摘要:

Atrial pacing was used for preoperative evaluation of six patients with recent anterior myocardial infarction (MI) (e.g. within 6 weeks) scheduled for abdominal emergency surgery. Central and coronary haemodynamics were used to compare changes in myocardial work and oxygenation with alternations of the non‐invasive variables rate pressure product (RPP) (systolic blood pressure X heart rate), triple product (TP) (systolic blood pressure X heart rate X mean pulmonary arteriolar occlusion pressure) and ST‐T‐segments (lead V5).There was good correlation between myocardial oxygen consumption and rate pressure product and triple product during pacing to stable angina pectoris. ST‐T‐segment depressions were recorded already at moderate chest discomfort and correlated well with a decrease in coronary vascular resistance. Changes in myocardial oxygen consumption induced by combined thoracic epidural analgesia (T3–4 to L1–2) and light general anaesthesia with nitrous oxide and fentanyl were poorly correlated with changes in rate pressure product or triple product. ST‐T‐segment depressions were recorded on five occasions in four of the patients, all in association with intubation and/or extubation. Only on one of these occasions could RPP or TP have indicated that myocardial oxygen demand exceeded supply. On the other four occasions, it was probable that myocardial ischaemia was induced by transient arterial hypoxaemia. The V5 ST‐T‐segment was the most sensitive non‐invasive variable to monitor. The anaesthetic method was safe in all patients, asjudged by good intraoperative cardiovascular stability, low morbidity and absence of intra‐ or p

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1981.tb01656.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

Water humidity and temperature were measured in the proximal end of the inspiratory limb in anaesthetic circuits used to anaesthetize three groups of adult patients using various fresh gas flows (FGF). Humidity increased as FGF's were lowered, with 98% water humidification achieved when FGF's of less than 0.5 1/min were administered. Temperature at the same site changed about 1–2.5d̀C in inverse proportion to the volume of FGF. This advantage of closed system and low flow anaesthesia is a further reason for their wide‐spread utiliza

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1981.tb01657.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

The ability of enflurane and halothane to absorb infra‐red (IR) energy was used to visualize their vapours; IR radiation was emitted by a heated screen and the absorption was studied with an IR camera. Even small concentrations of enflurane (0.2 vol%) and halothane (0.5 vol%) could be detected when released into the operating room atmosphere. Enflurane and nitrous oxide were dispersed in a similar way when they leaked from the face mask. Thus when anaesthetic pollution is monitored in the operating room, measurements of the concentration of nitrous oxide are sufficient for routine purposes. The IR method has added a new dimension to the study of occupational exposure to otherwise invisible gase

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1981.tb01658.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

Pentoxifylline 0.3–30 mg/kg was given intravenously to six dogs under nitrous oxide anesthesia. Cerebral blood flow was measured with a sagittal sinus outflow technique, cerebral oxygen consumption was calculated from the a‐v difference, and metabolite levels were determined in biopsies of cerebral cortex. Pentoxifylline failed to influence cerebral blood flow or oxygen consumption. There was no increase in cerebral levels of phosphocreatine, ATP or total adenine nucleotides; the only significant effect was higher glucose levels in dogs given pentoxifylline (4.49±0.39μmol/g vs 2.21 ±0.18 μmol/g). The latter has previously been reported to be deleterious during cerebral ischemia. Pentoxifylline thus failed to have any significant influence upon cerebral blood flow or metabolism in the dog likely to be of benefit during cerebral hypoxia or i

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1981.tb01659.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

Patients undergoing surgery under regional anaesthesia often receive narcotic analgesics for premedication which may modify the sedative and amnesic effects of intravenously administered diazepam. Sixty‐two patients scheduled for upper extremity surgery under intravenous regional anaesthesia received 0.15 mg/kg of diazepam intravenously to supplement the local anaesthesia. Thirty‐two of the patients received 0.01 mg/kg of atropine plus 1 mg/kg of pethidine and 30 patients only atropine intramuscularly approximately 1 h before the injection of diazepam. Another 30 patients received the same atropine‐pethidine premedication and saline intravenously, and served as a reference group. Atropine‐pethidine premedication followed by saline did not produce any amnesic effects. Sixty‐nine and 38% of patients receiving atropine‐pethidine premedication followed by diazepam did not remember a picture shown to them 15 min after diazepam injection or the performance of operation, respectively, the respective figures for patients given atropine premedication followed by diazepam being only 23% and 0% (P<0.01 ‐ 0.001 between groups). The anti‐recall of painful stimulus (exanguination) was significantly (P<0.01) more common when diazepam was given after pethidine premedication (31%) when compared to its injection after atropine alone (7 %). The drowsiness produced by the drugs was greatest and the overall patient acceptability of the technique used most satisfactory when pethidine was used for premedication and diazepam for sedation. It is concluded that intramuscularly administered pethidine potentiates the amnesic action of intravenous diazepam for painful stimuli, prolongs the amnesic action of diazepam for visual stimuli and improves the patients' acceptability of intravenous regional anaesthesia supplemented by intra

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1981.tb01660.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

Dopamine is widely used in the treatment of hypotensive conditions and/or impending renal failure, but the plasma levels of dopamine and other catecholamines in association with dopamine infusion are not known. Plasma catecholamines and dopamine pharmacokinetics during and after dopamine infusion were therefore studied in man. Two and 5 μg ‐ kg‐1‐ min‐1of dopamine were infused for 30 min in two groups of five patients. Dose‐dependent mean steady state levels with fairly large interindividual variations were reached within 5 min. Elimination of dopamine from plasma after termination of infusion had a biphasic course with t 1/2 around 1 min and t 1/2 β about 9 min in both groups. Noradrenaline plasma levels and blood pressure increased significantly in the 5 μg group. It is suggested that the vasoconstriction with deleterious effects on tissue perfusion, seen in conjunction with high‐dose dopamine infusion, may be due to increased noradr

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1981.tb01661.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

In 40 comatose patients with severe head injury, cerebral blood flow (CBF) studies were performed with the133Xenon washout technique over the most severely injured hemisphere. All patients were mildly sedated with diazepam, chlorpromazine and meperidine and subjected to respiratory support. Simultaneously with the CBF study, intraventricular pressure (IVP), systemic arterial pressure (SAP) and ventricular fluid (VF) lactate, pyruvate and pH were measured. The results indicate a positive correlation between CBF and lactate in patients with a good recovery, irrespective of the time after the trauma, and a positive correlation irrespective of outcome, if the measurements were performed more than 3 days after the trauma. In patients with mainly supratentorial lesions without signs of brain‐stem lesions, CBF and CPP were positively correlated, while CBF and ICP were negatively correlated (lost autoregulation). In contradistinction, CBF was positively correlated to ICP and Paco2in patients with diffuse brain injury. In some cases of repeated dynamic studies, the clinical course seemed to be related to changes in the measured parameter

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1981.tb01662.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

Stimulation of the hypothalamic defence area and activation of somatic afferents in combination with carotid baroreceptor unloading was performed in cats anesthetized with fentanyl‐nitrous oxide in order to investigate the circulatory consequences in terms of regional blood flow changes. These stimulation procedures, suggested to mimic activation of central neurogenic cardiovascular control mechanisms caused by anesthesia and surgical stress, were found to induce pronounced reductions in intestinal and renal blood flow as well as in diuresis. However, administration of droperidol markedly diminished the renal vasoconstriction as well as the reduction in diuresis in the dose range 0.025–0.10 mg/kg b.w. Doses of 0.15–0.25 mg/kg b.w. virtually abolished any stimulation‐induced increase in renal vascular resistance, whether elicited through activation of the defence area or somatic afferents. This dose also partly blocked the neurogenic increment of intestinal vascular res

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1981.tb01663.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

The effects of varying ventilations (Ve) and fresh gas flows (FGF) on end‐expiratory CO2(Feco2) levels were investigated in an experimental model lung, employing the Hafnia modification of the Mapleson A and D anaesthetic systems during CO2‐absorption and CO2‐wash‐out (rebreathing). Identical results were found in both systems: Feco2was constant and independent of FGF with CO2‐absorption and constant Ve, whereas rebreathing resulted in increasing Feco2levels as FGF was decreased. As control of Feco2in the rebreathing systems by regulating FGF could only take place within Feco2levels higher than that determined by Veat complete CO2‐absorption, e. g. for the Hafnia A and D rebreathing systems, control of FGF necessitates relative hyperventilation. Feco2with constant FGF decreased with increasing Veduring CO2‐absorption, as well as during rebreathing, although this decrease was less in the rebreathing systems. Thus a decrease in Feco2with rising Vecan be avoided and hypocapnia prevented. The results agree with those obtained in cli

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1981.tb01664.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

Cats were used to assess the significance of differences in animal preparations in the study of anesthetic‐induced analgesia. Comparison was made between pentobarbital‐anesthetized and decerebrate non‐anesthetized cats. Bradykinin dissolved in normal saline was injected into the femoral artery as a noxious stimulus, and the neural response in the spinal cord lateral funiculus was recorded using the multi‐unit activity technique. The magnitude of the neural response and the changes in spontaneous firing were compared before and after cervical cord transection at C1. Before the transection, the response was greater in anesthetized than in decerebrate cats. The cord transection potentiated the response in both preparations, but the degree of potentiation was greater in decerebrate than in anesthetized cats.These studies confirmed the presence of a descending pain inhibition system acting tonically on the nociceptive neural mechanisms in the spinal cord, and indicated the susceptibility of this system to pentobarbital. We conclude that pretreatment with pentobarbital induces pharmacologically a state of partial spinal cord transection and reduces the effects of drugs acting through supraspinal CNS str

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1981.tb01665.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY