Desflurane and sevoflurane in cardiac surgery: a meta-analysis of randomized clinical trials

OBJECTIVES: The authors performed a meta-analysis to investigate whether the cardioprotective effects of volatile anesthetics translate into decreased morbidity and mortality in patients undergoing cardiac surgery. BACKGROUND: It is commonly believed that the choice of the primary anesthetic agent does not result in different outcomes after cardiac surgery. Recent evidence, however, has indicated that volatile anesthetics improve postischemic recovery at a cellular level, in isolated hearts, in animals, and in humans. METHODS: Four investigators independently searched BioMedCentral and PubMed. Inclusion criteria were random allocation to treatment and comparison of a total intravenous anesthesia regimen versus an anesthesia plan including desflurane or sevoflurane performed on cardiosurgical patients. Exclusion criteria were duplicate publications, nonhuman experimental studies, and no outcome data. The endpoints were the rate of perioperative myocardial infarction and hospital mortality. RESULTS: The search yielded 22 studies, involving 1,922 patients. Volatile anesthetics were associated with significant reductions of myocardial infarctions (24/979 [2.4%] in the volatile anesthetics group v 45/874 [5.1%] in the control arm, odds ratio [OR] = 0.51 [0.32-0.84], p for effect = 0.008, and p for heterogeneity = 0.77) and mortality (4/977 [0.4%] v 14/872 [1.6%], OR = 0.31 [0.12-0.80], p for effect = 0.02, and p for heterogeneity = 0.88). CONCLUSIONS: Desflurane and sevoflurane have cardioprotective effects that result in decreased morbidity and mortality. The present data show for the first time that the choice of an anesthetic regimen based on administration of halogenated anesthetics is associated with a better outcome after cardiac surgery.     

Cardiac protection by volatile anesthetics. A review

All volatile anesthetics have cardiac depressant effects that decrease myocardial oxygen demand and may thus improve the myocardial oxygen balance during ischemia. Recent experimental evidence has clearly demonstrated that, in addition to these indirect effects, volatile anesthetic agents also directly protect from ischemic myocardial damage. Implementation of these effects during clinical anesthesia can provide an additional tool for treatment or prevention of ischemic cardiac dysfunction during the perioperative period. A recent meta-analysis showed that desflurane and sevoflurane reduce postoperative mortality and the incidence of myocardial infarction following cardiac surgery, with significant advantages in terms of postoperative cardiac troponin release, need for inotropic support, and time on mechanical ventilation, as well as in time spent in the intensive care unit and overall hospital stay. Multicenter, randomized clinical trials previously demonstrated that desflurane could reduce the postoperative release of cardiac troponin I, the need for inotropic support, and the number of patients requiring prolonged hospitalization following coronary artery bypass graft surgery, either with or without cardiopulmonary bypass. However, evidence in non-coronary surgical settings is contradictory and will be reviewed in this paper, together with the mechanism of cardiac protection by volatile agents.     

Choice of primary anesthetic regimen can influence intensive care unit length of stay after coronary surgery with cardiopulmonary bypass

BACKGROUND: Volatile anesthetics protect the myocardium during coronary surgery. This study hypothesized that the use of a volatile agent in the anesthetic regimen would be associated with a shorter intensive care unit (ICU) and hospital length of stay (LOS), compared with a total intravenous anesthetic regimen. METHODS: Elective coronary surgery patients were randomly assigned to receive propofol (n = 80), midazolam (n = 80), sevoflurane (n = 80), or desflurane (n = 80) as part of a remifentanil-based anesthetic regimen. Multiple logistic regression analysis was used to identify the independent variables associated with a prolonged ICU LOS. RESULTS: Patient characteristics were similar in all groups. ICU and hospital LOS were lower in the sevoflurane and desflurane groups (P < 0.01). The number of patients who needed a prolonged ICU stay (> 48 h) was also significantly lower (propofol: n = 31; midazolam: n = 34; sevoflurane: n = 10; desflurane: n = 15; P < 0.01). Occurrence of atrial fibrillation, a postoperative troponin I concentration greater than 4 ng/ml, and the need for prolonged inotropic support (> 12 h) were identified as the significant risk factors for prolonged ICU LOS. Postoperative troponin I concentrations and need for prolonged inotropic support were lower in the sevoflurane and desflurane group (P < 0.01). Postoperative cardiac function was also better preserved with the volatile anesthetics. The incidence of other postoperative complications was similar in all groups. CONCLUSIONS: The use of sevoflurane and desflurane resulted in a shorter ICU and hospital LOS. This seemed to be related to a better preservation of early postoperative myocardial function.     

