摘要:

The literature concerning the interactions between volatile anaesthetics, nitrous oxide and other compounds is reviewed. The majority are well known and most can be managed by careful dosage of the anaesthetics. The following interactions should be stressed since these are less predictable or potentially fatal. Of the cardiovascular drugs mainly the Ca+ + channel blockers require attention. The volatile anaesthetics act synergistically with these drugs on the inhibition of cardiac conduction and may induce cardiac arrest. Aminoglycoside therapy should prompt an alternative to enflurane because of increased nephrotoxicity with this combination. Thiopentone induction makes the dog heart more susceptible to arrhythmias, especially during anaesthesia with volatile anaesthetics. Probably pentobarbitone, etomidate or a benzodiazepine should be preferred as an alternative to thiopentone when the use of adrenergic drugs peroperatively is anticipated. Nitrous oxide augments the sequelae after coronary air emboli and impaired cerebral perfusion in animals. The necessity of this drug should therefore be considered when anaesthetizing patients undergoing open heart surgery and patients with severe carotic or cerebral arteriosclerosis.

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1993.tb03707.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Major surgery evokes an endocrine stress response, characterized by increased serum cortisol, plasma adrenaline and noradrenaline. Furthermore, surgical stress is accompanied by lymphopenia and granulocytosis in peripheral blood. The changes in peripheral white blood cells have been demonstrated after surgery asiwell as after cortisol infusion. The aim of the present study was to investigate to which tissueslorgans peripheral blood lymphocytes are redistributed after major surgery. From 20 rabbits lymphocytes were isolated from peripheral blood, labelled with indium‐ 111‐tropolene and reinjected intravenously into the rabbits. Ten of the rabbits underwent major surgery (upper laparatomy) during general anaesthesia, while the control group (n= 10) was anaesthetized without surgery. The endocrine stress response to surgery was measured as serum cortisol, plasma adrenaline and noradrenaline. The redistribution of lymphocytes was imaged with a gamma camera and calculated with a connected computer before, 2, 4 and 7 h after the skin incision. Compared to preoperative values, laparotomy resulted in an increase in serum cortisol from 116.6 to 461.9 nmol/l (mean) and a decrease in the fraction/percentage of lymphocytes in peripheral blood from 43.8% to 14.7% 7 h after surgery. Simultaneously, the activity of the heart and lungs together decreased to 76.1% of initial values, while the spleen activity was unaffected. The radioactivity of the lymphatic tissue increased to 137.8% and 134.7%, respectively, 4 and 7 h after the start of surgery. The results indicate that major surgery induces a redistribution of lymphocytes from peripheral blood to lymphatic tissue. It is suggested that the endocrine stress response may be of major importa

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1993.tb03708.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

The effects of a dose of beclomethasone inhaler (50 μg) or lidocaine 10% spray on postoperative sore throat were studied in 120 patients undergoing tracheal intubation for elective surgical procedures. Fifty‐four patients (90%) in the beclomethasone group scored no postoperative sore throat compared with 27 (45%) in the lidocaine group (P<0.00l). Beclomethasone inhaler seems to be highly effective in the prevention of postoperative sore throat and is therefore to be recommended before tracheal intubation for general anaesthes

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1993.tb03709.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

The effect of isoflurane administration on diaphragmatic activity was investigated in six anaesthetized mechanically ventilated dogs. Diaphragmatic strength was assessed by measuring the transdiaphragmatic pressure (Pdi) generated during supramaximal stimulation of both cervical phrenic nerves at frequencies of 0.5, 10, 20, 50 and 100 Hz under partially isometric conditions at 1, 1.5 and 2 minimum alveolar anaesthetic concentrations (MAC), after maintaining 1 h of stable conditions. Pdi measurements were made at the start of the stimulation (initial) and at the end of a 2‐s period (2‐s). The force‐frequency relationship was compared at each anaesthetic level. For single twitch (0.5 Hz) stimulation, the time constant of diaphragmatic relaxation was also assessed. The sequence of changing anaesthetic depth was altered in random fashion between animals. Pdi amplitude at single twitch stimulation was unchanged at the three anaesthetic concentrations. There was no significant difference in initial Pdi at various stimulus frequencies with increasing depth of isoflurane anaesthesia. In addition, no change in 2‐s Pdi during low frequency stimulation (10 and 20 Hz) was noted during any of the three levels of anaesthesia. By contrast, 2‐s Pdi with 50 Hz stimulation during 2 MAC isoflurane exposure decreased significantly below Pdi levels seen at 1 and 1.5 MAC (P

