Atenolol premedication in patients undergoing closed mitral commissurotomy

Perioperative tachycardia is common in patients undergoing surgery. In patients with mitral valve stenosis, the tachycardia can precipitate congestive heart failure and pulmonary oedema. Efficacy of atenolol premedication (0.5 mg/kg) for haemodynamic stability was assessed in 37 patients undergoing closed mitral commissurotomy (Group I) and compared with 43 patients who did not receive it (Group II). Patients with mild aortic regurgitation, atrial fibrillation, mild to moderate pulmonary artery hypertension or severe pulmonary artery hypertension without right ventricular failure were all included in the study. All patients were premedicated with tablet diazepam 0.1 mg/Kg, on the previous night and on the day of surgery and intramuscular morphine 0.1 mg/kg and glycopyrrolate 0.2 mg 45 min before surgery. In addition, in group I, atenolol 0.5 mg / kg was administered at night and 2 hours prior to surgery. Anaesthesia was induced with thiopental, morphine, oxygen and isoflurane. Tracheal intubation was facilitated by pancuronium bromide 0.12 mg/kg. Maintenance was with morphine, isoflurane and nitrous oxide in oxygen. The study was confined to the periods of maximal anaesthetic and surgical haemodynamic stress like laryngoscopy, intubation, surgical incision and commissurotomy. For all periods of haemodynamic stress, heart rate was significantly lower in group I, (p<0.05) than Group II. Blood pressure variations were comparable in both the groups. A statistically significant (p<0.001) decrease in systolic, diastolic, and mean arterial pressures, were observed in patients of both groups before and during valvotomy. One patient in atenolol group experienced bradycardia of <45 beats per minute. This was not associated with hypotension and it was easily treated with atropine. This study documents that, selective ss - blockade with atenolol in patients undergoing closed mitral commissurotomy, ensure a predictable control of heart rate in the perioperative period.     

Comparison of the Effects of Sevoflurane and Halothane on Arterial Oxygenation during One Lung Ventilation

We investigated the effect of halothane and sevoflurane on oxygenation during one lung ventilation (OLV) in 24 patients undergoing elective thoracic procedures. After induction with thiopentone, 4-5 mg/kg and morphine 0.1 mg/kg, suxamethonium 2mg/kg was administered to facilitate tracheal intubation with a double lumen tube. Anaesthesia was maintained with 1.5-3% sevolurane (group 1, n = 12) or 1.1.5% halothane (group 2, n = 12) in 02 with N20 (1:1) and pancuronium bromide. Arterial blood gases were recorded before surgery in the lateral position with two lung ventilation (2LV), 10, 20 and 30 minutes after beginning of one lung ventilation. Morphine and endtidal inhalational anaesthetic concentration were titrated to desired anaesthetic depth and haemodynamic variables. Systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR) and central venous pressure (CVP) were measured during the study period. In both the groups there was a significant decrease of PaO2 apparent at 10 minutes after initiation of OLV. Thereafter PaO2 remained stable throughout the study period in both the groups. It is concluded that oxygenation did not differ significantly with either sevoflurane or halothane during OLV. It is also concluded that decrease in oxygenation with OLV is complete by 10 minutes of its initiation.     

