Comparison of the hemodynamic effects of sevoflurane anesthesia induction and maintenancevs TIVA in CABG surgery

PURPOSE: To compare the hemodynamic effects of sevoflurane when used for induction and maintenance of anesthesia with a total intravenous technique in patients with known coronary artery disease (CAD). METHODS: Thirty patients undergoing elective coronary artery bypass graft (CABG) were randomly allocated to receive either sevoflurane (S group, n = 15) at a minimal concentration of 4% in oxygen for induction and at 0.5-2 MAC end-tidal concentration for maintenance, or a total intravenous technique (T group, n = 15) consisting of midazolam for induction and propofol for maintenance. In both groups, anesthesia was supplemented with sufentanil and muscle relaxation with cis-atracurium. Hemodynamic measurements included systemic and pulmonary pressures, heart rate, mixed venous oxygen saturation and cardiac output at the following times: pre-induction, 7 and 25 min post-induction, chest closure, one hour after surgery and pre and post tracheal extubation. RESULTS: More patients in the S group (8/15) presented bradycardia in the induction period (T:2/15) (P = 0.05). During maintenance of anesthesia, treatment of hypertension was more frequent in the T group (12/15) than in the S group (6/15) (P = 0.025). All other parameters were comparable. CONCLUSION: Induction of anesthesia in patients with CAD, VCRII with sevoflurane supplemented by sufentanil provided hemodynamic responses comparable with those of TIVA although bradycardia was observed more often with sevoflurane. Intraoperative control of systemic blood pressure was achieved with fewer interventions with a sevoflurane/sufentanil maintenance than with a propofol/sufentanil technique in CABG surgery.     

Sevoflurane provides greater protection of the myocardium than propofol in patients undergoing off-pump coronary artery bypass surgery

BACKGROUND: Sevoflurane, like other halogenated anesthetics, has been shown to have a protective effect on the myocardium at risk after an ischemic injury. The current study tested the hypothesis that such beneficial effects, so far mainly seen in the laboratory, are reproducible in humans. METHODS: After institutional review board approval, 20 patients scheduled to undergo elective off-pump coronary artery bypass surgery were randomized to receive general anesthesia with either sevoflurane or propofol. Except for this, anesthetic and surgical management was the same in both groups. For assessing myocardial injury, troponin I and myocardial fraction of creatine kinase were determined during the first 24 postoperative hours. Systemic hemodynamic variables were measured before, during, and after completion of coronary artery bypass. RESULTS: Troponin I concentrations increased significantly more in propofol-anesthetized patients than in patients anesthetized with sevoflurane. CONCLUSION: Patients receiving sevoflurane for off-pump coronary artery surgery had less myocardial injury during the first 24 postoperative hours than patients receiving propofol. The results further support cardioprotective effects of sevoflurane.     

The effect of halothane, isoflurane, sevoflurane and propofol infusion on renal function after coronary artery bypass surgery

Renal insufficiency after cardiac surgery is associated with increased mortality, morbidity, and length of stay in the intensive care unit. We investigated the effect of isoflurane, halothane, sevoflurane and propofol anesthesia on perioperative renal function following elective coronary artery surgery. The medical records of 224 patients, in the Hacettepe University Medical Faculty Hospital who had undergone cardiac surgery in one year, were retrospectively reviewed. 65 (29%) patients received isoflurane, 68 (30%) patients received halothane, 64 (29%) patients received sevoflurane, and 27 (12%) patients received propofol infusion as part of maintenance anesthesia for coronary artery bypass surgery. Patient characteristics (age, sex, preoperative ejection fraction), operative data (duration of CPB, duration of operation, number of distal anastomoses, usage of diuretic, intraoperative crystalloid and blood transfusion), intraoperative urinary output, preoperative and postoperative (6th hours and 24th hours) BUN and plasma creatinine levels, were not statistically significant between and within groups. Intraoperative inotropic agent (dopamine) was used in 8 (12.3%) patients in the isoflurane group, in 10 (14.7%) patients in the halothane group, in 11 (17.2%) patients in sevoflurane group and in 9 (33.3%) patients in the propofol group. Postoperatively fluid and blood transfusion, postoperative drainage, urinary output, diuretic usage were smiliar between the four groups (p>0,05). Inotropic agent was used in 8 (12.3%) patients in the isoflurane group, in 9 (13.2%) patients in the halothane group, in 16 (25%) patients in the sevoflurane group and in 7 (25.9%) patients in the propofol group. It is concluded that, halothane, isoflurane, sevoflurane and propofol infusion anesthesia as part of anesthesia maintenance for elective coronary artery bypass surgery does not affect early postoperative renal functions.     

