Comparative evaluation of cardiovascular effects of sevoflurane and isoflurane in patients with ischaemic heart disease undergoing non-cardiac surgery

Twenty three adult patients with ischaemic heart disease undergoing elective non-cardiac surgery were studied. Induction of anaesthesia was similar for each patient and included thiopentone (4-5 mg/kg), morphine (0.1 mg/kg) and vecuronium (0.1 mg/kg). Additional morphine and vecuronium were used when necessary. All these patients were maintained with either sevoflurane (n=11) or isoflurane (n=12). The inhaled anaesthetics were titrated to achieve adequate clinical 'depth of anaesthsia' and to maintain mean arterial pressure within 20% of the pre-induction values. Heart rate, blood pressure and rate-pressure product were recorded during the maintenance phase of anaesthsia. ST-T changes were also monitored during this period. There was a tendency for heart rates to be significantly higher shortly after skin incision till the end of procedure in the isoflurane group, while in the sevoflurane group heart rate remained stable during the surgical procedure. Both systolic and diastolic blood pressure remained similar in both groups. The rate pressure product was higher in the isoflurane group than in the sevoflurane group at 30 min Post-incision. The data suggests that sevoflurane is not associated with untoward cardiovascular changes in ischaemic heart disease patients undergoing non-cardiac surgery.     

Comparison of pulmonary gas exchange in OPCAB versus conventional CABG

BACKGROUND: Cardiopulmonary bypass has been implicated as a cause of acute lung injury in cardiac surgical patients. This could be avoided with off-pump coronary artery bypass surgery. Aim. To ascertain the possible benefit of OPCAB surgery on pulmonary gas exchange. METHODS: We randomized 75 consecutive patients (mean age 57 years) into two groups: Group 1 off-pump coronary artery bypass surgery (OPCAB), n=37, Group 2 conventional coronary artery bypass grafting (con CABG), n=38. Alveolar-arterial oxygen difference (A-aO(2) difference) was calculated pre-operatively, then 2 and 4h post-operatively. PaO(2)/FiO(2) ratio and respiratory index (RI) were calculated 2 and 4h post-operatively. RESULTS: Alveolar-arterial O(2) gradient sharply increased in the immediate post-operative period, from 27mmHg pre-operatively, to 227mmHg 2h post-operatively, then declined to 152mmHg 4h post-operatively. PaO(2)/FiO(2) ratio and RI also showed severe worsening 2h post-operatively, with marked improvement at 4h. The pattern of physiological deterioration of gas exchange was similar in both the groups. CONCLUSION: In terms of pulmonary gas exchange, similar degree of deterioration is noticed in CABG patients with or without cardiopulmonary bypass. OPCAB seems to provide no physiological benefit of gas exchange at the alveolar capillary membrane when compared to conventional CABG.     

Comparison of the synergistic effects of sevoflurane and desflurane on muscle relaxant vecuronium in laparoscopic colon cancer surgery

Sevoflurane and desflurane are commonly used inhalation anesthetics in clinical practice. This study compared the synergistic effects of sevoflurane and desflurane on the muscarinic agent vecuronium in laparoscopic colon cancer surgery. The aim of this study was to compare sevoflurane and desflurane in a synergistic effect on the muscle relaxant vecuronium in laparoscopic colon cancer surgery. Sixty patients undergoing elective laparoscopic radical resection of colon cancer were randomly divided into sevoflurane (n = 30) and desflurane (n = 30) groups. After anesthesia and successful tracheal intubation, patients in both groups were maintained with combined remifentanil. Muscle relaxant effects were monitored in both groups using a muscle relaxant monitor (train of stimuli-Watch), the onset time, T1 and T2 recovery time, and muscle relaxant dosage of vecuronium were observed. Hemodynamic changes were observed in both groups, and the dosage of vasoactive drugs was recorded. The quality of recovery of the patients was evaluated using the Mini-Mental State Examination (MMSE) and the discharge from the Aldrete score criteria. There was no significant difference in the onset time of vecuronium between the two groups (P > .05). The desflurane group’s T1 and T2 recovery times were later than that of the sevoflurane group. The dosage of vecuronium was statistically significantly less than that in the sevoflurane group (P < .05); the extubation time in the desflurane group was statistically significantly longer than that in the sevoflurane group (P < .05). There were no significant differences in preoperative and intraoperative mean arterial pressure, heart rate, ephedrine and atropine dosage, MMSE score, and Aldrete score between the 2 groups (P > .05). Compared with sevoflurane, desflurane has a stronger synergistic effect on the muscle relaxant of vecuronium without increasing the incidence of cardiovascular adverse reactions and affecting patient recovery.     

