ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1991.tb03330.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Porcine and human renal physiology are similar in important aspects. Renal cortical microcirculation and its relation to inulin clearance (CIn) was therefore studied before and after renal ischaemia in 28 pigs under continuous intravenous chlormethiazole‐pancuronium anaesthesia. The anaesthesia used provided essential stability in central haemodynamics. The animals were studied for 90 min of reperfusion following 0, 30 or 60 min of renal ischaemia. Twelve of the animals (four were subjected to each duration of ischemia) were also studied 18 h after start of reperfusion. Regional blood flow in the superficial renal cortex was measured by laser Doppler flowmetry (LDF), and tissue oxygenation (Pto2) by surface microelectrode technique. These techniques allow continuous or repeated measurements. During the first 90 min of reperfusion, superficial renal cortical blood flow measured by LDF (Qsrc) underwent considerable temporal variation which followed a certain pattern. Thus, when the renal arterial blood flow was restored after ischaemia, we observed an instant peak in Qsrcfollowed by a decreasing flow until a minimum value (Qmin) was reached between 3 and 9 min after start of reperfusion (tQmin). Thereafter, Qsrcincreased until a maximal value (Qmax) was reached between 11 and 64 min after start of reperfusion (tQmin). The parameters tQminand tQmaxwere related to inulin clearance 18 h after start of reperfusion (P<0.05 andP<0.01, respectively). Thus, it might be possible soon after start of reperfusion – to evaluate the severity of ischaemic damage. This could be useful in the evaluation of different prophylactic strategies, since the full extent of the ischaemic damage, as assessed by clearance determinations, cannot be established until hours later. In both groups the renal cortical tissue oxygenation 15 min after start of reperfusion was fairly similar to that before ischaemia. However, re‐oxygenation of the superficial renal cortex was more rapid after 30 min of ischaemia compared with that after 60 min. Regional lack of oxygen due to increased microcirculatory heterogeneity despite adequate regional blood flow measured by LDF was also ruled out. The impairment in inulin clearance during the first 90 min postischaemia was not related to reduced oxygen availability in the superficial renal c

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1991.tb03331.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Regional microcirculatory differences in the superficial renal cortex were studied before and during 4 h following 60 min of renal ischaemia in seven pigs under continuous intravenous chlormethiazole‐pancuronium anaesthesia. Superficial renal cortical blood flow (Qsrc) was measured by laser Doppler flowmetry (LDF) in two different regions. In two other different regions tissue oxygenation (Pto2) was measured by surface electrodes. Thus, microcirculatory measurements were simultaneously carried out in each animal in four different regions of the left kidney. After 60 min of renal ischaemia, pronounced renal cortical microcirculatory disturbances were found. The regional microcirculatory differences were notable, especially after ischaemia. On average, Qsrcwas 49 ± 11 (s.d.) arbitrary units at baseline and decreased to 24 ± 4 arb. units 4 h after start of reperfusion (P<0.05). Before ischaemia the average difference between Qsrcsimultaneously measured in two different parts of the renal cortex was 26 ± 15% of the mean of both measurements, and it was 30 ± 22% 4 h after start of reperfusion (n.s.). Mean Pto2(m‐Pto2) was on average 4.5 ± 1.3 kPa at baseline and 2.4 ± 1.5 kPa 4 h after start of reperfusion (P<0.05). The average difference between m‐Pto2simultaneously measured in two different parts of the renal cortex at baseline was 24 ± 13% of the mean of both measurements and 57 ± 49% 4 h after start of reperfusion (n.s.). In each of the two measured regions of the renal cortex m‐Pto2was calculated from 160 small tissue volumes distributed within a surface area of about 1 mm2. The percentage of these 160 measurements which exhibited Pto2<0.6 kPa (L‐Pto2) was, on average, 1 ± 2% at baseline and increased to 19 ± 25% 4 h after start of reperfusion (P<0.05). The average difference in L‐Pto2between the two measured regions was 1 ± 3% at baseline and 17 ± 21% 4 h after start of reperfusion (n.s.). The microcirculatory disturbances after ischaemia were strongly dependent on the elapsed time after start of reperfusion. Thus, measurements by techniques allowing continuous or repeated recordings are advantageous. Due to regional variability, Pto2and LDF measurements from several animals or from multiple regions in the renal cortex must be considered in order adequately to describe the postischaemic renal co