Myocardial damage prevented by volatile anesthetics: a multicenter randomized controlled study

OBJECTIVE: The purpose of this study was to evaluate the effects of volatile anesthesia versus total intravenous anesthesia on cardiac troponin release in off-pump coronary artery bypass grafting (OPCAB). DESIGN: The authors performed a multicenter randomized controlled study to compare cardiac troponin release in patients receiving either volatile anesthetics or total intravenous anesthesia for cardiac surgery on the beating heart, which is an excellent model of human myocardial ischemia. SETTING: Three university hospitals. PARTICIPANTS: The authors randomly assigned 57 patients to desflurane (volatile anesthetic) and 55 patients to propofol (intravenous anesthetic) in addition to an opiate-based anesthesia for OPCAB. INTERVENTIONS: The 2 groups of patients received either desflurane (volatile anesthetic) or propofol in addition to an opiate-based anesthesia for OPCAB. Peak postoperative troponin I release was measured as a marker of myocardial necrosis. Prolonged hospitalization was considered as a secondary outcome. MEASUREMENTS AND MAIN RESULTS: Patient mean age was 69 years, and 82% were men. There was a significant (p < 0.001) reduction in postoperative median (25th-75th percentiles) peak of troponin I in patients receiving volatile anesthetics, 1.2 (0.9-1.9) ng/dL, compared with patients receiving total intravenous anesthesia, 2.7 (2.1-4.0) ng/dL. This myocardial protection resulted in a reduced (p = 0.04) number (percentage) of patients requiring postoperative inotropes, 20 (35%) versus 31 (56%), and a reduced number (percentage) of patients submitted to prolonged hospitalization (> or =7 days), 7 (12%) versus 20 (36%) in the 2 groups (p = 0.005). One patient receiving total intravenous anesthesia died within 30 days of surgery. CONCLUSIONS: Myocardial damage measured by cardiac troponin release could be reduced by volatile anesthetics during OPCAB. Because patients underwent cardiac surgery on the beating heart, these results could have implications for cardiac patients undergoing noncardiac surgery.     

Risk stratification with cardiac troponin I in patients undergoing elective coronary artery bypass surgery.

OBJECTIVE: Cardiac troponin I (cTnI) is a highly sensitive and specific marker for postoperative prediction of patients outcome after coronary artery bypass surgery (CABG). Whether preoperatively elevated cTnI levels similarly predict the outcome in patients scheduled for elective CABG is currently unknown. METHODS: Therefore, a possible correlation between preoperative cTnI levels and perioperative major adverse events and in-hospital mortality after CABG was investigated. CTnI was measured within 24h before surgery in 1405 out of 3124 consecutive elective CABG patients. Out of these patients, 1178 had a preoperative cTnI level below 0.1ng/ml (group 1), 163 patients had a cTnI level between 0.11 and 1.5ng/ml (group 2), and 64 patients had a cTnI level above 1.5ng/ml (group 3). CTnI levels, electrocardiograms, clinical data, adverse events and in-hospital mortality were recorded prospectively. Patients with ST-elevation myocardial infarction less than 7 days before surgery were excluded from the study. RESULTS: Perioperative myocardial infarction (PMI) occurred in 69/1178 patients (5.9%) in group 1, 14/163 patients (8.6%; odds ratio (OR) 1.5, 95% confidence interval (CI): 0.8-2.8) in group 2, and 11/64 patients (17.2%; OR 3.3, CI: 1.6-7.0) in group 3 (overall: P<0.001, Cochran-Armitage trend test). Low cardiac output syndrome (LCOS) occurred in 19/1178 patients (1.6%), 9/163 (5.5%; OR 3.6, CI: 1.5-8.5), and 7/64 patients (10.9%; OR 7.5, CI: 2.7-19.8) (overall: P<0.001, group 1 vs. group 2: P<0.002), respectively. In-hospital mortality was 1.7% in group 1 and 3.1% in group 2, but 6.3% (OR 3.9, CI: 1.1-12.5) in group 3 (overall: P<0.01, group 1 vs. group 2: P=NS). Intensive care and hospital stay were significantly longer in group 3 compared to groups 1 and 2. Univariate and multivariate logistic regression analysis confirmed the statistically significant relationship between cTnI and PMI, LCOS and in-hospital mortality, respectively (P<0.001). CONCLUSIONS: Risk stratification by measurement of cTnI levels within 24h before elective CABG clearly identifies a subgroup of patients with increased risk for postoperative adverse outcome and in-hospital mortality.     

Choice of Primary Anesthetic Regimen Can Influence Intensive Care Unit Length of Stay after Coronary Surgery with Cardiopulmonary Bypass

Background: Volatile anesthetics protect the myocardium during coronary surgery. This study hypothesized that the use of a volatile agent in the anesthetic regimen would be associated with a shorter intensive care unit (ICU) and hospital length of stay (LOS), compared with a total intravenous anesthetic regimen.

Methods: Elective coronary surgery patients were randomly assigned to receive propofol (n = 80), midazolam (n = 80), sevoflurane (n = 80), or desflurane (n = 80) as part of a remifentanil-based anesthetic regimen. Multiple logistic regression analysis was used to identify the independent variables associated with a prolonged ICU LOS.

Results: Patient characteristics were similar in all groups. ICU and hospital LOS were lower in the sevoflurane and desflurane groups (P < 0.01). The number of patients who needed a prolonged ICU stay (> 48 h) was also significantly lower (propofol: n = 31; midazolam: n = 34; sevoflurane: n = 10; desflurane: n = 15; P < 0.01). Occurrence of atrial fibrillation, a postoperative troponin I concentration greater than 4 ng/ml, and the need for prolonged inotropic support (> 12 h) were identified as the significant risk factors for prolonged ICU LOS. Postoperative troponin I concentrations and need for prolonged inotropic support were lower in the sevoflurane and desflurane group (P < 0.01). Postoperative cardiac function was also better preserved with the volatile anesthetics. The incidence of other postoperative complications was similar in all groups.     

Desflurane versus propofol in patients undergoing mitral valve surgery

OBJECTIVE: Myocardial ischemic damage is reduced by volatile anesthetics in patients undergoing coronary artery bypass graft surgery, but it is unknown whether this benefit exists in patients undergoing valvular surgery with ischemia-reperfusion injury related to cardioplegic arrest and cardiopulmonary bypass. This study compared cardiac troponin release in patients receiving either volatile anesthetics or total intravenous anesthesia for mitral valve surgery. DESIGN: Randomized controlled study. SETTING: University hospital. PARTICIPANTS: One hundred twenty patients undergoing mitral valve surgery. Interventions: Fifty-nine patients received the volatile anesthetic desflurane for 30 minutes before cardiopulmonary bypass, whereas 61 patients received a total intravenous anesthetic with propofol. All patients had an opioid-based anesthetic for the mitral valve surgery. MEASUREMENTS AND MAIN RESULTS: Peak postoperative troponin I release was measured as a marker of myocardial necrosis after mitral valve surgery. Patient mean age was 60 years, and 54% were men. There was no significant (p = 0.7) reduction in median (25th-75th percentiles) postoperative peak troponin, 11.0 (7.5-17.4) ng/dL in the desflurane group versus 11.5 (6.9-18.0) ng/dL in the propofol group. A subgroup of patients with concomitant coronary artery disease had the expected reduction (p = 0.02) of peak troponin I in those receiving desflurane, 14.0 (9.7-17.3) ng/dL, when compared with patients receiving total intravenous anesthesia, 31.6 (15.7-52.0) ng/dL. CONCLUSIONS: Myocardial damage measured by cardiac troponin release was not reduced by volatile anesthetics in patients undergoing mitral valve surgery, whereas it was reduced in patients with concomitant coronary artery disease.     

Sevoflurane versus desflurane for early postoperative vomiting after general anesthesia in hospitalized adults: A systematic review and meta-analysis of randomized controlled trials

Study objectiveThis systematic review and meta-analysis aimed at assessing the effects of two commonly used anesthetics in general anesthesia (GA), sevoflurane and desflurane, on early postoperative vomiting (POV) in hospitalized adults.DesignSystematic review and meta-analysis of randomized controlled trials (RCTs).SettingEarly postoperative vomiting after GA.PatientsA total of 266 adult patients receiving inpatient surgeries under GA maintained with sevoflurane or desflurane.InterventionsWe searched PubMed, Medline, Cochrane Central Register of Controlled Trials, ScienceDirect, and Embase for eligible RCTs comparing postoperative outcomes following sevoflurane- or desflurane-maintained anesthesia.MeasurementsThe primary outcome was early POV. Secondary outcomes included late POV, early and late postoperative nausea (PON), time to extubation, and emergence time.Main resultsEight trials were included. There was no significant difference in the risk of early POV (risk ratio [RR] 1.03, 95% confidence interval [CI] 0.64–1.64, p = 0.91). No significant difference in early PON was observed (RR 1.09; 95% CI, 0.77–1.56; p = 0.62). Nevertheless, the incidence of late POV and late PON were significantly lower in the sevoflurane group than that in the desflurane group (RR 0.47, 95% CI 0.23–0.94, p = 0.03; RR 0.45, 95% CI 0.24–0.84, p = 0.01, respectively). The extubation time was longer in the sevoflurane group than in the desflurane group (standardized mean difference [SMD] 0.56, 95% CI 0.14–0.97, p = 0.009). The emergence time of patients in the sevoflurane group was longer than that in those receiving desflurane (SMD 0.76, 95% CI 0.1–1.42, p = 0.02).ConclusionsDesflurane had the same effects on early POV and early PON as sevoflurane. However, the association between late POV and late PON with desflurane was stronger than that with sevoflurane if the effects of opioids were not considered. The desflurane group had shorter time to extubation and emergence time than the sevoflurane group. PROSPERO registration number: CRD42020218988.     

The effect of sevoflurane versus desflurane on the incidence of upper respiratory morbidity in patients undergoing general anesthesia with a Laryngeal Mask Airway: a meta-analysis of randomized controlled trials

Study ObjectiveTo compare the incidence of upper airway morbidity with sevoflurane versus desflurane in patients undergoing general anesthesia with a Laryngeal Mask Airway (LMA).DesignSystematic review and meta-analysis of randomized controlled trials (RCTs).SettingOperating room of an academic medical center.MeasurementsA systematic review of RCTs of patients receiving general anesthesia with a LMA was performed. Sevoflurane and desflurane were used for maintenance of anesthesia in the RCTs. A wide search was performed to identify RCTs comparing desflurane with sevoflurane on the incidence of upper respiratory adverse events in patients undergoing surgery with a LMA. The primary outcomes were incidence of cough and laryngospasm. A random-effects model was used to perform quantitative analysis.Main ResultsData originating from 7 studies comprising 657 subjects were analyzed. The confidence interval (CI) was large relative to a clinically significant difference in the incidence of overall cough and laryngospasm in patients receiving desflurane versus sevoflurane (odds ratio [OR; 95% CI] of 1.44 [0.49 - 4.1] and 3.06 [0.43 - 21.62]), respectively. The incidence of cough at emergence was greater in subjects receiving desflurane compared with sevoflurane (OR [95% CI] of 2.43 [1.2 - 4.7], number needed to harm [NNH] = 9.0); however, the analysis was limited by the presence of an asymmetric funnel plot suggesting the possibility of publication bias.ConclusionsThere is a lack of evidence that desflurane causes a greater incidence of upper airway adverse events than sevoflurane in patients undergoing general anesthesia with a LMA.     

Volatile Anästhetika

None of the currently available inhaled anesthetics has all of the properties of an "ideal" inhaled agent. The exceptionally low solubility of desflurane and sevoflurane offers a significantly greater precision of control over maintenance of anesthesia and a potential for a more rapid recovery from anesthesia than other inhaled anesthetics. Sevoflurane appears to offer some advantages regarding cardiovascular stability. Products of metabolism or degradation can be associated with potential organ-specific toxic effects. Renal toxicity is discussed for enflurane and sevoflurane. Breakdown products of volatile agents with carbon dioxide absorbents have to be mentioned especially for sevoflurane (compound A) and desflurane (CO). In contrast to intravenous anesthetics, volatile anesthetics are associated with cardio- and cerebroprotection.     

In Vitro Effects of Desflurane, Sevoflurane, Isoflurane, and Halothane in Isolated Human Right Atria

Background: Direct myocardial effects of volatile anesthetics have been studied in various animal species in vitro. This study evaluated the effects of equianesthetic concentrations of desflurane, sevoflurane, isoflurane, and halothane on contractile parameters of isolated human atria in vitro.

Methods: Human right atrial trabeculae, obtained from patients undergoing coronary bypass surgery, were studied in an oxygenated (95% O2-5% CO2) Tyrode's modified solution ([Ca2+]o = 2.0 mM, 30[degrees]C, stimulation frequency 0.5 Hz). The effects of equianesthetic concentrations (0.5, 1, 1.5, 2, and 2.5 minimum alveolar concentration [MAC]) of desflurane, sevoflurane, isoflurane, and halothane on inotropic and lusitropic parameters of isometric twitches were measured.

Results: Isoflurane, sevoflurane, and desflurane induced a moderate concentration-dependent decrease in active isometric force, which was significantly lower than that induced by halothane. In the presence of adrenoceptor blockade, the desflurane-induced decrease in peak of the positive force derivative and time to peak force became comparable to those induced by isoflurane. Halothane induced a concentration-dependent decrease in time to half-relaxation and a contraction-relaxation coupling parameter significantly greater than those induced by isoflurane, sevoflurane and desflurane.     

Minimum alveolar anesthetic concentration of volatile anesthetics in normal and cardiomyopathic hamsters

Minimum alveolar anesthetic concentrations (MAC) values of volatile anesthetics in cardiovascular diseases remain unknown. We determined MAC values of volatile anesthetics in spontaneously breathing normal and cardiomyopathic hamsters exposed to increasing (0.1%-0.3% steps) concentrations of halothane, isoflurane, sevoflurane, or desflurane (n = 30 in each group) using the tail-clamp technique. MAC values and their 95% confidence interval were calculated using logistic regression. In normal hamsters, inspired MAC values were: halothane 1.15% (1.10%-1.20%), isoflurane 1.62% (1.54%-1.69%), sevoflurane 2.31% (2.22%-2.40%), and desflurane 7.48% (7.30%-7.67%). In cardiomyopathic hamsters, they were: halothane 0.89% (0.83%-0.95%), isoflurane 1.39% (1.30%-1.47%), sevoflurane 2.00% (1.85%-2.15%), and desflurane 6.97% (6.77%-7.17%). Thus, MAC values of halothane, isoflurane, sevoflurane, and desflurane were reduced by 23% (P < 0.05), 14% (P < 0.05), 13% (P < 0.05), and 7% (P < 0.05), respectively in cardiomyopathic hamsters. IMPLICATIONS: Minimum alveolar anesthetic concentrations of volatile anesthetics were significantly lower in cardiomyopathic hamsters than in normal hamsters.     

吸入麻醉药对冠脉搭桥术心肌保护作用的Meta分析

目的 评价吸入麻醉药对冠状动脉搭桥术(CABG)心肌缺血-再灌注损伤的保护作用.方法 检索Medline和中国期刊全文数据库,收集各研究中的心脏指数、使用正性肌力药的例数和术后24 h内心肌肌钙蛋白I(cTnI)的最高数值.计数资料采用优势比(OR)和95%可信区间(CI)表示.计量资料用加权平均差(WMD)和95%可信区间表示,统计分析用Revman 4.2.10软件完成.结果 符合标准的文献共23篇,1398例患者.分析显示,吸入麻醉约都能使CABG患者术后的心脏指数增加[WMD=0.41;95%CI(0.17,0.64)],使cTnI明显降低[WMD=-1.61;95%CI(-2.25,-0.96)],需用正性肌力药的患者数减少[OR=0.45;95%CI(0.35,0.58)].结论 七氟醚等吸入麻醉药用于CABG具有明显的心肌保护作用.     

A meta-analysis of the utility of pre-operative brain natriuretic peptide in predicting early and intermediate-term mortality and major adverse cardiac events in vascular surgical patients

We conducted a meta-analysis of the utility of pre-operative B-type natriuretic peptide (BNP) and N-terminal-pro B-type natriuretic peptide in predicting early (< 30 days) and intermediate (< 180 days) term mortality and major adverse cardiac events (cardiac death and nonfatal myocardial infarction) in patients following vascular surgery. A Pubmed Central and EMBASE search was conducted up to January 2008. Of 81 studies identified, seven prospective observational studies were included in the meta-analysis representing five patient cohorts: early outcomes (504 patients) and intermediate-term outcomes (623 patients). A B-type natriuretic peptide or N-terminal-pro B-type natriuretic peptide above the optimal discriminatory threshold determined by receiver operating characteristic curve analysis was associated with 30-day cardiac death (OR 7.6, 95% CI 1.33-43.4, p = 0.02), nonfatal myocardial infarction (OR 6.24, 95% CI 1.82-21.4, p = 0.004) and major adverse cardiac events (OR 17.37, 95% CI 3.31-91.15, p = 0.0007), and intermediate-term, all-cause mortality (OR 3.1, 95% CI 1.85-5.2, p < 0.0001), nonfatal myocardial infarction (OR 2.95, 95% CI 1.17-7.46, p = 0.02) and major adverse cardiac events (OR 3.31, 95% CI 2.1-5.24, p < 0.00001). B-type natriuretic peptide and N-terminal-pro B-type natriuretic peptide are potentially useful pre-operative prognostic tests in vascular surgical patients.     

Cardiac troponin I release after open heart surgery: a marker of myocardial protection?

Background. Unlike creatine kinase MB isoenzyme, cardiac troponin I (cTnI) is a highly specific marker of myocardial injury. Its release has recently been studied after coronary artery bypass grafting operation. However, its significance after open heart surgery (OHS) remains to be determined. This protein release could be a marker of myocardial protection. We sought to study cTnI release after OHS in patients with normal coronary arteries and to compare it with cTnI release in patients after coronary artery bypass graft (CABG) surgery.

Methods. Eighty-five patients undergoing OHS and 86 patients undergoing CABG were enrolled in the study. CTnI concentrations were measured in serial venous blood samples drawn before surgery and immediately, 12 hours, 24 hours, 48 hours, and 5 days after aortic unclamping.

Results. In the OHS group and in the CABG group without acute myocardial infarction (AMI), cTnI peaked at 12 hours postoperatively (6.35 ± 6.5 and 5.38 ± 8.55 ng/mL, respectively) and normalized on day 5 postoperatively (0.57 ± 2 and 0.72 ± 1.62 ng/mL, respectively). CTnI concentration did not differ significantly between the OHS group and the CABG group in the absence of AMI for any samples considered. In the CABG group, 2 patients had AMI. In the OHS group, cTnI levels at 12 hours postoperatively were found to correlate closely with CPB and aortic cross-clamping (ACC) times, contrary to the CABG group, which correlated only with occurrence of AMI. CTnI release was independent of age and ejection fraction in either group.

Conclusions. cTnI release in patients after OHS with normal coronary arteries has the same profile as cTnI release in patients after CABG in the absence of AMI. However, its peak at 12 hours postoperatively is only correlated to ACC and CPB times, which is contrary to cTnI release after CABG surgery. This observation suggests that cTnI could be a marker of myocardial ischemia after OHS.     

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.     

Cardioprotective properties of sevoflurane in patients undergoing aortic valve replacement with cardiopulmonary bypass

In coronary surgery patients the use of a volatile anesthetic regimen with sevoflurane was associated with a better recovery of myocardial function and less postoperative release of troponin I. In the present study we investigated whether these cardioprotective properties were also apparent in the cardiac surgical setting of aortic valve replacement (AVR) surgery for the correction of aortic stenosis. Thirty AVR surgery patients were randomly assigned to receive either target-controlled infusion of propofol or inhaled anesthesia with sevoflurane. Cardiac function was assessed perioperatively using a pulmonary artery catheter. Perioperatively, a high-fidelity pressure catheter was positioned in the left ventricle. Postoperative concentrations of cardiac troponin I were followed for 48 h. After cardiopulmonary bypass (CPB), stroke volume and dP/dt(max) were significantly higher in the patients with sevoflurane. Post-CPB, the effects of an increase in cardiac load on dP/dt(max) were similar to pre-CPB in the sevoflurane group (1.0 % +/- 5.4% post-CPB versus 1.3% +/- 8.6% pre-CPB) but more depressed in the propofol group (-8.2% +/- 4.4% post-CPB versus 0.1% +/- 4.9% pre-CPB). The rate of relaxation was significantly slower post-CPB in the propofol group. Postoperative levels of troponin I were significantly lower in the sevoflurane group. Our data indicate that the use of a volatile anesthetic regimen in AVR surgery was associated with better preservation of myocardial function and a reduced postoperative release of troponin I.     

Absence of bronchodilation during desflurane anesthesia: a comparison to sevoflurane and thiopental

BACKGROUND: Bronchospasm is a potential complication in anyone undergoing general anesthesia. Because volatile anesthetics relax bronchial smooth muscle, the effects of two newer volatile anesthetics, desflurane and sevoflurane, on respiratory resistance were evaluated. The authors hypothesized that desflurane would have greater bronchodilating effects because of its ability to increase sympathetic nervous system activity. METHODS: Informed consent was obtained from patients undergoing elective surgery with general anesthesia. We recorded airway flow and pressure after thiopental induction and tracheal intubation (baseline) and for 10 min after beginning volatile anesthesia ( approximately 1 minimum alveolar concentration inspired). Respiratory system resistance was determined using the isovolume technique. RESULTS: Fifty subjects were randomized to receive sevoflurane (n = 20), desflurane (n = 20), or thiopental infusion (n = 10, 0.25 mg. kg-1. h-1). There were no differences between groups for age, height, weight, smoking history, and American Society of Anesthesiologists physical class. On average, sevoflurane reduced respiratory resistance 15% below baseline, whereas both desflurane (+5%) and thiopental (+10%) did not decrease respiratory resistance. The respiratory resistance changes did not differ in patients with and without a history of smoking during sevoflurane or thiopental. In contrast, administration of desflurane to smokers resulted in the greatest increase in respiratory resistance. CONCLUSIONS: Sevoflurane causes moderate bronchodilation that is not observed with desflurane or sodium thiopental. The bronchoconstriction produced by desflurane was primarily noted in patients who currently smoked. (Key words: Bronchospasm; respiratory resistance; volatile anesthetics.)     

NSAID-analgesia, pain control and morbidity in cardiothoracic surgery

OBJECTIVE: While narcotics remain the backbone of perioperative analgesia, the adjunctive role of other analgesics, including non-steroidal anti-inflammatory drugs (NSAIDs), is being recognized increasingly. This meta-analysis sought to determine whether adjunctive NSAIDs improve postoperative analgesia and reduce cumulative narcotic requirements. METHODS: A comprehensive search was undertaken to identify all randomized trials, in cardiothoracic patients, of NSAIDs plus narcotics vs narcotics without NSAIDs. Medline, Cochrane Library, EMBASE, and abstract databases were searched up to September 2005. The primary outcome was visual analogue scale (VAS) pain score. Secondary outcomes included 24-hr cumulative morphine-equivalents, rescue medications required, mortality, myocardial infarction, atrial fibrillation, stroke, renal failure, hospital readmissions, and in-hospital costs. RESULTS: Twenty randomized trials involving 1,065 patients were included. A significant reduction in 24-hr VAS pain score was found in patients receiving NSAIDs [weighted mean difference (WMD) -0.91 points, 95% confidence interval (CI) -1.48 to -0.34 points]. In addition, patients required significantly less morphine-equivalents in the first 24 hr (WMD -7.67 mg, 95% CI -8.97 to -6.38 mg). No significant difference was found with respect to mortality [odds ratio (OR) 0.19, 95% CI 0.01 to 4.22], myocardial infarction (OR 0.71, 95% CI 0.09 to 5.71), renal dysfunction (OR 0.95, 95% CI 0.37 to 2.46), or gastrointestinal bleeding (OR 0.96, 95% CI 0.13 to 7.09). CONCLUSION: In patients less than 70 yr of age undergoing cardiothoracic surgery, the adjunctive use of NSAIDs with narcotic analgesia reduces 24-hr VAS pain score and narcotic requirements.     

What is the best pre‐operative risk stratification tool for major adverse cardiac events following elective vascular surgery? A prospective observational cohort study evaluating pre‐operative myocardial ischaemia monitoring and biomarker analysis

Although brain natriuretic peptide has been shown to be superior to the revised cardiac risk index for risk stratification of vascular surgical patients, it remains unknown whether it is superior to alternative dynamic risk predictors, such as other pre-operative biomarkers (C-reactive protein and troponins) or myocardial ischaemia monitoring. The aim of this prospective observational study was to determine the relative clinical utility of these risk predictors for the prediction of postoperative cardiac events in elective vascular surgical patients. Only pre-operative troponin elevation (OR 56.8, 95% CI 6.5-496.0, p < 0.001) and brain natriuretic peptide above the optimal discriminatory point (OR 6.0, 95% CI 2.7-12.9, p < 0.001) were independently associated with cardiac events. Both brain natriuretic peptide and troponin risk stratification significantly improved overall net reclassification (74.6% (95% CI 51.6%-97.5%) and 38.5% (95% CI 22.4-54.6%, respectively)); however, troponin stratification decreased the correct classification of patients with cardiac complications (-59%, p < 0.001). Pre-operative brain natriuretic peptide evaluation was the only clinically useful predictor of postoperative cardiac complications.