全麻期间机械通气对患者心功能的影响

目的 评价全麻期间机械通气对患者心功能的影响.方法 选择鼓室成形术ASA Ⅰ或Ⅱ级患者53例,随机分为机械通气组(M组,n=28)和自主呼吸组(S组,n=25).M组麻醉诱导气管插管后行机械通气;S组采取麻醉慢诱导气管插管后保留自主呼吸.术中维持BIS 40～60.于气管插管前、气管插管后1、5、10、20、40、60、90、120及150 min时记录心率(HR)、平均动脉压(MAP)、脉搏血氧饱和度(SpO2)、心输出量(CO)及每搏量(SV);并于气管插管后各时点记录呼气末二氧化碳分压(PETCO2)、潮气量(VT)、呼吸频率(RR)及气道峰压(Ppeak).结果 与S组比较,M组CO、SV、HR及MAP差异无统计学意义(P>0.05),SpO2、Vr及Ppeak较高,RR较慢,PETCO2较低(P<0.05),但均在正常范围.结论 临床麻醉中短时间机械通气对患者的心功能无明显影响.     

The effects of low-flow sevoflurane and isoflurane anesthesia on renal function in patients with stable moderate renal insufficiency

Sevoflurane degrades to Compound A, which is nephrotoxic in rats. Therefore, the renal effects of Compound A is an area of intense debate. We investigated the effects of low-flow sevoflurane and isoflurane anesthesia on renal function in patients with stable renal insufficiency. Seventeen patients with a serum creatinine level of more than 1.5 mg/dL were anesthetized with sevoflurane or isoflurane at a total flow of 1 L/min. Serum creatinine and blood urea nitrogen were measured before anesthesia and again 1, 2, 3, 5, 7, and 14 days after anesthesia. The 24-h creatinine clearance was measured before anesthesia and 7 days after anesthesia. There were no significant differences in the blood urea nitrogen levels, serum creatinine concentrations, or creatinine clearance before and after anesthesia within each group. These results suggest that sevoflurane and isoflurane have similar effects on renal function in patients with moderately impaired renal function. Further study of the effects of low-flow sevoflurane anesthesia on impaired renal function with a larger sample size than ours is required to resolve the issue of sevoflurane safety in patients with renal insufficiency. IMPLICATIONS: The serum creatinine and blood urea nitrogen data indicate that, for exposures of <130 ppm/h in Compound A inspired area under the curve, renal effects of low-flow sevoflurane are similar to those of isoflurane in patients with stable renal insufficiency.     

Pulmonary perfusion during anesthesia and mechanical ventilation

Cardiac output and the pulmonary perfusion can be affected by anesthesia and by mechanical ventilation. The changes contribute to impeded oxygenation of the blood. The major determinant of perfusion distribution in the lung is the relation between alveolar and pulmonary capillary pressures. Perfusion increases down the lung, due to hydrostatic forces. Since atelectasis is located in dependent lung regions, perfusion of non-ventilated lung parenchyma is common, producing shunt of around 8-10% of cardiac output. In addition, non-gravitational inhomogeneity of perfusion, that can be greater than the gravitational inhomogeneity, adds to impeded oxygenation of blood. Essentially all anaesthetics exert some, although mild, cardiodepressant action with one exception, ketamine. Ketamine may also increase pulmonary artery pressure, whereas other agents have little effect on pulmonary vascular tone. Mechanical ventilation impedes venous return and pushes blood flow downwards to dependent lung regions, and the effect may be striking with higher levels of PEEP. During one-lung anesthesia, there is shunt blood flow both in the non-ventilated and the ventilated lung, and shunt can be much larger in the ventilated lung than thought of. Recruitment manoeuvres shall be directed to the ventilated lung and other physical and pharmacological measures can be taken to manipulate blood flow in one lung anesthesia.     

