Rat myocardial tissue lipids and their effect on ventricular electrical activity: influence on dietary lipids.

OBJECTIVE: The aim was to investigate the effect of diets with different lipid content on rat myocardial tissue lipid composition and their possible influence on myocardial electrical activity. METHODS: 60 male Sprague-Dawley rats were randomised in three dietary feeding groups. Half the animals were used for the myocardial lipid study and the other half for the ventricular refractory period and ventricular conduction velocity measurements. Synthetic diets of low fat, high fat (predominantly lard fat), and high fat plus marine oil, the last two with cholesterol, were supplied ad libitum for five weeks. After 2-propanol myocardial lipid extraction, lipid fractions were separated by thin layer chromatography and their esterified fatty acids by gas-liquid chromatography. Ventricular refractory period was obtained according to the extrastimulus technique and maximum conduction velocity by ventricular pacing. RESULTS: The experimental diets induced marked changes in fatty acid composition of myocardial phospholipids and in esterified cholesterol content. The high fat group showed a significant decrement in oleic and linoleic acids, with an increment in arachidonic and docosahexaenoic acids in their phospholipid composition. This dietary group had the highest esterified cholesterol content. These changes were related to lowering of maximum ventricular paced heart rate and lengthening of ventricular refractory period, and were partly corrected by marine oil supplement. CONCLUSIONS: Saturated fat diets cause profound changes in myocardial fatty acyl composition which are linked to sustained differences in myocardial electrical activity. These changes can be partly corrected by a moderate fish oil supplement.

[Intraoperative autotransfusion in massive hemorrhage following thoracic-abdominal trauma]. / Intraoperative Autotransfusion bei Massivblutungen nach Thorax-Bauch-Traumen.

In the University Hospital of Granada (Spain), 359 surgical trauma patients underwent intraoperative autotransfusion. The patients were divided into 2 groups, according to their blood loss: group I (blood loss less than or equal to 2000 ml) and group II (blood loss greater than 2000 ml). Patients from group I did not require homologous blood transfusion. So the high risk involved in this type of transfusion was avoided. Macroscopic haemoglobinuria was only found in those patients where the Solcotrans, Viavae type of autotransfusion system was used; with the Bentley ATS system, no macroscopic haemoglobinuria was registered. With patients from group II, however, that is, those with a blood loss of more than 2000 ml, we had to fall back on homologous transfusion in addition to retransfusing autologous blood. When the transfusion exceeds 4000 ml there is increasing bleeding, which requires treatment with fresh frozen plasma, platelets and/or fibrinogen. The mortality rate of patients in group II was very high but the patients died from the severity of their injuries or from postoperative complications which were not due to autotransfusion in itself with the exception of 3 patients who underwent massive autotransfusion (12,000 to 25,000 ml) and died from acute renal failure. The main indication for intraoperative autotransfusion is without doubt abdominal and thoracic trauma which lead to high blood loss.