardiac thrombus via the inferior vena cava.

Adverse cardiac events after orthotopic liver transplantation: A cross‐sectional study in 389 consecutive patients

Current American College of Cardiology/American Heart Association guidelines caution that preoperative noninvasive cardiac tests may have poor predictive value for detecting coronary artery disease in liver transplant candidates. The purpose of our study was to evaluate the role of clinical predictor variables for early and late cardiac morbidity and mortality and the predictive values of noninvasive cardiac tests for perioperative cardiac events in a high‐risk liver transplant population. In all, 389 adult recipients were retrospectively analyzed for a median follow‐up time of 3.4 years (range = 2.3‐4.4 years). Overall survival was 83%. During the first year after transplantation, cardiovascular morbidity and mortality rates were 15.2% and 2.8%. In patients who survived the first year, cardiovascular morbidity and mortality rates were 3.9% and 2%, with cardiovascular etiology as the third leading cause of death. Dobutamine stress echocardiography (DSE) and single‐photon emission computed tomography had respective sensitivities of 9% and 57%, specificities of 98% and 75%, positive predictive values of 33% and 28%, and negative predictive values of 89% and 91% for predicting early cardiac events. A rate blood pressure product less than 12,000 with DSE was associated with an increased risk for postoperative atrial fibrillation. Correspondence analysis identified a statistical association between nonalcoholic steatohepatitis/cryptogenic cirrhosis and postoperative myocardial ischemia. Logistic regression identified 3 risk factors for postoperative acute coronary syndrome: age, history of coronary artery disease, and pretransplant requirement for vasopressors. Multivariable analysis showed statistical associations of the Model for End‐Stage Liver Disease score and the development of acute kidney injury as risk factors for overall cardiac‐related mortality. These findings may help in identifying high‐risk patients and may lead to the development of better cardiac tests. Liver Transpl 21:13‐21, 2015.

Safety and Outcomes in 100 Consecutive Donation After Circulatory Death Liver Transplants Using a Protocol That Includes Thrombolytic Therapy

Donation after circulatory death (DCD) liver transplantation (LT) reportedly yields inferior survival and increased complication rates compared with donation after brain death (DBD). We compare 100 consecutive DCD LT using a protocol that includes thrombolytic therapy (late DCD group) to an historical DCD group (early DCD group n = 38) and a cohort of DBD LT recipients (DBD group n = 435). Late DCD LT recipients had better 1‐ and 3‐year graft survival rates than early DCD LT recipients (92% vs. 76.3%, p = 0.03 and 91.4% vs. 73.7%, p = 0.01). Late DCD graft survival rates were comparable to those of the DBD group (92% vs. 93.3%, p = 0.24 and 91.4% vs. 88.2%, p = 0.62). Re‐transplantation occurred in 18.4% versus 1% for the early and late DCD groups, respectively (p = 0.001). Patient survival was similar in all three groups. Ischemic‐type biliary lesions (ITBL) occurred in 5%, 3%, and 0.2% for early DCD, late DCD, and DBD groups, respectively, but unlike in the early DCD group, in the late DCD group ITBL was endoscopically managed and resolved in each case. Using a protocol that includes a thrombolytic therapy, DCD LT yielded patient and graft survival rates comparable to DBD LT.

Epsilon-Aminocaproic Acid Has No Association With Thromboembolic Complications, Renal Failure, or Mortality After Liver Transplantation.

OBJECTIVES To examine the role of epsilon-aminocaproic acid (EACA) administered after reperfusion of the donor liver in the incidences of thromboembolic events and acute kidney injury within 30 days after orthotopic liver transplantation. One-year survival rates between the EACA-treated and EACA-nontreated groups also were examined. DESIGN Retrospective, observational, cohort study design. SETTING Single-center, university hospital. PARTICIPANTS The study included 708 adult liver transplantations performed from 2008 to 2013. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS EACA administration was not associated with incidences of intracardiac thrombosis/pulmonary embolism (1.3%) or intraoperative death (0.6%). Logistic regression (n = 708) revealed 2 independent risk factors associated with myocardial ischemia (age and pre-transplant vasopressor use) and 8 risk factors associated with the need for post-transplant dialysis (age, female sex, redo orthotopic liver transplantation, preoperative sodium level, pre-transplant acute kidney injury or dialysis, platelet transfusion, and re-exploration within the first week after transplant); EACA was not identified as a risk factor for either outcome. One-year survival rates were similar between groups: 92% in EACA-treated group versus 93% in the EACA-nontreated group. CONCLUSIONS The antifibrinolytic, EACA, was not associated with an increased incidence of thromboembolic complications or postoperative acute kidney injury, and it did not alter 1-year survival after liver transplantation.

Patent foramen ovale and intracardiac thrombus identified by transesophageal echocardiography during liver transplantation

Vascular anastomosis was completed, and the vascular crossclamps were removed to establish hepatic reperfusion (stage III) after only 24 minutes of warm ischemia time and 261 minutes of cold ischemia time. Reperfusion during the first minute was tolerated well, with a BP of 110/60 mmHg, HR of 110 beats/min, SaO2 of 100% on 100% FIO2, systolic/diastolic PAP of 30/18 mmHg, CVP of 10 mmHg, CI of 5.5 L/min/m2, and SvO2 of 81%. Five minutes after reperfusion, the patient’s BP suddenly decreased to 81/42 mmHg with an associated HR of 58 beats/min. A TEE revealed a large free-floating thrombus in the right atrium. The thrombus started in the inferior vena cava (IVC) (Video 2), extended into the PFO (Video 3), and was partially obstructing the tricuspid valve and right ventricular inflow (Video 4). The thrombus position was highly concerning given that a massive embolus could occur. If the thrombus further migrated into the left atrium through the PFO (Fig 2), then the potential of a systemic embolus existed. If the thrombus migrated into the right ventricle, then the potential of a massive pulmonary embolus existed. The surgeon was notified, and suction of the venous anastomosis site was initiated in order to decrease the right atrial pressure. The BP was increased with intravenous epinephrine, 50 g, in order to increase the left atrial pressure, with the aim to keep a left-toright shunt through the PFO and maintain the thrombus in the right atrium. During this time, unfractionated heparin (2,000 U 2 boluses) was given at 5-minute intervals in order to stabilize the clot formation, which resulted in rapid resolution of the clot from the right ventricle inflow only 10 minutes after clot detection. No clinical signs of pulmonary embolism were noted because PAPs remained within normal limits with no right ventricular dysfunction and no wall motion abnormality on TEE.

Perioperative coagulation management in liver transplant recipients

Abstract We review contemporary coagulation management for patients undergoing liver transplantation. A better understanding of the complex physiologic changes that occur in patients with end-stage liver disease has resulted in significant advances in anesthetic and coagulation management. A group of internationally recognized experts have critically evaluated current approaches for coagulopathy detection and management. Strategies for blood component and factor replacement have been evaluated and recommended therapies proposed. Pharmacologic treatment and prevention of coagulopathy, management of patients receiving antiplatelet medications, and the role of transesophageal echocardiography for early detection and management of thromboses are presented.

Thromboprophylaxis With Heparin During Orthotopic Liver Transplantation: Comparison of Hepcon HMS Plus and Anti-Xa Assays for Low-Range Heparin

OBJECTIVES The purpose of this study was to compare the agreement between two heparin assays, Hepcon HMS plus/Kaolin-ACT and Anti-Xa, and their predictive power in detecting circulating heparin levels post-reperfusion of the liver graft when compared with thromboelastogram (TEG) r time ratio in patients undergoing orthotopic liver transplantation (OLT). DESIGN Prospective, observational cohort study design. SETTING Single center, university hospital. PARTICIPANTS Thirty-eight consecutive adults who had undergone liver transplant. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS Paired arterial blood samples were collected before surgical incision, 5 minutes after administration of an average dose of 2,054±771 units of intravenous unfractionated heparin before caval cross-clamping, 5 minutes after portal reperfusion, 5 minutes after hepatic artery reperfusion, and 1 hour after hepatic artery reperfusion. The observations that heparin assay measurements were within the predetermined limits of agreement, strongly suggested the two heparin assays (Hepcon HMS plus and Anti-Xa assay) are interchangeable during prophylactic heparin dose therapy during OLT. Post-reperfusion, receiver operating characteristic curve analysis revealed high accuracy in measuring circulating heparin levels with both Anti-Xa and Hepcon HMS assays when compared with the TEG r time ratio assay. CONCLUSIONS The point-of-care Hepcon HMS plus/Kaolin-ACT (activated clotting time) assay appeared to be a reliable alternative to the more expensive and laboratory-required Anti-Xa assay in monitoring the response to intravenous heparin in patients undergoing OLT.

Isolated small bowel transplantation outcomes and the impact of immunosuppressants: Experience of a single transplant center.

AIM To investigate patient and graft outcomes in isolated small bowel transplant (SBTx) recipients and immunosuppressant induction agent impact on outcomes. METHODS A retrospective review of the perioperative data of patients who underwent SBTx transplant during an 8-year period was conducted. The intraoperative data were: patient demographics, etiology of short gut syndrome, hemodynamic parameters, coagulation profiles, intraoperative fluid and blood products transfused, and development of post-reperfusion. The postoperative data were: hospital/intensive care unit stays, duration of mechanical ventilation, postoperative incidence of acute kidney injury, and 1-year patient and graft outcomes. The effects of the three immunosuppressant induction agents (Zenapax, Thymoglobulin, Campath) on patient and graft outcomes were reviewed. RESULTS During the 8-year period there were 77 patients; 1-year patient and graft survival were 95% and 86% respectively. Sixteen patients received Zenapax, 22 received Thymoglobulin, and 39 received Campath without effects on patient or graft survival (P = 0.90, P = 0.14, respectively). The use of different immune induction agents did not affect the incidence of rejection and infection during the first 90 postoperative days (P = 0.072, P = 0.29, respectively). The Zenapax group received more intraoperative fluid and blood products and were coagulopathic at the end of surgery. Zenapax and Thymoglobulin significantly increased serum creatinine at 48 h (P = 0.023) and 1 wk (P = 0.001) post-transplant, but none developed renal failure or required dialysis at the end of the first year. CONCLUSION One-year patient and graft survival were 95% and 86%, respectively. The use of different immunosuppressant induction agents may affect the intraoperative course and short-term postoperative morbidities, but not 1-year patient and graft outcomes.

Society for the Advancement of Transplant Anesthesia: Liver Transplant Anesthesia Fellowship—White Paper Advocating Measurable Proficiency in Transplant Specialties Training:

The anesthesia community has openly debated if the care of transplant patients was generalist or specialist care ever since the publication of an opinion paper in 1999 recommended subspecialty training in the field of liver transplantation anesthesia. In the past decade, liver transplant anesthesia has become more complex with a sicker patient population and evolving evidence-based practices. Transplant training is currently not required for accreditation or certification in anesthesiology, and not all anesthesia residency programs are associated with transplant centers. Yet there is evidence that patient outcome is affected by the experience of the anesthesiologist with liver transplants as part of a multidisciplinary care team. Requests for a formal review of the inequities in training opportunities and requirements led the Society for the Advancement for Transplant Anesthesia (SATA) to begin the task of developing post-graduate fellowship training recommendations. In this article, members of the SATA Working Group on Transplant Anesthesia Education present their reasoning for specialized education and conclusions about which pathways can better prepare trainees to care for complex transplant patients.

Long-Term Cardiac Morbidity and Mortality in Patients With Aortic Valve Disease Following Liver Transplantation: A Case Matching Study

Introduction. This retrospective study examined the role of aortic valve (AV) disease in patients who underwent orthotopic liver transplantation (OLT) to determine the incidence of postoperative cardiac morbidity and mortality when compared with a matched control group without AV disease. Methods. Patients were included in the AV group if diagnosed with aortic stenosis (AS) or aortic regurgitation or had received AV replacement prior to OLT. The AV group (n = 53) was matched to a control group (n = 212) with the following preoperative variables: type of organ transplanted, age, gender, race, body mass index, MELD, redo-transplantation, preoperative renal replacement therapy, nonalcoholic steatohepatitis, viral hepatitis, diabetes, and coronary artery disease. A 1:4 ratio was utilized to improve the efficiency and power of the analysis. Results. No significant difference in survival or posttransplant cardiac complications (acute coronary syndrome, heart failure, or dysrhythmia) was observed between groups. However, statistically significantly more patients—11% (6/53)—required coronary intervention following OLT in the AV group, whereas 3% (7/212) required coronary intervention (χ2 = 5.8; P = .0156) in the control group. Following OLT, 9% (5/53) in the AV group required surgical or nonsurgical AV intervention, whereas no valvular events were observed in the control group. Event-free survival in the AV group, with an end point defined as AV intervention (n = 5) and death (n = 10), was 92% (49/53) at 1 year, 83% (44/53) at 3 years, and 72% (38/53) at 5 years. Conclusions. Patients with pretransplant AV replacement or AS have significant cardiac complications (myocardial infarction, AV replacement, or cardiac death) in 1 to 3 years post-OLT.