碱化丁卡因溶液尿道粘膜表面麻醉的临床观察和药代动力…

１６例接受膀胱镜检的患者分为临床碱化对照组；将２０只家兔匀分为动物碱化组和动物对照组。碱化组均给予ｐＨ７．１５的１％丁卡因溶液，对照组给予ｐＨ５．１的１％的丁卡因溶液。结果，临床碱化组麻醉效果优于临床对照组。但临床对照组药液在务耱中达峰时间快；峰浓度及血药浓度的各个时点均高于临床碱化组。     

硬膜外阻滞加气管内全麻与单纯气管内全麻用于全胃切除术的对比研究

硬膜外阻滞加气管内全麻（硬气组）和单纯气管内全麻（对照组）用于全胃切除术，对患者血流动力学、血浆儿茶酚胺、皮质醇浓度及动脉血气的变化进行了对比观察，以其探索对应激反应的影响。结果表明硬气组插管后及术中ＭＡＰ、ＨＲ波动小，与对照组有显著性差异（Ｐ＜０．０１）。硬气组气管插管后５分钟血浆儿茶酚胺总量和去甲肾上腺素浓度与麻醉前相比有所降低，对照组却显著升高（Ｐ＜０．０５）。两组之间比较有显著性差异（Ｐ＜０．０５）。儿茶酚胺浓度降低与ＭＡＰ有显著相关性。术中两组血浆皮质醇浓度均略升高，显示了硬气组不影响皮质醇的正常分泌。两组动脉ｐＨ、ＢＥ术毕与麻醉前相比均降低（Ｐ＜０．０５），但对照组降低更显著（Ｐ＜０．０５）。     

利多卡因pH及PCO2对硬膜外麻醉效果的影响

３０例下胸段硬膜外麻醉病人随机分为三组，均用１．３３％利多卡因，其ｐＨ和ＰＣＯ２分别为，Ａ组ｐＨ４．７～４．８，ＰＣＯ２０．４～０．５ｋＰａ；Ｂ组ｐＨ７；２～７．４，ＰＣＯ２５３．３～５４．７ｋＰａ；Ｃ组ｐＨ７．２～７．４，ＰＣＯ２８．Ｏ～１０．０ｋＰａ。结果：各组麻醉起效时间无显著差异；各组麻醉持续时间为，Ａ组６５．７±３０．３ｍｉｎ，Ｂ组５１．２±３２．７ｍｉｎ，Ｃ组３１．７±１６．７ｍｉｎ（与Ａ组比，Ｐ＜０．０５）。另外，Ａ组肌松率明显高于Ｃ组，Ｐ＜０．０５。结论：单纯提高利多卡因ｐＨ（Ｃ组），则缩短硬膜外麻醉持续时间，肌松差；碱化利多卡因中的高ＰＣＯ２（Ｂ组）在一定程度上可弥补高ｐＨ的作用。     

糖尿病患者肾血流与内皮素及降钙素基因相关肽关系

目的为了解内皮素（ＥＴ）及降钙素基因相关肽（ＣＧＲＰ）与糖尿患者不同阶段时肾血流的关系。方法肾彩色多普勒超声检查确定为糖尿病肾血流正常组（Ａ组）１５例、糖尿病肾血流减少组（Ｂ组）１５例，正常对照组１８例。分别采血测定血浆ＥＴ－１和ＣＧＲＰ浓度。结果Ａ组ＥＴ－１水平低于正常对照组（Ｐ＜０．０１），Ｂ组ＥＴ－１水平高于正常对照组（Ｐ＜０．０１）。二组ＥＴ－１水平与肾动脉收缩期峰值血流速度（Ｖｍａｘ）、肾动脉血流量（Ｑ）呈负相关（Ｐ＜０．０１），与尿白蛋白排泄率（ＵＡＥＲ）呈正相关（Ｐ＜０．０５）。二组的ＣＧＲＰ水平均低于正常组（Ｐ均＜０．０１），但Ａ与Ｂ组的ＣＧＲＰ水平差异无显著性（Ｐ＞０．０５）。未发现ＣＧＲＰ水平与Ｖｍａｘ、Ｑ和ＵＡＥＲ呈相关关系。结论ＥＴ－１在糖尿病不同阶段时对肾血流量的病理生理作用可能不同；糖尿病患者呈现低ＣＧＲＰ血症，但它对不同阶段的糖尿病肾血流的影响尚有待探讨。     

