Annabel Blasi

An assessment of thromboelastometry to monitor blood coagulation and guide transfusion support in liver transplantation

BACKGROUND: Rotation thromboelastometry (TEM) has been proposed as a convenient alternative to standard coagulation tests in guiding the treatment of coagulopathy during orthotopic liver transplantation (OLT). This study was aimed at assessing the value of TEM in monitoring blood coagulation and guide transfusion support in OLT.

Anesthetic management of a patient in prone position with a drill bit penetrating the spinal canal at C1-C2, using a laryngeal mask

UNLABELLED Airway management in patients with penetrating neck trauma must guarantee cervical spine stability. Moreover, the prone position increases the risk of difficult ventilation and cervical spine injury. A 19-yr-old patient was brought to the emergency room in prone position with a drill bit protruding from the posterolateral aspect of his neck. The bit had entered the spinal canal below the first cervical vertebra, and placed near the odontoid peg. He was referred for surgical removal of the drill. The use of an inhaled induction of anesthesia, avoiding muscle relaxants, and ventilation through a laryngeal mask airway inserted in the prone position seemed to offer a satisfactory approach. IMPLICATIONS Management of patients with penetrating neck trauma must guarantee cervical spine stability. Moreover, the prone position increases the risk of difficult ventilation and cervical spine injury. Anesthesia may be induced and the airway can be managed with the patient already in the prone position for surgery.

Impact of deep sedation on the accuracy of hepatic and portal venous pressure measurements in patients with cirrhosis.

Measurement of the hepatic venous pressure gradient (HVPG) offers valuable prognostic information in patients with cirrhosis. In specific circumstances, (children, agitated patients, TIPS placement) deep sedation is required. This study aims to assess the impact of deep sedation on the accuracy of hepatic/portal pressure measurements.

Impact of Preemptive Fibrinogen Concentrate on Transfusion Requirements in Liver Transplantation: A Multicenter, Randomized, Double-Blind, Placebo-Controlled Trial

We hypothesized that preemptive fibrinogen administration to obtain an initial plasma level of 2.9 g/L would reduce transfusion requirements in liver transplantation. A randomized, multicenter, hemoglobin‐stratified, double‐blind, fibrinogen‐versus‐saline–controlled trial was conducted. The primary end point was the percentage of patients requiring red blood cells. We evaluated 51 patients allocated to fibrinogen and 48 allocated to saline; the primary end point was assessed using data for 92 patients because the electronic record forms were offline for three patients in the fibrinogen group and four in the saline group. We injected a median of 3.54 g fibrinogen preemptively in the fibrinogen group. Nine patients in the saline group (20.9%) required fibrinogen at graft reperfusion (compared with one patient [2.1%] in the fibrinogen group; p = 0.005). Blood was transfused to 52.9% (95% confidence interval [CI] 42.5–63.3%) in the fibrinogen group and 42.74% (95% CI 28.3–57.2%) in the saline group (p = 0.217). Relative risk for blood transfusion was 0.80 (95% CI 0.57–1.13). Thrombotic events occurred in one patient (2.1%) and five patients (11.4%) in the fibrinogen and saline groups, respectively. Seven patients (14.6%) in the fibrinogen group and nine (20.3%) in the saline group required reoperation. Preemptive administration of fibrinogen concentrate did not influence transfusion requirements.

The use of β-adrenergic drugs improves hepatic oxygen metabolism in cirrhotic patients undergoing liver resection

BACKGROUND & AIMS Hepatic resection is associated with hemodynamic and oxygen metabolism disturbances of the residual liver resulting from liver regeneration. In underlying liver disease, the remnant liver responds inadequately to increased energy demands leading to a less efficient recovery process. The aim of this study was to assess the effect of vasoactive drugs on hepatic oxygen metabolism and hemodynamics in cirrhotic patients that have undergone liver resection. METHODS Thirty patients were randomly allocated to receive peri-operatively low doses (4 microg/kg/min) of dopamine (DaG, n=10), dobutamine (DbG, n=10) or saline (CG, n=10). Hepatic hemodynamics, hepatic oxygen metabolism and lactate uptakes were evaluated before drug administration and at the time of abdominal closure. Post-operative liver function and outcome were recorded. RESULTS The peri-operative use of vasoactive drugs preserved total hepatic blood flow and hepatic compliance, even increasing in patients who received Db, whereas those parameters decreased in CG after liver resection. At this time, oxygen delivery and consumption decreased in CG patients, but were unchanged when vasoactive drugs were used. In all groups, lactate uptake decreased sharply and only DbG showed positive lactate extraction capacity. The peak of post-operative bilirubin, which resumed baseline values more quickly in DbG, inversely correlated with intra-operative hepatic compliance and hepatic oxygen extraction. CONCLUSION Low doses of vasoactive drugs, especially dobutamine, improved hepatic oxygen supply and uptake preserving immediate function of the remnant cirrhotic liver.

Risk factors and outcomes of failed endoscopic retrograde cholangiopancreatography in liver transplant recipients with anastomotic biliary strictures: A case‐control study

Anastomotic strictures (ASs) of the biliary duct after liver transplantation (LT) are primarily managed with endoscopic retrograde cholangiopancreatography (ERCP), but in some cases, this fails because of difficulties in passing the strictures. The aim of this case‐control study was to examine specific risk factors for initial ERCP failure and the outcomes of percutaneous transhepatic cholangiography (PTC) as a second‐line approach in LT recipients with ASs. Between January 2002 and December 2010, we identified LT recipients with ASs who experienced initial ERCP failure (which was defined as the inability to traverse the AS with guidewires in 2 or more consecutive procedures). A period‐matched control group (ratio = 1:2) with ASs and initial ERCP success was analyzed. Preoperative, intraoperative, postoperative, and endoscopic variables were evaluated as risk factors. The outcomes of PTC and the need for hepaticojejunostomy (HJ) or retransplantation were evaluated. Seventeen cases who experienced initial ERCP failure were compared with 34 controls. The median times from LT to ERCP were similar (8.7 months for cases and 8.6 months for controls, P = not significant). A multivariate analysis revealed that previous bile leaks [odds ratio (OR) = 6.07, 95% confidence interval (CI) = 1.0‐36.5] and more than 4 U of intraoperatively transfused red blood cells (OR = 11.51, 95% CI = 1.9‐71.2) were independent risk factors for failure. PTC was an effective second‐line treatment in only 3 of 12 cases (25%). The need for HJ was more frequent for the cases (13/17 or 76.5%) versus the controls (7/34 or 20.6%, P < 0.001). One patient in each group underwent retransplantation (P = not significant). In conclusion, previous bile leaks and high packed red blood cell transfusion requirements during surgery are risk factors for initial ERCP failure in LT recipients with ASs. A high proportion of these patients will need surgery as their final therapy. Liver Transpl 18:482–489, 2012.

Liver Transplant From Unexpected Donation After Circulatory Determination of Death Donors: A Challenge in Perioperative Management

Unexpected donation after circulatory determination of death (uDCD) liver transplantation is a complex procedure, in particular when it comes to perioperative recipient management. However, very little has been published to date regarding intraoperative and immediate postoperative care in this setting. Herein, we compare perioperative events in uDCD liver recipients with those of a matched group of donation after brain death liver recipients. We demonstrate that the former group of recipients suffers significantly greater hemodynamic instability and derangements in coagulation following graft reperfusion. Based on our experience, we recommend a proactive recipient management strategy in uDCD liver transplantation that involves early use of vasopressor support; maintaining adequate intraoperative levels of red cells, platelets, and fibrinogen; and routinely administering tranexamic acid before graft reperfusion.

Reliability of thromboelastometry for detecting the safe coagulation threshold in patients taking acenocoumarol after elective heart valve replacement

BACKGROUND Reversal of anticoagulation can be needed in patients undergoing heart valve surgery. ROTEM® has been correlated with international normalized ratio (INR) in patients on warfarin but not with patients on acenocoumarol. This study investigates the reliability of ROTEM® for detecting INR values below the 1.5 threshold in patients on acenocoumarol therapy. MATERIAL AND METHODS Patients on oral anticoagulation with acenocoumarol after elective heart valve replacement were prospectively included in the study. INR and the ROTEM® were measured simultaneously. ROTEM® parameters included coagulation time, clot formation time, alpha angle, and maximal clot firmness after tissue factor activation (EXTEM). Concordance between INR and ROTEM® was analyzed by Lins concordance coefficient (LCC) and the correlation with Spearmans rho. RESULTS Fifty-four consecutive patients (40 female; median age 67years) were included. Clotting time (CT) was the parameter that best correlated with INR (r=0.81, p<0,001), and LCC was substantial (0.67). CT was able to predict INR values above or below 1.5: area under curve=0.998. CT≥84seconds, corresponding to a cut-off for likelihood ratio (LR+)=5, had a sensitivity and specificity of 100% and 80%, respectively, to detect an INR below 1.5. For the same INR threshold, CT≥84seconds had a predictive positive value of 92.9% and a predictive negative value of 100%. CONCLUSION Our preliminary results suggest that CT≥84seconds in the EXTEM ROTEM® test is a feasible method for predicting an insufficient reversion of oral anticoagulant therapy in patients taking acenocoumarol after elective heart valve surgery.

Coagulation profile after plasma exchange using albumin as a replacement solution measured by thromboelastometry

Significant decrease in fibrinogen and other coagulation proteins is observed after plasma exchange when albumin is used as a replacement fluid. Little is known about how those changes impact on thromboelastometry (TEM). The aim of this study was to describe the changes in TEM after performing plasma exchange procedures using 5% albumin as a replacement fluid and its correlation with the standard coagulation tests.

Intraoperative Management of High-Risk Liver Transplant Recipients: Concerns and Challenges

Liver transplantation (LT) offers patients with liver disease a real chance for long-term survival. In the past decade, successful survival after LT along with the Model for End-Stage Liver Disease-based allocation policy have increased willingness to accept patients with a higher risk profile and marginal organs and to prioritize the sickest patients on the waiting list. Therefore, the anesthesiologist now deals with very challenging patients. In the present review, we aimed to highlight key aspects of intraoperative LT management in high-risk patients and to place these aspects in the perspective of their impact on perioperative outcomes. Conservative standardized perioperative strategies mandate a switch toward accurate and tailored perioperative anesthetic care to maintain the steady improvement in recipient survival rates after LT. In our opinion, continuous assessment of fluid status and cardiac performance, strategies promoting graft decongestion, rational hemostatic management, and the identification of LT recipients with potential risk of vascular complications should constitute the cornerstone of intraoperative management.