先天性心脏病手术两种麻醉药物的比较

目的:通过观察心内直视手术中,舒芬太尼或瑞芬太尼复合七氟烷快通道麻醉对婴幼儿血流动力学,及对术后拔管时间,术后躁动情况和ICU逗留时间的影响。方法: 2011年2月~2012年3月择期行单纯房间隔缺损或室间隔缺损修补术患儿132（男70,女62）例,年龄8个月～5岁,术前NYHA心功能Ⅰ～Ⅱ级。随机分为两组,舒芬太尼组（n=66）和瑞芬太尼组（n=66）。两组均用咪唑安定和维库溴铵诱导麻醉, 舒芬太尼组诱导用舒芬太尼1 μg/kg,术中维持持续泵入舒芬太尼2～2.5 μg/（kg·h）;瑞芬太尼组诱导用瑞芬太尼2 μg/kg,术中维持持续泵入瑞芬太尼0.1～1 μg/（kg·min）维持麻醉,两组均吸入七氟烷,持续泵入维库溴铵80～120 μg/（kg·h）。观察两组患者术前、术中、术后血流动力学变化,分别记录患儿闭眼入睡(基础,T0)、气管插管后(T1)、切皮(T2)、劈胸骨(T3)、开始转机(T4)、转机10 min(T5)、复温5 min(T6)、停机即刻(T7)、停机10 min(T8)、穿钢丝(T9)、手术结束(T10)和拔除气管插管时(T11)的心率（HR）、血压、脑电双频指数（BIS）及术后清醒时间、拔管时间、术后躁动情况和ICU逗留时间的影响。手术结束至拔除气管插管间时间为拔管时间。结果: 与T0 比较,两组患者T8、T9、 T10、T11 HR明显增快（P<0.05）,T1、T5、T6、T8平均血压（MAP）下降（P<0.05））;苏醒情况:舒芬太尼组清醒时间、拔管时间较瑞芬太尼组长（P<0.01）,瑞芬太尼组躁动发生率较舒芬太尼组高（P<0.05）。结论: 舒芬太尼或瑞芬尼复合七氟烷静吸复合麻醉用于婴幼儿单纯ASD或VSD等心内直视手术具有血流动力学稳定,能有效抑制应激反应,术后能早期拔管等特点,均能为婴幼儿先天性心脏病手术提供安全、快捷的快通道麻醉。     

七氟醚与异丙酚麻醉对先心病患儿心肌氧化应激的影响

目的:探讨七氟醚对未成熟心肌保护及清除氧自由基（OFRS）作用。方法: 择期行先天性心脏病患儿手术60例,年龄2~9岁,ASA II或III级, 随机分为七氟醚组(30例),和异丙酚组(30例),麻醉诱导时,七氟醚组吸入氧5~6 L/min+40~60 ml/L七氟醚,异丙酚组异丙酚1~2 mg/kg。两组均采用咪达唑仑0.05~0.1 mg/kg,维库溴铵0.1 mg/kg,舒芬太尼1 μg/kg诱导。麻醉维持七氟醚组吸入4 ml/L~8 ml/L的七氟醚,异丙酚组异丙酚1~3 mg/(kg·h)。两组麻醉维持用维库溴铵0.1 mg/kg,每小时追加1次,舒芬太尼30 μg~40 μg/kg。分别于麻醉诱导前（T0）、体外循环开始前（T1）、体外循环开始后（T2）,手术结束即刻（T3）,从桡动脉抽取桡动脉血2 ml,取血浆测定丙二醛(MDA)含量及超氧化物歧化酶(SOD)的活性。结果: 与异丙酚组比较MDA及SOD,T0、T1无显著变化,T2和T3时七氟醚组SOD显著升高（P<0.05）MDA显著降低（P<0.05）。结论: 七氟醚对未成熟心肌保护作用优于异丙酚,其机制与清除OFRS减少氧化应激等有关。     

Comparison of intubating conditions and haemodynamic effects of rocuronium with vecuronium in patients with poor left ventricular ejection fraction undergoing coronary artery bypass graft surgery

To compare the haemodynamic effects and intubating conditions of rocuronium and vecuronium, 20 patients of either sex with poor left ventricular function (ejection fraction <35%) scheduled for coronary artery bypass surgery were randomly divided into two equal groups. All patients were premedicated with lorazepam and morphine and induced with morphine, midazolam, thiopentone and either vecuronium (0.1 mg/kg) or rocuronium (0.6 mg/kg) as muscle relaxant. All patients were intubated after 3 minutes in the vecuronium group and 90 seconds in the rocuronium group by the same anaesthesiologist. Monitoring in all cases included neuromuscular (train of four- TOF), systemic and pulmonary arterial pressures, cardiac output and calculated haemodynamic variables. Demographic (age, sex and mean ejection fraction) and haemodynamic variables were comparable in both the groups. A significant suppression of the TOF in the vecuronium group was observed despite better intubating conditions in the rocuronium group. The heart rate at 3 minutes and mean arterial pressure at 1 minute was higher in the vecuronium group as compared to the rocuronium group. There were no other significant haemodynamic differences in both the groups. We conclude that rocuronium does provide better intubating conditions at 90 seconds than vecuronium at 3 minutes with no significant differences in the haemodynamic parameters between the two; however, the train of four response does not correlate with intubating conditions.     

