Questioning the cardiocirculatory excitatory effects of opioids under volatile anaesthesia

Background. Opioid-induced hyperalgesia has been demonstratedin awake animals. We observed an increased haemodynamic reactivityin response to noxious stimuli in rats under sevoflurane anaesthesiatreated with a very low dose of sufentanil. The aim of thisinvestigation was to determine whether the two phenomena sharea common origin: an opioid-induced excitatory reaction. To addressthis, we administered several drugs with proven efficacy inopioid hyperalgesia to rats presenting with haemodynamic hyper-reactivity. Methods. The MACbar of sevoflurane was measured in controlsand in animals treated with sufentanil 0.005 µg kg^–1min^–1 before and after administration of i.v. (0.25, 0.5mg kg^–1) and intrathecal (i.t.) (250 µg) ketamine,i.v. (0.5, 1 mg kg^–1) and i.t. (30 µg) MK-801(NMDAantagonist), i.v. (0.1, 0.5 mg kg^–1) naloxone, i.v. (10mg kg^–1) and i.t. (50, 100 µg) ketorolac or i.t.(100, 150 µg) meloxicam (COX-2 inhibitor). Results. Sufentanil 0.005 µg kg^–1 min^–1 significantlyincreased MACbar (3.2 (SD 0.3) versus 1.9 (0.3) vol%). Withthe exception of naloxone, all drugs displayed a significantMACbar-sparing effect (>50%) in controls. Naloxone completelyprevented haemodynamic hyperactivity. Two patterns of reactionwere recorded for the other drugs: either hyper-reactivity wassuppressed and the MACbar-sparing effect was maintained (i.t.ketamine, i.t. MK-801, i.t. ketorolac [100 µg], i.t. meloxicam[150 µg]) or hyper-reactivity was blocked but MACbar-sparingeffect was lost (i.v. ketamine [0.5 mg kg^–1], i.v. MK-801[0.5, 1 mg kg^–1], i.v. ketorolac [10 µg kg^–1],i.t. ketorolac [50 µg], i.t. meloxicam [100 µg]). Conclusions. We have demonstrated that low-dose sufentanil-inducedhaemodynamic hyper-reactivity is an excitatory µ-opiate-relatedphenomenon. This effect is reversed by drugs effective in treatingopiate-induced hyperalgesia.     

Remifentanil-propofol vs. sufentanil-propofol: optimal combinations in clinical anesthesia

BACKGROUND: Two opioid regimens, computer-simulated to provide optimal general anesthesia in combination with propofol, were compared using clinical criteria. METHODS: Fifty patients undergoing thyroid surgery were blindly, prospectively and randomly allocated to receive either (a) i.v. remifentanil (1.5 micro g kg-1, followed by 0.2 micro g kg-1 min-1) or (b) i.v. sufentanil (0.2 micro g kg-1 followed by 0.2 micro g kg-1 h-1). Remifentanil infusion was stopped at the last skin suture. Sufentanil infusion was stopped 30 min before the end of surgery. Intravenous propofol was titrated to keep BIS at 50+/-5. Remifentanil and sufentanil groups were compared with regards to (a) propofol delivery, (b) hemodynamic and recovery variables, and (c) effect-site propofol levels during a steady-state period for effect-site remifentanil and sufentanil levels. P<0.05 was significant. RESULTS: Groups were similar in demographic data; types and durations of surgery; total propofol consumption; and response, extubation and emergence times. During the steady-state period for the opioid delivery, the remifentanil and sufentanil effect-site levels were 5.3 ng ml-1 and 0.18 ng ml-1, respectively (potency ratio=30). In both opioid groups, in accordance with previous computer-simulations, the effect-site propofol concentrations remained (a) within a narrow range unaffected by surgical stimuli, (b) significantly smaller in the remifentanil group than in the sufentanil group, but (c) smaller than expected from previous computer-simulations. More patients required ephedrine following induction of anesthesia in the remifentanil compared with the sufentanil group. CONCLUSIONS: The present clinical trial conducted in thyroid surgery is consistent with previous computer-simulated opioid-propofol combinations with respect to intraoperative and recovery variables. Effect-site propofol ranges were, however, lower than expected.     

Intrathecal sufentanil and morphine for post-thoracotomy pain relief

In this double-blind randomized study we compared a group of15 patients undergoing thoracotomy who received a spinal injectionof sufentanil 20 µg combined with morphine (200 µg)after induction of general anaesthesia with a control groupof the same size. Post-operative pain was rated on a visualanalogue scale (VAS) and a verbal rating scale at rest and witha VAS on coughing. In the recovery room, patients received titratedi.v. morphine until the VAS score was <30, and were followedby patient-controlled analgesia (PCA) for 72 h. The intrathecalsufentanil and morphine group had a lower intra-operative requirementfor i.v. sufentanil and needed less i.v. morphine for titrationin the recovery room. I.v. PCA morphine consumption and painscores were lower in the active group than in the control groupduring the first 24 h. There were no differences afterthis time. Spirometric data (peak expiratory flow, forced vitalcapacity and forced expiratory volume in 1 s) were similarin the two groups. We conclude that the combination of intrathecalsufentanil and morphine produces analgesia of rapid onset andwith a duration of 24 h. Br J Anaesth 2001; 86: 236–40.     

舒芬太尼复合异丙酚抑制气管插管应激反应的效果

【目的】比较靶控输注不同剂量舒芬太尼复合异丙酚抑制气管插管应激反应的效果。【方法】60例择期上腹部手术患者，ASAⅠ～Ⅱ级，随机分为3组m=20），全麻诱导时，A组、B组、C组分别靶控输注效应室浓度为0．3、0．5、0．7ng／mL的舒芬太尼2min后．均输注效应室靶浓度为4μg／mL的异丙酚，病人意识消失后给予维库溴铵行气管插管。记录全麻诱导前1min（T1）、气管插管后1min（T2）、3min（T3、10min（T4）各时点平均动脉压（MAP）、心率（HR）；并于T1、T2、T4时点采集桡动脉血，测定血浆肾上腺素（AD）和去甲肾上腺素（NA）浓度。【结果】（1）A组T2时点MAP、HR比T。时点明显升高（P〈0．0S），C组T2、T3、T4时点MAP明显低于A组（P〈0．05），C组T2、T3时点HR明显低于A组（P〈0．05），C组L、T4时点MAP低于B组（P〈0．05）；（2）A组T2时点血浆AD和NA浓度较T1时点明显升高（P〈0．05）、较B组高（P〈0．05）、较C组高（P〈0．05）。【结论】靶控输注舒芬太尼复合异丙酚可以有效抑制气管插管应激反应，其中舒芬太尼效应室浓度0．5ng／mL复合异丙酚效应室浓度4μg／mL靶控输注的效果较好。     

小剂量芬太尼、瑞芬太尼和舒芬太尼预防儿童经口气管插管心血管反应的比较

目的比较小剂量芬太尼、瑞芬太尼和舒芬太尼对患儿直接喉镜经口气管插管心血管反应的影响。方法选择120例施择期整形外科手术的患儿。随机平均分成对照组、芬太尼组、瑞芬太尼和舒芬太尼组,气管插管前采用盲法分别应用9g/L盐水0.2mL/kg、芬太尼2μg/kg、瑞芬太尼组1μg/kg和舒芬太尼0.2μg/kg。静脉麻醉诱导后采用直接喉镜实施经口气管插管。监测麻醉诱导前、后,气管插管时和气管插管后5min内血压(BP)和心率(HR)及观察期收缩压(SBP)和HR的变化率,并记录观察期SBP和HR达最大值时间及其气管插管后恢复至麻醉诱导后值时间。结果BP和HR基础值及气管插管时间在4组间均无显著性差异。气管插管致BP和HR较基础值显著升高,且是以对照组最为明显,芬太尼组次之,瑞芬太尼和舒芬太尼组最轻。对照组气管插管时BP和HR及其观察期最大值均显著高于芬太尼组、瑞芬太尼和舒芬太尼组;瑞芬太尼组和舒芬太尼组气管插管时的血压和HR及其观察期最大值均显著低于芬太尼组(Pa<0.05)。瑞芬太尼组观察期出现SBP和HR最大值时间显著长于对照组、芬太尼组和舒芬太尼组(Pa<0.05);舒芬太尼和瑞芬太尼组气管插管后SBP和HR恢复至麻醉诱导后值时间显著短于对照和芬太尼组(P<0.05)。瑞芬太尼和舒芬太尼组观察期SBP和HR增加大于基础值30%发生率较芬太尼组显著降低。结论与小剂量芬太尼比较,小剂量舒芬太尼和瑞芬太尼能更有效预防患儿经口气管插管的心血管反应。     

Effect of sufentanil on intracranial pressure in neurosurgical patients

The effects of sufentanil on intracranial pressure, mean arterial pressure, cerebral perfusion pressure and heart rate were studied in 20 neurosurgical intensive care unit patients. Epidural intracranial pressure probes were implanted in patients who suffered head injury, intracerebral haemorrhage or underwent tumour resection. Sufentanil was given intravenously in sequential doses of 0.5, 1.0 and 2.0 micrograms/kg. Fifteen minutes elapsed after each dose. The patients were allocated to either group 1 (baseline intracranial pressure less than 20 mmHg) or group 2 (baseline intracranial pressure greater than 20 mmHg). Intracranial pressure did not change significantly in either group. Therefore the falls in mean arterial pressure with the highest dose in both groups and with 1.0 micrograms/kg in group 2, closely reflect corresponding reductions in cerebral perfusion pressure. As sufentanil in itself exerts no effects on intracranial pressure, concomitant haemodynamic changes are the critical factor for an adequate cerebral perfusion pressure.     

