| Autor: |
D, Patschke, J B, Brückner, J W, Gethmann, J, Tarnow, A, Weymar |
| Jazyk: |
němčina |
| Rok vydání: |
1975 |
| Předmět: |
|
| Zdroj: |
Praktische Anasthesie, Wiederbelebung und Intensivtherapie. 10(6) |
| ISSN: |
0302-7600 |
| Popis: |
Ketamine is an induction agent. This experimental study was designed to investigate the immediate effects of ketamine upon haemodynamics, inotropism and myocardial oxygen consumption during induction. In a circulatory steady state of a piritramide - nitrous oxide - oxygen basic anaesthesia normoventilated dogs (n = 8) received intravenous injections of 5.0 and 10.0 mg/kg ketamine within 30 sec at random. Immediately after administration of 10.0 mg/kg ketamine the cardiac output (thermo dilution method) rose (27%) on account of tachycardia while the total peripheral resistance (40%) and the mean arterial pressure (23%) decreased. The decrease in stroke volume (37%) and the inotropic parameter dp/dt max (42%) as well as the increase in the end-diastolic left ventricular pressure (31%) and in the pressure of the pulmonary artery (11%) suggest considerable myocardial depressor properties of ketamine. The change in haemodynamics was paralleled with an increase in myocardial oxygen consumption (47%), which was initially met by an increase in coronary blood flow (25%) and an additional oxygen utilization (20%). The increase in arterio-coronary venous oxygen difference is believed to be due to a constriction of the coronary arteries after ketamine. Since external cardiac work remained unchanged,while myocardial contractility and myocardial wall tension (Psyst) decreased, the increase in heart rate (63%) explains the rise in myocardial oxygen consumption. The efficiency of cardiac work, which is defined as the ratio of myocardial displacement work to myocardial energy demand, decreased (31%) and illustrated the uneconomic work of the heart under the influence of ketamine. The clinical utilization of the data obtained from this study are discussed. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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