呼吸气体监测仪对紧闭麻醉环路内氧浓度的影响

３４例腹部手术患者采用紧闭吸入麻醉，术中持续监测吸入氧浓度和脉搏血氧饱和度（ＳｐＯ２），随机分两组，Ⅰ组为对照组，Ⅱ组加用Ｃａｐｎｏｍａｃ　Ｕｌｔｉｍ。呼吸气体监测仪持续监测。结果显示。Ｉ组吸人氧浓度于紧闭１小时下降约１０％（与麻醉初比较，Ｐ＜０．０１），随后基本保持平稳。Ⅱ组氧浓度１小时下降１６％，至３小时约下降３５％（与Ⅰ组比较，Ｐ均小于０．０１），文章还探讨了吸入氧浓度下降的原因。     

碱化利多卡因硬膜外阻滞行剖宫产时母婴血药浓度测定及药效学研究

选择剖宫产产妇１８例，随机分成两组，每组９例。硬膜外穿刺置管后分别注入碱化（ＰＨ７．３０）与非碱化（ＰＨ４．９７）的１．６％利多卡因。对比观察两组药效学及给药后２～５２分钟的血药浓度及Ｃｍａｘ、Ｔｍａｘ，新生儿娩出时母体及新生儿的血药浓度，新生儿娩出后Ａｐｇａｒ评分。结果显示，碱化组起效时间、阻滞完善时间均比对照组缩短，给药后２～２２分钟血药浓度均显著高于对照组。碱化组Ｃｍａｘ（３．２５±０．６９ｍｇ／Ｌ）高于对照组（２，５８±０．７３ｍｇ／Ｌ）（Ｐ＜０．０５）。碱化组Ｔｍａｘ（１７．５６±３．００分钟）较对照组（２７．００±６．１２分钟）短（Ｐ＜０．０１）。分娩即刻新生儿及母体的血药浓度显著高于对照组。两组新生儿娩出后１分钟和５分钟的ＡＰｇａｒ评分差异无显著意义。结论是碱化利多卡因比非碱化利多卡因血药浓度增高，有可能使其毒性增加，在产科手术中应慎用。     

腹腔镜胆囊切除术中肺功能变化的临床研究

本文观察了１２例ＡＳＡ１级胆囊结石病人腹腔镜胆囊切除术中的肺功能变化。年龄为４０．７±９．４岁，体重６１．４±９．４ｋｇ。Ｍｉｄａｚｏｌａｍ－Ｆｅｎｔａｎｙｌ－Ｉｓｏｆｌｕｒａｎｅ－Ｔｒａｃｒｉｕｍ维持麻醉，控制呼吸，间歇正压通气。连续监测吸气气道峰压（ＰＩＰ），动态肺应性（ＬＣ），ＰＥＣＯ２，ＥＫＧ，ＮＩＢＰ和ＳｐＯ２。结果：体位改变对ＰＩＰ和ＰＥＣＯ２无明显影响（Ｐ＞０．０５），却使ＬＣ下降９．７％（Ｐ＞０．０５）。腹腔充气后３０分钟ＰＩＰ上升１７％（Ｐ＜０．０５），ＬＣ与麻醉后和充气前相比分别下降２５．８％和２０．８％（Ｐ＜０．０１），ＰＥＣＯ２增加１９．１％（Ｐ＜０．０１）；腹腔充气后６０分钟，ＰＩＰ和ＰＥＣＯ２未继续增加，但ＬＣ继续下降，比麻醉后和充气前下降３４．２％和２７．１％（Ｐ＜０．０１）。本文显示腹腔镜胆囊切除术中肺顺应性显著下降，气道压明显升高，ＰＥＣＯ２明显增加。     

利多卡因溶液碱化对其LD50的影响

为了解局麻药碱化后其毒性是否改变，选用Ｓｐｒａｇｕｅ－Ｄａｗｌｅｙ小鼠为研究对象，采用ＮａＨ－ＣＯ３和ＮａＯＨ为碱化剂，对利多卡因溶液进行了碱化。并对不同ｐＨ药液的ＬＤ５０进行了计算和分析。实验结果显示：（１）以ＮａＨＣＯ３和ＮａＯＨ为碱化剂时，前者碱化的药液可出现沉淀现象；（２）当以ＮａＯＨ为碱化剂时，药液ｐＨ在４．５～７．０时其ＬＤ５０显著升高（Ｐ＜０．０５）；（３）当以ＮａＨＣＯ３为碱化剂时，不同ｐＨ药液的ＬＤ５０的变化无显著性。     

咪唑安定—异氟醚静吸复合麻醉用于颅脑手术的临床效果观察

报告咪唑安定－异氟醚静吸复合麻醉用于颅脑手术的临床效果观察。２２例择期开颅手术患者被随机分成咪唑安定－异氟醚组（Ｉ组）及单纯异氟醚组（Ⅱ组）。对比观察两组在手术不同时期的血流动力学及异氟醚吸入浓度的变化。结果显示两组血压均未见增高，且明显低于基础值（Ｐ＜０．０５），Ｉ组异氟醚吸入浓度明显低于Ⅱ组，降低 ２７％左右（Ｐ＜０．０１）。本研究结果提示，咪唑安定 ０．２ｍｇ· ｋｇ－１／ｈ持续静滴维持麻醉可降低异氟醚ＭＡＣ，对血流动力学影响轻微，术中麻醉平稳，适用于神经外科手术麻醉。     

海洛因依赖者的精液分析研究

对３０名男性海洛因依赖者（下称吸毒组）进行吸毒史调查,并进行精液常规分析及生化分析,与３０名正常男性精液作对照。结果表明,与对照组相比吸毒组精液量减少（Ｐ＜０．０５）,精子计数减少（Ｐ＜０．０１）,精子活力减低（Ｐ＜０．０１）,活动率降低（Ｐ＜０．０１）,且精子活力与吸毒总量、精子计数与吸毒总量均呈负相关关系（ｒ１＝－０．８３,ｒ２＝－０．６３）。吸毒组精浆果糖浓度降低（Ｐ＜０．０１）。精浆锌、钙浓度低下（Ｐ＜０．０５）,而精浆铁浓度明显升高（Ｐ＜０．０１）。精液涂片观察发现吸毒组精子畸形率明显高于对照组。结果表明海洛因依赖可导致男性精液质与量发生明显异常改变。     

A comparison of Rapydan® patch and Ametop® gel for venous cannulation

Ametop^® gel (4% tetracaine) is used to provide topical anaesthesia for venous cannulation. Rapydan^® patch (7% lidocaine and 7% tetracaine) has been developed to provide topical anaesthesia by a different mechanism, that of heat assisted delivery. We compared the topical anaesthetic effect of these agents for venous cannulation. One hundred healthy adults undergoing day‐case surgery were randomly assigned to receive either Rapydan (n = 50) or Ametop (n = 50) before venous cannulation. Pain on insertion was scored on a visual analogue scale between 0 and 100 (where 100 = unbearable pain). Median(IQR[range]) pain scores were not different between groups with 11 (5–20 [0–72]) for Rapydan and 10 (5–24 [0–95]) for Ametop (p = 0.63). Adequate topical anaesthesia was achieved in over 90% of patients in both groups. Rapydan produces topical anaesthesia comparable with Ametop for venous cannulation.     

Comparison of hyperbaric solutions of bupivacaine and tetracaine during continuous spinal anaesthesia

The aim of this study was to compare two equipotent solutions of hyperbaric bupivacaine and tetracaine in 30 elderly patients undergoing elective hip surgery under continuous spinal anaesthesia. With the patient in the supine position, 2 ml (8 mg) of either hyperbaric solution (density 1.030) were administered in a double-blind and randomized fashion. The median maximum sensory and temperature discrimination levels (T5 and T4) were similar with both solutions. The duration of analgesia was not different (114 +/- 23 min for bupivacaine and 125 +/- 35 min for tetracaine). Thirteen out of fifteen patients receiving bupivacaine and all 15 patients receiving tetracaine had complete motor blockade. The haemodynamic changes and vasopressor requirements were comparable. The plasma catecholamine levels measured at four different times remained unchanged and were not different between the two groups at any time. The authors conclude that, during continuous spinal anaesthesia, equipotent hyperbaric solutions of bupivacaine and tetracaine have similar anaesthetic and haemodynamic effects.     

