Assessment of haemostasis and impact of fibrinogen supplementation on clot properties using global haemostasis assays in patients on chronic dialysis.

BACKGORUND: Multifactorial haemostasis disorders are typical of patients with end-stage renal disease (ESRD) on chronic haemodialysis (HD). Thromboelastometry and impedance aggregometry allow for a comprehensive assessment of clot formation, lysis, and platelet (PLT) function. This study aims to determine the haemostatic profile in a group of patients with ESRD on chronic, interrupted dialysis, especially in terms of PLT function and the impact of in vitro fibrinogen concentrate supplementation on clot properties. METHODS: A total of 22 patients on chronic HD and 22 healthy controls (HC) were enrolled in the prospective study with a control group. Global haemostasis assays (GHA) were used to describe the haemostasis profile and to assess the effect of fibrinogen concentrate supplementation on improving clot quality. RESULTS: Despite the lack of considerable differences in the number of PLTs, there was a significantly lower potential of PLT aggregation in the HD group (922 ±163 AU*min). A higher concentration of fibrinogen was also observed in this group which presented considerably higher maximum clot firmness (MCF) FIBTEM (22 ±5.3 mm). Clotting time (CT) EXTEM was also prolonged (72 ±23 s). No hyperfibrinolysis was reported. In vitro fibrinogen concentrate supplementation resulted in significant improvement in MCF FIBTEM (30 mm vs. 22 mm; P < 0.001). However, it also led to a deterioration in PLT aggregation as assessed by TRAPtest. CONCLUSIONS: The haemostasis profile of ESRD patients demonstrates a limited potential of PLT aggregation, with no improvement after fibrinogen addition.

Multiple electrode aggregometry as a method for platelet function assessment according to the European guidelines.

Platelets play an essential role in haemostasis. Assessment of their function is vital for anaesthesiologists evaluating haemostatic potential, especially during emergency operations. The monitoring of platelets function had been implemented into the European recommendations for management of perioperative and posttraumatic bleeding. One of the diagnostic methods described in the recommendations is multiple electrode aggregometry. As antiplatelet therapy becomes more widely used in modern medicine, this method, in contrast to standard laboratory tests, can significantly help to identify patients with drug-induced thrombocytopaty. The aggregometry enables prompt evaluation of the platelets aggregation which is very useful for everyday decision-making in goal-directed hemostatic therapy.

The assessment of platelet function using multiple electrode aggregometry in practical procedures in anaesthesia.

BACKGROUND: Platelets are responsible for primary haemostasis. Patients with suspected platelet dysfunction require prompt clinical assessment when qualifying for emergency surgical procedures. The purpose of this article is to present our experience in platelet function assessment using whole-blood multiple electrode aggregometry (MEA) in various clinical conditions. CASE REPORTS: Retrospective analysis of three patients with thrombocytopathy associated with normal platelet counts was performed using standard laboratory tests complemented by MEA. In two cases, platelet dysfunction was due to antiplatelet drugs, while in one other case it was caused by chronic kidney disease. CONCLUSIONS: Anaesthesiologists strive to make the perioperative period as safe as possible. Platelet function assessment should be considered in every patient in whom haemostatic disturbances are suspected. MEA provides support for clinical decision-making, especially in patients who undergo haemodialysis or require antiplatelet therapy, and are in need of emergency surgery.

Is Hydroxyethyl Starch Irrelevant to Hemostasis in Patients Undergoing Liver Transplantation?--In vitro Analysis Based on Thromboelastometry.

BACKGROUND: Liver transplantation may be associated with severe bleeding that requires intensive fluid management. Aggressive fluid administration could result in hemodilution, triggering dilutional coagulopathy that intensifies bleeding. Colloids are plasma expanders used in daily practice. Fibrinogen, malfunctioning in liver cirrhosis, is the earliest decreasing clotting factor while bleeding. Fibrinogen supplementation is recommended as the first-choice therapy in such cases. Therefore, the influence of hemodilution on fibrin clot formation among patients with liver cirrhosis was analyzed, followed by the assessment of fibrinogen supplementation in clot restitution. MATERIAL AND METHODS: Blood collected from 22 patients with post-inflammatory liver cirrhosis was diluted up to 30% and 60% with crystalloid (0.9% NaCl) or colloid (6% hydroxyethyl starch 130/0.4), followed by fibrinogen supplementation corresponding to an overall dose of 4 g. The influence of hemodilution on plasma fibrinogen concentration and on thromboelastometry FIBTEM test was analyzed, as well as the influence of fibrinogen supplementation. RESULTS: Hemodilution lowers fibrinogen concentration and decreases fibrin clot formation. The higher the grade of dilution, the more profound the disturbances observed; 6% hydroxyethyl starch 130/0.4 cause more intense effect on fibrin clot formation than 0.9% NaCl. Fibrinogen supplementation improves fibrin clot formation as assessed in FIBTEM. CONCLUSIONS: Fibrinogen supplementation among patients with liver cirrhosis might improve fibrin clot formation during hemodilution. Fibrinogen supplementation might by considered as a possible treatment of coagulopathy during liver transplantation, but further clinical studies need to be performed.

Thoracic epidural analgesia in anaesthesia for liver transplantation: the 10-year experience of a single centre.

BACKGROUND: Improvements in operating techniques, methods of anaesthesia and postoperative care in liver transplantation (LT) contribute to better outcomes. In order to restrict postoperative mechanical ventilation, a thoracic epidural analgesia (TEA) has been performed in our centre since 2000. In this report we present our 10-year experience of using TEA as a component of LT anaesthesia. MATERIAL/METHODS: TEA was performed, by anaesthetists experienced in this method, on patients qualified for LT, who consented and met inclusion criteria: INR<1.5, APTT<45s and platelets >70 G/L. Since 2008 the decision to insert an epidural catheter has been additionally supported by thromboelastometry. We assessed extubation time, frequency of complications of TEA and undesired accidents. RESULTS: From 279 patients undergoing LT, TEA was performed on 67 (24%), and from these 56 (84%) were extubated in the operating theatre. There were 5 cases of unsatisfactory thoracic epidural analgesia. Only 1 epidural catheter was removed accidentally, on the 2nd postoperative day. None of the complications of TEA were observed in the TEA group. CONCLUSIONS: Based on our observations, it can be assumed that TEA done by experienced an anaesthetist is a safe component of anaesthesia in selected groups of patients undergoing LT, and allows for early extubation.