右美托咪定对小儿先天性心脏病外科手术麻醉血流动力学的影响

目的探讨右美托咪定对小儿先天性心脏病外科手术麻醉过程中血流动力学的影响。方法将68例在体外循环下行心脏手术的先天性心脏病患儿按随机数字法随机分为咪达唑仑组(n=34)和右美托咪定组(n=34)。麻醉诱导:两组均给予咪达唑仑0.2 mg/kg、芬太尼10μg/kg、维库溴铵0.2 mg/kg行麻醉诱导。麻醉诱导后,行气管内插管,机械通气。麻醉维持:咪达唑仑组输注咪达唑仑0.2 mg.kg-1.h-1和芬太尼10μg.kg-1.h-1,1 h后分别以0.1μg.kg-1.h-1和5μg.kg-1.h-1维持;右美托咪定组输注右美托咪定1μg.kg-1.h-1和芬太尼10μg.kg-1.h-1,1 h后分别以0.5μg.kg-1.h-1和5μg.kg-1.h-1维持。必要时以0.4%～1.0%异氟醚吸入维持麻醉。监测并记录记录麻醉诱导前、麻醉后1 h、切皮前、切皮后即刻、手术结束即刻、手术结束后10 min的血压和心率。结果两组患儿在输注麻醉药物1 h后,收缩压和心率均显著降低,差异有统计学意义(均P<0.05);在切皮时,咪达唑仑组收缩压、舒张压和心率较切皮前明显增高,且明显高于右美托咪定组,差异有统计学意义(均P<0.05);右美托咪定组较少患儿需加用异氟醚,与咪达唑仑组比较,差异有统计学意义[35.3%(12/34)vs.85.3%(29/34),χ2=17.752,P=0.000]。结论与咪达唑仑比较,右美托咪定可更有效的维持小儿先天性心脏病外科手术麻醉过程中的血流动力学稳定。     

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.     

Comparison of sevoflurane and isoflurane in OPCAB surgery

Maintenance of anaesthesia with volatile anaesthetic agents affects the perioperative course of patients undergoing off-pump coronary artery bypass (OPCAB) surgery. This facilitates adequate depth of anaesthesia, reduction in need of analgesic dosage, early extubation and transfer from Intensive Care Unit. We compared two volatile anaesthetic agents sevoflurane and isoflurane in terms of haemodynamic effects, amount of analgesic needed during surgery, quantity of agent needed for maintenance of anaesthesia and postoperative recovery in 40 patients undergoing OPCAB surgery. Anaesthesia was induced with fentanyl, midazolam and thiopentone, and vecuronium was used for muscle relaxation. An Octopus stabiliser was used and coronary anastomosis was performed using internal mammary artery and saphenous vein grafts. Routine monitoring was performed. The depth of anaesthesia was monitored using Bispectral index monitor. The inspired/expired concentration of anaesthetic agents to maintain the desired BIS and the amount of volatile anaesthetic agent needed was also noted. The amount of analgesic used intraoperatively was noted in both the groups. The 'time of awakening' defined as eye opening on verbal commands, and time of extubation were noted. There were no differences in haemodynamic parameters, depth of anaesthesia, and quantity of agent needed, but patients in isoflurane group required more intraoperative analgesics than sevoflurane group. Time of awakening (48+/-13 vs 114 +/- 21 mins; P < 0.001) and subsequent extubation (124 +/- 25 vs 177 +/- 36 mins, P<0.001) was earlier in sevoflurane group than isoflurane group. There was no evidence of perioperative myocardial infarction in both the groups. We conclude that sevoflurane and isoflurane can both be safely used in OPCAB surgery, but the awakening and extubation times are significantly less with sevoflurane.     

