The International Journal of Artificial Organs

Arteriovenous fistula dysfunction is a constant problem in chronic hemodialysis patients. We investigated the factors influencing fistula dysfunction in 184 patients on chronic hemodialysis. Stepwise regression analysis and Cox proportional hazards model were used to assess the relationship between fistula dysfunction and age, sex, duration of hemodialysis, diabetes mellitus, hematocrit, serum creatinine, blood urea nitrogen, KW, prothrombin time, blood pressure, anticoagulant therapy, dose of erythropoietin, calcium channel blocker therapy, and angiotensin-converting enzyme inhibitor therapy. Fistula dysfunction showed a significant relationship with a low systolic blood pressure, a low hematocrit, the presence of diabetes mellitus, and angiotensin-converting enzyme inhibitor therapy. These results suggested that treatment with angiotensin-converting enzyme inhibitors may help to prevent fistula dysfunction.

A 64-year-old woman presented with coma and shock due to severe ethanol intoxication. Her initial, markedly elevated blood alcohol level of 136.5 mM fell only by 16% after a 4-hour period of conservative treatment consisting of mechanical respiration and the administration of intravenous fluids, vasopressors and inotropics. Subsequent hemodialysis rapidly reduced her blood ethanol concentrations to less threatening levels, with prompt restoration of her consciousness. Hemodialysis may be life-saving and should be considered in patients with severe ethanol intoxication.

Cardiac output estimation is a very important study for the artificial heart. In this paper, we developed a cardiac output estimation model for the moving-actuator type total artificial heart (MA-TAH) that was developed at Seoul National University Hospital. The proposed model is simple and provides beat-by-beat mean cardiac output estimation. Moreover, it uses non-invasively acquired signals. Model parameters were adjusted with in vitro data by least mean square (LMS) algorithm. Results showed that the proposed scheme gives a mean estimation error of about 0.1 (l/min) for the given data. This ensures the suitability of the proposed model.

Patients with severe acute alcoholic hepatitis develop multiple organ failure which is associated with production of inflammatory cytokines and a poor prognosis. The aim of the present pilot study was to evaluate the effects of the BioLogic-DT sorption-suspension dialyser in patients with severe acute alcoholic hepatitis. Ten patients with encephalopathy (grade II-IV) were entered into the study, 5 received treatment with the BioLogic-DT for 6 hours daily for 3 days and 5 received conventional treatment as controls. The system was biocompatible with no adverse effects on blood pressure or platelet counts, factor V, fibrinogen or antithrombin III. No bleeding episodes were observed even with the use of small doses of heparin. After 3 days, blood ammonia was lower in the BioLogic-DT treated patients than in the controls, although blood lactate was higher. There were slight increases in plasma TNF and IL-8 during treatment over and above the higher levels present initially, possibly as a result of activation of white cells in the extracorporeal circuit. The further development of the BioLogic-DT dialyser with the addition of a plasma treatment module capable of removing cytokines would be worth evaluating in acute alcoholic hepatitis.

Axisymmetric drop shape analysis by profile (ADSA-P) was used to assess in time contact angle changes of human plasma drops placed on four different biomaterials. Results were related with conventional blood compatibility measurements: albumin adsorption, fibrinogen adsorption and platelet adhesion. While contact angle measurements with water are material-related but constant in time, contact angle measurements with plasma changed over time owing to protein adsorption on the solid-liquid interface. The contact medium plasma did not influence the initial contact angle. Contact angles on PDMS decreased most in time (41 degrees) and demonstrated highest levels of conventionally measured albumin and fibrinogen adsorption and platelet adhesion. PTFE, with the lowest contact angle decrease over a 500 minutes period (19 degrees), showed low fibrinogen and albumin adsorption as well as low platelet adhesion. PU and HDPE demonstrated almost similar initial contact angles with plasma and contact angle decreases (26 and 27 degrees), intermediate protein adsorption, and platelet adhesion. We conclude that biocompatibility properties of the tested materials may be more related to the behaviour of their contact angles in time, than to the initial hydrophobic or hydrophilic state.

We investigated 19 patients affected by chronic peripheral neurological disorders treated with therapeutic plasma exchange (TPE) to verify the efficacy of the therapeutic protocol used in these diseases.

Every patient was clinically considered after 5 TPE. Those who showed an improvement started chemotherapy and continued TPE at the rate of 2 procedures/week for 2 weeks, then 1 procedure/week for 1 month and finally 1 procedure every 2 weeks for 2 months. Intravenous immunoglobulins (IVIg) were infused at the end of apheretic treatment in one of the patients affected by neurological disorders due to monoclonal gammopathy undetermined significance. HCV-positive patients with cryoglobulins were treated with α-interferon (α-IFN) for 6 months before TPE. Eleven patients (58%) had a symptomatic improvement, 2 (1.5%) stopped TPE treatment owing to side effects and 6 (31.5%) did not respond to apheretic therapy.

In order to improve the advantages of TPE we suggest using IVIg at the end of apheretic therapy, while in HCV-positive patients, at least one year of α-IFN therapy is required before initiating TPE.

In this prospective, randomised, double-blind study, we investigated the effect of epidural anaesthesia and an antifibrinolytic agent, Aprotinin (500,000 KIU in bolus before surgery and 500,000 KIU h-¹ in drip form during surgery), on intra and postoperative blood loss and transfusion requirements in total hip arthroplasty. Sixty patients were allocated randomly to four groups (A: epidural + general anesthesia + Aprotinin, B: epidural + general anesthesia + placebo (equal volume), C: general anaesthesia + Aprotinin, D: general anaesthesia + placebo). Postoperative analgesia: epidural analgesia in groups A and B, systemic analgesia with opiates in groups C and D.

Blood loss during surgery was monitored and salvaged with the Compact-A Dideco, and postoperative blood loss with the BT 797 Recovery Dideco for the first 24 hours. Perioperative blood loss, frequency and quantity of transfusions were significantly higher in group D (p < 0.0001). Total blood loss was reduced by 31.3% by epidural anaesthesia, 20.4% by Aprotinin and 51.4% using a combination of the two techiniques.