Vettath's blower and blower/mister - a simple device for OPCAB surgery

Since the advent of off-pump coronary artery bypass surgery, a blower/mister has been routinely used in cardiac operation theatres. In our setup, in an attempt to reduce the cost of coronary artery bypass grafting by performing off-pump coronary artery bypass, reusable materials have been routinely used.     

Thyroid function during isoflurane anesthesia and valvular heart surgery

Proper thyroid function is essential for maintaining cardiovascular integrity during normal and stressful situations. In this study, the effects of isoflurane-O₂ anesthesia and surgical stress on serum TSH, T₄, free T₄, T₃, rT₃ and cortisol were investigated in nine patients before, during, and after valve surgery. Compared with preoperative control values, serum TSH decreased in the postoperative period. Both T₄ and free T₄ had similar decreases after cardiopulmonary bypass (CPB) and remained depressed postoperatively. Both T₃ and rT3 decreased at the start of cardiopulmonary bypass; T₃ remained low in the postoperative period, while rT₃ increased. Cortisol decreased during anesthesia and surgery in the prebypass period, but increased during cardiopulmonary bypass and in the postoperative period. The results suggest that isoflurane-O₂ anesthesia during valve surgery produces a rapid decrease in T₃, resulting in the low T₃ syndrome postoperatively. Isoflurane, in the dose studied, similar to fentanyl, can suppress the cortisol response to anesthesia and surgery in the prebypass period, but not during and after CPB.     

Comparison of cardiac output in OPCAB: bolus thermodilution technique versus pulse contour analysis

The study was designed to evaluate the clinical agreement between intermittent bolus thermodilution technique and pulse contour analysis technique. Sixty patients with normal left ventricular function undergoing elective off-pump coronary bypass surgery were included in this prospective study. In addition to routine monitoring, a 7.5F pulmonary artery thermodilution catheter via right internal jugular vein and a 4F arterial thermodilution catheter into femoral artery were also placed. Cardiac output measurements were compared before induction, after induction, after sternotomy, during the various anastomoses, post-protamine and post-sternal closure. Statistical analysis was performed using analysis of agreement to assure bias distribution of differences between the two methods by using Bland and Altman analysis. The cardiac output values obtained at preinduction, post-induction, and post-sternal closure time points showed good agreement, whereas the values obtained during the various anastomoses showed significant differences (p <0.05). Therefore it was concluded that pulse contour analysis cannot be relied upon completely whenever there is a change in the position of heart or alteration in systemic vascular resistance. But the trends in cardiac output were in complete agreement during the entire procedure.     

Comparative study of perioperative infusion of diltiazem and nicorandil on myocardial protection during OPCAB surgery

We compared the effects of continuous intravenous infusions of nicorandil and diltiazem on left ventricular function, haemodynamics and as anti-ischaemic and anti-arrhythmic agents in 50 patients undergoing off pump coronary artery bypass surgery using arterial conduits. The patients were randomized into two equal groups to receive diltiazem or nicorandil. Both the drugs were given as a continuous infusion in the dose of 1microg/kg/min starting at induction and continued for 24 hours postoperatively. Haemodynamic parameters, cardiac enzyme levels and use of vasoactive agents were studied and compared using ANOVA, unpaired "t" and Fisher's exact tests. The two groups did not differ with respect to preoperative and operative data. Diltiazem group showed lower cardiac index (2.66+/-0.8 and 2.27+/-0.89 L/min/m2) as compared with nicorandil group (3.16+/-0.79 and 2.97+/-1.01 L/min/m2) during revascularisation of anterior (P=0.03) and inferior (P=0.01) circulation respectively. The systemic vascular resistance index was higher (2290+/-699 and 2545+/-911 dync.sec.cm-5.m2) in diltiazem group as compared with nicorandil group (1822+/-532 and 1877+/-548 dyne. sec.cm-5.m2) during revascularization of anterior (P=0.01) and inferior (P=0.002) circulation respectively. The mean pulmonary artery pressure was significantly higher in nicorandil group as compared with diltiazem group during revascularisation of anterior circulation (22.5+/-4.9 and 18.1+/-6.8 mmHg, P=0.01). The patients in the diltiazem group maintained a lower heart rate throughout the study period, but the difference was not statistically significant. None of the patients exhibited any arrhythmia except one in nicorandil group, who developed supraventricular arrhythmia 24 hours postoperatively. Cardiac enzyme levels were found to be similar in the two groups. The present study demonstrates that the anti-ischemic and antiarrythmic effects of diltiazem and nicorandil are comparable, but diltiazem causes a decrease in cardiac index and increase in systemic vascular resistance index during revascularization of anterior and inferior circulation.     

Comparison of the hemodynamic and echocardiographic effects of sufentanil,fentanyl, isoflurane,and halothane for pediatric cardiovascular surgery

Sufentanil, fentanyl, halothane, and isoflurane were compared as sole anesthetic agents in 48 infants and children aged 6 months to 9 years, undergoing repair of congenital heart defects. Patients were randomly assigned to receive sufentanil, 20 μg/kg, fentanyl, 100 μg/kg, isoflurane, 1.6%, or halothane, 0.9%, along with pancuronium, 0.08 mg/kg, for induction and maintenance of anesthesia. Cardiovascular function was measured by echocardiography prior to induction, postinduction, and postintubation. Systemic arterial pressure and heart rate were also recorded. Left ventricular ejection fraction (LVEF) decreased following induction with each agent: sufentanil 9%, fentanyl 9%, isoflurane 4%, and halothane 8%. Following intubation LVEF increased in the sufentanil, fentanyl, and isoflurane groups, but LVEF remained 13% below baseline values in the halothane group. Five of the 12 patients in the halothane group had a LVEF less than 55%. Arterial pressure immediately prior to bypass was significantly less than baseline in each group; however, arterial pressure was higher in the narcotic groups during isolation and cannulation of the great vessels. It is concluded that halothans, 0.9%, used as an induction agent in infants and children undergoing cardiac surgery causes a clinically significant decrease in LVEF. Based on the echocardiographic data, sufentanil, fentanyl, and isoflurane as used in the present study do not have a clinically significant effect on cardiac function and may offer an advantage to infants and children with marginal cardiovascular reserve.     

Patterns and diagnostic value of cardiac troponin I vs. troponin T and CKMB after OPCAB surgery.

