Haemodynamic and electroencephalograph responses to intubation during induction with propofol or propofol/fentanyl

Purpose

To observe the changes in EEG bispectral index (BIS), 95% spectral edge frequency (95% SEF) and median frequency (MF) with haemodynamic changes to intubation during induction with propofol or propofol and 2 μg· kg^?1 fentanyliv.

Methods

Twenty four ASA 1–11 patients were randomized to receive either propofol infusion preceded by normal saline (group P, n= 12) or propofol preceded by 2 μg· kg^?1 fentanyl (group PF, n= 12). Intubation was performed five minutes after maintenance of BIS within 45 ± 5. EEG and haemodynamic variables were recorded at before induction, and before and after intubation.

Results

Haemodynamic responses to intubation were greater in group P than in group PF (P < 0.05). Postintubation SBP, DBP and HR increased, compared with preinduction values, more in group P than in group PF Postintubation BIS values increased from 45.5 ± 3.5 and 44.2 ± 4.1 to 51.1 ± 4.1 and 50.9 ± 5.3 in groups P and PF, respectively, compared with preintubation values. The BIS values were not different between treatment groups before and after intubation, and 95% SEF and MF values did not increase after intubation.

Conclusion

Fentanyl, 2 μg· kg^?1 iv, blunted the haemodynamic responses to intubation, but failed to attenuate the arousal of cerebral cortical activity. The different haemodynamic responses postintubation but similar BIS and 95% SEF changes in the two groups suggest that BIS or 95% SEF cannot predict the haemodynamic responses to intubation during anaesthesia induction with propofol and fentanyl.     

Effects of fentanyl or alfentanil as supplement to propofol anaesthesia for termination of pregnancy

One hundred and twenty patients undergoing early legal termination of pregnancy by dilatation and suction curettage before 12 weeks of pregnancy were randomly allocated to receive total intravenous propofol anaesthesia either alone or supplemented with fentanyl 1.5 μg·kg^-1 or alfentanil 15 μg kg^-1. Supplementation with fentanyl or alfentanil improved operating conditions ( P <0.01), reduced total propofol requirements ( P < 0.01) and reduced postoperative pain intensity ( P < 0.05). Immediate recovery, assessed by the time patients took to open the eyes, to give correct date of birth and by co–operation score, was more rapid in the alfentanil group compared to the control group ( P < 0.05), whereas there was no significant difference between the alfentanil and fentanyl groups. The three anaesthetic techniques did not differ with regard to side effects.
In conclusion, total intravenous propofol anaesthesia in patients undergoing early termination of pregnancy was improved by supplementation with either fentanyl 1.5 μg kg^-1 or alfentanil 15 μg–kg^-1. The benefit was slightly greater with alfentanil than with fentanyl.     

靶控输注舒芬太尼及芬太尼对丙泊酚药效学的影响

目的探讨靶控输注（TCI）舒芬太尼及芬太尼对丙泊酚药效学的影响.方法30例择期全麻下行妇科腹腔镜手术患者,随机均分为两组：与丙泊酚复合应用的舒芬太尼TCI为0.5 ng/ml（SF组）;芬太尼为2.5 ng/ml（F组）.观察麻醉期血液动力学改变、泵注丙泊酚的入睡时间、BIS降至60的时间、停药后患者的拔管时间、睁眼时间、定向力恢复时间、OAA/S评分及术后24 h并发症.结果（1）F组麻醉诱导时的SBP、DBP低于SF组（P＜0.05）;两组在麻醉诱导时HR比麻醉前均显著降低（P＜0.05）;F组在手术开始时的SBP、DBP、MAP高于SF组（P＜0.05）;F组拔管期的SBP、DBP均高于SF组（P＜0.05）;（2）SF组的入睡时间明显短于F组（P＜0.05）;停止丙泊酚后30、60 min SF组的OAA/S评分低于F组（P＜0.05）;（3）SF组术后24 h躁动发生率、主诉需要阿片类药物少于F组（P＜0.05）.结论舒芬太尼丙泊酚TCI入睡快,围术期血液动力学更加平稳.     

Anaphylactoid reaction to propofol

A case of an anaphylactoid reaction following the induction of anaesthesia is reported. Subsequent intradermal testing suggested propofol to be the causative agent.     

丙泊酚复合咪唑安定和/或芬太尼在胆道镜操作过程中的镇静作用

目的研究丙泊酚复合咪唑安定和/或芬太尼用于胆道镜操作过程中的镇静效果。方法选择18~65岁行胆道镜的患者90例,随机分为三组:PF组(n=31),首次静注芬太尼0.05 mg+丙泊酚1 mg/kg;PM组(n=29),首次静注咪唑安定2 mg+丙泊酚1 mg/kg;PMF组(n=30),首次静注芬太尼0.05 mg+咪唑安定2 mg+丙泊酚1 mg/kg。各组根据需要追加丙泊酚每次20~30 mg。记录心率、血压、脉搏血氧饱和度、镇静分级,观察患者症状及记忆缺失情况。结果用药后1 min三组患者都能达到满意的镇静效果(镇静分级2~3级);所有患者停药后17 min完全清醒,PF组恢复时间最短(P<0.01),但有21例(67.7%)对操作过程有记忆,只有15例(48.4%)患者对麻醉镇静的方法感到很满意。结论丙泊酚复合咪唑安定和/或芬太尼在胆道镜操作中镇静效果更好,无明显不良反应。     

The use of propofol in combination with fentanyl or buprenorphine in long-duration anesthesia

Fifty patients of both sexes, aged between 37 and 60 years old and belonging to ASA classes I, II, III and IV, underwent urological surgery lasting more than two hours under general anesthesia using a continuous infusion of propofol, N2O/O2, vecuronium bromide 0.02% infusion. Patients were divided into two groups of 25, group A and group B, according to whether they received fentanyl or buprenorphine as an analgesic. Propofol and fentanyl consumption in group A were 5.43 +/- 0.7 mg/kg/hour and 10.53 +/- 1.7 micrograms/kg respectively, whereas those of propofol and buprenorphine in group B were 5.71 +/- 1.08 mg/kg/hour and 6.05 +/- 0.06 micrograms/kg; there was a statistically non-significant difference for propofol consumption (p greater than 0.005). During the induction and maintenance phases of anesthesia, hemodynamic parameters decreased significantly (p less than 0.001) in comparison to starting values in both groups, but no statistically significant differences were observed. Buprenorphine prolonged reawakening from anesthesia by a few minutes but at the same time extended postoperative analgesia by several hours, thus improving the overall quality of the immediate postoperative period. The most frequent side effect (32% in group A and 52% in group B) was sinusal bradycardia.     

The relationship of individual sensitivities to fentanyl and those to propofol

BACKGROUND: Individual variation in the sensitivity to anesthetics induces the delayed awakening and the severe postoperative pain at an inappropriate dose. We designed the study to see the correlation of the individual sensitivity to fentanyl and that to propofol which have different mechanism. METHODS: General anesthesia was induced using target controlled infusion system of fentanyl and propofol. Fentanyl effect-site concentration gradually increased towards a target plasma concentration of 3 ng x ml(-1) until the appearance of the subjective symptom such as dizziness, a sensation of warmth and other reactions. After this, propofol effect-site concentration gradually increased towards a target plasma concentration of 4 microg x ml(-1) until loss of consciousness (LOC). The effect-site concentrations of fentanyl at the symptom and propofol at loss of consciousness were measured. RESULTS: The correlation between the estimated effect-site concentration of fentanyl and propofol is not significant in the whole patient. However, a positive correlation between fentanyl and propofol was found in patients from 50s to 70s years of ages (r = 0.59). CONCLUSIONS: The correlation of the individual sensitivity to fentanyl and propofol was found in older age groups.     

