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.     

A randomized double-blind comparison of fentanyl- and sufentanil-oxygen anesthesia for abdominal aortic surgery

Twenty-four patients undergoing abdominal aortic surgery for aneurysm or occlusive vascular disease entered a randomized, double-blind protocol comparing high-dose narcotic anesthesia with fentanyl (125 μg/kg) or sufentanil (25 μg/kg). All patients received perioperative β-adrenergic blockade therapy. Hemodynamic and electrocardiographic (leads 11 and V₅) responses to induction, intubation, skin incision, aortic cross-clamping, and declamping were studied. Sufentanil produced a transient decrease in mean arterial pressure and a significant reduction of systemic vascular resistance during induction. However, no significant hemodynamic differences were observed between the two groups during intubation, or at any other time during surgery. To maintain mean arterial pressure within 20% of the awake control value, the fentanyl group required an average infusion of 1.0 ± 1.1 μg/kg/min of nitroglycerin compared with 1.7 ± 2.8 μg/kg/min for the sufentanil group. Low-dose isoflurane was required in 30% of patients in the fentanyl group, compared with 41 % of the sufentanil group, for control of blood pressure. The multiple-bolus technique of narcotic administration resulted in a wide but parallel range of plasma concentrations from induction to the end of surgery with both narcotics. Mean plasma fentanyl concentrations varied between 7.2 ± 1.4 ng/mL and 26.5 ± 7.9 ng/mL, and mean sufentanil plasma concentrations varied between 1.0 ± 0.1 ng/mL and 10.6 ± 7.2 ng/mL throughout surgery. Within this range of narcotic serum levels, the authors were unable to identify a specific threshold level for either narcotic above which hemodynamic responses were consistently attenuated. A low incidence (4.5%) of intraoperative myocardial ischemia was observed. It is concluded that sufentanil and fentanyl are not different at blunting hemodynamic responses during aortic surgery. When supplemented by low doses of nitroglycerin and isoflurane, both narcotics provide anesthesia characterized by good hemodynamic control and a low incidence of myocardial ischemia.     

Hemodynamic effects of a lorazepam-fentanyl anesthetic induction for coronary artery bypass surgery

Previous anesthetic induction techniques using the combination of a benzodiazepine (midazolam or diazepam) and fentanyl have been reported to produce marked hypotension. In this study, anesthesia was induced with a combination of lorazepam and fentanylin in patients undergoing coronary artery bypass graft surgery. In 10 patients, anesthesia was induced using an exponentially declining continuous infusion of lorazepam equivalent to a total infused dose of 0.1 mg/kg over 15 minutes, which was supplemented at 10 minutes by fentanyl, 75 μg/kg, given as an infusion over 5 minutes. In 8 additional patients, anesthesia was induced with an exponentially declining infusion of fentanyl to a total dose of 75 μg/kg over 15 minutes, which was supplemented at 10 minutes by lorazepam, 0.1 mg/kg, given as an infusion over 5 minutes. Hemodynamics were recorded during a 20-minute observation period. One patient in each group required treatment for bradycardia during the initial drug infusion (before the second drug was added). Four additional patients in the group receiving lorazepam followed by fentanyl required treatment for bradycardia or hypotension within 10 minutes of the beginning of the fentanyl infusion. When an infusion of lorazepam was added to the fentanyl infusion, hemodynamics remained stable; however, the reverse order produced a high level of bradycardia and hypotension.     

The Association of Raynaud Syndrome With β-Blockers: A Meta-Analysis

Vasospastic disorders of the digital circulation such as the Raynaud syndrome (RS) are known side effects of treatment of β-adrenergic blockade. The prevalence of RS in patients during treatment with β-blockers is not well defined. The objective of this meta-analysis is to assess the prevalence of RS in patients receiving β-blockers. A literature search was performed for studies dealing with RS and patients receiving β-blockers. The studies provided sufficient data to estimate the prevalence of RS in patients receiving β-blockers. A total of 13 eligible studies, contributing data on 1012 individuals, were included in this meta-analysis. For RS in patients receiving β-blockers, a pooled prevalence of 14.7% (95% confidence interval 0.076-0.236) were obtained. Statistically publication bias was not present (P = .877). Despite some heterogeneity, there is a possible indication of an association between RS and patients receiving β-blockers.     

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。     

Comparison of sufentanil-oxygen and fentanyl-oxygen anesthesia for mitral and aortic valvular surgery

The cardiovascular responses, speed of anesthetic induction, incidence of chest wall rigidity, need for anesthetic supplements (phentolamine, N20, and nitroprusside) to control intraoperative hypertension, and speed of postoperative recovery were measured and compared in 44 patients undergoing aortic and mitral valvular replacement with fentanyl O₂ or sufentanil-O₂ anesthesia. After a lorazepamatropine premedication and pancuronium pretreatment, fentanyl was administered intravenously at a rate of 400 jig/min and sufentanil at 200 μg/min until patients were unconscious; at this time they were given succinylcholine and their tracheas were intubated. After intubation, an amount of fentanyl or sufentanil equal to the dose producing unconsciousness was infused over the next 30 minutes, at which time the operation began. Additional fentanyl or sufentanil was given whenever systolic arterial blood pressure (SBP) increased more than 15% over preanesthetic values. When three successive supplemental doses of the narcotic failed to effectively decrease SBP, phentolamine was used to control pressure before and during bypass; after bypass, N20 (25% to 50%) or, if N20 was ineffective, nitroprusside was used. Average time of induction was 3.4 ± 0.3 for fentanyl and 1.0 ± 0.2 min (mean ± SD) for sufentanil. Chest wall rigidity occurred in 36% of patients in both groups. Total doses of fentanyl and sufentanil required for the entire operation were 113 ± 11 and 9.0 ± 0.4 μg/kg (mean ± SD), respectively. Heart rate, cardiac output, and mean right atrial pressure remained unchanged throughout the study in both groups. Mean arterial blood pressure (MBP) and SBP were significantly decreased during induction and after intubation in patients receiving sufentanil, but not fentanyl. Arterial pressure returned to control values prior to incision in patients receiving sufentanil. Neither group experienced a significant change in SBP after incision, sternotomy, or sternal spread. However, phentolamine was required in 32% and 68% of patients receiving fentanyl before and during bypass, respectively, but in 0% to 5% of those having sufentanil. Thirty-two percent of fentanyl patients required N₂0, and 23% nitroprusside after bypass for blood pressure control. Fourteen percent of patients receiving sufentanil required N₂0, and only 5% needed nitroprusside after bypass. The results of this study demonstrate that anesthetic doses of sufentanil result in less need for supplements and vasodilators during operation, but produce more hypotension during induction than fentanyl in patients having valve replacement.     

Technical performance of colonoscopy in patients sedated with nurse-administered propofol

OBJECTIVES: Nurse-administered propofol has gained attention as a safe and effective means of sedation for patients undergoing endoscopic procedures. However, little is known about the effect of propofol on the technical performance of colonoscopy. METHODS: Three separate studies were conducted. In the first study, we reviewed procedure notes from consecutive colonoscopies performed by a single experienced endoscopist at our hospital endoscopy unit on patients sedated with either nurse-administered propofol (n = 162) or midazolam/narcotic (n = 164). In the second study, 100 eligible colonoscopy outpatients were randomized to receive either nurse-administered propofol (n = 50) or midazolam/fentanyl (n = 50). In both studies, the measured parameters included visualization of the cecum, time required to reach the cecum, repositioning of the patient, and the application of abdominal counterpressure. In a third study, we reviewed the rate of cecal intubation and colonic perforation in the first 2357 patients in our unit receiving nurse-administered propofol. RESULTS: In the retrospective comparative study, there was no difference in the cecal intubation rate in those receiving propofol (99.4%) compared to those receiving midazolam/narcotic (97%; p= 0.1), and three of five failed cecal intubations in the latter group resulted from obstructing masses. Patients sedated with propofol were repositioned less frequently compared to those receiving midazolam/narcotic (3.7%vs 26.2%) (p < 0.0001). Abdominal pressure was employed in 9.9% of patients sedated with propofol compared to 19.5% (p= 0.01) of those given midazolam/narcotic. The mean time to reach the cecum was lower in the propofol group than in the midazolam/narcotic group (4.6 min vs 6.0 min, p= 0.002). In the prospective randomized study, the endoscopist intubated the cecum in all 100 patients. Patients in the propofol group were repositioned less frequently than those in the midazolam/fentanyl group (2%vs 24%, respectively, p= 0.001). The number of cases requiring abdominal counterpressure was not significantly different between the propofol and midazolam/fentanyl groups (12%vs 24%, respectively, p= 0.1). The mean time to reach the cecum in the propofol group (3.2 min) was similar to that in the midazolam/fentanyl group (3.8 min, p= 0.08). Among the first 2357 patients in our unit undergoing colonoscopy with nurse-administered propofol, the rate of complete colonoscopy was 99.2% and there were no perforations. CONCLUSION: Nurse-administered propofol sedation is safe and simplifies the technical performance of colonoscopy compared to midazolam/narcotic sedation.     

Antiatherogenic effects of β-adrenergic blocking agents: Theoretical,experimental, and epidemiologic considerations

Theoretical considerations and results from experimental studies in animal models suggest that long-term β-adrenergic blockade should be antiatherogenic. Some of these experimental results indicate that β-blockers could inhibit atherogenesis and thus prevent clinical events independently of any effects on blood pressure through concomitant reductions in heart rate, blood velocity and energy, endothelial permeability to lipoproteins, and the likelihood of plaque rupture. Any such independent inhibition of atherogenesis implies, in turn, that β-blockers might be more desirable than alternative antihypertensive therapies in persons at high risk for atherosclerotic diseases. Results of the three major trials directly comparing β-blockers to diuretics in the primary prevention of coronary heart disease among patients with hyportonsion were largely inconclusive. However, ancillary data from these and other trials are consistent in demonstrating that β-adrenergic blockade is associated with anti-coronary heart disease effects and, thus, is perhaps antiatherogenic. A definitive evaluation of the antiatherogenic effects of β-blockers is not forthcoming because no large clinical trials directly assessing the effect of these drugs on atherosclerosis have been done or are planned.     

舒芬太尼与芬太尼对小儿心脏手术乳酸水平影响的回顾性研究

目的:通过对非发绀先天性心脏病(先心病)小儿心脏手术中乳酸水平的大样本回顾分析,对比舒芬太尼与芬太尼复合麻醉乳酸水平以及高乳酸血症的发生率。方法:选择我院2006年10月至2008年11月期间实施的新生儿、婴幼儿心脏手术405例,年龄11～1095d平均(353.72±249.84)d,美国麻醉医师学会(ASA)Ⅰ～Ⅱ级。根据麻醉方法分成芬太尼组(F组,210例)和舒芬太尼组(S组,195例)。2组均为静吸复合麻醉,诱导麻醉F组芬太尼5～l0μg/kg,S组舒芬太尼0.5～1μg/kg;维持麻醉F组芬太尼总量(50.43±30.41)μg/kg,S组舒芬太尼(9.12±4.44)μg/kg,2组均间断吸入异氟烷(0.5%～1%),静脉注入咪达唑仑和哌库溴铵。收集切皮前(T1)、体外循环心脏复跳后10min(T2)、体外循环结束后15min(T3)、ICU1h(T4)、ICU8h(T5)、ICU24h(T6)6个时间点动脉血乳酸值,比较2组各个时间点高乳酸血症(乳酸值≥3mmol/L)的发生率和乳酸值变化趋势。结果:全组T2点乳酸值明显高于其它各点(P0.01),并且与年龄、体质量呈明显负相关性,与手术时间、体外循环时间、阻断主动脉时间、拔气管导管时间及ICU停留时间等呈明显正相关性(P0.01)。S组年龄、体质量、手术时间、体外循环时间及阻断主动脉时间、拔气管导管时间及ICU停留时间与F组比较差异无统计学意义(P0.05)。S组T1、T2、T3及T4点乳酸值均明显低于F组(P0.01);S组T2、T3点高乳酸血症发生率明显低于F组(P0.05)。结论:手术中,与芬太尼比较,舒芬太尼能够降低乳酸水平,明显降低高乳酸血症发生率,对改善非发绀先心病小儿心脏手术中的乳酸代谢有明显积极作用。     

Catecholamine responses to anesthetic induction with fentanyl and sufentanil

In a randomized study, the authors examined the changes in plasma epinephrine and norepinephrine concentrations associated with induction of anesthesia and surgery in 33 patients with good ventricular function undergoing elective coronary artery surgery. After premedication with morphine and scopolamine, patients received either fentanyl, 100 μg/kg (n = 16), or sufentanil, 15 μg/kg, (n = 17), intravenously (IV), over 10 minutes to induce anesthesia. Metocurine, 0.42 mg/kg, IV, produced muscle relaxation. Arterial blood for plasma catecholamine determinations was drawn prior to induction, every two minutes throughout induction, one minute following endotracheal intubation, and one minute after sternotomy. Plasma epinephrine concentration was unchanged with either induction agent. Plasma norepinephrine concentration increased significantly after administration of either narcotic, peaked between six and ten minutes into induction, and returned to the preinduction value after intubation. Induction-related changes in arterial pressure and pulmonary capillary wedge pressure were significantly correlated with changes in the logarithm of plasma norepinephrine concentration. Similar degrees of endogenous norepinephrine release appear to accompany induction with equipotent doses of fentanyl and sufentanil in patients premedicated with morphine and scopolamine. Norepinephrine release may influence the hemodynamic response to induction with narcotics.     

Efficacy of low and standard midazolam doses for gastroscopy. A randomized, double-blind study

AIM: To evaluate the efficacy and safety of two different doses of intravenous midazolam (35 and 70 microg/kg) compared to placebo in patients undergoing gastroscopy. PATIENTS AND METHODS: Sixty patients scheduled for diagnostic gastroscopy were selected according to factors previously reported to affect tolerance (Eur J Gastroenterol Hepatol 1999; 11:201-204) and were randomly assigned to receive premedication with midazolam 35 microg/kg iv, midazolam 70 microg/kg iv or placebo iv. Oxygen saturation was continuously monitored during the procedure. Patients' tolerance, time to discharge and post-sedative inconvenience were evaluated using visual analogue scales and a questionnaire. RESULTS: Patients receiving either dose of midazolam showed better tolerance of gastroscopy than those receiving the placebo. Fewer patients receiving 70 or 35 microg/kg of midazolam were reluctant to undergo a further gastroscopy compared to those receiving the placebo (2, 1 and 9 patients respectively, P = 0.01). Compared to patients receiving midazolam 70 microg/kg, those receiving midazolam 35 microg/kg were discharged earlier (29.3+/-14.4 versus 43.1+/-12.4 min respectively, P < 0.001), experienced less post-sedative inconvenience (8 versus 15 patients slept for > 1 h at home respectively, P = 0.02), and suffered fewer clinically relevant desaturation episodes (< 90%) (0 versus 5 patients respectively, P = 0.04). CONCLUSIONS: Low doses of intravenous midazolam (35 microg/kg) are adequate and safe when sedation is indicated for gastroscopy.     

Effects of steal-prone anatomy on intraoperative myocardial ischemia. The SPI Research Group.

OBJECTIVES. Our study objective was to determine whether the presence of steal-prone anatomy conferred an increased risk in the development of intraoperative myocardial ischemia. BACKGROUND. Coronary artery steal of collateral blood flow has been demonstrated for many vasodilators, including isoflurane, the most commonly used inhalational anesthetic agent in the United States. It has been postulated that patients with steal-prone anatomy (total occlusion of one coronary artery that is supplied distally by collateral flow from another coronary artery with a > or = 50% stenosis) may be particularly at risk for the development of intraoperative myocardial ischemia when an anesthetic with a vasodilator property is being administered. METHODS. We evaluated the risk of myocardial ischemia under isoflurane anesthesia (vs. a high dose narcotic technique using sufentanil) using continuous intraoperative electrocardiography and transesophageal echocardiography in patients with and without steal-prone anatomy undergoing coronary artery bypass graft surgery. RESULTS. Sixty-two (33%) of the 186 patients had steal-prone anatomy: in 5 (8%) the collateral-supplying vessel was > or = 50% to 69% stenosed, in 24 (39%) it was > or = 70% to 89% stenosed and in 33 (53%) it was > or = 90% stenosed. The incidence of ischemia (transesophageal echocardiography or intraoperative electrocardiography, or both) was similar in patients with and without steal-prone coronary anatomy (18 [29%] of 62 patients vs. 39 [31%] of 124 patients, p = 0.87, 95% confidence interval = -0.13 to 0.17). The incidence of intraoperative ischemia was similar in patients who received isoflurane or sufentanil anesthesia (20 [32%] of 62 patients vs. 37 [30%] of 124 patients, p = 0.87). The incidence of tachycardia and hypotension was low (increases in heart rate = 9.8%, and decreases in systolic blood pressure = 10.8% of total monitoring time during the prebypass period compared with preoperative baseline values). The incidence of adverse cardiac outcome was similar in patients with and without preoperative steal-prone coronary anatomy (4 [7%] of 62 patients vs. 14 [11%] of 124 patients, p = 0.53). CONCLUSIONS. These findings demonstrate that under strict hemodynamic control the presence of steal-prone anatomy does not confer an increased risk in the development of intraoperative myocardial ischemia.     

不同剂量盐酸戊乙奎醚对体外循环冠脉搭桥手术患者心肌保护作用

目的 比较两种不同剂量盐酸戊乙奎醚对体外循环下行冠脉搭桥手术患者心肌保护作用.方法 2011年5月至2013年5月择期行冠脉搭桥手术患者75例,随机分成3组：对照组（25例）,给予等量生理盐水;小剂量组（25例）,戊乙奎醚 0.05 mg/kg;大剂量组（25例）,戊乙奎醚0.1 mg/kg.比较三组冠脉搭桥手术患者不同时间点的心肌肌钙蛋白I（cTnI）、肌酸磷酸激酶同工酶MB（CK-MB）、肌酸激酶（CK）、谷草转氨酶（AST）、α-羟丁酸脱氢酶（α-HBDH）、乳酸脱氢酶（LDH）浓度的变化.结果 三组患者cTnI、CK-MB、CK、AST、α-HBDH、LDH浓度,主动脉开放后1 h（T1）及主动脉开放后24 h（T2）与麻醉诱导前（T0）相比明显升高,差异均有统计学意义（P〈0.05）;T1、T2时间点组间比较,戊乙奎醚大、小剂量组低于对照组,差异有统计学意义（P〈0.05）,戊乙奎醚大剂量组与小剂量组相比差异无统计学意义（P＆gt;0.05）.结论 盐酸戊乙奎醚对体外循环冠脉搭桥手术患者具有心肌保护作用,安全性好,值得临床推广和应用,剂量上大剂量组并不优于小剂量组.     

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.     

Clinical evaluation of the short half-life injectable benzodiazepine midazolam, and of the specific antagonist flumazenil in upper digestive tract endoscopy.

In a first step, midazolam 0.1 mg/kg, midazolam 0.05 mg/kg and diazepam 0.15 mg/kg administered intravenously were blindly evaluated as a sedating preparation in 3 groups of each 30 patients undergoing gastroscopy. Although amnesia is better with midazolam 0.1 mg/kg, the induced sedation is protracted, which is not to be wished in ambulatory patients. On the other side, diazepam 0.15 mg/kg was locally less well tolerated. Taking into consideration the efficacy and the general and local tolerance, the dose of midazolam 0.05 mg/kg seems the best compromise. In a second step, the specific benzodiazepine antagonist flumazenil was blindly evaluated at two intravenous doses, 1 mg and 0.5 mg, against placebo for reversal of midazolam (0.1 mg/kg) induced sedation in gastroscopy patients. 1 mg of flumazenil (and to a lesser degree 0.5 mg) suppresses the sedation and amnesia induced by midazolam and normalizes attention and sensori-motor functions. However a certain degree of resedation can reappear 45-60 min. after the administration of flumazenil. Though this phenomenon did not alter the tests measuring attention and sensorimotor functions and the recovery of memory (contrary to placebo), it incites to be cautious when the drug is given to ambulatory patients.     

Etomidate and midazolam for reduction of anterior shoulder dislocation: a randomized,controlled trial

STUDY OBJECTIVE: We determine whether patients with acute, anterior shoulder dislocation undergoing emergency department procedural sedation and analgesia (PSA) with intravenous etomidate would experience a reduced time of impaired consciousness when compared with a group of patients receiving intravenous midazolam. METHODS: This study was a prospective, double-blinded, randomized, institutional review board-approved trial of ED patients with anterior shoulder dislocation. Patients were randomized to receive intravenous boluses of etomidate (0.1 mg/kg) or midazolam (0.033 mg/kg) during PSA. The primary outcome for comparison was PSA duration. RESULTS: Forty-six patients with anterior shoulder dislocation were enrolled: 22 in the etomidate group and 24 in the midazolam group. Three patients sustained reduction without physician or sedative intervention. Two patients were excluded from protocol because of unavailable study drug or fracture dislocation. The median lowest modified postanesthetic recovery score observed during PSA was 5 (95% confidence interval [CI] 4 to 7) in the etomidate group and 6 (95% CI 6 to 7) in the midazolam group. The median time of PSA for patients receiving etomidate was 10 minutes (95% CI 8 to 15) compared with 23 minutes (95% CI 16 to 30) for patients receiving midazolam, with a difference between the group medians of 13 minutes (95% CI 5 to 22). Reduction success was achieved in 37 (90%) of 41 patients: 2 did not experience reduction with etomidate and 2 did not experience reduction with midazolam. There were 15 PSA complications reported. CONCLUSION: Etomidate provides effective PSA for reduction of ED patients with anterior shoulder dislocation. When compared with midazolam, etomidate use confers a significantly shorter period of PSA.     