Comparison of the effects of desflurane and sevoflurane on the QTc interval and QT dispersion

OBJECTIVE: The effects of desflurane and sevoflurane on QT interval and QT dispersion have been investigated in a prospective, double-blind, randomized study of patients undergoing noncardiac surgery. INTERVENTIONS: Sixty American Society of Anaesthesiologists physical status I-II adult patients were randomly assigned to two groups. Anaesthesia was induced with inhalation of desflurane (desflurane group) or sevoflurane (sevoflurane group) in increasing concentrations to 3 minimal alveolar concentration level. The maintenance of anaesthesia was provided with 2 minimal alveolar concentration agents in both groups until the end of the study. Electrocardiogram, heart rate and blood pressure were recorded as follows: before premedication, before induction, 1 and 3 min after the induction of anaesthesia, after the administration of vecuronium and after the tracheal intubation. The induction times and the complications were recorded. MEASUREMENTS AND RESULTS: The QTc interval was significantly more prolonged with desflurane than with sevoflurane at the first and third minute after the induction, and at the third minute after the administration of vecuronium. There were no significant differences in the QT dispersion between the two groups. Heart rate and blood pressure were found to be significantly higher in the desflurane group. CONCLUSION: The QTc interval was more prolonged with desflurane than sevoflurane, and QT dispersion was normal with both agents.     

不同肌肉松弛药对于先心病患者麻醉诱导时血压和心率的影响

目的 :研究不同肌肉松弛药用于先心病患者麻醉诱导时对血压和心率的影响。方法 :48例择期先天性心脏病矫形手术患者 ,心功能 ～ 级 ,随机分为 6组 ,每组 8例。泮库溴铵、阿曲库铵和维库溴铵 （剂量均为 0 .1mg/ kg）分别合用安定 （0 .2 m g/ kg）和小剂量芬太尼 （5 μg/ kg）或大剂量芬太尼 （10 μg/ kg）。记录插管前、后的血压、心率变化。结果 :与小剂量芬太尼合用进行麻醉诱导时 ,泮库溴铵有增快心率作用 （P<0 .0 1） ,对血压影响不明显 ,阿曲库铵有明显减慢心率作用和降压作用 （P<0 .0 5或 P<0 .0 1） ,维库溴铵有轻度减慢心率作用 （P<0 .0 1） ,对血压影响不大 ;与大剂量芬太尼合用时 ,泮库溴铵对心率的影响不显著 ,并引起血压轻度下降 （P<0 .0 5 ） ,阿曲库铵仍表现明显有减慢心率作用 （P<0 .0 5 ） ,其降压作用的时间有所延长 （P<0 .0 5或 P<0 .0 1） ,维库溴铵减慢心率作用时间有所延长 （P<0 .0 1） ,并使血压显著下降 （P<0 .0 5或 P<0 .0 1）。结论 :先心病矫治术麻醉诱导时宜选择泮库溴铵和较小剂量芬太尼 （5μg/ kg）合用 ,可减少诱导时心动过缓的发生率。     

地佐辛复合芬太尼用于老年心脏病患者非心脏手术后镇痛效果的观察

目的:观察地佐辛复合芬太尼用于老年心脏病患者非心脏手术后镇痛效果及不良反应。方法:60例美国麻醉学家协会(ASA)II或III级择期行全麻手术合并高血压及缺血性心脏病老年患者,随机分为两组:芬太尼组(F组),芬太尼16μg/kg+盐酸托烷司琼10 mg+0.9%氯化钠液至总量100mL;芬太尼复合地佐辛组(FD组),芬太尼8μg/kg+地佐辛0.4 mg/kg+盐酸托烷司琼10 mg+0.9%氯化钠液至总量100 mL。两组患者镇痛液负荷量为5 mL,经静脉注射自控镇痛(PCIA)镇痛泵维持量2mL/h,追加量0.5 mL,锁定时间15 min。记录术后4 h、8 h、12 h、24 h、36 h及48h的视觉模拟评分(VAS)及Ramsay镇静评分、生命体征、术后各时段镇痛效果与镇痛泵按压次数及不良反应。结果:F组与FD组术后各时点VAS评分均<3分,两组间差异无统计学意义(P>0.05);F组术后8 h、12 h及24 h的Ramsay镇静评分明显高于FD组(P<0.05);镇痛期间不良反应发生率FD组低于F组(P<0.05)。结论:地佐辛复合芬太尼用于老年心脏病患者非心脏手术后镇痛治疗,其镇痛效果良好,不良反应发生率低。     

Middle cerebral arterial blood flow velocity and hemodynamics in heart surgery

The aim of this study was to evaluate the effects of propofol, isoflurane, and sevoflurane on middle cerebral arterial blood flow velocity during open heart surgery, and the relationship between these effects and hemodynamic parameters. Fifty-two patients undergoing coronary artery bypass on cardiopulmonary bypass were divided randomly into 3 groups: the first group received 100 microg x kg(-1) x min(-1) propofol, the other groups received one minimum alveolar concentration of sevoflurane or isoflurane for anesthesia maintenance. Middle cerebral arterial blood flow velocities were measured by transcranial Doppler, and hemodynamics were measured by the thermodilution technique. Middle cerebral arterial blood flow velocities decreased significantly after administration of isoflurane and propofol, but there was no significant difference between the groups. After weaning from cardiopulmonary bypass, cerebral blood flow increased and came close to the value after induction in all groups. The pulsatility index and resistivity index increased significantly only after the propofol infusion, but there was no significant difference between the groups.     

Effect of muscle relaxants on heart rate, arterial pressure, intubation conditions and onset of neuromuscular block in patients undergoing valve surgery

Sixty six patients undergoing elective valve surgery were randomized to receive rocuronium bromide 0.6 mg/Kg (Group R, n=22), pancuronium bromide 0.1 mg/Kg (Group P, n= 22) and vecuronium bromide 0.1 mg/Kg (Group V, n=22), Measurements of heart rate and arterial pressure (systolic, diastolic and mean) were noted at the following stages: 1) baseline when haemodynamics were stable for 2 minutes after induction of anaesthesia (2) one, (3) three, (4) five minutes after administration of muscle relaxants, (5) One, (6) three, and (7) five minutes after intubation. In group R, the heart rate decreased 5 min after injection of muscle relaxant from 93.9 +/- 21.3 to 82.4 +/- 20.7 beats/min (p<0.001). However, it increased to 128.3 +/- 25.8 beats/min (p<0.001) following intubation and returned to baseline at 5 min after intubation. In group P, heart rate increased from 98.8 +/- 32.6 to 109.6 +/- 32.7 beats/min (p<0.001), 1 min after injection of pancuronium and this increase persisted throughout the study period. In group V, heart rate decreased from 99.9 +/- 22.3 to 83.8 +/-19.6 beats/min (p<0.001) at 5 min after injection of the drug. It increased to 118.6 +/- 22.4 beats/min (p<0.001), 1 min after intubation and returned to baseline at 5 min after intubation. The decrease in heart rate in group R and V was accompanied by a significant decrease in systolic, diastolic and mean arterial pressure. In group P, only the systolic pressure decreased significantly at 5 min after injection of the drug. Intubation was accompanied by a significant increased in systolic, diastolic and mean arterial pressure in all the groups. Excellent intubation conditions (intubation score 3-4) were observed with all the three drugs, however, there were number of patients in group P who showed diaphragmatic movement during intubation. Onset of action of muscle relaxant, was fastest with rocuronium (group R=132.7 +/- 0.3 sec, P=182.6 +/- 68.5 sec, V= 144.8 +/- 46.1 sec, Group P vs Group R). To conclude, pancuronium causes significant increase in heart rate and should be preferred in patients with regurgitant lesions having slower baseline heart rate. Vecuronium and rocuronium decrease the heart rate and should be preferred in patient with faster baseline heart rate. In terms of intubating conditions rocuronium and vecuronium provide best conditions, but onset is faster with rocuronium.     

Effects of intravenous lidocaine on QTd and HRV changes due to tracheal intubation during sevoflurane induction

The aim of the present study was to evaluate the effects of IV lidocaine on autonomic cardiac function changes in tracheal intubation (TI) during sevoflurane anaesthesia by using more reliable parameters, namely, the analysis of QT dispersion and heart rate variability (HRV) from Holter monitoring. In this prospective, double-blind study, 44 American Society of Anaesthesiologists class I-II patients scheduled for hysterectomy were randomly and equally divided into 2 groups; a control sevoflurane group (group S, n = 22) and a lidocaine sevoflurane group (group LS, n = 22). Before the induction of anaesthesia, the electrocardiograms (ECG) of all patients were recorded for 3 minutes as baseline parameters. In both groups, the anaesthesia was induced with 7% sevoflurane in O(2 )at 6L min(-1) via a facemask for 2 minutes. However, before the induction of sevoflurane anaesthesia in group LS, 1 mg kg(-1) of lidocaine was given intravenously (IV). For muscle relaxation during TI, vecuronium was given to all participants. Three minutes after administration of vecuronium, TI was performed and an ECG was recorded synchronously for another 3 minutes. The results from the later records were used as postintubation parameters. Baseline and postintubation data were analysed. When compared to baseline values, postintubation LF/HF and SDNN values were increased in group S (P = 0.005, P = 0.001, respectively), whereas postintubation LF and HF values were decreased in group LS (P = 0.014, P = 0.041, respectively). Under the influence of sevoflurane anaesthesia, TI resulted in sympathetic activation. However, this activation was attenuated by the administration of IV 1 mg kg(-1) lidocaine 5 minutes prior to TI.     

舒芬太尼与芬太尼对非体外循环冠状动脉旁路移植术患者谵妄发生率的对比研究

目的:对比舒芬太尼与芬太尼麻醉对非体外循环下冠状动脉旁路移植术(OPCABG)患者谵妄发生率的影响。方法:拟行OPCABG的患者48例,年龄60～65岁,随机分为2组(n=24):舒芬太尼组(S组)与芬太尼组(F组)。2组均静脉注射咪达唑仑、依托咪酯、维库溴铵及舒芬太尼1～2μg//kg(S组),芬太尼10～20μg/kg(F组)进行麻醉诱导,气管插管后行机械通气。麻醉维持:S组静脉输注舒芬太尼0.5～1.5μg.kg-1.h-1,F组静脉输注芬太尼5～15μg.kg-1.h-1,2组均吸入0.5%(2.0%异氟烷,间断静脉注射维库溴铵。S组静脉输注舒芬太尼2μg/h,F组输注芬太尼20μg/h进行术后静脉镇痛。分别于术前、术后1d、2d、3d、4 d及5 d进行谵妄分值评估。于术前及术后1d测定血清C-反应蛋白浓度,并于记录血流动力学指标、ICU停留时间和术后并发症的发生情况。结果:与F组比较,S组术后谵妄发生率低(P<0.01),术后1 d C-反应蛋白较F组低(P<0.05),术后发热发生率降低(P<0.01),其他不良反应2组间差异无统计学意义(P>0.05)。结论:舒芬太尼-复合麻醉可降低OPCABG患者术后炎症反应程度,并降低术后谵妄的发生率。     

Influence of β-blockers on vecuronium/sufentanil or pancuronium/sufentanil combinations for rapid induction and intubation of cardiac surgical patients