The clinical use of small-dose tetracaine spinal anesthesia for transurethral prostatectomy

In a double-blinded study, we compared conventional dose tetracaine (8 mg), small-dose tetracaine (4 mg) with added fentanyl and epinephrine, and small-dose tetracaine (4 mg) with added fentanyl subarachnoid anesthesia. Forty-five patients scheduled for transurethral resection of prostate (TURP) under subarachnoid anesthesia were randomly assigned to Group 1 (8 mg hyperbaric tetracaine), Group 2 (4 mg hyperbaric tetracaine, 10 microg fen-tanyl, and 0.2 mg epinephrine), and Group 3 (4 mg hyperbaric tetracaine, 10 microg fentanyl, and 0.2 mL saline). Evaluations were performed after spinal anesthesia. Subarachnoid block was successful in all patients except one in Group 1, who required general anesthesia by mask. The median peak sensory levels 10 min after the induction of spinal anesthesia in Group 1 was T8, which was significantly higher than Group 2 and Group 3 (P < 0.05). The time of sensory and motor recovery in Group 3 was less than in Groups 1 and 2 (P < 0.05). Hypotension was observed in four patients in Group 1 and none in Groups 2 and 3. We conclude that small-dose 4-mg hyperbaric tetracaine plus 10 microg fentanyl might provide adequate anesthesia and fewer side effects for TURP when compared with the conventional (8 mg) dose. IMPLICATIONS: Small-dose hyperbaric tetracaine (4 mg with 10 microg fentanyl added) may provide adequate anesthesia and fewer side effects for transurethral resection of the prostate.     

Effects of different glucose concentrations on spinal anaesthesia with bupivacaine and tetracaine

The effects of 5% and 8% glucose in 0.5% tetracaine or bupivacaine on the anaesthetic spread were investigated in 80 urological patients requiring spinal anaesthesia for trans-urethral resection of the prostate. The local anaesthetic solutions were randomly administered, the patients being divided into four groups of 20, and the anaesthetic profile was then evaluated in a double-blind fashion by an independent observer. Maximum cephalad spread of analgesia was significantly greater with tetracaine in 8% glucose compared to the other three groups (tetracaine/5% glucose, bupivacaine/5 or 8% glucose) (P less than 0.05). Glucose concentration significantly influenced spreading characteristics of tetracaine, the 8% solution achieving a higher level in a shorter time than the 5% solution. Sensory regression to both T10 and S1 dermatome was longer with bupivacaine in 8% glucose compared to 5% glucose. The concentration of glucose, however, did not influence the regression of sensory analgesia for tetracaine. Both the 5% and 8% solutions of tetracaine achieved a 3+ motor blockade significantly faster than either bupivacaine solution. Regression of motor blockade from tetracaine was not influenced by the glucose concentration, but the 8% solution of bupivacaine had a delayed 2+ and 3+ blockade, although the ultimate decay for both solutions was similar. The results of our study suggest that 0.5% bupivacaine 4 ml in 5% glucose provides a rapid and controllable spread of sensory analgesia for transurethral surgery, of optimal duration associated with a complete motor blockade of moderate duration.     

Analyse des échecs de la rachianesthésie en fonction de l''évolution de la pratique d''un hôpital universitaire

This study is a retrospective analysis of 303 consecutive spinal anaesthesia performed in orthopaedic patients of a University Hospital between January and December 1990. Failure of spinal anaesthesia was defined as the requirement for general anaesthesia to perform surgery. The parameters studied as possible risk factors of failure were patients demographics, local anaesthetic agents and solutions and techniques of spinal anaesthesia (single injection versus continuous spinal anaesthesia). Failures were related to inadequate or incomplete extension of sensory blockade or to difficulties to perform spinal injection. Continuous spinal anaesthesia was performed in 209 patients mostly with 0.5% isobaric bupivacaine, while 94 patients received a single injection of either hyperbaric 0.5% tetracaine with adrenaline or 0.5% bupivacaine or 5% lidocaine. Failures occurred in 6.3% of the cases but were significantly less frequent with continuous spinal anaesthesia (4.8%) than with the conventional technique (9.6%). The incidence of failure was higher with hyperbaric tetracaine (11.1%) confirming its poor reliability. Inadequate extension of the anaesthetic block was the main cause of failure whatever the spinal anaesthetic technique. These results point out the reliability of continuous spinal anaesthesia but problems may occasionally occur due to spinal catheter misplacement.     

A prospective evaluation of the failure rate of spinal anaesthesia for transurethral prostatic resection.

