摘要:

In order to test the hypothesis that low‐dose midazolam reduces excitatory cerebral symptoms by attenuating ketamine‐induced increases in the cerebral metabolic rate for oxygen (CMRo2), we compared the cerebral effects of a combination of an anaesthetic dose of ketamine hydrochloride (10.0 mg‐kg1i.v.) and a subanaesthetic dose of midazolam maleate (0.25 mg‐ kg‐1i.v., n = 6; or 0.10 mg‐kg‐1i.v., n = 6) with results recently obtained with ketamine (10.0 mg‐kg‐1i.v.) in normoventilated pigs anaesthetized with fentanyl, nitrous oxide and pancuronium. Cerebral blood flow (CBF) was measured with the intra‐arterial133Xe clearance technique, and CMRo2was calculated from CBF and the cerebral arteriovenous oxygen content difference (Cavo2). The CMRo2did not increase significantly. In contrast, the maximal increase in cerebral Cavo2(by 56–59% at 10 min;P<0.01) was similar to that induced by ketamine, since CBF was more depressed (by 35–45% at 1 min:P<0.001) by ketamine‐midazolam than by ketamine only. Midazolam was found to increase CVR (P<0.01) and further depress CBF (P<0.01), and to antagonize the ketamineinduced increase in CMRo2(P<0.05). Ketamine‐induced effects on mean arterial pressure (MAP) and spectral electroencephalographic (EEG) voltage were not significantly altered by midazolam. The pharmacokinetics of ketamine, as measured during an 80‐min period, were not affected by the concomitant administration of midazolam. We propose that a ketamine‐midazolam combination comprising a low‐dose fraction (1/ 100‐1/40) of midazolam is superior to

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1993.tb03759.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

This is a prospective, open, randomized study comparing three different anaesthetic regimens with respect to haemodynamic stability (cardiac index and pressure measurements), ischaemia (ECG), and loss of awareness (midlatency auditory evoked potentials) in 58 patients undergoing coronary artery surgery. Anaesthesia was based on fentanyl 0.01 mg kg‐1bw for induction and 0.8‐2.0 mg h‐1in combination with nitrous oxide for maintenance before cardiopulmonary bypass and 0.2‐0.6 mg h‐1without nitrous oxide during and after cardiopulmonary bypass. Eighteen patients were anaesthetised with flunitrazepam 0.01 mg kg‐1bw for induction and received thereafter 1–2 mg h‐1for maintenance (group F). In 40 patients anaesthesia was induced with etomidate and maintained with either isoflurane 0.4‐1.2 vol% (group I) or propofol 4–10 mg kg‐1bw h‐1(group P). Vasodilators and inotropes were used for haemodynamic control when needed. Haemodynamic variables and ECG were studied at five timepoints (awake; after induction before surgery; after sternotomy; before cardiopulmonary bypass; and 20 min after separation from bypass). During surgical stimulation, vasodilators were needed significantly more frequently in group F, than in groups I and P. Surgery and sternotomy caused an increase in SVI and APs/SV in all groups. Differences between the groups were only found for systemic pressures, which after sternotomy were lowest in group I and before cardiopulmonary bypass were highest in group F. After termination of bypass all groups showed an increase in HR and a decrease in SVI, SVR, and LVSWI compared to the awake state, while CI remained unchanged. The only differences noted between the groups were a lower PCWP and a smaller reduction in SVR with propofol compared to the others and higher APs/SV with propofol compared to isoflurane. Concerning ST segment changes (>0.1 mV, leads II and/or V5) at the five measurement times, significant differences were found comparing groups F and P after sternotomy (P<0.10) and comparing groups F and I after separation from CPB (P<0.05), group F showing the highest incidences of ischaemic events. A blinded evaluation of auditory evoked potentials demonstrated more reduced midlatency auditory potentials after sternotomy during isoflurane and propofol anaesthesia than during flunitrazepam. The authors conclude that fentanyl supplemented with isoflurane or propofol was unequivocally superior to supplementa

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1993.tb03760.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

In order to evaluate the anticholinergic effect of fentanyl and pethidine, the influence of these drugs on the cumulative dose‐response curves of carbacholine on the guinea‐pig ileum has been investigated. Fentanyl and pethidine displaced the dose‐response curve for carbacholine to the right in a parallel fashion, indicating competitive antagonism. Dissociation constants determined by an agonist EC versus antagonist plot were 0.22 μmol/1 for fentanyl and 1.4 μmol/1 for pethidine. It is concluded that during high‐dose fentanyl anaesthesia, fentanyl may bind to muscarinic receptors and thereby produce a central anticholinergic syndrome. An additional finding was that the maximal response to carbacholine increased significantly when combined with

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1993.tb03761.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Postoperative headache and backpain has limited the use of intrathecal anaesthesia in younger patients (15–45 years). We studied postoperative complaints among 133 healthy young patients (mean age 30.0 years, 47% females) who received spinal anaesthesia with a 27G needle. Postoperatively, 5 patients (4%) complained of postdural puncture headache (PDPH), 18 (14%) reported nonspecific headache, while 27 (20%) suffered from backpain. PDPH was not related to sex, age, day‐care surgery, number of puncture attempts, or obstetric procedures. Backpain was significantly more common among females, and among in‐patients. One hundred and sixteen patients (87%) would accept spinal anaesthesia if they were to undergo the same surgical procedure again. Compared to other studies, we find the incidence of postanaesthetic complaints to be acceptable, also among day‐care patients. The PDPH seemed to be lightly incapacitating, and only one patient required blood p

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1993.tb03762.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Pulmonary structure was analysed by means of computed tomography (CT) in 20 lung‐healthy patients, relating tissue density to the attenuation value (AV) of a picture element. Regional density of pulmonary tissue (rlung) was determined using mean lung density in five regions of interest (ROI1–5) (sector method). Vertical and horizontal distributions of x‐ray attenuation were analysed by density profiles, relating AV values to evenly distributed and normalised length scales. In group I (n= 12), CT‐densitometry was obtained in awake, supine patients and after induction of general anaesthesia. In group II (n = 8), the effect of mechanical ventilation with positive end‐expiratory pressure (PEEP, 1.0 kPa [10 cmH2O]) was studied. In the awake state, a vertical tissue density difference between the top and the bottom of the lung was found in all patients, accounting for a mean of 0.235 g'cm‐3(right lung) and 0.199 g'cm‐3(left lung). Only minor changes were seen in the horizontal lung density profiles. After induction of anaesthesia, x‐ray attenuation of ROI1–4showed no significant differences when compared with the awake state. The basal lung areas (ROI5) revealed a significantly increased tissue density (P≤ 0.01), reaching mean values of 0.94 g cm‐3(right lung) and 0.814 g‐cm‐3(left lung). Similarly, vertical density profiles showed a markedly enhanced rlungof the bottom of the lung in all patients, interpreted as atelectasis. The amount of atelectasis accounted for 4.8 ± 2.6% (right lung) and 4.7 ± 2.1% (left lung) of the intrapulmonary area. There was no evidence of “non‐gravitational” inhomogeneity of density distribution seen in the horizontal density profiles. After application of PEEP, basal lung densities decreased significantly, although small basal densities remained in most patients (2.27 ± 2.57% of right intrapulmonary area [P≤ 0.01], 2.2 ± 2.37% left intrapulmonary area [P≤ 0.01]). Calculated alveolar recruitment was 7.7 cm2and 8.4 cm2, whereas expansion of both lungs was smaller (4.3 cm2and 4.4 cm2[right and left lung]). Mean density of aerated tissue had decreased by 25%, and both horizontal and vertical attenuation profiles revealed an even distribution of rlung. Analysis of rlungprovides useful information about regional pulmonary morphology during anaesthe

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1993.tb03763.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Simple clinical tests, like Romberg's test or a walking test, have proved to be inadequate guidelines for safe discharge after outpatient anaesthesia (1, 2). A randomised study was therefore planned to compare postural stability measured by computerised posturography in 31 oral midazolam‐atropine premedicated children aged 6.9 (s.e. 0.4) years who had been anaesthetised with either propofol/aIfentanil/N2O or thiopentone/ halothane/N2O. The sway velocity of the children was measured before premedication and 1, 2 and 3 h after the end of anaesthesia. Results show that sway velocity had returned to baseline values 3 h after the end of anaesthesia in all children who had received propofoI/alfentanil/N2O and in 12 of the 15 children who had received thiopentone/halothane/N2O. The quantified version of the Romberg test performed with eyes open or closed was not impaired after anaesthesia, compared with the control values, indicating that in children poor equilibrium is not compensated by vision. The clinical recovery with respect to the times to eye opening, to responding to command or to being fully awake did not differ between the two anaesthesia methods. On the basis of recovery assessed by postural stability, propofol/alfentanil/N2O anaesthesia was not preferable to thiopentone/halothane/NsO anaesthesia after minor paediatric otolaryngological surger