Comparison of two different anesthesia regimens in patients undergoing aortocoronary bypass grafting surgery: sufentanil-midazolam versus remifentanil-propofol

OBJECTIVE: To compare intraoperative hemodynamics and depth of anesthesia using sufentanil-midazolam (SM) versus remifentanil-propofol (RP) anesthesia. DESIGN: Prospective, randomized study. SETTING: Clinical investigation in an urban, university-affiliated hospital. PARTICIPANTS: Forty patients undergoing elective first-time coronary artery bypass graft surgery. Interventions: Twenty patients were anesthetized using SM and 20 patients using RP. MEASUREMENTS AND MAIN RESULTS: Hemodynamic monitoring included a 5-lead electrocardiogram, a radial artery catheter, and a pulmonary artery catheter. Depth of anesthesia was assessed using bispectral index (BIS). Data were obtained after induction of anesthesia (T1), after sternotomy (T2), after pericardiotomy (T3), 5 minutes after cardiopulmonary bypass (CPB) (T4), after closure of thorax (T5), and at the end of surgery (T6). The 2 groups were comparable with regard to demographic and perioperative data. There were no significant differences of any hemodynamic parameter at any time between the 2 groups. In both groups, systemic vascular resistance increased at T2 and decreased at T4 from baseline value (p < 0.05). Cardiac index increased at T4 in both groups from baseline value (p < 0.05); 55% of the patients of both groups needed low-dose dobutamine after CPB. During CPB, 40% of the RP patients needed norepinephrine versus 35% of the SM patients. BIS was lower in the RP than in the SM group at T2 and T3 (p < 0.05). BIS values indicating intraoperative awareness were not noted. CONCLUSION: Both anesthesia regimens provided stable hemodynamics and adequate anesthesia in patients undergoing coronary artery bypass graft surgery.     

Sevoflurane metabolite production in a small cohort of coronary artery bypass graft surgery patients

OBJECTIVE: To determine hepatic and renal effects of hexafluoroisopropanol in patients undergoing coronary artery bypass graft surgery under sevoflurane anesthesia. DESIGN: Prospective, clinical comparison. SETTING: University hospital. PARTICIPANTS: Adult patients scheduled for coronary artery bypass graft surgery (n = 56) were divided into 3 groups according to renal function: group 1, patients with normal renal function (plasma creatinine <1.7 mg/dL), subdivided into 2 groups (group 1a and group 1b), and group 2, patients with impaired renal function (plasma creatinine > or = 1.7 mg/dL). INTERVENTIONS: Anesthesia was maintained with fentanyl, 20 microg/kg, and sevoflurane. In group 1a and group 2, sevoflurane dosage was 0.5 minimum alveolar concentration (MAC). In group 1b, it was 1.0 MAC of sevoflurane. During cardiopulmonary bypass, the same concentration of sevoflurane was given through a membrane oxygenator. MEASUREMENTS AND MAIN RESULTS: Serum hexafluoroisopropanol concentration was measured before induction of anesthesia, at the initiation of cardiopulmonary bypass, at the release of the aortic cross-clamp, at the end of cardiopulmonary bypass, at the end of surgery, and on the 1st postoperative day. Blood urea nitrogen, creatinine, 24-hour urinary output, aspartate aminotransferase, alanine aminotransferase, and total bilirubin were measured at preoperative evaluation, at the end of surgery, and on the 1st and 3rd postoperative days. The levels of hexafluoroisopropanol increased and peaked on the 1st postoperative day. Laboratory values showed no significant differences among all groups. CONCLUSION: The serum level of hexafluoroisopropanol after 0.5 MAC of sevoflurane anesthesia does not aggravate hepatic and renal functions.     

Sevoflurane Provides Greater Protection of the Myocardium than Propofol in Patients Undergoing Off-pump Coronary Artery Bypass Surgery

Background: Sevoflurane, like other halogenated anesthetics, has been shown to have a protective effect on the myocardium at risk after an ischemic injury. The current study tested the hypothesis that such beneficial effects, so far mainly seen in the laboratory, are reproducible in humans.

Methods: After institutional review board approval, 20 patients scheduled to undergo elective off-pump coronary artery bypass surgery were randomized to receive general anesthesia with either sevoflurane or propofol. Except for this, anesthetic and surgical management was the same in both groups. For assessing myocardial injury, troponin I and myocardial fraction of creatine kinase were determined during the first 24 postoperative hours. Systemic hemodynamic variables were measured before, during, and after completion of coronary artery bypass.

Results: Troponin I concentrations increased significantly more in propofol-anesthetized patients than in patients anesthetized with sevoflurane.     

舒芬太尼在非体外循环冠脉搭桥术应用中的临床研究

目的 观察舒芬太尼在非体外循环冠状动脉搭桥手术应用中的安全性和有效性.方法 择期行OPCABG病人54例,被随机分成两组,舒芬太尼组和芬太尼组,每组27例,麻醉诱导应用丙泊酚1 mg/ks～2 ms/ks,同时分别静注舒芬太尼0.5 μg/ks～1μg/kg,或芬太尼4 μg/ks-8 μg/ks,同时吸入安氟醚维持麻醉,持续输注舒芬太尼0.08 μg·ks-1min-1,或芬太尼0.6 μg·ks-1·min-1.记录各组气管插管、切片、麻醉维持和拨除气管导管各时间的收缩压和舒张压.结果 在气管插管过程中,浅麻醉反应的病人数舒芬太尼组明显低于芬太尼组,在气管插管切皮,麻醉维持和拔管期间,芬太尼组收缩压、舒张压明显高于舒芬太尼组,术后清醒和拔管时间两组病人无统计学差异.结论 舒芬太尼的麻醉效果优于芬太尼,舒芬太尼能提供术中更稳定的血液动力学.     

Vital capacity inhalation induction with sevoflurane: an alternative to standard intravenous induction for patients undergoing cardiac surgery

OBJECTIVE: To determine the respiratory and cardiovascular effects of a high concentration vital capacity induction with sevoflurane compared with an intravenous induction with etomidate in patients scheduled for elective coronary artery bypass graft (CABG) surgery. DESIGN: Prospective, randomized, double-blind, controlled clinical trial. SETTING: Cardiothoracic unit at a university hospital referral center. PARTICIPANTS: Twenty-two patients undergoing elective CABG surgery. INTERVENTIONS: The study group (group S) received a vital capacity gaseous induction with sevoflurane 8% (n = 12) and the control group (group E) were given etomidate, 0.2 to 0.3 mg/kg (n = 10). Anesthesia was supplemented with fentanyl, 8 microg/kg, and vecuronium, 0.1 mg/kg, in both groups. MEASUREMENTS AND MAIN RESULTS: The speed of induction of anesthesia was comparable between the groups. There was a significant increase in minute ventilation after induction of anesthesia in both groups. This increase was associated with a small reduction in PaCO2. There were no clinically significant changes in pH and PaO(2). The incidence of breath-holding and the need for an oropharyngeal airway were similar between the groups. Both groups had similar reductions in mean arterial pressure and cardiac output during the study period; however, a downward trend in mean pulmonary artery pressure was noted in group S, whereas in group E it remained unchanged. Absolute plasma epinephrine and norepinephrine values were low during the precardiopulmonary bypass period in both groups. CONCLUSIONS: The technique of vital capacity inhalation induction with 8% sevoflurane offers a rapid onset of anesthesia, satisfactory airway control, and a good hemodynamic profile. Consideration should be given to the benefits of single-agent anesthesia and lowered pulmonary artery pressure during the precardiopulmonary bypass period. In addition to CABG surgery, this technique could be considered in patients with coronary artery disease undergoing noncardiac surgery, particularly for procedures in which spontaneous ventilation is preferred.     

