Der Anaesthesist
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Randomized Controlled Trial Comparative Study Clinical Trial
[Cardiovascular effects after bolus administration of cisatracurium. A comparison with vecuronium].
Cisatracurium-one of the ten stereoisomers of atracurium-is an intermediate long-acting non-depolarizing neuromuscular blocking agent. Cardiovascular reactions have been described after administration of cisatracurium or vecuronium in surgical patients. ⋯ After the administration of cisatracurium in two different doses (3xED95 and 5xED95) or vecuronium (3xED90) only minor cardiovascular changes were observed. Both drugs proved to be safe for use during induction of anaesthesia in patients ASA I-II. With regard to its cardiovascular effects, cisatracurium shares with vecuronium the requirements of an ideal muscle relaxant.
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Randomized Controlled Trial Comparative Study Clinical Trial
[The effect of convection warming during abdominal surgery on the early postoperative heat balance].
Hypothermia (core temperature < 36 degrees C) is common after longer-lasting surgical procedures. Heat loss mainly occurs during anaesthesia and surgery and leads to increased risk, especially in the early recovery period of elderly patients. In the present study we investigated the effects of intraoperative forced-air warming, administered via an upper-body blanket ("Warm Touch", Mallinckrodt, USA), with the specific aims of: (1) drawing up heat balances; and (2) analysing postoperative thermoregulation, oxygen consumption (VO2) and cardiovascular reactions of mechanically ventilated patients. The general aim of our study was to compare intraoperative forced-air-warming and conventional patient-insulation with cotton blankets. ⋯ Both groups were comparable for gender, body weight, height, age, duration of their operations and amount of intraoperative fluids, narcotics and muscle relaxants. Room temperatures in the control group were significantly higher than in the forced air group (24 vs 22 degrees C). Initial setting of the forced-air blower was "high" (42-46 degrees high air flow). When the oesophageal-temperature reached 36.5 degrees C, the blower temperature was reduced to 36-40 degrees C. Reduction was necessary approximately 60 min from start in the operation. At the end of surgery/administration to the ICU core-temperatures of both groups differed significantly (35.2/ 35.4 degrees C vs 36.3/36.2 degrees C). Mean-skin temperatures were higher, too, but no statistical analysis was carried out for the intraoperative period, because warm air influenced skin thermometers located on the upper body. At admission to the ICU patients in the control group had a heat loss of 4.4 kJ/kg; those in the convective warming group had a heat-gain of 0.8 kJ/kg. Further measurements of postoperative core temperatures did not differ significantly, but the skin-temperatures of patients who received forced-air warming in the theatre remained higher (P < 0.05) until 120 min from the end of surgery. Shivering was more frequent and lasted longer in the control group (8 patients, 20 min vs 4 patients, 9 min; P < 0.05). Patients in the control group needed more drugs to stop increased cardiovascular reactions (hypertension, tachycardia) or shivering.(ABSTRACT TRUNCATED)
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Randomized Controlled Trial Clinical Trial
[Propofol and etomidate-Lipuro for induction of general anesthesia. Hemodynamics, vascular compatibility, subjective findings and postoperative nausea].
Etomidate has become an important induction agent in high-risk patients because of its cardiovascular stability. Its unwanted side-effects such as pain on injection and thrombophlebitis could be significantly reduced by a new (medium chain triglyceride and soya bean) emulsion formulation. Propofol is solved in a mixture of long chain triglyceride and soya bean emulsion. In this double-blind, randomized study we compared the haemodynamic effects, the patients' sensations, signs of thrombophlebitis and postoperative nausea and vomiting (PONV) following injection of both drugs. ⋯ Etomidate formulated in a medium chain lipid emulsion causes significant less discomfort for the patients than propofol, which is solved in a long chain formulation. Myocloni, however, occur significantly more frequently after etomidate than after propofol.
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Randomized Controlled Trial Clinical Trial
[The effect of nitroglycerin on cerebrovascular circulation, cerebrovascular CO2-reactivity and blood flow rate in basal cerebral arteries].
The cerebral haemodynamic effects of vasodilators are of clinical interest because a decrease in mean arterial pressure (MAP) might alter global cerebral blood flow (CBF). Luxury perfusion of the brain, contrast, might be unfavourable in patients with reduced intracranial compliance. Despite the widespread use of nitroglycerine (NTG), little is known about the cerebral haemodynamic consequence of NTG infusions in humans. This prospective, controlled study was designed: (1) to investigate the effects of NTG on CBF and cerebrovascular CO2 reactivity and (2) to compare reference measurements of global CBF with transcranial Doppler monitoring (TCD) of middle cerebral artery flow velocity (VMCA). ⋯ This study demonstrates that during fentanyl/midazolam anaesthesia NTG may cause a major increase in CBF as long as CPP does not decrease considerably. Our results further suggest that NTG causes vasodilation of basal cerebral arteries, inducing a discrepancy between relative changes in CBF and VMCA. Consequently, TCD measurements during infusion of NTG should not be directly compared with preceding measurements of MCA flow velocity.
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Randomized Controlled Trial Clinical Trial
[Variation in inspiratory gas flow in pressure support ventilation. The effect on respiratory mechanics and respiratory work].
During pressure support ventilation (PSV), the timing of the breathing cycle is mainly controlled by the patient. Therefore, the delivered flow pattern during PSV might be better synchronised with the patient's demands than during volume-assisted ventilation. In several modern ventilators, inspiration is terminated when the inspiratory flow decreases to 25% of the initial peak value. However, this timing algorithm might cause premature inspiration termination if the initial peak flow is high. This could result not only in an increased risk of dyssynchronization between the patient and the ventilator, but also in reduced ventilatory support. On the other hand, a decreased peak flow might inappropriately increase the patient's inspiratory effort. The aim of our study was to evaluate the influence of the variation of the initial peak-flow rate during PSV on respiratory pattern and mechanical work of breathing. ⋯ COPD patients had significantly higher pressure support than control patients. With decreasing inspiratory flow, Wpi increased significantly in COPD patients.(ABSTRACT TRUNCATED)