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The effects of dihydroergotamine (DHE) on the circulation of the leg during combined epidural and general anaesthesia were studied to determine if DHE would enhance leg blood flow and prevent postoperative deep vein thrombosis in a double-blind trial of 40 elderly female patients subjected to cholecystectomy. Central and big toe temperature, arterial blood pressure, heart rate, calf volume and arterial inflow of the leg by electrical impedance plethysmography and the venous outflow by Doppler method were measured. DHE 0.5 mg subcutaneously reduced the volume of the leg, i.e. increased the electrical impedance, probably due to venous vasoconstriction. Simultaneously the need for etilefrine hydrochloride was reduced. No significant changes in the pulsatile inflow of the leg or the outflow were detected. Deep vein thrombosis (DVT) was detected by fibrinogen uptake test in five patients (three in DHEH and two in the control group) and verified by ascending phlebography in four patients. Intraoperative characteristics in patients with postoperative DVT were tachycardia (P < 0.001), enhanced need for etilefrine (P < 0.01) and a more rapid increase in big toe temperature (P < 0.05) after induction of epidural analgesia, compared with patients without DVT. Femoral vein flow velocity remained at the preinduction level, whereas pulsatile arterial inflow slightly increased. Together with a low basal impendance of the leg, the changes were indicative of a more intense vasodilatation, probably leading to stagnant flow and development of postoperative deep vein thrombosis.

Sixty female patients were given, in random order, under double-blind conditions, either midazolam or fat-emulsion diazepam, intramuscularly, as premedication, 1 h before general anaesthesia. The dose of midazolam used was 0.13 mg/kg and that of diazepam 0.17 mg/kg. The degree of sedation, mood of the patient, and time at which onset of effect was perceptible were assessed before induction of anaesthesia, together with skin temperature and concentrations of midazolam or diazepam in plasma. Patients were interviewed postoperatively to discover their subjective evaluation of the premedication and to assess its amnesic effects. Midazolam was significantly superior (P less than 0.05) to diazepam as regards sedation. There were no differences in effects on mood of the patients between the two groups. Sixteen patients in the diazepam group and four in the midazolam group had no perception of onset of effect. The difference is significant (P less than 0.01). The skin temperature was, on average, 2 degrees C higher in the midazolam group than in the diazepam group (P less than 0.005). The mean plasma concentration was 67.8 +/- 24.5 micrograms/l in the midazolam group and 44.8 +/- 25.7 micrograms/l in the diazepam group. In only two cases was the concentration of diazepam above 100 micrograms/l (arbitrarily defined as the minimum sedative concentration). Subjective evaluation of efficacy significantly (P less than 0.002) favoured midazolam. Local pain was evident in two patients in the diazepam group, and three patients experienced nausea immediately after administration of the drug.(ABSTRACT TRUNCATED AT 250 WORDS)

Xylitol has been suggested as a more advantageous calory source for intravenous administration than glucose in certain clinical situation, but the general suitability of intravenous xylitol infusion has not been confirmed. Thirty-middle-aged women were infused with 100 g of xylitol as postoperative fluid therapy after gynaecological laparotomy and general anaesthesia. Another 10 women received 50 g of glucose in a similar manner and served as a reference group. Infusion of xylitol both at the rate of 0.25 g/kg/h (1000 ml 10% xylitol in approx. 8 h) and 0.5 g/kg/h (1000 ml 10% xylitol in approx. 4 h) caused a distinct increase in the serum concentrations of lactic acid, pyruvic acid, and uric acid; such an increase was not seen with glucose infusion. The faster infusion of xylitol also distinctly increased serum bilirubin concentrations. Because of the possibility of lactic acidosis and urate deposits in kidneys, infusion of 100 g or more of xylitol at a rate of 0.25 g/kg/h or faster is not safe for postoperative fluid therapy in routine clinical work.

Two preparations of diazepam, Valium Roche mixed Micelles and Diazemuls, were compared as intravenous premedicants in 119 patients undergoing minor gynaecological surgery. There were no differences between the formulations with regard to anxiolytic effects and systemic tolerance. There were no symptoms typical of thrombophlebitis in the Valium Roche Mixed-Micelles group and only one case in the Diazemuls group. Acute local tolerance was similar with both trial drugs and superior to conventional diazepam preparations. Based on the favourable results of the present study it can be concluded that such vehicles should be considered for any injectable preparation with a known tendency to produce venous irritation.