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1991.tb03332.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Differentin vitrohalothane testing procedures have been used in the European malignant hyperthermia (MH) Group Protocol (EMHGP) and the North American MH Group Protocol (NAMHGP), whereas the caffeine‐testing protocols are very similar. The present study compares the two halothane‐testing protocols in ten MH susceptible swine and in four control swine. Halothane contracture testing was conductedin vitro12–52 days following the barnyard challenge that established the MH susceptibility of the swine. There was one false positive and one false negative halothane test by the EMHGP. The MH‐equivocal category in the EMHGP, which is treated clinically as MH‐susceptible, affords a margin of safety in such cases. In contrast, there were no false halothane tests by the NAMHGP. While some skeletal muscle strips from MH pigs were normal by both protocols (NAMHGP 30%; EMHGP 10%), the outcome of halothane testing by the NAMHGP was unaffected. The response to halothane 3% is reduced if preceded by the EMHGP, suggesting that simply adding halothane 3% to the end of the EMHGP does not permit a direct quantitative comparison to the NAMHGP. However, the diagnostic outcomes of the two approaches ar

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1991.tb03333.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Bupivacaine is a local anesthetic commonly used in obstetrical practice. Although not generally constrictive, it has a constricting effect on blood vessels in clinically used doses, and when administered close to the uterine vasculature, as in a paracervical blockade, it can induce severe fetal bradycardia and thus be hazardous to the fetus. The bupivacaine‐induced vasoconstriction on uterine arteries from pregnant and non‐pregnant women was effectively reduced by two different calcium antagonists, verapamil and nifedipine. In non‐pregnant women, nifedipine (2.9 times 10‐2mol·l‐1) administered simultaneously with bupivacaine (5.8 times 10‐1mol·l‐1) caused a 96% and verapamil (10‐5mol·l‐1) an 84% reduction as compared with the control vessel where only bupivacaine (5.8 times 10‐4mol·l‐1) was administered. In pregnant women, nifedipine 2.9 times 10‐1mol·I‐1and 2.9 times 10‐6mol·l‐1produced 66% and 79% reductions, respectively. It is possible that calcium antagonists administered together with bupivacaine in paracervical blockade could r

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1991.tb03334.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

To evaluate the individual predictability of spinal anaesthesia, 10 patients (3 women and 7 men) scheduled for control cystoscopy were studied twice within 9 months. Lumbar puncture was performed in the midline at the L2/3 interspace with the patient in the sitting position using plain 0.5% bupivacaine at 37d̀C. A non‐parametric Spearman test showed that, on the basis of the first block, the predictability of the cephalad analgesic spread of the second anaesthesia was high up to 60 min after injection. Thereafter the predictability decreased. The predictability of the motor blockade was generally low. Six patients obtained complete motor blockade twice; the remaining four, on

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1991.tb03335.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Deliberate hypotension may induce secretion of stress hormones. In the present study, the effects of hypotension induced by labetalol with isoflurane on plasma renin activity, plasma concentrations of adrenaline, noradrenaline, vasopressin, and aldosterone were investigated in eight adult patients undergoing middle‐ear surgery. The mean arterial pressure was 50 mmHg (6.7 kPa) during hypotension. Plasma renin activity rose significantly during anaesthesia before hypotension, being similar during hypotension and before hypotension, and it returned postoperatively to the initial level. Plasma adrenaline fell significantly during hypotension and rose after anaesthesia to the preanaesthetic level. Plasma noradrenaline rose slightly during hypotension and after anaesthesia, but not significantly. Plasma vasopressin rose significantly after anaesthesia. Plasma aldosterone increased slightly throughout the study, but not significantly during any phase. In conclusion, labetalol with isoflurane‐induced hypotension seems to attenuate the stress response in these operations. During hypotension, plasma renin activity is not an essential compensatory mechanism, which antagonises the decrease of blood pressure. Plasma vasopressin has no role in regulating blood pressure during labetalol‐induced hypote

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1991.tb03336.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