Use of pancuronium or vecuronium with the priming principle was evaluated in regards to hemodynamic changes and adequacy of relaxation for a rapid induction-endotracheal intubation sequence with sufentanil in 24 ASA Class III-IV patients undergoing cardiac surgery. Twelve patients taking β-blockers (groups B-P and B-V) were compared with 12 patients not receiving β-blockers (groups NB-P and NB-V). Patients randomly received vecuronium or pancuronium (15 μig/kg), followed in 4 minutes by sufentanil 5 μg/kg and another 85 μg/kg of the appropriate relaxant through a central vein. Intubation was possible in all patients at 90 seconds with good-to-excellent conditions. Heart rate (HR) remained statistically elevated after induction (90 ± 10 beats/min) and intubation (105 ± 10 beats/min) only in group NB-P (baseline 74 ± 12 beats/min). The NB-P group also had an elevated blood pressure after the priming dose. No significant hemodynamic changes were found in the other groups in mean arterial pressure, pulmonary artery diastolic pressure, systemic vascular resistance (SVRI), or cardiac index (CI). When used with vecuronium, sufentanil in a dose of 5 μg/kg provided adequate anesthesia to avoid the hypertensive, tachycardic response that frequently occurs following a rapid intravenous (IV) induction, without unduly depressing cardiac output or arterial pressure. Two patients had evidence of respiratory difficulty after the priming dose, associated with transient tachycardia and hypertension which resolved after induction. Using the priming principle, either pancuronium or vecuronium rapidly provided relaxation in patients with cardiac disease. Chronic β-blocker therapy was able to attenuate the tachycardia from pancuronium and was not associated with bradycardia when used with vecuronium. In patients with cardiac disease not on β-blockers, pancuronium was associated with tachycardia. Therefore, vecuronium appears to be more suitable for these patients.     

Effects of single administration of a phosphodiesterase III inhibitor during cardiopulmonary bypass: comparison of milrinone and amrinone.

The effects of phosphodiesterase III (PDE III) inhibitors administered after aortic declamping during cardiopulmonary bypass (CPB) for open heart surgery were investigated. Ten patients (group M) were administered milrinone (50 microg/kg) after aortic declamping during CPB, 10 patients were administered amrinone (1 mg/kg) at the same time during their surgery (group A), and 10 patients served as controls with no drug administered (group C). Soon after bolus infusion of the PDE III inhibitor, perfusion pressure dropped significantly in groups M and A. However, after release of CPB and at the end of surgery, there was no difference in aortic pressure between the 3 groups. There were also no differences between the groups in heart rate, pulmonary artery pressure, and pulmonary capillary wedge pressure. After weaning from CPB, the cardiac index was high and systemic vascular resistance index was low in groups M and A. There were no significant differences in the need for additional catecholamines and time for rewarming between groups. No adverse reactions were observed. A single administration of a PDE III inhibitor during CPB was useful for post-CPB management of patients undergoing open heart surgery. Amrinone reduced perfusion pressures more than milrinone, but cardiac indices and aortic pressures after weaning from CPB showed no differences between group M and group A patients.     

Antihypertensive and anti-ischemic effects of nicardipine and nitroprusside in patients undergoing coronary artery bypass grafting

The efficacy of nicardipine vs nitroprusside in controlling hypertension after sternotomy was compared in 120 patients undergoing coronary artery bypass grafting and anesthetized with fentanyl (100 micrograms/kg). All had good left ventricular function and had been receiving long term oral beta-blocking therapy. Patients were randomly allocated to 1 of 3 groups: group C, the control (n = 40), received no vasodilator; group N (n = 40) received intravenous nicardipine at an initial rate of 3 micrograms/kg/min; and group S (n = 40) received intravenous nitroprusside at an initial rate of 1 microgram/kg/min. Vasodilator infusion was begun before surgery and infusion rates were adjusted to maintain systolic blood pressure between 80 and 120% of postintubation (baseline) values. Additional measurements were obtained before incision and after sternotomy. In groups N and S, arterial blood pressure was effectively controlled in all patients. Before the incision, pulmonary artery pressure decreased in group S and systemic vascular resistance decreased in groups N and S. After sternotomy, mean arterial pressure, heart rate, pulmonary artery pressure, pulmonary capillary wedge pressure, cardiac index and rate-pressure product increased in group C. At this time, pulmonary artery pressure returned to baseline values in group S. In groups N and S, heart rate, cardiac index and rate-pressure product increased, but, compared with baseline values, systemic vascular resistance remained low after sternotomy. Ischemic changes were seen in the electrocardiogram in 11 patients (28%) in group C, 10 patients (25%) in group S and 4 patients (10%) in group N. The concentration of creatine phosphokinase MB was not significantly different in the first 24 postoperative hours in any group.     

Comparison of isollurane with sodium nitroprusside for controlling hypertension during thoracic aortic cross-clamping

The aims of this randomized study were (1) to determine if isoflurane is effective in controlling blood pressure during thoracic aortic cross-clamping, and (2) to compare its effects on hemodynamics and oxygen transport to those of sodium nitroprusside. Sodium nitroprusside (SNP group, n = 10) or isoflurane (ISO group, n = 10) was started 2 minutes before cross-clamping and was adjusted to maintain systolic arterial pressure as near as possible to preinduction values. The duration of thoracic aortic cross-clamping was 26 ± 4 minutes in the SNP group and 30 ± 4 minutes in the ISO group. Administration of isoflurane and sodium nitroprusside was stopped 2 minutes before unclamping. The same anesthetic technique using fentanyl, 6 μg/kg, flunitrazepsm, 0.02 mg/kg, pancuronium, 0.1 mg/kg, and 50% N₂O was used for all patients. At the time of clamping, either isoflurane (maximal expired concentration, 2.6% ± 0.3%) or sodium nitroprusside (cumulative dose, 11.1 ± 1.0 mg) was effective in maintaining the systolic blood pressure below 160 mm Hg, whereas the pulmonary capillary wedge pressure did not change. However, only SNP was able to bring the arterial pressure above the cross-clamp back to postinduction levels. During clamping, stroke index values were similar in both groups, but cardiac index increased only in patients receiving SNP. In both groups, at clamping and unclamping, PvO₂ was higher than postinduction values, indicating that throughout the study the oxygen needs of the perfused area were adequately met. There was no evidence of acute left ventricular decompensation because pulmonary capillary wedge pressures did not abruptly increase, nor did pulmonary edema occur. It is concluded that isoflurane added to fentanyl anesthesia is acceptable for thoracic aortic aneurysm surgery because it allows safe and effective control of hypertension during clamping without compromising hemodynamics and oxygen transport.     

Prebypass hemodynamic stability of sufentanil-O2, fentanyl-O2, and morphine-O2 anesthesia during cardiac surgery: A comparison of cardiovascular profiles

Cardiovascular responses and the need for intervention with vasoactive agents were measured prospectively in a randomized study of 50 adult patients receiving sufentanil (n = 20), fentanyl (n = 20), or morphine (n = 10) anesthesia for cardiac surgery. Measurements were recorded and compared during induction and prebypass at intervals during which airway or surgically induced stress responses were likely to be greatest. Randomized, double-blinded doses of opioids were administered slowly and titrated according to clinical responses (hemodynamics) and the electroencephalogram. Mean doses were as follows: from induction until time of incision, sufentanil, 9.1 μg/kg; fentanyl, 58 μg/kg; and morphine, 2.5 mg/kg; and total dose for surgery; sufentanil, 18.9 μg/kg; fentanyl, 95.4 μ/kg; and morphine, 4.4 mg/kg. Equi-anesthetic depth in patients receiving sufentanil or fentanyl was confirmed by continuous electroencephalographic monitoring. Patients anesthetized with sufentanil and fentanyl showed marked cardiovascular stability and rarely responded to stimuli. Systolic arterial pressure, mean arterial pressure, heart rate, cardiac index, systemic vascular resistance index, pulmonary vascular resistance index, stroke volume index, and stroke work index values were similar in the two groups. Patients receiving morphine experienced large changes in several variables. Pharmacologic intervention was made when systolic arterial pressure deviated more than 30% from pre-event values and was uncontrolled by additional opioids. Interventions were necessary more often in patients receiving morphine (nine of ten) or fentanyl (12 of 20) than in patients receiving sufentanil (six of 20), P < 0.05. Results from this study suggest that morphine is a relatively unsatisfactory anesthetic, while sufentanil and fentanyl, at equi-anesthetic depths, provide stable and satisfactory hemodynamics.