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。     

The role of flumazenil in outpatient transesophageal echocardiography.

BACKGROUND: Benzodiazepines used for transesophageal echocardiography (TEE) sedation may be associated with postprocedural psychomotor effects that are undesirable. HYPOTHESIS: We hypothesize that flumazenil can reverse cognitive and motor effects from benzodiazepine, promoting earlier return to baseline function. METHODS: We prospectively evaluated the cognitive and motor function of patients who did or did not receive flumazenil following TEE. Patients' gait, level of drowsiness, and recall of items learned before and after benzodiazepine administration were evaluated before TEE, as well as immediately and 30 min after the procedure. RESULTS: Of 207 patients (123 men and 84 women), 93 (45%) were given flumazenil 0.2 or 0.4 mg intravenously, and 113 (55%) were not. The baseline characteristics of the patients who received flumazenil were not significantly different from those who did not receive flumazenil, with the exception of a higher mean dosage of midazolam administered to the flumazenil group. In addition, patients in the flumazenil group appeared more drowsy immediately following TEE. When adjusted for age and midazolam dosage, there were no differences, at any time, between the two groups in gait or recall of items learned prior to sedation. however, at 30 min following TEE, the flumazenil group was able to recall a larger number of new items learned immediately after the procedure (1.92/3 vs. 1.61/3, p = 0.02) than did patients in the group not receiving flumazenil. No adverse effects were encountered in any patient. CONCLUSION: Flumazenil appears safe and effective in reversing anterograde amnesic effects of benzodiazepine following TEE, but has no effects on retrograde amnesia and does not promote earlier return of motor function to baseline. It is useful in clinical situations where high dosages of benzodiazepine have been used and/or excessive drowsiness is evident following TEE. Routine use of the drug, however, is not necessary.     

Impact of flumazenil on recovery after outpatient endoscopy: a placebo-controlled trial

BACKGROUND: Flumazenil is an imidazobenzodiazepine that blocks the central effects of benzodiazepines by competitive interaction at the receptor level. In this study we assessed the impact of flumazenil use on postsedation observation time in outpatients undergoing endoscopy. METHODS: Sixty outpatients received midazolam for conscious sedation and were randomized after endoscopy to receive intravenous flumazenil (0.1 mg/mL) or placebo until awake or a total of 10 mL was given. All patients were assessed using various psychomotor and cognitive tests at baseline and at 5, 15, 30, 45 and 60 minutes after flumazenil or placebo was administered. RESULTS: The two groups were similar in age, gender, midazolam dose (mg/kg), vital signs, and baseline parameters. The average dose of flumazenil given was 0.41 mg. Sedation scores returned to presedation levels earlier in the flumazenil group, with significant differences compared to placebo at 5 minutes (84.6% vs. 24.2%), 15 minutes (88. 5% vs. 57.6%) and 30 minutes (96.2% vs. 66.7%). Other parameters tested were not significantly different for patients receiving placebo compared to those given flumazenil. Sedation scores returned to baseline earlier than other psychomotor and cognitive tests in both groups. Flumazenil reduced the mean observation time from 23.5 minutes to 8.3 minutes (p < 0.0005), a difference of 15.2 minutes (64.7%) based on sedation score. CONCLUSIONS: Flumazenil significantly reduces postsedation observation time. Actual cost savings will vary depending on staff and facility capacity, patient volume, flumazenil cost, and unit cost of observation time.     

The effects of dexmedetomidine on attenuation of stress response to endotracheal intubation in patients undergoing elective off-pump coronary artery bypass grafting

This study was designed to study the efficacy of intravenous dexmedetomidine for attenuation of cardiovascular responses to laryngoscopy and endotracheal intubation in patients with coronary artery disease. Sixty adult patients scheduled for elective off-pump coronary artery bypass surgery were randomly allocated to receive dexmedetomidine (0.5 mcg/kg) or normal saline 15 min before intubation. Patients were compared for hemodynamic changes (heart rate, arterial blood pressure and pulmonary artery pressure) at baseline, 5 min after drug infusion, before intubation and 1, 3 and 5 min after intubation. The dexmedetomidine group had a better control of hemodynamics during laryngoscopy and endotracheal intubation. Dexmedetomidine at a dose of 0.5 mcg/kg as 10-min infusion was administered prior to induction of general anaesthesia attenuates the sympathetic response to laryngoscopy and intubation in patients undergoing myocardial revascularization. The authors suggest its administration even in patients receiving beta blockers.