The object of this study was to investigate whether pretreatment with pancuronium before i.v. injection of suxamethonium could cause prolonged neuromuscular blockade in patients heterozygous for the usual and the atypical plasma cholinesterase gene (E*1E*1). Forty‐three patients, 23 with genotype E*1E*1* and 20 with normal genotype (E*1E*1), were pretreated with pancuronium 0.01 mg‐kg‐1followed by suxamethonium 1.5 mg‐kg‐1, and received either neurolept anaesthesia or halothane anaesthesia. Seven patients (E*1E*1) were given suxamethonium 1.5 mg‐kg‐1without pretreatment. The duration and type of neuromuscular block were evaluated using train‐of‐four (TOF) nerve stimulation. Type of anaesthesia did not significantly influence the results. The duration of block following pretreatment was significantly longer in heterozygous patients than in normal patients. Time to 90% twitch height recovery was 10.7 ± 1.2 min (mean ± s.d.) in genotypically normal patients, and 18.0 ± 4.2 min in patients with genotype E*1E*1. Pretreatment with pancuronium caused a significantly slower recovery of the TOF ratio (phase II block). Thus, a TOF ratio of 0.7 was always reached within 13 min in genotypically normal patients. In genotypically abnormal patients, the same TOF ratio was reached within 20 min in all but three patients. In these three patients time to 90% twitch height recovery was prolonged (18–31 min), and TOF ratio did not return to normal, but stabilized at about 0.35, 0.50, and 0.65, respectively. Injection of edrophonium restored normal neuromuscular function in 10 min. It is concluded that in patients heterozygous for the usual and the atypical gene, pretreatment with pancuronium in combination with an increased dose of suxamethonium may cause a phase II block and thus a prolong

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1991.tb03337.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

The effect of thoracic epidural anesthesia (TEA) on the ischemic myocardium was examined in open‐chest dogs anesthetized intravenously. Ischemia induced by brief coronary artery occlusion caused an elevation of the ST segment in epicardial ECG and a reduction in myocardial pH and contractile force. TEA with 0.15 ml/kg of 0.4% bupivacaine solution attenuated an ischemia‐induced decrease in myocardial pH and an increase of the ST segment in epicardial ECG. This attenuation was maintained even after the restoration of blood pressure and heart rate, which had been decreased significantly after TEA, to pre‐TEA levels, suggesting that a beneficial effect of TEA should not be confined to its hemodynamic changes such as decreased blood pressure and heart rate. In contrast, the subendocardial contents of ATP, creatine phosphate (CP) and lactate were not affected by TEA, either in the presence or the absence of 5 min LAD occlusion. These results suggest that neither hemodynamic nor metabolic changes are responsible for the reduced myocardial ischemic acidosis induced by TEA after brief coronary artery occlusion. The acidosis‐saving property of TEA is favorable for the ischemi

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1991.tb03338.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

The analgesic efficacy and side‐effects of combined epidural infusion of bupivacaine and morphine, in comparison with these drugs alone, for postoperative analgesia after hysterectomy (60 patients) were evaluated. Before general anaesthesia, all patients had an epidural catheter placed (Th11‐12) and 20 ml of 0.5% bupivacaine was injected. In random order, epidural infusion was continued for 24 h with either 0.25% bupivacaine 4 ml‐ h‐1(BUPI‐group), a bolus of 2 mg of morphine followed by morphine 0.2 mg‐ h‐1(MO‐group), or a combination of the two drugs (COMB‐group). A urinary bladder catheter was kept for 24 h. Supplementary postoperative pain medications were i.m. morphine 0.1 mg‐ kg‐1or rectal indomethacin 50 mg, on request. Immediately after awakening from general anaesthesia and transfer to the recovery room, 18/20 of the BUPI‐group patients, 17/20 of the MO‐group patients and 19/20 of the COMB‐group patients were pain‐free. In the postoperative evening and the first postoperative morning, the corresponding figures were 7/20 and 10/20 in the BUPI‐group, 15/20 and 15/20 in the MO‐group, and 18/20 and 15/20 in the COMB‐group (postop. evening;P<0.01 BUPI vs. others). The number of patients requiring supplementary analgesics (morphine and indomethacin) during the first 24 h was greatest in the BUPI‐group (P<0.01). The number of patients who vomited during the 24‐h period was 3 in the BUPI‐group, 9 in the MO‐group and 5 in the COMB‐group. Postoperatively, normal bowel function was restored after 1.9 days in the BUPI‐group, 2.2 days in the MO‐group and 2.6 days in the COMB‐group, on average (P<0.01 BUPI vs. COMB). Recatheterization of the urinary bladder (once) was required in 4 patients in the MO‐group and 2 in the COMB‐group, but in none of the BUPI‐group. It is concluded that although the morphine‐containing epidural infusions (6.8 mg 24 h‐1) were superior to that containing bupivacaine alone with respect to postoperative analgesia after hysterectomy, the occurrence of disturbing emetic and u

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1991.tb03339.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY