Der Anaesthesist
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Protamine is a strongly alkaline polypeptide with a molecular weight of about 4500. Protamine solutions contain paraben compounds as antimicrobial agents. Rapid neutralization of heparin by protamine may cause an anaphylactoid reaction characterized by a non-immunogenic histamine release and by unknown mediators mechanisms. ⋯ The pronounced activation of polymorphonuclear leukocytes and the decrease in platelet counts may reflect a mere epiphenomenon. The degree of right ventricular afterload increase at which systemic hypotension requiring immediate therapy would occur depends mainly on the contractile state of the heart. Potential risk patients for severe protamine reactions are depot insulin-dependent diabetics and patients with prior exposure to protamine.
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Randomized Controlled Trial Clinical Trial
[Recombinant erythropoietin in autologous blood donation].
As a result of the AIDS crisis, public and physician pressure have increased the utilization of autologous blood products. Attitudes about homologous blood transfusion, however, have changed dramatically in recent years. A large segment of the population undergoing elective surgery is elderly and therefore has a significant incidence of cardiovascular disease and a slow response of the erythropoietic system when acute anemia occurs. ⋯ As a consequence, patients with anemia and particular contraindications to homologous blood derivatives (irregular antibodies, Jehovah's Witnesses) may be able to undergo major surgery successfully. The possibility of shortening the intervals between phlebotomies would seem to be of major advantage; our data also suggest that an aggressive autologous blood collection program would increase yields over present programs. In our institute a minimum hemoglobin level of 11.5 g/dl is accepted for autologous donation.(ABSTRACT TRUNCATED AT 400 WORDS)
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For major operative procedures in the lower abdomen and many orthopedic procedures such as total hip replacement, a combination of general and epidural anesthesia is used. In order to investigate the hemodynamic effects of such a combination in 14 geriatric patients aged 63-80 years who were undergoing total hip replacement, cardiovascular monitoring was established by an arterial line and a pulmonary artery catheter. The epidural anesthesia was achieved with bupivacaine 0.5% in a dose calculated to obtain a block up to Th 6. ⋯ Oxygen delivery and oxygen extraction did not change. During general anesthesia a significant drop in cardiac output was observed from 3.0 +/- 0.6 l/min.m2 to 2.3 +/- 0.4 l/min.m2 (p less than 0.05). The systolic arterial blood pressure decreased to as low as 95 +/- 17 mmHg (p less than 0.05) and oxygen delivery decreased from 500 +/- 125 ml/min.m2 to 323 +/- 84 ml/min.m2 (p less than 0.05).
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The aim of the present study was to introduce a new method of external selective brain cooling in cats. By means of this device, which mainly consisted of a head-sized, closely fitting copper basin, it was possible to reduce brain temperature rapidly. The resultant difference between core and cerebral temperatures amounted to mean values of about 10 degrees C after a 20-min cooling period. ⋯ The clinical data obtained indicate that the described method provides a means for efficient heat exchange from within the intracranial space. Rapid, selective brain cooling could be achieved without any critical reduction of the core temperature and therefore, cardiac arrhythmias, a usual consequence of generalized hypothermia, could be avoided. The histopathological evaluation of ischemic neuronal damage showed a significantly higher percentage of unaffected cells in some areas of the cerebral cortex in animals treated with postischemic cerebral hypothermia than in the controls.(ABSTRACT TRUNCATED AT 250 WORDS)
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Anesthetic management of patients presenting for posterior cranial fossa surgery in the seated position includes detection and treatment of venous air embolism. Atrial positioning of a central venous (cv) line may be verified by either X-ray or an atrial ECG tracing. We report a case where a chest X-ray film proved superior. ⋯ Subsequent cardiologic and radiologic examinations revealed a patent foramen ovale and a persisting left superior vena cava draining into a dilated coronary sinus. Surgery was rescheduled and carried out uneventfully in the prone position. This case demonstrates: 1) an advantage of a thoracic-X-ray film compared to atrial ECG tracing as not only the catheter tip position, but also the course of the catheter can be identified; and 2) the usefulness of preoperative screening for a patent foramen ovale in patients scheduled for surgery in the seated position.