Der Anaesthesist
-
Randomized Controlled Trial Comparative Study Clinical Trial
[Heat and moisture exchangers for conditioning of inspired air of intubated patients in intensive care. The humidification properties of passive air exchangers under clinical conditions].
Heat and moisture exchangers (HME) are used as artificial noses for intubated patients to prevent tracheo-bronchial or pulmonary damage resulting from dry and cold inspired gases. HME are mounted directly on the tracheal tube, where they collect a large fraction of the heat and moisture of the expired air, adding this to the subsequent inspired breath. The effective performance depends on the water-retention capacity of the HME: the amount of water added to the inspired gas cannot exceed the stored water uptake of the previous breath. ⋯ These data are simple to obtain without affecting the patient and can easily be interpreted. It was demonstrated that, compared to physiological conditions, the DAR Hygrobac and Gibeck Humid Vent 2P-HME coated with hygroscopic salts-were able to maintain sufficient inspiratory humidity and heat. The Pall-HME, solely a condensation humidifier, did not meet the physiological requirements.
-
Randomized Controlled Trial Clinical Trial
[CO2 stores in laparoscopic cholecystectomy with CO2 pneumoperitoneum].
Two groups of 22 patients each were studied in a prospective, randomised fashion during laparoscopic cholecystectomy (LCh) and CO2 pneumoperitoneum (PP) with regard to end-tidal and arterial PCO2 and pulmonary elimination of CO2 (ECO2, Servoventilator with integrated CO2-analyser 930, Siemens). In group 1 minute ventilation was kept constant, resulting in moderate hypercapnia during PP. paCO2 increased by about 10 mmHg during up to 50 min PP. In group 2 paCO2 was kept constant by a stepwise increase in minute ventilation (Fig. 1, Table 2). ⋯ Assuming a stable metabolic CO2 production rate during the observation period and no differences in CO2 absorption from the PP between the two study groups, differences in ECO2 between groups would be a measure of CO2 stored in group 1 patients during the increase in paCO2 with PP (Fig. 3, Table 3). CO2 storage rapidly increased between 0 and 15 min PP, more or less reached a plateau between 15 and 35 min PP, and ceased at 45 min PP. Storing capacity for CO2 during the first 45 min PP amounted to a mean value of 1.20 ml CO2/kg body weight and mmHg paCO2, which agrees favourably with data from the literature and a computer model from Fahri and Rahn published in 1960 (Fig. 4, Table 4). If during LCh with CO2-PP patients are ventilated with a constant minute ventilation, a moderate increase in paCO2 of about 10 mm Hg can be expected. In this case, during the first 45 min PP a 70-kg patient will retain about 1000 ml CO2 in blood and tissues, which must be eliminated after cessation of PP. If the paCO2 is to be held constant during PP, minute ventilation has to be progressively increased by about 40%.
-
Randomized Controlled Trial Comparative Study Clinical Trial
[Intravenous anesthesia with propofol versus thiopental-/enflurane anesthesia. A consumption and cost analysis].
It may be possible to reduce costs in anaesthesia when there is a choice of drugs and methods. Two of the most widespread techniques are inhalation anaesthesia with enflurane following induction with thiopentone, and intravenous anaesthesia (IVA) with propofol. The aims of our study were to compare the costs, effectiveness and side effects of the anaesthetics involved in these two techniques, and to measure significant clinical parameters. ⋯ Minute ventilation, oxygen consumption, heart rate and CO2 production indicated a less pronounced stress response and sympathetic activity during and after propofol. Quicker recovery of cognitive and psychomotor abilities, less postoperative pain and less impairment of respiratory function after IVA may lead to an earlier release from the postoperative recovery unit. This might be a cost-reducing factor that should be taken into account when these two anaesthetic regimens are concerned.
-
Randomized Controlled Trial Comparative Study Clinical Trial Controlled Clinical Trial
[Prevention of myocardial ischemia. Study following aortocoronary bypass operation with the calcium antagonist diltiazem].
The incidence of postoperative myocardial infarction (MI) is proportional to the incidence of myocardial ischaemic episodes. Therefore, the prevention of such episodes is of great clinical importance. METHODS. ⋯ DIL results in marked haemodynamic stabilisation during CABG, especially in the period immediately after extra-corporeal circulation. This might serve as an explanation for the significant reduction in ischaemic episodes in the DIL group compared to the other two groups. Therefore, perioperative prevention of myocardial ischaemia with the calcium antagonist DIL seems to be favourable in patients during CABG.
-
Randomized Controlled Trial Comparative Study Clinical Trial
[Psychometric changes as well as analgesic action and cardiovascular adverse effects of ketamine racemate versus s-(+)-ketamine in subanesthetic doses].
The intravenous anaesthetic ketamine is widely used in subanaesthetic doses as a potent analgesic in emergency and disaster medicine. At present, ketamine is commercially available only in its racemic form, although the S(+)-isomer has proved to be approximately three times as potent than the R(-)-isomer. In first clinical trials in Germany, S(+)-ketamine was reported to be markedly advantageous with regard to analgesia in anaesthetized patients. ⋯ S(+)-Ketamine at half-dose of ketamine-racemate is as potent as ketamine-racemate in subanaesthetic doses with powerful analgesic properties. The (+)-isomer exerts less adverse effects on measurable cerebral functions and induces a significantly smaller increase in heart rate. Since states of impaired consciousness and disorientation are especially disturbing under emergency conditions, further investigations should be carried out to define S(+)-ketamine's position as a potent analgesic for therapeutic use in emergency and disaster medicine.