Time to tracheal extubation after coronary artery surgery with isoflurane, sevoflurane, or target-controlled propofol anesthesia: a prospective, randomized, controlled trial

OBJECTIVES: To determine if anesthesia with sevoflurane or target-controlled propofol reduced the time to tracheal extubation after coronary artery bypass graft surgery compared with isoflurane anesthesia. DESIGN: A 3-arm (isoflurane, sevoflurane, or propofol), randomized, controlled trial with patients and intensive care staff blinded to the drug allocation. SETTING: A single, tertiary referral hospital affiliated with the University of Melbourne. PARTICIPANTS: Three hundred sixty elective coronary artery surgery patients. INTERVENTIONS: Patients received either isoflurane (control group, 0.5%-2% end-tidal concentration), sevoflurane (1%-4% end-tidal concentration), or target-controlled infusion of propofol (1-8 microg/mL plasma target concentration) as part of a balanced, standardized anesthetic technique including 15 microg/kg of fentanyl. MEASUREMENTS AND MAIN RESULTS: The primary outcome was time to tracheal extubation. The median time to tracheal extubation for the propofol group was 10.25 hours (interquartile range [IQR] 8.08-12.75), the sevoflurane group 9.17 hours (IQR 6.25-11.25), and the isoflurane group 7.67 hours (IQR 6.25-9.42). Intraoperatively, the propofol group required less vasopressor (p = 0.002) and more vasodilator therapy (nitroglycerin p = 0.01, nitroprusside p = 0.002). There was no difference among the groups in time to intensive care unit discharge. CONCLUSIONS: The median time to tracheal extubation was significantly longer for the target-controlled propofol group. A significantly greater number in this group required the use of a vasodilator to control intraoperative hypertension.     

七氟醚对老年冠心病患者胃癌根治术的心肌保护作用

目的比较老年冠心病患者胃癌根治术中七氟醚和丙泊酚麻醉的心肌保护作用。方法择期行胃癌根治手术患者40例,ASAⅡ或Ⅲ级,年龄65～85岁,随机均分为丙泊酚复合瑞芬太尼组(P组)和七氟醚复合瑞芬太尼组(S组)。记录术中血管活性药物使用情况。分别于术前、术后即刻、术后6、12、24h抽取中心静脉血测定血清心肌肌钙蛋白I(cTnI)和肌酸激酶同工酶(CK-MB)浓度。结果两组血管活性药物使用情况差异无统计学意义。术后6、12、24hS组CK-MB、cTnI浓度明显低于P组(P<0.05)。结论七氟醚复合瑞芬太尼比丙泊酚复合瑞芬太尼麻醉对老年冠心病患者行胃癌根治术具有更好的心肌保护效果。     

Impact of bispectral index monitoring on stress response and propofol consumption in patients undergoing coronary artery bypass surgery

BACKGROUND: Bispectral Index (BIS)-titrated administration allows a reduction of propofol infusion rates in patients undergoing surgery. Resulting differences in anesthetic depth might affect the stress response to surgery involving neural circuitry not reflected in the electroencephalogram. METHODS: Forty patients scheduled to undergo elective coronary artery bypass grafting receiving a background infusion of remifentanil (0.3 microg . kg . min) were anesthetized with intravenous propofol delivered by target-controlled infusion according to the Marsh pharmacokinetic model under BIS monitoring. In a randomized, prospective design, 20 patients received propofol at a target concentration of 3 microg/ml, whereas in 20 patients propofol was titrated to maintain a BIS value of 40-50. Plasma concentrations of propofol (by means of gas chromatography-mass spectrometry), epinephrine, norepinephrine (by means of high-pressure liquid chromatography), cortisol (by means of radioimmunoassay), and interleukins 6 and 10 (by means of enzyme-linked immunosorbent assay) were measured repeatedly throughout surgery. RESULTS: BIS monitoring allowed a 30% reduction of propofol infusion rates and a similar decrease in plasma propofol concentrations in the BIS group without affecting the stress response to surgery for the group mean. None of the patients reported awareness during a standardized interview. Interestingly, propofol-remifentanil anesthesia blunted the release of epinephrine and cortisol to bypass surgery completely even when the propofol infusion rate was reduced according to BIS values. CONCLUSIONS: Total intravenous anesthesia using propofol-remifentanil effectively attenuates the neurohumoral stress response to coronary bypass surgery involving cardiopulmonary bypass. Titration of propofol using BIS allows for significant reduction of propofol consumption, with only minor effects on stress response under these conditions.     

Incidence of atrial fibrillation early after cardiac surgery: can choice of the anesthetic regimen influence the incidence?

