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Our 18-year old female patient suffered from microscopic polyangiitis. After invasive diagnostics, a diffuse alveolar hemorrhage occurred, leading to acute lung failure. In spite of differential ventilation, respiratory insufficiency and lactate-acidosis increased quickly. Due to the massive hemorrhage, a pumpless extracorporeal lung assist was implanted and, after six hours, low-dose heparinization was started. In response to this therapy, hypercapnia and acidosis improved quickly and were completely eliminated within 24 hours. Simultaneously, treatment with prednisolon and cyclophosphamid was started. After 7 days, the patient's conditions allowed weaning from the pumpless extracorporeal lung assist and after 9 days she was extubated. In conclusion, the pumpless lung assist was shown to be a very practical option to treat the most serious forms of hypercapnia, especially for patients disposed to diffuse bleeding.

Pump induced hemolysis is presently evaluated by measuring plasma free hemoglobin (fHb). However, this method has disadvantages because quantification of fHb depends on hematocrit (HCT) and hemoglobin (Hb) levels. The aim of this work was to devise a hemoglobin independent method, capable of quantifying cell trauma directly by measuring the number of red blood cell (RBC) fragments. Whole blood flow cytometry was used to quantify circulating RBC fragments derived from a roller pump (Sarns, Inc. Model 2 M 6,002) and a centrifugal pump (Gyro C1E3, Kyocera Corp.). The pumps were tested in a mock circuit for 2 hr (5 L/min flow against 100 mm Hg pressure head). Red blood cell fragments were quantified by a phycoerythrin (PE) labeled glycophorin A antibody specific for erythrocytes. Red blood cell fragments were smaller than the intact RBC population and overlapped in size with the platelet population (based on forward- and side-light scattering measurements). For the roller pump, the values for RBC fragments increased from 1,090 +/- 260/microl at 0 min to 14,880 +/- 5,900/microl after 120 min. In contrast, using the centrifugal pump, there was little increase in RBC fragments (from 730 +/- 270/microl at 0 min to 1,400 +/- 840/microl after 120 min). Flow cytometry can be used for the rapid, sensitive, hemoglobin independent evaluation of pump induced RBC trauma.

During cardiopulmonary bypass (CPB) mechanical stress and the contact of blood with artificial surfaces lead to the activation of pro- and anticoagulant systems and the complement cascade, and to changes in cellular components. This phenomenon causes the "postperfusion-syndrome", with leukocytosis, increased capillary permeability, accumulation of interstitial fluid, and organ dysfunction. In this study, we focused on the influence of the extracorporeal circulation, sternotomy, and heparin administration on the activation of coagulation and fibrinolysis. In 15 patients we investigated coagulation parameters before, during and post CPB, i.e., fibrinogen, antithrombin (AT) III, thrombin-antithrombin complex (TAT), prothrombin fragments F1 + 2 (F1 + 2), factor (F) XIIa, tissue factor (TF), and parameters of the fibrinolytic system, i.e., plasmin-antiplasmin-complex (PAP), D-dimer, tissue-plasminogen-activator (tPA), urokinase-type plasminogen activator (uPA), and plasminogen-activator inhibitor type 1 (PAI 1). The results demonstrate distinct alterations in the above mentioned parameters. Despite administration of a high dose of heparin (activated clotting time [ACT] > 450s) combined with a low dose of aprotinin, activation of the coagulation and fibrinolytic pathways was observed. We found this activation was mainly caused by CPB and not by sternotomy. The activation of coagulation was due to foreign surface contact (F XII => F XIIa) as well as to an effect of tissue factor release in the late phase of CPB. The enhanced fibrinolytic activity during CPB was, at least in part, caused by tPA and was followed by PAI 1 release.

After-bleeding not due to surgery following extracorporeal circulation (ECC) in open heart surgery has its origin in disorders of platelet number and function as well as in changes of the haemostatic balance. Not only are the plasmatic factors of the coagulation and the fibrinolytic system of importance but also their inhibitors which tend to avoid dysfunctions and overshooting reactions. To detect early the danger of an excessive bleeding tendency assays of fibrinogen (factor I), prothrombin (factor II), antithrombin III (AT III) and of alpha 2-macroglobulin (A 2 M) are recommended. A substitution therapy can be oriented by the results of these coagulation parameters.

During open heart surgery, needle biopsy material was obtained in four patients, and electron microscopic preparations of the mitochondrial ATPases (coupling factors 1) in human myocardial cells were performed. The pre-ischemic, normal structure of the mitochondrial ATPases and the changes which occur during the ischemic interval were described. An increase in the center-to-center space was shown in the post-ischemic phase. This result was discussed for the pathogenesis of subcellular injuries due to ischemia.