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1993.tb03710.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

The effects of 14 non‐steroidal anti‐inflammatory drugs (NSAIDs) ‐naproxen, ibuprofen, mefenamic acid, ketoprofen, indomethacin, fenoprofen, diclofenac sodium, aspirin, salicylic acid, piroxicam, sulindac, fenbufen, flurbiprofen and benzydamine, on the plasma protein binding of thiopental and the clinical consequences of such interactions were studied. Four of them, naproxen, ibuprofen, salicylic acid and aspirin, very significantly decreased the protein binding of thiopental in uitro in human plasma (P<0.005). Structurally, they were salicylates and propionic acid derivatives among the six classes of NSAIDs studied. The aspirin study demonstrated that the protein‐displacing phenomenon was temperature‐dependent, and concentration‐dependent. Clinically, aspirin administered intravenously resulted in a significant increase in the percentage of plasma free thiopental from 16.01 ± 3.59% to 22.27 ± 3.96% (P<0.001, n = 10) in patients undergoing surgery, and resulted in three of seven patients sleeping again during recovery from thiopental‐induced anesthesia. Although the effect of chronic use of NSAIDs before anesthesia is uncertain, studies should be carried out to find out if naproxen, ibuprofen, and aspirin influence the depth of anesthesia, time of recovery and duration of actio

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1993.tb03711.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

The incidence and intensity of muscle fasciculations as well as the occurrence of cardiac arrhythmias following succinylcholine were evaluated in 36 premedicated children (1.0–5.7 years) after intravenous induction with thiopentone or after inhalation induction with isoflurane (3.75 vol‐% in 70% nitrous oxide in oxygen). The study was randomized. In the thiopentone group, fasciculations were seen in all children and in the isotlurane group in 5 of 18 children (P<0.001). The median of the duration of fasciculations was 15 s with a minimum of 5 s and maximum of 36 s (1st quartile 9 s and 3rd quartile 20 s) in the thiopentone group and 0 (0–15) s with a 1st quartile of 0 and a 3rd quartile of 3 s in the isoflurane group (P<0.001). No cardiac arrhythmias were noted in either group. In conclusion, isoflurane in nitrous oxide inhibits succinylcholine‐induced muscle fasciculations in c

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1993.tb03712.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Ten patients undergoing open‐heart surgery received postoperative autotransfusion of shed mediastinal blood collected in the cardiotomy reservoir. The number, function and morphology of the platelets found in the shed blood were investigated. Platelets were counted using an electronic counter compared with light microscopy. Morphology of platelets was studied with electron microscopy. Platelet aggregation was studied using an aggregometer. Dense granule secretion was measured as the extracellular appearance of adenosine triphosphate. Enumeration of platelets in shed blood using the two methods gave different results. Thus, the electronic counter gave a mean platelet count of 62. 109.1‐1, while light microscopy revealed only a mean platelet count of 10. 109. 1‐1. Electron microscopy disclosed few platelets, but numerous cytoplasmatic fragments smaller than or up to the same size as platelets. The platelets found were mostly shape‐changed, spheroid, characterized by centralization and loss of alpha‐granules and dense bodies, all changes that indicated irreversible platelet activation. The platelets failed to aggregate in response to the presence of thrombin, adenosine diphosphate or collagen, and secretion of adenosine triphosphate was absent. Plasma from the shed blood was not capable of inducing spontaneous aggregation in platelet‐rich plasma from healthy donors. These results indicate that infusion of larger volumes of autotransfused blood should be supplemented with platelet c

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1993.tb03713.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

A study was conducted to examine the direct vascular effect of ropivacaine, in comparison with the effect of bupivacaine and lidocaine. Changes in tension induced by ropivacaine (10‐5‐3 × mol 1‐1), bupivacaine (10‐5‐3 times 10‐3mol 1‐1) and lidocaine (10‐5‐10‐2mol 1‐1) were examined cumulatively in vascular rings of dog femoral artery and vein under basal tension, or in those which had been precontracted with phenylephrine submaximally in Krebs' bicarbonate solution at 37°C aerated with 95% O2and 5% CO2(pH 7.4). The change in tension induced by lo‐2moll‐1ropivacaine was tested under basal tension in vascular rings bathed in HEPES buffer (pH 6.8). Ropivacaine induced greater constriction than bupivacaine at concentrations over 10‐5mol 1‐1in vascular rings under basal tension (P<0.01). The maximal contraction was induced by ropivacaine at mol 1‐1, averaging 51.5± 2.8% (n = 11) and 27.0± 3.7% (n= 12) of the maximal contraction induced by epinephrine in the artery and vein, respectively, and the contractions induced by ropivacaine at 10‐3mol 1‐1were 16.3± 2.0% (n=11)and 5.5± 1.1% (n=9), respectively. Phenylephrine (10‐6mol 1‐1)‐precontracted artery was contracted significantly by ropivacaine at 3 times 10‐4mol 1‐1and mol 1‐1, and by bupivacaine at 3 times 10‐3mol 1‐1, whereas the phenylephrine 10‐6mol 1‐1)‐precontracted vein was relaxed by these anesthetics. Lidocaine did not exert constricting effects. It is concluded that ropivacaine is a potent vasoconstrictor, although its constrictive effect is slight at 10‐2m

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1993.tb03714.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

A single shot of 20 ml of 1%, 0.75% or 0.5% ropivacaine was administered epidurdlly (at L2/3 level) to 30 volunteers, in a double‐blind manner. The blockade of the rectus abdominis muscle was measured quantitatively by registration of the average rectified electromyographic signal (AREMG) at the T7, T9 and T11 motor segmental levels and with a qualitative test for blockade of the rectus abdominis muscle (the so‐called RAM test). The maximal cranial spread ofanalgesia, evaluated by the pin‐prick method, was not significantly different for the three concentrations (T8‐T10 dermatome; median value). The intensity of motor blockade, measured by the AREMG method, increased progressively from the T7 segment and caudally with all three concentrations. The blockade was partial (Le. 85–25% of baseline AREMG activity was present at its maximum) in all subjects. When the effect of the three concentrations of ropivacaine was compared at the same segmental level, the intensity and duration of maximal motor blockade seemed to be dose‐dependent, but the difference was not statistically significant. The total duration of motor blockade was shorter with the 0.5% solution than with the higher concentrations. The AREMG method gave a more exact and graded picture of blockade of the rectus abdominis muscle than the RAM test. The duration of sensory blockade did not outlast motor blockade at any level. In half of our subjects the maximal spread of sensory blockade was either equal to or higher than the spread of partial motor block. In the other half, this relationship was reversed ‐ the maximal cranial level of partial motor block was 1–4 segments higher than the maximal lev

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1993.tb03715.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

With the aim of studying the pathophysiological background of the “TUR syndrome”, we gave six conscious ewes an intravenous infusion of 57 ml/kg of 1.5% glycine solution over 40 min. Isotonic saline infusions served as controls. Central haemodynamics were monitored. The plasma concentrations of protein, K, Na and vasopressin, and plasma osmolality were measured repeatedly for up to 4 h. The urinary excretions of Na, K and osmoles were also followed. Both infusions caused an elevation of the mean arterial pressure. With glycine, the pressure increased from 93 ± 4 to 112 ± 12 mmHg (12.4 ± 0.5 to 14.9 ± 1.6 kPa) (mean ± s.d.). The pulmonary capillary wedge pressure increased from 7±3 to 16±3 mmHg (0.9 ± 0.4 to 2.1 ± 0.4 kPa) and remained slightly elevated. The central venous pressure rose from 2 ± 3 to 11 ± 3 mmHg (0.3 ± 0.4 to 1.5 ± 0.4 kPa) but returned to baseline within 30 min after the infusion. Infusion of glycine resulted in a decrease in the plasma Na concentration from 144 ± 3 to 114 ± 4 mmol/l. The plasma osmolality decreased from 290 ± 2 to 280 ± I mosmol/l, and remained low. There was a median 6‐fold increase in plasma vasopressin concentration, while saline did not elicit vasopressin release. Despite the absence of electrolytes in glycine solution, the urinary excretion of sodium amounted to 106 ± 40 mmol. We conclude that i.v. infusion of 1.5% glycine solution in sheep causes a transient circulatory strain and natriuresis. Moreover, a vasopressin‐mediated reduction of maximal water excretion contributes to

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1993.tb03716.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY