Hemodynamic effects of fentanyl and sufentanil combined with flunitrazepam in coronary artery surgery

Because sufentanil has been reported as being able to prevent or treat peroperative hypertensive crises during aorto-coronary artery graft surgery, a study was carried out to compare the haemodynamic effects of sufentanil with those of fentanyl. 20 patients who were to undergo aortocoronary bypass grafting (CABG) were randomly allocated to two equal groups, sufentanil (Sf) and fentanyl (F) groups. A 1 to 5 dose ratio was used so as to have equipotent doses of sufentanil and fentanyl. Induction doses were 10 micrograms.kg-1 sufentanil and 50 micrograms.kg-1 fentanyl. Up to 20 micrograms.kg-1 sufentanil and 100 micrograms.kg-1 fentanyl were then used between intubation and the setting-up of cardiopulmonary bypass (CPB). A bolus of 10 micrograms.kg-1 flunitrazepam was given if necessary, so as to lower the mean arterial pressure (Pa) to below 100 mmHg after intubation, and under 80 mmHg during CPB. Heart rate, Pa, mean pulmonary arterial pressure, pulmonary wedge pressure (Ppw), central venous pressure and cardiac output were measured before anaesthesia, 2 min after intubation, before incision, 2 min after sternotomy, 10 min after the end of CPB, after chest closure, 30 min and 2h after arrival of the patient in the intensive care unit. The only difference found between the two groups was a more rapid drop in left ventricular preload after induction with sufentanil; 2 min after intubation, there was a 26% fall in Ppw with sufentanil (p less than 0.01) and 8% with fentanyl. Before skin incision, this drop was of 32% (p less than 0.01) and 24% (p less than 0.01) respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

Cardiovascular effects of, and catecholamine response to, high dose fentanyl or NLA in patients for valve replacement]

We measured the cardiovascular effect of, and catecholamine and other hormonal responses to, anesthetic doses of fentanyl and original NLA in 25 patients for open heart surgery. The patients were randomly divided into three groups (group N, F30, F75). During induction, in group N; droperidol 0.25 mg.kg-1 and fentanyl 5 micrograms.kg-1, in group F30; fentanyl 30 micrograms.kg-1, and in group F75; fentanyl 75 micrograms.kg-1 were administered intravenously. Additional fentanyl was administered at a rate of 100 to 200 micrograms.h-1. Droperidol 0.25 mg.kg-1 was administered in group N when cardiopulmonary bypass (CPB) was disconnected. Plasma samples were assayed for norepinephrine, epinephrine, ACTH and cortisol before and after induction, during sternotomy, 60 minutes after institution of CPB, after weaning from CPB, and before as well as after extubation. Heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP) and rate pressure product (RPP) were calculated simultaneously at the blood samplings. In all groups, no remarkable change in cardiovascular dynamics was observed. CPB was associated with marked increases in catecholamines, but high dose fentanyl in dose of 75 micrograms.kg-1 was able to suppress epinephrine level more than in group N. In high dose fentanyl group (F30, F75) ACTH was within normal ranges, even during CPB. The results suggest that high dose fentanyl is a complete anesthetic in patients for cardiac surgery. But a large dose of fentanyl causes small decreases in heart rate and arterial blood pressure. Our data indicate that group F30 is an attractive anesthetic technique for patients with valvular disease.     

Cardiopulmonary bypass-induced changes in plasma concentrations of propofol and in auditory evoked potentials

Unbound, rather than total, plasma concentrations may be related to the anaesthetic action of propofol. Therefore, we measured plasma concentrations of propofol and recorded Nb wave latencies of auditory evoked potentials (AEP) during continuous infusion of propofol in 15 patients undergoing coronary artery bypass grafting (CABG) surgery. After induction of anaesthesia with fentanyl, propofol was infused continuously at a rate of 10 mg kg-1 h-1 for 20 min, and then the rate was reduced to 3 mg kg-1 h-1. Administration of heparin before cardiopulmonary bypass (CPB) did not affect total or unbound propofol concentration. Initiation of CPB decreased mean total propofol concentration from 2.6 to 1.7 micrograms ml-1 (P < 0.01). Simultaneously, mean unbound propofol concentration remained at 0.06 micrograms ml-1 because of a slight increase in the mean free fraction of plasma propofol (from 2.3 to 3.5%; P > 0.05). During hypothermic CPB, mean total propofol concentration increased to concentrations measured before bypass (to 2.1 micrograms ml-1; P > 0.05 vs value before CPB) and the mean unbound propofol concentration was at its highest (0.07 microgram ml-1; P < 0.05 vs value before heparin). After CPB and administration of protamine, the mean total propofol concentration remained lowered (1.7 micrograms ml-1; P < 0.05 vs value before heparin) and the mean unbound propofol concentration returned to the level measured before heparin (P < 0.001 vs value during hypothermia). The latency of the Nb wave from recordings of AEP increased after induction of anaesthesia, reached its maximum during hypothermia and was prolonged during the subsequent phases of the study. The latency of the Nb wave did not correlate with total or unbound propofol concentration. We conclude that the changes in total and unbound concentrations of plasma propofol were not parallel in patients undergoing CABG. During CPB or at any other time during the CABG procedure, the unbound propofol concentration did not decrease and Nb wave latency was prolonged compared with baseline values measured after induction of anaesthesia before the start of CPB.      

Hormonal and metabolic responses to cardiac surgery with sufentanil-oxygen anaesthesia

The effects of sufentanil, 10 and 20 micrograms kg-1 on the hormonal and metabolic responses to coronary artery surgery were compared in 20 patients. The most important finding was that the changes in circulating beta-endorphin, ACTH, cortisol, GH, glucose, lactate and glycerol concentrations during and after cardiac surgery were similar with both doses of sufentanil. Although sufentanil prevented a significant increase in plasma beta-endorphin, ACTH and cortisol values until 6 h after cardiopulmonary bypass (CPB), a significant increase in GH secretion occurred with the onset of CPB. Plasma insulin concentrations declined significantly after 30 min CPB, but recovered after 60 min CPB with the restoration of normothermia. Blood glucose values did not change during surgery before CPB, but started to rise with the onset of CPB and continued to increase significantly in the postoperative period. Changes in blood lactate and plasma glycerol concentrations primarily reflected the load of CPB and the effects of heparin, respectively. The results show that increasing the dose of sufentanil up to 20 micrograms kg-1 does not result in better suppression of the endocrine and metabolic changes associated with cardiac surgery.     

CONTINUOUS INFUSION OF FENTANYL OR ALFENTANIL FOR CORONARY ARTERY SURGERY: Effects on Plasma Cortisol Concentration, {beta}-Endorphin Immunoreactivity and Arginine Vasopressin

Plasma cortisol, ß-endorphin immunoreactivity (PBE_ir)and arginine vasopressin (AVP) responses during and after thecontinuous infusion of fentanyl or alfentanil were studied in19 patients undergoing coronary artery bypass grafting (CABG).Plasma cortisol concentration decreased significantly in bothgroups during the anaesthesia and surgery before cardiopulmonarybypass (CPB); an increase was evident during CPB in both groups,but a statistically significant increase was not observed duringthe rest of the study, including the awakening from anaesthesia.PBE_ir increased with both opiates immediately after initiationof CPB and remained so during the rest of the study. There wereno significant changes in plasma AVP concentrations during anaesthesiaand surgery. After discontinuation of opiate infusions, an increasein AVP concentration commenced earlier in the alfentanil groupthan in the fentanyl group. At awakening from anaesthesia, asignificant correlation was observed between log plasma A VPconcentration and systemic vascular resistance. It is concludedthat, with continuous fentanyl and alfentanil infusions in atotal dose relationship of 1:13 in patients undergoing CABG,cortisol and AVP responses to surgery and CPB can be suppressed.However, during recovery from anaesthesia, the attenuating effectof alfentanil seems to wear off more rapidly than that of fentanyl.PBE_irresponse to CPB and emergence from anaesthesia could notbe prevented with either analgesic.     

Clinical study on total intravenous anesthesia with droperidol, fentanyl and ketamine--7. Effects on natural killer cell activity

Twenty four patients who underwent ophthalmic surgery were studied to evaluate activities of natural killer (NK) cells during and following total intravenous anesthesia with droperidol, fentanyl and ketamine. They were divided into three equal groups according to anesthetic methods employed. In enflurane group, anesthesia was induced with thiopental 5 mg.kg-1 and succinylcholine 1 mg.kg-1, and maintained with 1-2% enflurane, nitrous oxide (50%) and oxygen (50%). In original NLA group, anesthesia was induced as above and maintained with droperidol 0.15 mg.kg-1, fentanyl 5-10 micrograms.kg-1, nitrous oxide (70%) and oxygen (30%). The patients of total intravenous anesthesia group received droperidol 0.15 mg.kg-1, ketamine 2 mg.kg-1 and succinyl-choline 1 mg.kg-1 for induction of anesthesia, and then were given fentanyl 5-15 micrograms.kg-1, ketamine 2 mg.kg-1.hr-1 and oxygen (30%) for the maintenance of anesthesia. Vecuronium was given to every patient of the three groups for intraoperative muscle relaxation. Hartmann's solution was used at a speed of 5 ml.kg-1.hr-1. Peripheral venous blood 10 ml was drawn on six occasions during and after the surgery for the measurement of NK cell activities and endocrine response as judged by plasma catecholamine and cortisol levels. NK cell activities decreased significantly on the first post-operative day in enflurane group, but no significant differences were found among three groups in NK cell activities. The data suggest that inhaled anesthetics should not be easily employed for patients with depressed immune response, malignant disease and prolonged surgery.     

Alpha-atrial natriuretic peptide, antidiuretic hormone and aldosterone levels in patients undergoing aortocoronary grafting under high dose fentanyl anesthesia

Plasma concentrations of alpha-atrial natriuretic peptide (alpha-ANP), antidiuretic hormone (ADH) and aldosterone (ALDS) were determined by radioimmunoassay in 9 patients undergoing aortocoronary bypass grafting under high dose fentanyl (94.4 micrograms.kg-1) anesthesia. These three levels in pre-anesthetic period (control values) were within normal ranges suggesting the absence of congestion and dehydration. Although these values changed significantly after sternotomy, they all increased at the termination of cardiopulmonary bypass (CPB) reaching 2.5 fold in alpha-ANP, 27.7 fold in ADH and 2.4 fold in ALDS as compared with control (P less than 0.05). Present results indicate that high dose fentanyl anesthesia cannot suppress ADH and ALDS level during CPB as was previously demonstrated and the observed rise in alpha-ANP level is considered to be inadequate not only for diuresis but also for vascular dilatation. Administration of alpha-ANP to ameliorate circulatory insufficiency after CPB should probably be considered.     

体外循环旁路洗入七氟醚对冠状动脉旁路移植术患者心肌损伤的影响

目的 评价体外循环(CPB)旁路洗入七氟醚对冠状动脉旁路移植术(CABG)患者心肌损伤的影响.方法 择期CPB下行CABG的患者40例,年龄50 ～ 64岁,体重53～90 kg,ASA分级Ⅱ或Ⅲ级,采用随机数字表法,将患者随机分为2组(n=20):对照组(C组)和七氟醚组(S组).S组于CPB开始即刻通过体外循环机洗入1.0％ ～2.0％七氟醚,持续到CPB结束,C组不给予七氟醚.于麻醉诱导后5 min(T0)、术后6 h(T1)、12 h(T2)及24 h(T3)时采集血样,测定血浆心肌肌钙蛋白I(cTnI)浓度和磷酸肌酸激酶同工酶(CK-MB)活性.于主动脉阻断前和CPB结束时取右心耳组织,电镜下观察心肌超微结构,并行心肌细胞线粒体损伤评分.结果 与C组比较,S组T2和T3时血浆cTnI浓度,CPB结束时心肌细胞线粒体损伤评分降低(P＜0.05),血浆CK-MB活性差异无统计学意义(P＞0.05).S组心肌病理学损伤较C组减轻.结论 CPB旁路洗入七氟醚可减轻CABG术患者的心肌损伤.     

alpha 1-Adrenergic responsiveness during coronary artery bypass surgery: effect of preoperative ejection fraction

Elevated catecholamines and beta-adrenergic receptor hyporesponsiveness (or desensitization) have been demonstrated in failing human myocardium, but the role of the alpha-adrenergic receptor remains unclear. The authors tested the hypothesis that alpha 1-adrenergic responsiveness decreases in patients with impaired ventricular function undergoing coronary artery revascularization. Impaired ventricular function was defined prospectively by left ventricular ejection fraction less than or equal to 40% (group I, n = 12), and normal ventricular function by ejection fraction greater than 40% (group II, n = 22). Phenylephrine (Phe) pressor dose-response curves were established prior to anesthesia, during fentanyl anesthesia, and during fentanyl anesthesia plus hypothermic cardiopulmonary bypass at the time of aortic cross-clamp (anes + CPB/AXC). Polynomial regression of the Phe dose response curve estimated the Phe dose required to increase mean arterial blood pressure 20%, designated PD20. Although pre-anesthesia PD20 and anes + CPB/AXC PD20 values were not affected by ejection fraction, significant differences in PD20 (P less than 0.05) between groups occurred during fentanyl anesthesia (group I = 2.28 +/- 1.60 micrograms.kg-1, group II 1.57 +/- 0.98 micrograms.kg-1; mean +/- SD). Anes + CPB/AXC was associated with a significant reduction in PD20 in both groups compared with pre-anesthesia (P less than 0.01). Our results suggest impairment of alpha 1-adrenergic responsiveness occurs during fentanyl anesthesia in patients with ejection fractions less than or equal to 40% (evidenced by greater PD20 values). Although this impairment may be due to altered Phe pharmacokinetics, these results also support the possible existance of alpha 1-adrenergic receptor desensitization in this group. Reduction in PD20 during anes + CPB/AXC in all patients points to more powerful effects than fentanyl anesthesia alone; such influencing effects may include hemodilution, hypothermia, elevated plasma catecholamines, exclusion of the pulmonary circulation, or altered Phe pharmacokinetics.     

Changes in plasma endothelin in patients undergoing cardiac valve replacement under high dose fentanyl anesthesia

We measured plasma endothelin (ET) in 11 patients undergoing cardiac valve replacement under high dose fentanyl (116.6 +/- 15.4 micrograms.kg-1, mean +/- SD) anesthesia. Arterial blood samples were obtained: 1) before induction of anesthesia (control), 2) just before the start of cardiopulmonary bypass (CPB), and 3) just before the end of CPB. Endothelin levels were analyzed by radioimmunoassay based on double antibody method using Silica ODS suspension. ET concentrations in period 1, 2, and 3 were 3.0 +/- 1.1, 4.2 +/- 1.7 and 4.5 +/- 1.8 pg.ml-1 (mean +/- SD), respectively. There were no significant differences among these three values (P less than 0.05). The results suggest that under high dose fentanyl anesthesia, surgical stress including that of CPB might not affect ET concentration in plasma.     

Changes in endothelin in plasma in patients undergoing coronary artery bypass grafting under high dose fentanyl anesthesia]

We measured plasma endothelin-1 (ET) in 10 patients undergoing coronary artery bypass grafting under high dose fentanyl (107.0 +/- 11.9 micrograms.kg-1, mean +/- SD) anesthesia. Arterial blood samples were obtained: 1) before induction of anesthesia (control), 2) just before the start of cardiopulmonary bypass (CPB), and 3) just before the end of CPB. ET levels were analyzed by radioimmunoassay based on double antibody method using Silica ODS suspension. ET concentrations in period 1, 2, and 3 were 1.8 +/- 0.7, 3.4 +/- 1.1 and 3.1 +/- 1.3 pg.ml-1 (mean +/- SD), respectively. There were significant differences between the control value and the values obtained at periods 2 and 3 (P less than 0.05). The elevation in ET level before CPB suggests the existence of hidden coronary ischemia despite the absence of detectable sign indicating myocardial oxygen supply demand imbalance. It was also suggested that, under high dose fentanyl anesthesia, stress evoked by CPB might not affect plasma ET concentration.     

Effects of olprinone hydrochloride after coronary artery bypass grafting

BACKGROUND: We have examined the effect of olprinone hydrochloride on hemodynamics and peripheral circulation after cardiopulmonary bypass (CPB) in 56 patients who underwent coronary artery bypass grfting. METHODS: The subjects were randomly classified into 2 groups: B-group of 25 patients who received bolus plus continuous administration of olprinone hydrochloride and control group without administration of olprinone hydrochloride (C-group) of 31 patients. In the B-group, after de-clamping of the aortic occlusion, olprinone hydrochloride 15 micrograms.kg-1 bolus was administered and followed by continuous administration at 0.1 microgram.kg-1.min-1. RESULTS: We excluded six cases in C-group in whom it was not possible to maintain blood pressure without olprinone hydrochloride. In the B-group, peripheral temperature was kept significantly higher and blood lactic acid value was kept significantly lower until 6 hours after the operation compared with C-group. In the B-group, cardiac index was kept significantly higher for a long period of time, and dosage of concomitantly used catecholamine could be significantly reduced. CONCLUSIONS: Olprinone increased CI and decreased SVRI, and it led to easy weaning from CPB, providing excellent hemodynamics after CABG. These results suggest that olprinone hydrochloride 15 micrograms.kg-1 bolus plus 0.1 microgram.kg-1.min-1 continuous administration may be effective for improvement of hemodynamics and peripheral circulation after CPB.     

Dose requirements of infusions of cisatracurium or rocuronium during hypothermic cardiopulmonary bypass

We investigated the influence of mild hypothermic cardiopulmonary bypass (CPB) on the dose requirements of cisatracurium or rocuronium used as a continuous infusion. We studied eight patients given cisatracurium and nine given rocuronium. They were ASA class III and IV and scheduled for elective coronary artery bypass grafting. Neuromuscular transmission was monitored electromyographically. After recovery of T1/T0 to 10%, a cisatracurium infusion or a rocuronium infusion was started at a rate of 1.5 or 10 micrograms kg-1 min-1, respectively, and adjusted to maintain T1/T0 at 15%. Infusion rate and duration were recorded before, during and after CPB in each patient and the mean infusion rates were calculated. One-way ANOVA showed a statistically significant difference between the cisatracurium infusion rates before, during and after CPB: A T1/T0 of 15% could be achieved with a mean infusion rate of 1.1, 0.75 and 0.98 micrograms kg-1 min-1 before, during and after CPB, respectively. There was no significant difference between the rocuronium infusion rates before, during and after CPB. The mean rocuronium infusion rate required to maintain T1/T0 at 15% throughout the procedure was 4.1 micrograms kg-1 min-1. Cisatracurium infusion rates should be halved during CPB. Even after CPB, requirements are reduced. The same tendency occurs with rocuronium, but the changes in infusion rate were not statistically significant.     

Haemodynamic and plasma vasopressin responses during high-dose fentanyl or sufentanil anaesthesia

This study compared the haemodynamic and arginine vasopressin responses of patients to fentanyl or sufentanil anaesthesia for coronary artery bypass surgery. Fourteen normotensive patients with normal left ventricular function were studied. Patients were induced with fentanyl (N = 7) 37.5 micrograms X kg-1 or sufentanil (N = 7) 7.5 micrograms X kg-1 by intravenous infusion over three minutes. Clinically important chest wall rigidity, bradycardia and recall of intraoperative events did not occur. All of the fentanyl patients became hypertensive after induction and five required vasodilator therapy since they did not respond to boluses of fentanyl (12.5 micrograms X kg-1). Two of these five patients had S-T depression greater than 1 mm. Five patients in the sufentanil group became hypertensive after induction. Four of these patients responded to additional sufentanil (3.75 micrograms X kg-1) while one required vasodilator therapy for concomitant S-T depression. Sufentanil attenuated the increase of arginine vasopressin during cardiopulmonary bypass. Levels of arginine vasopressin in the fentanyl group were significantly higher than those of the sufentanil group during bypass. Levels of AVP after bypass were higher in the sufentanil group. The incidence of hypertension was similar in both groups. The hypertension was more easily treated with sufentanil but concomitant vasodilators (nitroglycerine) were required in both patient groups. Neither fentanyl in doses up to 128 +/- 8.7 micrograms X kg-1 nor sufentanil in doses up to 23 +/- 1.4 micrograms X kg-1 can be used as sole agents for anaesthesia in adult coronary artery bypass patients with good ventricular function when induction times are three minutes and bolus top-up doses are used.     

冠状动脉搭桥术患者围手术期皮质醇昼夜人泌节律与神经心理状态的研究

目的研究冠状动脉搭桥术患者围手术期皮质醇昼夜节律变化与神经心理状态的关系.方法选择在低温体外循环或非体外循环下行冠状动脉搭桥术的男性患者40例,分为体外循环组和非体外循环组,每组20例.在术中特定时点和术后每3 h抽血1次持续到术后24 h.用放射免疫法检测血浆皮质醇的含量.于术前1 d、术后7～10 d及术后3个月,应用抑郁自评量表、焦虑状态/特性询问表和神经心理量表评估抑郁和焦虑程度以及认知功能.结果术后24 h体外循环组和非体外循环组分别有3例和7例患者表现为昼夜节律性分泌,其余患者则无昼夜节律性分泌.体外循环组和非体外循环组患者术后抑郁评分高于术前(P<0.01),而体外循环组患者术后7～10 d焦虑状态显著重于非体外循环组患者(P<0.05);体外循环组患者的数字广度测验(逆向)评分低于非体外循环组患者(P<0.05);斯特鲁字色干扰测验的改正反应和阻塞反应较非体外循环组患者显著减退(P<0.05).体外循环组患者术后皮质醇昼夜分泌节律紊乱与抑郁程度和斯特鲁字色干扰测验的改正反应相关, 而非体外循环组患者皮质醇分泌节律紊乱则与抑郁程度、数字广度测验(顺向)、符号数字模式测验和斯特鲁字色干扰测验的改正反应相关.抑郁程度与认知功能的某些项目相关.结论冠状动脉搭桥术患者围手术期皮质醇昼夜分泌节律紊乱,这种紊乱直接或通过情感状态间接与认知功能相关.     

冠状动脉搭桥术后中枢神经系统并发症病人围术期神经内分泌和术后神经心理的变化

目的观察冠状动脉搭桥术后中枢神经系统并发症病人围术期血浆褪黑激素、皮质醇和神经元特异性烯醇化酶（NSE）和术后神经心理的变化。方法择期在体外循环下行冠脉搭桥术病人3例，在术后分别出现脑梗塞、运动性失语、运动性和感觉性失语的中枢神经系统并发症。3例病人均在麻醉诱导前、气管插管后10min、肝素化后10min、转机后30min、中和肝素前、关胸缝皮后、回到ICU即刻、术后3、6、9、12、15、18、21、24h抽血，分别用酶联免疫和放射免疫法测定血浆褪黑激素、皮质醇和NSE的浓度。在术前1d、术后10-20d及术后3个月，应用抑郁自评量表、焦虑状态，特性询问表和神经心理量表评估抑郁和焦虑程度以及认知功能。结果三例病人术后NSE浓度在不同时点升高。术后24h内病例1和病例2褪黑激素和皮质醇昼夜分泌节律紊乱；病例3的褪黑激素和皮质醇则表现昼夜分泌节律。病例1和病例3术后连线测验A型、符号数字模式测验和斯特鲁字色干扰测验减退；术后抑郁程度增高，但焦虑程度减轻。结论冠状动脉搭桥术后神经系统并发症病人认知功能减退，情绪紊乱；这些改变可能与病人围术期NSE浓度升高，褪黑激素和皮质醇昼夜分泌节律紊乱有关。     

The effects of milrinone on hemodynamics in patients undergoing cardiac surgery

The phosphodiesterase inhibitor, milrinone is used to treat low cardiac output syndrome, especially after cardiac surgery. But there were few reports about the precise hemodynamic effects at separation from cardiopulmonary bypass (CPB). We examined the hemodynamic effects of milrinone in 24 patients undergoing elective coronary artery bypass graft (CABG). Patients were assigned to the milrinone group (n = 12) and the control group (n = 12). Before separation from CPB, milrinone was administered as a loading dose of 50 micrograms.kg-1 into the reservoir of CPB at rectal temperature 33.5 degrees C and simultaneously a continuous infusion of 0.5 microgram.kg-1.min-1 was started. In addition, dopamine and nitroglycerine were administered in both groups. Hemodynamic measurements were performed before CPB, just after the weaning from CPB, 15, 30, 60 minutes after the weaning from CPB. Cardiac index increased significantly (P < 0.01) in the milrinone group as compared with the control group. Systemic vascular resistance index and mean arterial pressure decreased significantly (P < 0.0001, P < 0.05, respectively) in the milrinone group as compared with the control group. There were no significant differences in heart rate, mean pulmonary arterial pressure, pulmonary artery occlusion pressure, mean right atrial pressure, stroke volume index, and pulmonary vascular resistance index between the two groups. These hemodynamic effects showed that milrinone supported cardiac performance after CPB for CABG.     

Isoflurane decreases the cortisol response to cardiopulmonary bypass

Eighteen patients with normal left ventricular function scheduled for elective myocardial revascularization were anesthetized with fentanyl (52-58 micrograms/kg). At the beginning of hypothermic cardiopulmonary bypass (CPB) they were assigned to a control (C) group (n = 6) that did not receive further anesthesia, or to a group given either 1% isoflurane (n = 6) or 2% isoflurane (n = 6). Blood samples for measurement of total plasma cortisol concentrations were obtained before, during, and after CPB. Hemodynamic measurements before and after CPB were not different among groups. Patients in group C required higher infusion rates of sodium nitroprusside (P less than or equal to 0.05) and patients given 2% isoflurane received more phenylephrine (P less than or equal to 0.05) to keep mean arterial pressure at 50 +/- 10 mm Hg during CPB. Isoflurane caused a dose-related decrease in total plasma cortisol concentrations during and after CPB. We conclude that increased depth of anesthesia attenuates the cortisol (stress) response to cardiopulmonary bypass.     

Comparison of sufentanil and fentanyl anesthesia for coronary artery bypass grafting--changes in stress hormones

We compared the changes in hemodynamics and stress hormones in 30 patients who received for CABG operation either sufentanil-oxygen or fentanyl-oxygen anesthesia. The mean doses of fentanyl and sufentanil for intubation were 1.66 +/- 0.69 mg and 0.35 +/- 0.14 mg respectively and mean total doses were 6.91 +/- 1.14 mg and 1.68 +/- 0.38 mg, or 21.4 micrograms.kg-1.hr-1 and 4.5 micrograms.kg-1.hr-1 respectively. SAP decreased significantly immediately before intubation in both groups. Immediately after intubation, a significant intergroup difference (P less than 0.05) was noted. The changes in DAP and MAP were almost similar to those of SAP. This study demonstrates that sufentanil-oxygen anesthesia gave more stable hemodynamic parameters before and after intubation. Especially no significant changes in heart rate occurred immediately after intubation and with CABG operation, thus preventing the increase in rate pressure product during procedure. Sufentanil anesthesia did attenuate more effectively the stress hormones release than high dose fentanyl anesthesia, but neither sufentanil nor fentanyl anesthesia could prevent the increases in these hormones postoperatively.     

A comparison of hemodynamic changes with sufentanil-O2 and fentanyl-O2 anesthesia for coronary bypass grafting

Hemodynamic changes were investigated in twenty patients undergoing coronary artery bypass grafting. Thirteen patients received sufentanil-O2 anesthesia and seven patients had fentanyl-O2 anesthesia. Systolic, diastolic, as well as mean arterial blood pressures, heart rate and rate pressure product (RPP) were measured before and after intubation, one minute after skin incision, and one minute after sternotomy. The sufentanil group received 3-5 micrograms.kg-1 of sufentanil for induction and a continuous infusion of 2.5-5.0 micrograms.kg-1.hour-1. The fentanyl group received 10 to 20 micrograms.kg-1 for induction and a continuous infusion of 12.5 micrograms.kg-1.hour-1. In sufentanil group, a decrease of systolic as well as mean arterial pressure, heart rate and RPP was observed following induction. These results showed effective blocking of the sympathetic reflex by sufentanil. In the fentanyl group, immediately after intubation, an increase in systolic pressure, mean pressure, heart rate and RPP was observed. Particularly RPP increased to more than 12000 at this moment. Diastolic pressure was not significantly changed in each group. Stable hemodynamic parameters with no ST-T change were noticed during surgical procedure in each group. We conclude that sufentanil is a superior narcotic agent than fentanyl for the patients undergoing CABG, and it effectively blocks sympathetic reflex activity.