An anaphylactic reaction to transdermal delivered fentanyl

Immediate allergic hypersensitivity reactions with fentanyl are rarely reported. We diagnosed a presumably IgE-mediated allergic hypersensitivity reaction comprising generalized erythema and bronchospasm 4 h after the first-time application of transdermal fentanyl. Prick test remained negative with fentanyl whereas an intradermal test (IDT) with fentanyl was positive (dilution 10⁻²). Cross-reactivity was found with sufentanil but not with remifentanil. The diagnosis was supported by the clinical history and a positive IDT with fentanyl. This case report confirms the need for a systematic allergological investigation in case of immediate hypersensitivity reactions for all drugs and all modes of administration.     

Comparison of the effects of fentanyl on respiratory mechanics under propofol or thiopental anaesthesia

Twenty patients were randomly anaesthetized with either thiopental 5 mg/kg followed by a 15 mg/kg/h continuous infusion, or propofol 2.5 mg/kg followed by a 9 mg/kg/h continuous infusion, paralysed with vecuronium 0.1 mg/kg, intubated and ventilated with nitrous oxide 50% in oxygen. Fifteen minutes after induction, fentanyl 5 micrograms/kg was injected. Inspiratory tracheal pressure (PT), gas flow (V) and volume (V) were continuously measured while the lungs were inflated with a constant inspiratory flow ventilator. Respiratory compliance (Crs) and resistance (Rrs) were calculated from the regression of PT on V. In both groups Crs decreased following anaesthesia. Fentanyl injection elicited an increase in Rrs (from 1.04 +/- 0.70 to 1.63 +/- 0.92 kPa x l-1 x s) and a further decrease in Crs (from 0.55 +/- 0.30 to 0.42 +/- 0.10 l x kPa-1) in the thiopental group but not in the propofol group (Rrs: 1.26 +/- 0.69 to 1.08 +/- 0.44 kPa x l-1 x s, Crs: 0.49 +/- 0.11 to 0.48 +/- 0.13 l x kPa-1). These results suggest that the dose of propofol administered in this study may prevent fentanyl-induced bronchoconstriction.     

咪唑安定或丙泊酚伍用芬太尼对镇静深度和呼吸、循环的影响

目的　观察咪唑安定或丙泊酚伍用芬太尼对镇静和呼吸、循环的影响,探讨脑电双频 指数(BIS)与呼吸、循环参数的关系。方法　选择行四肢或下腹部手术患者40例,随机均分为四组: 丙泊酚组(P组)、丙泊酚加芬太尼组(PF组)、咪唑安定组(M组)和咪唑安定加芬太尼组(MF组)。 静注芬太尼0.05mg(1ml)或生理盐水1ml(观察者不知);丙泊酚负荷量1mg/kg,维持量0.05mg ·kg 1·min 1;咪唑安定负荷量0.1mg/kg,维持量0.01mg·kg 1·min 1。观察并每隔2分钟记录 患者呼吸指标(PETCO2、PaO2、PaCO2、SaO2等)及循环指标,并与BIS、95%边缘频率(95%SEF)和警 觉/镇静观察评分(OAA/S)进行相关分析。结果　观察期间各组无因循环指标达到“黄牌”而停药, 均因呼吸指标达到“黄牌”而停止给药。BIS与用药剂量呈负相关,与OAA/S和95%SEF呈正相关, BIS与PaCO2、PETCO2和RR呈负相关,与VT、VE、SpO2、SaO2呈正相关,PF组HR比P组慢(P< 0.01)。MF组的PETCO2、RR及HR与M组有明显变化(P<0.01)。结论　本研究条件下最合适 的镇静水平维持OAA/S评分2～3分、BIS72～80为宜,此时呼吸、血液动力学稳定,对手术刺激无 反应且能产生遗忘,同时对呼吸、循环抑制较轻。