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Showing papers by "Niels Rahe-Meyer published in 2010"


Journal ArticleDOI
TL;DR: Fibr inogen concentrate was effective in increasing plasma fibrinogen level, and contributed to the correction of bleeding after cardiovascular surgery.
Abstract: Background. Normalization of plasma fibrinogen levels may be associated with satisfactory haemostasis and reduced bleeding. The aim of this retrospective study was to assess fibrinogen recovery parameters after administration of fibrinogen concentrate (Haemocomplettan w P) to patients with diffuse bleeding in cardiovascular surgery. Data on transfusion and patient outcomes were also collected. Methods. Patient characteristic and clinical data were obtained from patient records. Results of the thromboelastometry (FIBTEM w ) and of the standard coagulation tests, including plasma fibrinogen level, measured before surgery, before and after haemostatic therapy, and on the following day, were retrieved from laboratory records. Results. Thirty-nine patients receiving fibrinogen concentrate for diffuse bleeding requiring haemostatic therapy after cardiopulmonary bypass were identified. The mean fibrinogen concentrate dose administered was 6.5 g. The mean fibrinogen level increased from 1.9 to 3.6 g litre 21 (mean increment of 0.28 g litre 21 per gram of concentrate administered); maximum clot firmness increased from 10 to 21 mm. The mean fibrinogen increase was 2.29 (SD 0.7) mg dl 21 per mg kg 21 bodyweight of concentrate administered. Thirty-five patients received no transfusion of fresh-frozen plasma (FFP) or platelet concentrate after receiving fibrinogen concentrate; the remaining four patients received platelet concentrate intraoperatively. Eleven patients received platelets, FFP, or both during the first postoperative day. No venous thromboses, arterial ischaemic events, or deaths were registered during hospitalization. Conclusions. In this retrospective study, fibrinogen concentrate was effective in increasing plasma fibrinogen level, and contributed to the correction of bleeding after cardiovascular surgery. Br J Anaesth 2010; 104: 555‐62

183 citations


Journal ArticleDOI
TL;DR: During acidosis and hypothermia, acidosis should be corrected first; desmopressin can be administered to improve platelet function as a bridge until normothermia can be achieved.
Abstract: Summary Hypothermia and acidosis lead to an impairment of coagulation. It has been demonstrated that desmopressin improves platelet function under hypothermia. We tested platelet function ex vivo during hypothermia and acidosis. Blood samples were taken from 12 healthy subjects and assigned as follows: normal pH, pH 7.2, and pH 7.0, each with and without incubation with desmopressin. Platelet aggregation was assessed by multiple electrode aggregometry. Baseline was normal pH and 36 C. The other samples were incubated for 30 min and measured at 32 C. Acidosis significantly impaired aggregation. Desmopressin significantly increased aggregability during hypothermia and acidosis regardless of pH, but did not return it to normal values at low pH. During acidosis and hypothermia, acidosis should be corrected first; desmopressin can then be administered to improve platelet function as a bridge until normothermia can be achieved.

40 citations


Journal ArticleDOI
TL;DR: It is suggested that MEA and thromboelastometry reflect impairment of coagulation in cardiac surgery performed on different types of HLM and that platelet function is less affected by MECC than by standard HLM.
Abstract: The cardiopulmonary bypass (CPB) used in heart surgery has a deleterious effect on hemostasis. The aim of our study was to assess by means of standard laboratory and point-of-care methods changes induced by CPB in coagulation parameters, particularly in platelet function, and to determine whether these changes differ depending on the type of heart-lung machine (HLM) used: minimal extracorporeal circulation system (MECC) and standard HLM. The study enrolled 88 patients scheduled for coronary artery bypass surgery performed on pump. Forty-four interventions were performed with MECC and 44 with standard HLM. Blood was sampled preoperatively, after 30 min on CPB, after weaning from CPB, and 24 h postoperatively. Coagulation and platelet function were assessed using multiple electrode aggregometry (MEA), rotation thromboelastometry, as well as standard laboratory tests. Rotation thromboelastometry and standard laboratory reflected significantly impaired hemostasis after weaning from CPB but no significant differences between the two groups at different time points. Aggregation decreased significantly in both groups as early as 30 min after the institution of CPB (P < 0.05, Mann-Whitney U-test) and recovered within the first 24 h postoperatively, without reaching the preoperative level. Intraoperatively, aggregometry values reflected a significantly more severe reduction of platelet function in standard HLM group than in the MECC group (P < 0.01, ProcMixed test). Our findings suggest that MEA and thromboelastometry reflect impairment of coagulation in cardiac surgery performed on different types of HLM and that platelet function is less affected by MECC than by standard HLM.

25 citations


Journal ArticleDOI
TL;DR: Multiple electrode aggregometry appeared more useful and easier to apply than CPA for preoperatively identifying patients with platelet concentrates transfusion in cardiac surgery.
Abstract: Platelet dysfunction is an important cause of bleeding early after cardiac surgery. Whole-blood multiple electrode aggregometry (MEA), investigating the adhesion and aggregation of activated platelets onto metal electrodes, has shown correlations with platelet concentrates transfusion in this setting. Platelet activity in vivo is dependent on shear stress, an aspect that cannot be investigated with MEA, but with the cone and plate(let) analyzer (CPA) Impact-R that measures the interaction of platelets and von Willebrand factor (vWF) in whole blood under shear. We hypothesized that preoperative CPA may show better correlation with platelet concentrates transfusion post-cardiac surgery than MEA, since it is dependent on both platelet activity and platelet interaction with vWF multimers. Blood was obtained preoperatively from 30 patients undergoing aorto-coronary bypass (ACB) and 20 patients with aortic valve (AV) surgery. MEA was performed in hirudin-anticoagulated blood. The Impact-R analyses were performe...

24 citations


Journal ArticleDOI
TL;DR: The results confirm the lower stabilizing effect of gelatin on circulation during fluid resuscitation and the blood coagulation was mostly impaired due to HES 200/0.5 confirmed by the multiplate®-analysis as well as by different clinical findings.
Abstract: The constantly growing amount of different kinds of colloid fluids necessitates comparative investigations with regards to the safety and effectivity in clinical use of these preparations. Hence we compared three colloid fluids in an observational study. The objective was the exploration of the influence of these three colloids on blood coagulation, hemodynamics and renal function of the cardiac surgical patient. We included 90 patients undergoing an elective open-heart surgery with the use of the heart-lung machine and observed them consecutively. Group 1 [gelatin 4% (n = 30)], Group 2 [HES 200/0,5 (n = 30)] and Group 3 [HES 130/0,42 (n = 30)]. We measured the perioperative volume replacement, the administration of blood- and coagulation-products, the application of catecholamines, the renal function, blood gas and the platelet aggregation using multiplate electrode analyzer (Multiplate®, Dynabyte medical, Munich, Germany). The gelatin-group needed significantly more norepinephrine than the HES 130/0.42 group. The responsible surgeon considered the blood coagulation in the HES 200/0.5 group most frequently as impaired. Furthermore we saw a significant decrease in platelet function in the HES 200/0.5 group when performing the multiplate®-analysis (ADP-and COL-test). HES 130/0.4 as well as gelatin 4% showed no significant change in platelet function. The gelatin-group and the HES 200/0.5 needed significantly more aprotinine than the HES 130/0.4 group. We saw no significant difference with regards to administration of blood and coagulation products between the three groups. The urinary excretion during the intervention was significantly higher in the HES 200/0.5 group and in the gelatin group than in the HES 130/0.4 group. Our results confirm the lower stabilizing effect of gelatin on circulation during fluid resuscitation. The blood coagulation was mostly impaired due to HES 200/0.5 confirmed by the multiplate®-analysis as well as by different clinical findings.

17 citations


Journal ArticleDOI
TL;DR: The electrical skin impedance measurement may be used to monitor the effects of anesthetics during general anaesthesia, and significant changes of BIS, HR and blood pressure were observed as well.
Abstract: Objective Sympathetic stimulation leads to a change in electrical skin impedance. So far it is unclear whether this effect can be used to measure the effects of anaesthetics during general anaesthesia. The aim of this prospective study is to determine the electrical skin impedance during induction of anaesthesia for coronary artery bypass surgery with fentanyl and etomidate.

2 citations