Hemodynamic effects of metocurine during isoflurane anesthesia

Anesthesia was induced in 42 adults with thiopentone 3-7 mg/kg i.v. and maintained with isoflurane at a constant inspired concentration of 1-2%. After 30 min of hemodynamic stabilization with continuous muscle relaxation and an absence of surgical stimulation, each patient was randomly assigned to one of four metocurine dosage groups: I - control (n = 11); II - 0.2 mg/kg (n = 10); III - 0.3 mg/kg (n = 10); and IV - 0.4 mg/kg (n = 11). There were no significant hemodynamic changes in Groups I or II. In Groups III and IV mean arterial pressure (MAP) decreased 32% and 26% respectively, and systemic vascular resistance (SVR) decreased 42% and 36%, respectively (P less than 0.01). In Group IV, an increase of 24% in cardiac output was also significant (P less than 0.05). These results, especially in Group IV patients, stand in marked contrast to the lack of hemodynamic effects produced by metocurine during balanced anesthesia.     

七氟醚与异氟醚吸入麻醉对肾移植患者术后早期肾功能的影响比较

目的 比较七氟醚与异氟醚吸入麻醉对肾移植患者术后早期肾功能影响的差异,为吸入麻醉药的选择提供借鉴.方法 对106例全身麻醉下行同种异体肾移植的终末期肾病患者的临床资料进行分析,按照吸入麻醉药物的不同,将患者分成七氟醚组(74例)和异氟醚组(32例),比较分析术后早期肾功能变化特点.结果 与术前相比,两组患者术后第1日、...     

三种麻醉方法对肾移植病人免疫功能的影响

目的 比较三种麻醉方法对肾移植病人术中免疫功能的影响。方法 39例尿毒症且无其他免疫系统疾患的病人随机分为三组,Ⅰ组为连续硬膜外麻醉组(n=13),Ⅱ组为蛛网膜下腔.硬膜外联合麻醉组(n=13),Ⅲ组为静吸复合全身麻醉组(n=13),所有病人均于麻醉后开始输血,根据病人入室血压决定输血量,范围为600-800 ml。三组病人于麻醉前、麻醉后、输血前、输血后30min、输血后1 h、开放动静脉、术毕、术后1 d和3 d检测外周静脉血CD+3、CD+4、CD+8、CD+4,CD+8和IgG、IgA、IgM、C3、C4值。结果 三组病人平均输血量为700 ml,差异无显著性。三组组间免疫球蛋白及补体比较各时点对应检测值差异无显著性(P>0.05);三组组内免疫球蛋白(IgG、IgA、IgM)及补体(C3、C4值)麻醉后各时间点与麻醉前相比,差异无显著性(P>0.05)。Ⅰ组和Ⅱ组,麻醉后CD+3、CD+4、CD+4/CD+8与麻醉前相比,差异无显著性(P>0.05);而输血后CD+3、CD+4、CD+4/CD+8值下降明显,与麻醉前、输血前相比,差异有显著性(P<0.05-0.01),术后1 d回升、3 d处于高水平;CD+8各时间点与麻醉前相比,无统计学意义(JP>0.05)。Ⅲ组CD+3、CD+4、CD+4/CD+8值麻醉后开始下降,与麻醉前、输血前比较,差异有显著性(P<0.05),输异体血后下降更明显,差异非常显著(P<0.01),术后第一天仍未恢复     

丙泊酚或异氟醚麻醉对单肺通气时氧化应激反应的影响

目的 观察丙泊酚或异氟醚麻醉对单肺通气(OLV)时氧化应激反应的影响.方法 48例择期行食管癌根治术患者,随机分为丙泊酚单肺通气组(Pro-OLV组)、异氟醚单肺通气组(Iso-OLV组)、丙泊酚双肺通气组(Pro-TLV组)和异氟醚双肺通气组(Iso-TLV组),每组12例.于开胸前(T0)、OLV后(TLV组于开胸后)30 min(T1)、90 min(T2)、150 min(T3)、手术结束时(T4)测定血清超氧化物歧化酶(SOD)、丙二醛(MDA)及NO浓度.结果 与T0时比较,OLV组T1～T4时的SOD活性降低,MDA浓度及NO浓度升高(P<0.01),而TLV组无明显变化.与TLV组比较,OLV组T1～T4时的SOD活性降低,MDA及NO浓度升高(P<0.01).结论 丙泊酚或异氟醚麻醉均不能减轻OLV时氧化应激反应.     

Comparison of renal function following anesthesia with low-flow sevoflurane and isoflurane.

STUDY OBJECTIVE: To evaluate postoperative renal function after patients were administered sevoflurane under conditions designed to generate high concentrations of compound A. STUDY DESIGN AND SETTING: A multicenter (11 sites), multinational, open-label, randomized, comparative study of perioperative renal function in patients who have received low-flow (< or = 1 L/min) sevoflurane or isoflurane. PATIENTS: 254 ASA physical status I, II and III patients requiring endotracheal intubation for elective surgery lasting more than 2 hours. INTERVENTIONS: After induction, low-flow anesthesia was initiated at a flow rate < or = 1 L/min. Blood and urine samples were studied to assess postoperative renal function. MEASUREMENTS AND MAIN RESULTS: Measurements of serum BUN and creatinine, and urine glucose, protein, pH, and specific gravity were used to assess renal function preoperatively and up to 3 days postoperatively. Serum inorganic fluoride ion concentration was measured at preinduction, emergence, and 2, 24 and 72 hours postoperatively. Compound A concentrations were measured at two sites for those patients receiving sevoflurane. Adverse experience data were analyzed. One hundred eighty-eight patients were considered evaluable (98 sevoflurane and 90 isoflurane). Peak serum fluoride concentrations were significantly higher after sevoflurane (40 +/- 16 microM) than after isoflurane (3 +/- 2 microM). Serum creatinine and BUN decreased in both groups postoperatively; glucosuria and proteinuria occurred in 15% to 25% of patients. There were no clinically significant differences in BUN, creatinine, glucosuria, and proteinuria between the low-flow sevoflurane and low-flow isoflurane patients. CONCLUSIONS: There were no statistically significant differences in the renal effects of sevoflurane or isoflurane in surgical patients undergoing low-flow anesthesia for up to 8 hours. Low-flow sevoflurane anesthesia under clinical conditions expected to produce high levels of compound A appears as safe as low-flow isoflurane anesthesia.     

Neuromuscular effects of pipecuronium during sevoflurane anesthesia compared with isoflurane and enflurane anesthesia

We evaluated the neuromuscular effects of pipecuronium during anesthesia with equipotent concentrations of either sevoflurane, isoflurane or enflurane.Twenty-seven patients scheduled for minor elective otolaryngeal or plastic surgery were studied and randomly assigned to 3 groups, one group per anesthetic agent. Anesthesia was induced with thiamylal 5mg·kg^–1 and the trachea was intubated with succinylcholine 1mg·kg^–1, then anesthesia was maintained with 60% nitrous oxide in oxygen and sevolfurane, isoflurane or enflurane, depending on the group. Neuromuscular blocking effects were monitored by recording the electromyographic activity of the adductor pollicis muscle from supramaximal stimulation of the ulnar nerve at 10-s intervals. Pipecuronium 40µg·kg^–1 was administered when electromyographic activity had reached a stable state, 30min after succinylcholine administration. The maximum effect (% block of control) and clinical duration (time to 25% recovery) of pipecuronium were 99.1 ± 1.4% and 63.7 ± 14.7min (mean ± S.D.) for sevoflurane, 99.0 ± 2.0% and 60.9 ± 20.5min for isoflurane, and 98.0 ± 2.5% and 62.8 ± 28.7min for enflurane, respectively. There were no significant differences in these values between the anesthetics. Cardiovascular stimulant effects were not observed in any of the groups.We conclude that the effect of pipecuronium under seveflurane anesthesia is similar to that under isoflurane and enflurane anesthesia.(Nakao Y, Ohno M, Imai M, et al.: Neuromuscular effects of pipecuronium during sevoflurane anesthesia compared with isoflurane and enflurane anesthesia. J Anesth 7: 405--410, 1993)     

Losartan increases renal blood flow during isoflurane anesthesia in sheep

BACKGROUND: Inhaled anesthetics cause a transient reversible depression of renal function by direct renal effects or indirectly by changes in neurohumoral systems or cardiovascular performance. When the sympathetic nervous activity is decreased during anesthesia, other vasoactive systems like vasopressin (AVP) and particularly the renin angiotensin system (RAS) are of importance for blood pressure maintenance. Little is known about how the renal circulation is affected by angiotensin receptor blockade during isoflurane anesthesia. METHODS: The study was performed on isoflurane anesthetized sheep equipped with flow probes (placed around a femoral and a renal artery) and a pulmonary artery catheter. During stable conditions the sheep were given one or more of the following substances: isotonic saline (NaCl); losartan (LOS) 10 mg x kg(-1); prazosin (PRAZ) 0.2 mg x kg(-1) and a vasopressin V1-receptor antagonist (AVP-a) 10 microg x kg(-1). RESULTS: LOS and AVP-a did not affect mean arterial pressure (MAP), whereas PRAZ lowered MAP significantly (from 98+/-12 to 65+/-7 mmHg). Renal blood flow (RBF) increased after LOS treatment (148+/-34 to 222+/-33 ml x min(-1)). The other substances were without effect on RBF. Femoral blood flow remained unchanged after all treatments. CONCLUSION: We conclude that the sympathoadrenal system is still the major determinant for blood pressure maintenance during isoflurane anesthesia in sheep. The apparently increased activity of the renin angiotensin system in this situation causes a reduction in renal blood flow, which is counteracted by angiotensin II AT1-receptor blockade.     

The effects of prolonged low-flow sevoflurane anesthesia on renal and hepatic function

We assessed the effects of prolonged low-flow sevoflurane anesthesia on renal and hepatic functions by comparing high-flow sevoflurane with low-flow isoflurane anesthesia. Thirty patients scheduled for surgery of > or =10 h in duration randomly received either low-flow (1 L/min) sevoflurane anesthesia (n = 10), high-flow (6-10 L/min) sevoflurane anesthesia (n = 10), or low-flow (1 L/min) isoflurane anesthesia (n = 10). We measured the circuit concentrations of Compound A and serum fluoride. Renal function was assessed by blood urea nitrogen, serum creatinine, creatinine clearance, and urinary excretion of glucose, albumin, protein, and N:-acetyl-beta-D-glucosaminidase. The hepatic function was assessed by serum aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, alkaline phosphatase, and total bilirubin. Compound A exposure was 277 +/- 120 (135-478) ppm-h (mean +/- SD [range]) in the low-flow sevoflurane anesthesia. The maximum concentration of serum fluoride was 53.6 +/- 5.3 (43.4-59.3) micromol/L for the low-flow sevoflurane anesthesia, 47.1 +/- 21.2 (21.4-82.3) micromol/L for the high-flow sevoflurane anesthesia, and 7.4 +/- 3.2 (3.2-14.0) micromol/L for the low-flow isoflurane anesthesia. Blood urea nitrogen and serum creatinine were within the normal range, and creatinine clearance did not decrease throughout the study period in any group. Urinary excretion of glucose, albumin, protein, and N:-acetyl-beta-D-glucosaminidase increased after anesthesia in all groups, but no significant differences were seen among the three groups at any time point after anesthesia. Lactate dehydrogenase and alkaline phosphatase on postanesthesia Day 1 were higher in the high-flow sevoflurane group than in the low-flow sevoflurane group. However, there were no significant differences in any other hepatic function tests among the groups. We conclude that prolonged low-flow sevoflurane anesthesia has the same effect on renal and hepatic functions as high-flow sevoflurane and low-flow isoflurane anesthesia. Implications: During low-flow sevoflurane anesthesia, intake of Compound A reached 277 +/- 120 ppm-h, but the effect on the kidney and the liver was the same in high-flow sevoflurane and low-flow isoflurane anesthesia.     

两种麻醉方法下食道癌根治术患者单肺通气期间肺内分流的比较

目的 比较食管癌根治术患者异丙酚-瑞芬太尼靶控静脉麻醉与异氟醚麻醉下单肺通气（OLV）期间肺内分流的变化。方法 择期行中、下段食管癌左侧开胸切除术患者24例，年龄42，69岁，ASAⅠ或Ⅱ级。随机均分为2组：异丙酚．瑞芬太尼组（PR组）和异氟醚组（ISO组）。PR组靶控输注异丙酚和瑞芬太尼，血浆靶浓度分别为3．2μg／ml和4．5ng／ml；ISO组吸入异氟醚（呼气末浓度为1．5％～2．5％），间断静脉注射芬太尼2μg／kg。持续监测ECG、平均动脉压（MAP）、SpO2、听觉诱发电位指数（AAI）、心脏指数（CI）、气道压（Paw）。麻醉诱导后，插入右双腔支气管导管，分别于平卧位漂浮导管置人后10min（T0）、右侧卧位双肺通气10min（T1）、单肺通气15、30、60、90min（T2～T5）进行动脉血及混合静脉血血气分析，计算肺内分流率（Q0／Q1）。结果 两组术中AAI均低于30，PaCO2、pH在正常范围内，组间各时点AAI、PaCO2、pH和Paw比较差异无统计学意义。与T0相比，两组T2-5时Paw升高，T1-5时Qa／Qt增加，于T2达到高峰；PaO2降低，于T2降至最低（P〈0．05），而CI差异无统计学意义（P〉O．05）。与ISO组比较，T2-5时PR组Qa／Qt降低（P〈0．05），PaO2差异无统计学意义。结论 与异氟醚麻醉比较，异丙酚-瑞芬太尼麻醉在OLV期间可减少食管癌根治术患者肺内分流，但对PaO2的影响不明显。     

Effects of fenoldopam on renal blood flow and systemic hemodynamics during isoflurane anesthesia.

The authors compared the systemic hemodynamic and renal vascular effects of hypotension induced by fenoldopam with those produced by the most commonly used hypotensive agent, sodium nitroprusside, in 10 dogs. Mean arterial pressure decreased 26% +/- 3% from control following infusion with fenoldopam, and 30% +/- 2% following infusion with sodium nitroprusside (these decreases were not significantly different between the groups). Renal blood flow (RBF) was preserved during fenoldopam-induced hypotension (214 +/- 16 mL/min at baseline and 197 +/- 16 mL/min after fenoldopam-induced hypotension). In contrast, RBF decreased from 223 +/- 17 mL/min to 167 +/- 12 mL/min during sodium nitroprusside-induced hypotension (P less than 0.02). The differences in RBF between the two groups occurred in spite of the fact that cardiac output and pulmonary capillary wedge pressure were kept similar between the two groups. The authors conclude that fenoldopam, a selective dopamine1 (DA1) receptor agonist, preserves blood flow to the kidney during induced hypotension. On the other hand, sodium nitroprusside is a nonselective arteriolar and venous vasodilator that redistributes blood flow away from the kidneys during induced hypotension.     

全麻下单肺通气对肺功能的影响

目的　探讨单肺通气状况的最佳呼吸方式。方法　 60例 ASA ～ 级开胸病人单肺麻醉时 ,在分钟通气量设定的条件下 ,随着吸气时间相对延长 (通过降低呼吸频率和吸∶呼比值 )的不同通气条件变化 ,对单肺功能和血气分析的影响进行了临床研究。结果　单肺通气时 ,在呼吸频率 =12次 /分 ,吸∶呼比值 =1∶ 1时 ,通气侧肺顺应性、实际分钟通气量和脉搏血氧饱和度明显改善 ,血气结果最佳 ,与双肺通气相比较无显著性差异 ( P>0 .0 5 ) ;气道压力显著降低 ,与单肺通气其它通气条件相比较有显著性降低 ( P<0 .0 5 )。但过分降低呼吸频率 ( RR<10次 /分 )达到的效果会适得其反。结论　在单肺通气使用麻醉呼吸器时 ,相对降低呼吸频率 ( RR=12次 /分 )、相对延长吸气时间 ( I∶ E=1∶ 1.5 ) ,可达到提高肺顺应性和通气量 ,降低气道压力 ,提高血氧和降低二氧化碳分压的良好效果     

Supraspinal pupillary effects of intravenous and epidural fentanyl during isoflurane anesthesia

BACKGROUND AND OBJECTIVES: Epidural fentanyl has been shown to gain rapid access to the circulation resulting in supraspinal effects. We compared the supraspinal effects of fentanyl via epidural versus intravenous (IV) routes, during isoflurane anesthesia. Supraspinal fentanyl effect was evaluated as a reduction of pupillary reflex dilation (PRD) measured with infrared pupillometry. METHODS: Eighteen patients undergoing abdominal procedures were studied during combined epidural and general anesthesia. General anesthesia was provided by 0.55 to 0.70% end-tidal isofurane in air:oxygen (50:50). Sensory block of the surgical field was established with bupivacaine 0.375% and confirmed by absence of PRD to cutaneous stimulation. A high cervical dermatome was then stimulated (60 to 70 mA) at 5-minute intervals via cutaneous needle electrodes, and PRD was measured with each stimulation, using infrared pupillometry. Baseline PRD was determined and then a randomized injection of cpidueral saline (n = 6), epidural fentanyl 3 microg/kg (n = 6), or IV fentanyl 3 microg/kg (n = 6) was given. Subsequently, PRD was measured at 5, 10, 20, 30, 40, 60, and 80 minutes. Maximum change in PRD and time to maximum change were calculated for each group. RESULTS: Following epidural injection, suppression of PRD was highly variable among subjects. The maximum suppression was 70+/-15% at 23.3+/-10.3 minutes for the epidural group and 96+/-3% at 10.8+/-7.4 min for the IV group (P<.0001). Epidural saline produced no effect. CONCLUSIONS: Supraspinal effects of epidural fentanyl can be assessed during general anesthesia using infrared pupillometry. Epidural fentanyl 3 microg/kg produces significant but variable supraspinal effects during 0.5 minimum alveolar concentration isoflurane anesthesia.     

孕早期异氟醚麻醉对子代大鼠认知功能的影响

目的 评价孕早期异氟醚麻醉对子代大鼠认知功能的影响.方法 孕5～7d的SD大鼠30只,采用随机数字表法,将其随机分为3组(n=10):正常对照组(C组)、吸入异氟醚4h组(Ⅰ1组)和吸入异氟醚8h组(Ⅰ2组).Ⅰ1组和Ⅰ2组分别吸入95％氧气-1.4％异氟醚4h和8h,氧流量2L/min,C组吸入95％氧气8h.分别于出生后20、30 d取5只母鼠的子鼠,采用Morris水迷宫实验测定认知功能,持续7d,然后处死子代大鼠,分离海马组织,测定N-甲基-D-天冬氨酸受体2B亚基mRNA及其蛋白的表达水平.结果 3组子代大鼠水迷宫实验结果、N-甲基-D-天冬氨酸受体2B亚基mRNA及其蛋白表达水平差异均无统计学意义(P＞0.05).结论 孕早期异氟醚麻醉对子代大鼠认知功能无影响.