BACKGROUND: Cardiac troponin I (cTnI) has been shown to be a specific marker for myocardial injury in cardiac surgery. The object of this prospective study was to determine the patterns and kinetic and diagnostic value of cTnI, cardiac troponin T (cTnT), and creatine kinase MB (CKMB) activity after minimally invasive coronary revascularization using an octopus device on the beating heart (OPCAB). METHODS: 48 patients (33 male/15 female, mean age 68.3 +/- 8.7 years) underwent their first elective OPCAB surgery with median sternotomy without mortality. The mean number of grafts was 2.0 +/- 0.8 per patient. Preoperative mean ejection fraction was 56.6 % +/- 14.9%. CTnI and T levels, total creatine kinase (CK) and CK-MB activity in the serum were measured before operation, at arrival at the ICU, and 6, 12, 24, 48 and 120 hours afterward. Serial 12-lead ECGs were recorded preoperatively and at days 1, 2 and 5. The relationship between perioperative data and postoperative cTnI and cTnT levels and CKMB were statistically identified for all variables. RESULTS: The best cutoff value for cTnI was 8.35 micrograms/l. The patients were grouped by the ECG findings and maximal slopes of cTnI postoperatively (group I: unchanged ECG and cTnI < 8.35 micrograms/l, n = 38; group II: unchanged ECG and cTnI > 8.35 micrograms/l n = 6; group III: Q-wave in ECG and cTnI > 8.35 micrograms/l, n = 4). Baseline serum concentrations of cTnI were in the normal range, and significantly increased after surgery with a peak 24h after the operation. Maximal slopes of cTnI ranged in group II between 9.1 and 18.0 micrograms/l, and in group III between 35.9 and 88.8 micrograms/l. There was strong concordance between maximum cTnI, cTnT (p < 0.0001) and CK-MB levels (p = 0.003). First cTnI levels immediately post-op correlated with the maximum cTnI levels during the postoperative course (p = 0.009). CONCLUSIONS: CTnI after minimal invasive surgery shows a characteristic pattern with a maximum at 24h after the operation. The measurement of postoperative biochemical marker concentrations, specially cTnI, reflects myocardial injury incurred during the procedure. It is an accurate method for confirming or excluding a perioperative myocardial injury diagnosis after OPCAB surgery.     

七氟醚预处理在小儿心脏手术中的心肌保护作用

目的 观察七氟醚对小儿心脏手术围术期炎症反应的影响及其心肌保护的效果.方法 选择24例择期行先天性心脏病手术的患儿,随机分成实验组(S组)和对照组(C组),每组12例.S组在麻醉诱导气管插管后至夹闭主动脉前吸入七氟醚(呼气末浓度为2%),而C组只吸入纯氧.分别于麻醉诱导前即刻(T0)、主动脉开放后20 min(T1)、停CPB 4 h(T2)、24 h(T3)采集桡动脉血,测定肿瘤坏死因子α(TNF-α)、血浆心肌肌钙蛋白I(cTnI)水平.结果 与T0时比较,两组T1～3时TNF-α和cTnI水平均升高(P <0.05);与C组比较,S组T1-3时TNF-α浓度降低,T2～3时cTnI水平降低(P <0.05).cTnI与TNF-α呈正相关,相关系数r为0.67.结论 七氟醚预处理通过抑制炎症反应,对小儿CPB患者心肌产生一定的保护作用.     

老年病人术中脑电双频指数与七氟烷浓度关系的研究

目的 研究老年病人静吸复合麻醉时,七氟烷浓度与脑电双频指数(BIS)及年龄之间的关系.方法将普外科上腹部手术病人30例(ASA分级Ⅱ～Ⅲ),按年龄分为两组:A组为60～69岁;B组为70～79岁,每组15例.采用七氟烷与瑞芬太尼静吸复合麻醉,调节七氟烷浓度使BIS值在50～60.记录术中各时间段吸气末和呼气末七氟烷浓度及BIS值,并记录睁眼时间(从停止吸入麻醉药至病人睁眼时间)、拔管时间、麻醉恢复时间(从停止吸入麻醉药至恢复定向力的时间),对两组病人的年龄与呼气末七氟烷浓度及BIS值之间进行回归分析.结果两组病人各项生命体征平稳,年龄与呼气末七氟烷浓度具有显著的相关性.两组病人两个时间点(手术开始30 min与60 min)的呼气末七氟烷浓度与BIS值之间的相关系数均>0.60,大部分具有显著相关性.两组患者睁眼时间、拔管时间、麻醉恢复时间差异无统计学意义,两组患者术后随访均无术中知晓.结论老年病人年龄与七氟烷浓度及BIS值之间具有显著的相关性,临床麻醉中要根据病人的年龄选择合适的七氟烷浓度,同时BIS值可以作为调节七氟烷麻醉深度的一个重要参考指标.     