Occurrence of atrial fibrillation is a common complication after coronary surgery. This study aimed to identify the perioperative factors that are associated with its occurrence with specific attention to the possible influence of the choice of the anesthetic regimen after elective coronary surgery. A retrospective chart analysis was performed in 460 patients who underwent elective coronary artery surgery with cardiopulmonary bypass using the standard institutional anesthetic, surgical and postoperative protocols. The only difference in management was the choice of the primary anesthetic regimen. 110 patients had a total intravenous anesthesia with propofol, 90 patients had a total intravenous anesthesia with midazolam, 150 patients were anesthetized with sevoflurane and 110 patients with desflurane. The primary outcome variable was the incidence of atrial fibrillation within the first 24 postoperative hours. Atrial fibrillation occurred in 64 of the 460 patients included (13.9%). Multiple logistic regression analysis identified increased age (> 70 years), EuroSCORE > 4, prolonged CPB time (> 100 min) and need for prolonged inotropic support (> 6 hours) as the significant independent risk factors for the occurrence of postoperative atrial fibrillation. The incidence of postoperative atrial fibrillation differed among the different anesthetic groups with the lowest incidence in the sevoflurane group (propofol: 17/110; midazolam: 15/90; sevoflurane: 9/150; desflurane: 23/110) (p = 0.004). This finding should be further confirmed in a prospective sufficiently powered multicenter study.     

Electroencephalogram bispectral index predicts hemodynamic and arousal reactions during induction of anesthesia in patients undergoing cardiac surgery

OBJECTIVE: To evaluate hemodynamic and clinical responses to induction of anesthesia and intubation at 3 different values of the electroencephalogram bispectral index (BIS). DESIGN: Prospective randomized trial. SETTING: University-affiliated hospital. PARTICIPANTS: Forty-five patients undergoing elective coronary artery bypass graft surgery. INTERVENTIONS: Patients were assigned to 3 groups (n = 15 for each group). Anesthesia was induced with midazolam, sufentanil, and pancuronium. In each group, sufentanil was titrated to a BIS value of 60, 50, or 40 before intubation. Mean arterial blood pressure, heart rate, incidence of coughing, tearing, and need for fluid replacement or injections of norepinephrine were recorded before intubation as well as immediately and 1 and 2 minutes after intubation. MEASUREMENTS AND MAIN RESULTS: Thirteen patients intubated at a BIS value of 60 coughed and 14 experienced tearing after intubation, whereas no patient of the other groups showed signs of arousal. Mean arterial blood pressure remained stable in the BIS 60 and 50 groups, whereas in the BIS 40 group it decreased significantly to lower values before and after intubation. Patients in the BIS 40 group needed significantly more fluid replacement and injections of norepinephrine compared with the other groups. No significant changes in heart rate were detected. CONCLUSIONS: Electroencephalogram BIS predicts hemodynamic and arousal reaction resulting from induction of anesthesia and endotracheal intubation. BIS value should be kept at 50 before intubation to ensure safe hemodynamic conditions during induction of anesthesia in cardiac surgical patients.     

The influence of propofol versus sevoflurane anesthesia on outcome in 10,535 cardiac surgical procedures

OBJECTIVE: The purpose of this study was to evaluate the possible cardioprotective effect of sevoflurane versus propofol anesthesia in patients undergoing cardiac surgery. METHODS: Ten thousand five hundred thirty-five consecutive single cardiac surgical procedures from 3 cardiac centers were reported to a common registry from 1999 to 2005. The registry was established by the National Board of Health, and reporting was obligatory for all public heart centers in Denmark. The patients were stratified according to preoperative risk factors (EuroSCORE parameters). The outcome parameters were 30-day mortality, the incidence of postoperative myocardial infarction, and the incidence of postoperative arrhythmias. RESULTS: Overall, the 30-day mortality was lower after sevoflurane (2.84%) versus propofol (3.30%), although not significantly so (p = 0.18). No difference was found in the incidence of postoperative myocardial infarction (sevoflurane, 7.76%/propofol, 7.47%). Patients with preoperative unstable angina and/or recent myocardial infarction, and thus already "preconditioned," did not show any difference in mortality between anesthetic groups, whereas patients without these predictors showed a lower postoperative mortality after sevoflurane (2.28% v 3.14%, p = 0.015), which can at least partly be explained by a preconditioning-like effect. The data suggest that patients suffering relatively severe preoperative ischemic stress benefited from propofol anesthesia, which can be related to the antioxidant effects of propofol. Patients in the sevoflurane group had a higher incidence of postoperative atrial fibrillation (28.75% v 24.87%, p < 0.001), whereas patients in the propofol group showed a higher incidence of all other arrhythmias. CONCLUSION: Sevoflurane and propofol both possess some, although different, cardioprotective properties. Sevoflurane appears to be superior to propofol in patients with little or no ischemic heart disease, such as noncoronary artery bypass graft (CABG) surgery and CABG surgery without severe preoperative ischemia, whereas propofol seems superior in patients with severe ischemia, cardiovascular instability, or in acute/urgent surgery.     

Changes in plasma creatinine concentration after cardiac anesthesia with isoflurane, propofol, or sevoflurane: a randomized clinical trial

BACKGROUND: Renal impairment often follows cardiac surgery. The authors investigated whether sevoflurane produces greater increases in plasma creatinine concentration than isoflurane or propofol after elective coronary artery surgery. METHODS: As part of maintenance anesthesia, including during cardiopulmonary bypass, patients were randomly allocated to receive one of three agents: isoflurane (n = 118), sevoflurane (n = 118), or propofol (n = 118). Fresh gas flows were 3 l/min. The preoperative plasma creatinine concentration was subtracted from the highest creatinine concentration in the first 3 postoperative days. A median maximum increase greater than 44 microM (0.5 mg/dl) was regarded as clinically important. Data were analyzed on an intention-to-treat basis. Subgroup analyses were performed on per-protocol patients and those with preoperative renal impairment (creatinine concentration > 130 microM [1.47 mg/dl] or urea > 7.7 mM [blood urea nitrogen, 21.6 mg/dl]). RESULTS: The differences between the groups were small, clinically unimportant, and not statistically significant for the primary analysis and subgroups. The proportions of patients with creatinine increases greater than 44 microM were 15% in the isoflurane group, 17% in the sevoflurane group, and 11% in the propofol group (P = 0.45). The median increases were 8 microM in the isoflurane group, 4 microM in the sevoflurane group, and 6 microM in the propofol group. The differences between the three median maximum increases were 1-4 microM (P > 0.45). In the subgroup with preoperative renal impairment, the median increases were 10 microM in the isoflurane group, 15 microM in the sevoflurane group, and 5 microM in the propofol group (P = 0.72). CONCLUSIONS: Sevoflurane did not produce greater increases in creatinine than isoflurane or propofol after elective coronary artery surgery.     

General anesthesia by propofol infusion for delivery by cesarean section compared with sevoflurane anesthesia using bispectral index (BIS) monitoring

BACKGROUND: We compared the postoperative effects of propofol and sevoflurane used for anesthesia during elective cesarean section, using bispectral index (BIS) monitoring. METHODS: Fourteen parturients were randomized into two groups (Propofol group; P group, Sevoflurane group; S group). All patients received thiopental and suxamethonium for induction and had orotracheal intubation in rapid sequence. All patients received 1% sevoflurane until delivery. In the P group, sevoflurane was stopped after delivery and propofol infusion was started, to achieve target BIS values below 60; the infusion rate was 6. 17 +/- 0.98 mg x kg(-1) x h(-1). Patients in the S group received 1% sevoflurane. All patients were given fentanyl and vecuronium as required. RESULTS:There were no significant differences between the two groups in their times for beginning drinking, walking, eating or removal of urinary catheters after the operations. There were no significant differences in total blood loss or intraoperative dose of oxytocin, but postoperative and total doses of oxytocin were significantly higher in those in the P group. CONCLUSIONS: Comparing the effects of propofol and sevoflurane on the postoperative condition of parturients, no differences could be detected. We can choose to use propofol instead of sevoflurane for cesarean section.     

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.     

Propofol and sufentanil titration with the bispectral index to provide anesthesia for coronary artery surgery

BACKGROUND: To provide anesthesia for cardiac surgery, hypnotics and opioids are frequently titrated on variables such as mean arterial pressure and heart rate. In this study conducted in patients scheduled to undergo coronary artery bypass grafting, propofol and sufentanil, both administered by computer-controlled infusion, were titrated on the Bispectral Index (BIS) values using a predefined algorithm. METHODS: After written informed consent, 110 patients, 95 men and 15 women aged 61 (9) yr [mean (SD)], were randomly allocated to receive predicted sufentanil effect site concentrations (Ce) of 0.5, 0.75, 1, 1.25, and 1.5 ng/ml, decreased by a third after sternotomy (groups 1-5). Target induction propofol concentration was 1.5 microg/ml and subsequently adjusted on BIS values. The following parameters were recorded: BIS values, predicted propofol Ce, the number of changes of propofol target, mean arterial pressure, heart rate, the number of bolus injection and doses of vasoconstrictor and vasodilator drugs, time to tracheal extubation, postoperative awareness and satisfaction scores, and cumulative morphine doses for the first postoperative day. RESULTS: One patient randomized to group 1 required 0.75 ng/ml sufentanil Ce instead of 0.5 ng/ml for increased BIS values on tracheal intubation. BIS values were similar in the five groups. The predicted propofol Ce values were different (P < 0.05; analysis of variance) among the five groups: 1.59 (0.47) to 1.23 (0.25) microg/ml in group 1 and group 4, respectively. Significantly fewer changes of propofol target were required in group 4 as compared to group 1. There were no differences among the five groups for mean arterial pressure, heart rate, time to tracheal extubation, awareness, satisfaction scores, and morphine requirements. CONCLUSION: These results suggest the BIS, as part of an algorithm that uses both the absolute BIS value and its increase following tracheal intubation, can be used to effectively titrate both propofol and sufentanil. A predicted sufentanil Ce of 1.25 ng/ml before and 0.8 ng/ml after sternotomy was associated with the lowest predicted propofol Ce and fewer changes of propofol target. Lower sufentanil concentrations required higher propofol concentrations and more frequent changes of the target propofol concentration and were associated with similar hemodynamic tolerance.     

舒芬太尼复合七氟烷小剂量丙泊酚麻醉在非体外冠脉搭桥术中的应用

目的探讨舒芬太尼复合七氟烷和小剂量丙泊酚静吸复合全麻在非体外循环冠脉搭桥术（off-pump coronary artery bypass graft,OPCABG）中的应用。方法选择符合条件的非体外循环冠脉搭桥手术患者70例,随机分为两组（n=35）,舒芬太尼组（S组）和芬太尼组（F组）,S组予以舒芬太尼、七氟烷复合小剂量的丙泊酚,F组予以芬太尼、七氟烷复合小剂量的丙泊酚进行静吸复合全麻,观察两组插管前（T0）、插管后（T1）、劈胸骨（T2）、搭回旋支（T3）及穿钢丝（T4）时血流动力学的变化。结果两组平均动脉压（MAP）在T1、T2、T4等强刺激时均升高（P〈0.05）,且F组较S组升高更显著（P〈0.05）;两组心率（HR）在T1～T4各时点均显著升高（P〈0.05）,但组间比较无显著性差异（P〉0.05）;两组混合静脉血氧饱和度（SvO2）在T3时均明显降低（P〈0.05）,但组间比较差异无显著性（P〉0.05）;S组血压反应和心率明显波动的发生率明显低于F组（P〈0.05）。结论舒芬太尼、七氟烷复合小剂量丙泊酚静吸复合全麻具有更稳定的血流动力学效应,对病人的循环干扰小,是OPCABG的一个良好的选择。     

Efficacy of bispectral index for anesthetic management of combined off-pump coronary artery bypass grafting and abdominal aortic aneurysm replacement]

A 57-year-old female patient underwent combined off-pump coronary artery bypass grafting and abdominal aortic aneurysm replacement. Anesthesia was maintained with propofol, fentanyl, and thoracic epidural anesthesia. Propofol doses were adjusted to maintain bispectral index (BIS) between 40-60. Despite the remarkable hemodynamic changes, BIS remained stable at about 50 during the surgery. The average dose of propofol was 3.3 mg.kg-1.hr-1. The patient awoke an hour after the surgery and was extubated 1.5 hours thereafter. This case report suggests that BIS is a useful index to determine the depth of anesthesia during surgeries which induce marked hemodynamic changes.