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1993.tb03764.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Fifty patients with chronic resistant cervicobrachialgia were randomly divided into two groups. Twenty‐five patients (group A) were treated with cervical epidural steroid/lidocaine injections and 17 patients (group B) were treated with steroid/lidocaine injections into the posterior neck muscles. Another eight patients from group B were excluded from the study because they had started the process of litigation of insurance claims and their subjective analysis of pain relief might therefore not be trustworthy. One to three injections were administered at 2‐week intervals according to the clinical response. All patients continued their various pre‐study treatments: non‐steroidal anti‐inflammatory drugs, non‐opioid analgesics and physiotherapy. Pain relief was evaluated by the visual analogue scale 1 week after the last injection and then 1 year later. One week after the last injection we rated pain relief as very good and good in 76% of the patients in group A, as compared to 35.5% of the patients in group B. One year after the treatment 68% of the group A patients still had very good and good pain relief, whereas only 11.8% of group B patients reported this degree of pain relief. These differences were statistically significant. We failed to achieve significant improvement of tendon reflexes or of sensory loss in both groups, but the increase in the range of motion, the fraction of patients who were able to decrease their daily dose of analgesics, and recovery of the capacity for work were significantly better in group A. We encountered no complications in either group of patients. We conclude that cervical epidural steroid/local anaesthetic injection is an effective method for achieving immediate and long‐standing pain relief and improvement in motion and performance in chronic resistant cervi

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1993.tb03765.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

We implanted closed cranial windows in ten cats in order to observe the response of pial vessel diameter by microscopy using fluorescein isothiocyanate‐labeled dextran and regional cerebral blood flow (rCBF) by laser Doppler flowmetry during administration of midazolam and reversal with flumazenil. Midazolam was given at 0.8 mg.kg‐1min‐1for 10 min and maintained at 0.04 mg‐kg‐1min‐1for 50 min (total 10 mg‐kg‐1). The diameter of arterioles and venules and rCBF showed no significant change. During the last 10 min of midazolam administration, flumazenil, given at 0.1 mg‐kg‐1min‐1for 10 min (total 1 mg kg‐1), caused an increase of MAP and rCBF (P50 μm) and venules (50–100 μ) were dilated (P<0.05). These results indicate that midazolam does not affect the diameter of cerebral arterioles and venules; however, the reversal effects of flumazenil against midazolam are transient vasodilation of larger arterioles accompanied by an elevation of

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1993.tb03766.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

The acute effects of thiopentone on plasma glucose concentration and regulation in humans have not been well described. We therefore examined the effect of a single dose (6 mg/kg) of thiopentone on plasma glucose, insulin, glucagon, adrenaline and noradrenaline in 16 healthy women undergoing elective abdominal surgery. To assess involvement of the neuroendocrine system in the response to thiopentone, half of the patients labetalol prior to induction of anaesthesia. Thiopentone injection resulted in a 50% increase in plasma glucose levels (P<0.001) in both labetalol‐treated and non‐treated patients 90 s following its administration. This was associated neither with significant increases in plasma glucagon, adrenaline and noradrenaline nor with a decline in plasma insulin. We conclude that acute hyperglycaemia following thiopentone is most likely the consequence of a non‐adrenergically‐mediated increase in hepatic glucose

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1993.tb03767.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

It has been presumed that alteration in the concentrations of second messengers leads to alterations in the function of the ryanodine receptor. Consequently, we have determined the basal content of cyclic AMP and inositol phosphates in skeletal and cardiac muscle of malignant hyperthermia (MH) susceptible (MHS) and healthy normal control (MHN) swine. Since α,‐ and β‐adrenoceptors are linked to these second messenger systems, the densities of α1,‐ and β‐adrenoceptors were also determined. In skeletal as well as cardiac muscle, a higher basal concentration of almost all of the inositol phosphates was found. Of all inositol phosphates measured, the presumed second messenger inositol 1,4,5‐trisphosphate (1,4,5‐IP3) was mostly concentrated in both tissues. Each MHS sample contained more 1,4,5,‐IP3 than the highest value observed in MHN muscle, indicating that a threshold of 1,4,5‐IP3 concentration for determination of MHS or MHN status can be defined. In addition, MHS skeletal muscle contained more cAMP than MHN, whereas there was no difference between MHS and MHN in cardiac muscle. The changes observed in the different inositol phosphate and cAMP contents were not accompanied by an altered α1,‐ or β‐adrenoceptor density in skeletal or cardiac muscle between MHS and MHN. However, the total number of β‐adrenoceptors of MHN and MHS was significantly higher in cardiac (about 80 fmol/mg protein) than skeletal muscles (about 30 fmol/ mg protein). The cardiac muscles revealed about 80% β1,‐ and 20% β2‐adrenoceptors, whereas skeletal muscles were characterised by over 95% β2‐adrenoceptors. In conclusion, the present study supports the view that altered second messenger systems and, thereby, altered intracellular calcium regulations are at least in part involved in the modulation and development of MH. Moreover, in addition to the skeletal muscle, multiple other orga

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1993.tb03768.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY