Evaluation of a New Software Version of the FloTrac/Vigileo (Version 3.02) and a Comparison with Previous Data in Cirrhotic Patients Undergoing Liver Transplant Surgery

Abstract: BACKGROUND: Reliable cardiac output monitoring is particularly useful in the cirrhotic patient undergoing liver transplant surgery, because cirrhosis of the liver is associated with a vasodilated and high output state, known as cirrhotic cardiomyopathy, that challenges the reliability of pulse contour cardiac output technology. The contractility of the ventricle in cirrhosis is impaired, which is tolerated even though the ejection fraction and cardiac output are elevated because of the low peripheral resistance. However, during surgery the cirrhotic patient can decompensate because of the physiological changes and stress of surgery. Recently, we showed that the FloTrac/Vigileo (TM) failed to perform in cirrhotic patients undergoing transplant surgery. In response, the company upgraded their software. Therefore, we have assessed the accuracy and reliability of this new third-generation (version 3.02) FloTrac/Vigileo algorithm software in the same setting. METHODS: The cardiac index was measured simultaneously by single-bolus thermodilution (CI(TD)), using a pulmonary artery catheter, and pulse contour analysis, using the FloTrac/Vigileo (CI(V)). Readings were made at 10 time points during and after liver transplant surgery in 21 patients. Comparisons with data from our 2009 study, which used second-generation (version 01.10) software, were also made. RESULTS: Our new data show that version 3.02 software significantly reduced the adverse effect on pulse contour cardiac output reading bias in low peripheral resistance states, and thus improves the overall precision and trending ability of the system. Regression analysis between CI(TD) and CI(V) showed that the correlation was moderate (r = 0.67, 95% confidence interval, 0.40 to 0.86). The Bland and Altman analysis showed that bias was 0.4 L.min(-1).m(-2), and the percentage error was 52% (95% confidence interval, 49% to 55%). Trending ability of the new software also was improved but was still well below the current benchmarks. CONCLUSION: The new software (version 3.02) provided substantial improvements over the previous versions with better overall precision and trending ability. Further algorithm refinements will increase this technology's reliability to be extensively used in the highly complex setting of cirrhotic patients undergoing liver transplantation. (Anesth Analg 2011; 113: 515-22

Liver transplantation due to Herpes Simplex virus-related sepsis causing massive hepatic necrosis after thoracoscopic thymectomy

Following thorascopic thymectomy performed because of myasthenia gravis, a 25-year-old man was affected by fulminant hepatic failure (FHF) of unknown etiology. He was then transferred to our department, where his clinical situation worsened with the onset of renal failure, shock, coagulopathy and coma. Given the young age of the patient, the immediate availability of a donor, and the absence of a definite diagnosis of sepsis at the time, it was decided to proceed with liver transplantation. The results of a polymerase chain reaction (PCR) test (a technique that was unavailable at the referring hospital), which arrived only a few hours later, indicated the presence of herpes simplex virus (HSV) DNA in several of the patient's samples; this led to the formulation of a diagnosis of FHF due to HSV. It is worth noting that HSV-IgM and HSV-IgG assays had always been negative in this patient. Despite acyclovir therapy with initially encouraging clinical results, the patient died several days later because the viral infection had spread to the graft, lungs, heart, spleen, stomach and kidneys. Since evaluating antibody response is not always useful in diagnosing HSV infection, and particularly if PCR methodology is unavailable, it is worth initiating early empiric antiviral therapy when the etiology of FHF is indeterminate This is because the timeliness of treatment while awaiting virological confirmation may be critical to survival. If a liver transplantation becomes mandatory, careful consideration should be given to the extent of the viral infection and its response to therapy because of the possibility of viral spread to the graft

Regional filter heparinization for continuous veno-venous hemofiltration in liver transplant recipients

AIM: To study safety, clinical and operative feasibility of continuous veno-venous hemofiltration (CVVH) with anticoagulation only of the filter in patients at risk for bleeding. METHODS: This prospective, comparative, non randomised study was completed at an intensive care unit of a teaching NHS hospital. Sixteen liver transplant (LT) recipients with acute renal failure needing CVVH were treated with a regional anticoagulation protocol (heparin and protamine were administered respectively pre- and post-filter) and compared to 11 critically ill subjects who received a standard low-heparin treatment. Activated coagulation time (ACT) monitoring was used to adjust anticoagulation and heparin neutralization. RESULTS: Mean circuit life was 35.8+/-13.6 hours (95% CI 28.5-43.1) in patients receiving regional anticoagulation and 34.4+/-14 hours in controls (95% CI 25.5-43.3; p=0.7). Fourty-eight circuits (47.5% of the total) in the heparin-protamine group had a life-span longer than 30 hours and other 22 (21.7%) were changed intentionally after 24 hours of use in absence of clots. None of the patients in both the studied groups had bleeding or hemodynamic complications and their azotemic control was always satisfactory. CONCLUSION: In LT recipients, regional anticoagulation can achieve a circuits life-span comparable to that from systemic anticoagulation with satisfactory safety and simplicity of use

Transcranial Doppler Sonography is Useful for the Decision-Making at the Point of Care in Patients with Acute Hepatic Failure: A Single Centre's Experience

Acute hepatic failure (ALF) is an uncommon disease characterized by a rapid deterioration of the hepatic function with severe derangements of the mental status in previously healthy subjects due to massive hepatocytes necrosis. Neurological impairment, due to intracranial hypertension and cerebral ischemia, is a key factor because it is a main criterion to decide when to proceed to liver transplantation, which is only treatment for these patients. Therefore, neurological monitoring holds an essential role in the clinical management of ALF patients but it needs to be performed at the point-of-care in the majority of the cases as such critically ill patients cannot be moved away from the ICU because they frequently need continuous hemodynamic, ventilatory and renal support. We herein report and discuss our experience relating to the use of transcranial sonography as a neuro-monitoring tool in ALF patients. In our series this technique allowed a repeatable and reliable non-invasive assessment of cerebral blood flow changes at the bedside thus avoiding the complications associated with the use of an intracranial probe to measure intra-cranial pressure and making it possible to correctly evaluate the timing and feasibility of liver transplantation

Intraabdominal pressure in liver transplant recipients: incidence and clinical significance

Abstract BACKGROUND: The incidence and clinical relevance of increased intraabdominal pressure after orthotopic liver transplantation (OLT) has not yet been evaluated despite the finding that occurrence of this condition in postsurgical critically ill patients may impair various organ functions. The aim of this study was to assess whether the occurrence of abdominal hypertension among a population of OLT recipients was an important cofactor producing early postoperative complications. METHOD: This prospective clinical study measured abdominal pressure every 6 hours during the intensive care unit (ICU) stay using the urinary bladder method. A value of >/=25 mm Hg was considered high. Hemodynamic status was simultaneously evaluated and renal function assessed based on the hourly urinary output, and by calculating serum creatinine on postoperative days 2 and 4. Renal failure was defined as a serum creatinine level of >1.5 mg/dL, or an increase in peak of >1 mg/L within 72 hours of surgery. The filtration gradient and patient outcomes were also considered. RESULTS: Intraabdominal hypertension was observed in 32% of cases. The subjects displaying high IAP showed significantly lower artery pressure values (P <.01), but did not differ in terms of central venous pressure or cardiac output. High intraabdominal pressure was more frequently associated with renal failure (P <.01), a lower filtration gradient (P <.001), delayed postsurgical weaning from the ventilation (P <.001), and increased ICU mortality (P <.05). A receiver operator characteristic curve analysis showed that the critical IAP values, namely those with the best sensitivity/specificity, were 23 mm Hg for postoperative ventilatory delayed weaning (P <.05), 24 mm Hg for renal dysfunction (P <.05), and 25 mm Hg for death (P <.01). CONCLUSIONS: Abdominal hypertension occurs frequently after OLT and may be associated with a complicated postoperative course. Comment i