小剂量布比卡因混合舒芬太尼腰麻对TURP老年患者心输出量的影响

【目的】探讨布比卡因混合舒芬太尼腰麻对前列腺电切术（transurethral resection of the prostate,TURP）老年患者心输出量的影响。【方法】60例ASAⅠ-Ⅲ级择期行TURP 60岁以上患者随机分为A,B,C组,每组20例。A组：布比卡因15 mg＋10%葡萄糖溶液,B组：布比卡因7.5mg＋舒芬太尼5μg＋10%葡萄糖溶液;C组：布比卡因7.5 mg＋舒芬太尼7.5μg＋10%葡萄糖溶液;三者的容量均为3mL。通过阻抗心动描记法血流动力学监测仪（BioZ.com）分别于注药前1 min（T0）、注药后3 min（T1）、10 min（T2）3、0 min（T3）4个时点监测血流动力学,读取参数：心输出量（CO）、心率（HR）、心指数（CI）外周血管阻力指数（SVRI）。【结果】A组的CO,CI,SVRI在腰麻后10 min和30 min明显减少。B组和C组腰麻后3、10、30 min的CO,CI,SVRI明显高于A组（P〈0.01）,C组与B组比较,在腰麻后10 min的CO,CI相比较也有统计学意义（P〈0.05）。【结论】小剂量布比卡因复合舒芬太尼腰麻对TURP老年患者血液动力学影响小,麻醉能增加外周阻力,心输出量增加,能避免腰麻对老年患者产生低血压的不良影响。     

舒芬太尼麻醉在老年患者全麻诱导期对血流动力学的影响

目的：研究舒芬太尼在老年患者全麻诱导中对血流动力学的影响。方法：选择拟行全身麻醉的老年患者40例，随机分为两组，每组20例，实验组诱导时用舒芬太尼，对照组用芬太尼，分别记录麻醉前、诱导后2min、插管时、插管后1，3，5和10min各时点的平均动脉压、心率、心输出量、心脏指数、每搏输出量、外周血管阻力、心肌加速度指数。结果：实验组平均动脉压、心率在插管时和插管后1min明显低于对照组（P〈0．05）。观察期间实验组心输出量、心脏指数均无明显变化（P〉0．05），而对照组在诱导后、插管时和插管后心输出量、心脏指数明显低于诱导前（P〈0．05）。结论：与芬太尼相比，舒芬太尼在老年患者全麻诱导过程中平均动脉压、心输出量、心脏指数、心率等血流动力学指标影响较少，能更好地保持循环系统的稳定。     

Efficacy and Tolerability of Sufentanil,Dexmedetomidine, or Ketamine Added to Propofol-based Sedation for Gastrointestinal Endoscopy in Elderly Patients: A Prospective,Randomized, Controlled Trial

PurposeTo investigate the optimal agent combined with propofol for sedation in elderly patients undergoing gastrointestinal endoscopy.MethodsA total of 120 elderly patients scheduled for gastrointestinal endoscopy under propofol-based sedation were randomly allocated to receive propofol + saline (control group), propofol + sufentanil 0.1 μg/kg, propofol + dexmedetomidine 0.4 μg/kg, or propofol + ketamine 0.4 mg/kg. Mean arterial pressure, heart rate, pulse oximetry, pressure of end-tidal carbon dioxide, respiratory rate, and Ramsay sedation scale score were recorded. Induction time, procedure time, recovery time, propofol dose, and adverse events were also recorded.FindingsDuring the sedation procedure, the AUC of HR was lowest in the propofol + dexmedetomidine group (all, P < 0.05), and the AUC of pulse oximetry was significantly higher in the propofol + dexmedetomidine and propofol + ketamine groups compared to the other 2 groups (both, P < 0.05). The propofol + dexmedetomidine group had the highest prevalences of hypotension and bradycardia, and the control group experienced the largest number of hypoxia episodes (all, P < 0.05). The control group consumed the highest dose of propofol, while the propofol + ketamine group needed the lowest dose (all, P < 0.05).ImplicationsThe combination of propofol + ketamine 0.4 mg/kg maintained hemodynamic and respiratory stability, as evidenced by less hypotension, bradycardia, and hypoxia events, in elderly patients undergoing gastrointestinal endoscopy. China clinical trial registration (chictr.org.cn) ID: ChiCTR-INR-17013710.