心外膜超声结合TTFM在OPCAB术中的应用

目的：分析评估心外膜超声结合即时血流测量仪(TTFM)在非体外循环冠状动脉搭桥(OPCAB)术中的应用效果及体会。方法：回顾分析2016年1月-2016年12月共有85例行非体外循环冠状动脉搭桥术的病人术中应用了心外膜超声及TTFM,其中男46例,女39例,年龄44-82岁,平均年龄65.6岁。搭桥采用全动脉化方案(左侧乳内动脉 双侧桡动脉)9例,全静脉化方案(Y型桥)2例,其余均为左侧乳内动脉 大隐静脉常规方案,静脉桥均采用先吻合主动脉近端的方式,且均为序贯桥;术后1、3、6月进行随访。结果：1例左乳内动脉与前降支吻合后,检测桥血管发现流量低及血流阻力高,遂拆除原吻合口重新做桥血管吻合,再次检测流量及血流阻力满意。其余手术均顺利完成,术毕测桥血管流量及血流阻力均达到临床标准;术中血流动力学稳定,无围术期急性心梗及死亡病例,术后无脑血管事件发生,无主动脉损伤等主动脉不良事件,术后短期随访期间无心绞痛复发病例。结论：冠状动脉搭桥术中应用心外膜超声,可以有效避开粥样斑块,将吻合口做在内膜相对光滑的靶血管上,有利于保证吻合口的近、远期通畅;术毕应用TTFM,可以即时检测桥血管流量及血流阻力,保证了手术的安全性,值得在临床上广泛推广应用。     

Influences of tramadol on emergence characteristics from sevoflurane anesthesia in pediatric ambulatory surgery

Sevoflurane is used for pediatric ambulatory surgery due to its low blood solubility, rapid emergence, non-pungency and low airway irritability. Nevertheless, its tendency to induce agitation during emergence may offset its benefits. The following study was designed to evaluate the effects of intravenous (i.v.) tramadol (1 mg/kg) on the emergence from sevoflurane anesthesia. Forty ASA I children, ranging from 1 to 8 years old, scheduled for inguinal surgery, were randomized into two groups (Group S--control group, Group ST--i.v. tramadol, 20 in each group). The patients were first premedicated with oral atropine (0.01 mg/kg), then anesthesia was induced with i.v. application of thiamylal (3-4 mg/kg) and maintained with mask anesthesia with sevoflurane. Topical infiltration with 2-3 ml of 1% lidocaine was applied over skin incision area. I.v. tramadol (1 mg/kg) was given before the end of operation in Group ST. The emergence agitation was recorded on a visual analog scale (VAS, 0-10) by a blinded anesthesiologist in the PACU (postoperative anesthesia care unit), as well as the length of other recovery stages and complications after anesthesia. The age, weight, gender, and duration of surgery and anesthesia were similar in the two groups. The emergence agitation score (6.3 +/- 3.5 vs. 3.2 +/- 2.8, P < 0.05), incidences of agitation (VAS > 5, 55% vs 20%, P < 0.05), and postoperative pain (65% vs 30%, P < 0.05) were higher for the control group. I.v. Tramadol (1 mg/kg) before the end of operation reduced postoperative pain and the incidence and degree of emergence agitation from sevoflurane anesthesia in pediatric ambulatory surgery.     

非体外循环冠状动脉旁路移植术中肝素诱导血小板减少并血栓形成一例

1病例资料 患者女性,59岁,因“阵发性心前区闷痛6年,加重1年”,于2012年3月9日入院。既往有高血压、糖尿病病史,一直口服药物治疗,血压、血糖控制可。入院前曾皮下使用肝素抗凝治疗。入院查体：血压140／70mmHg（1mmHg=0．133kPa）,心肺查体未见明显异常。实验室检查,血常规：