The rate of failed spinal anaesthesia, defined as the need for unplanned general anaesthesia, was evaluated in a prospective study involving 137 patients undergoing transurethral resection of the prostate (TURP). The incidence of sensations at the operative site which did not require general anaesthesia was also evaluated. Attention to details was emphasized in the technique. Patients randomly received either hyperbaric Niphanoid tetracaine (n = 74; 6 or 10 mg) or hyperbaric bupivacaine (n = 61; 6 mg), with or without adrenaline. General anaesthesia was necessary in one patient (0.72%). Twelve additional patients reported sensations at the operative site which were rapidly relieved by light intravenous supplementation with low doses of fentanyl and/or thiopentone. The patients reporting sensations did not differ in demographic characteristics, spinal technique, local anaesthetic, or degree of sensory or motor blockade. Addition of adrenaline to the 6-mg doses of both tetracaine and bupivacaine decreased the incidence of sensations at the operative site.     

Clonidine prolongs canine tetracaine spinal anaesthesia

Using a randomized blind cross-over design, the comparative efficacy of clonidine in prolonging tetracaine spinal anaesthesia was studied in six mongrel dogs. Lumbar subarachnoid injections (1 ml) of: tetracaine 4 mg with clonidine 150 micrograms, tetracaine 4 mg with epinephrine 200 micrograms, tetracaine 4 mg, clonidine 150 micrograms, epinephrine 200 micrograms, and five per cent dextrose in H2O (vehicle) were administered randomly to each animal at 5-7 day intervals. Subarachnoid tetracaine produced a motor blockade of 186 +/- 58 (mean +/- SEM) min. Both clonidine and epinephrine produced a similar prolongation of tetracaine motor blockade, 135 per cent (p less than 0.01) and 116 per cent (p less than 0.05) respectively, compared with tetracaine alone. No motor blockade was observed in dogs receiving clonidine, epinephrine or five per cent dextrose in H2O. The addition of clonidine to tetracaine spinal anaesthesia produced a significant increase in duration of sensory blockade, 56 per cent (p less than 0.01) and 107 per cent (p less than 0.01) respectively, when compared to tetracaine with and without epinephrine. Subarachnoid clonidine alone produced a sensory blockade of 76 +/- 17 minutes, while only one animal receiving subarachnoid epinephrine had a sensory blockade (40 minutes). No neurologic deficits were observed in any of the animals. The study concludes that during spinal anaesthesia with tetracaine in dogs, clonidine is as effective as epinephrine in prolonging motor blockade, but is more effective in prolonging sensory blockade.     

Comparative topical anaesthesia of EMLA and liposome-encapsulated tetracaine

Background

The eutectic mixture of local anaesthetics (EMLA) provides effective topical anaesthesia after a minimum of 60 to 90 mm application. Since liposome-encapsulated tetracaine (LET) can provide rapid dermal penetration, the goal of this study was to compare the local anaesthetic effects of EMLA and LET in human volunteers after 60 mm application.

Methods

After obtaining institutional approval and informed consent, healthy volunteers were recruited in a double blind, crossover, randomized trial. The study creams (0.5 ml EMLA and 0.5 ml LET 5%) were applied randomly to opposite arms for 60 min. The discomfort of iv cathetenzation was assessed using a visual analogue pain score (VAS). Cutaneous side effects of the creams were recorded.

Results

Sixty-one subjects were studied. Twenty-one were excluded because of technical difficulties. Forty subjects completed the study and were included in the data analysis. The mean (±SD) VAS was lower for LET than for EMLA (10.9 ± 9.0 mm vs 22.7 ± 17.1 mm, P < 0.001). Erythema secondary to vasodilatation occurred more frequent in the LET group than in the EMLA group (33 vs 3. P < 0.001). One subject with a history of atopy developed a rash at the LET application site.

Conclusion

Liposome-encapsulated tetracaine can provide a more effective topical anaesthesia than EMLA for intravenous catheterization after 60 min application. Clinical evaluations are necessary to determine the efficacy and safety of LET in providing topical anaesthesia for vanous invasive percutaneous procedures in other patient populations.     

Tetracaine gel vs EMLA cream for percutaneous anaesthesia in children

We have evaluated the anaesthetic effect of tetracaine gel 1 g, applied for 45 min, compared with EMLA cream 2 g, applied for 60 min, in a randomized, double-blind study in 60 children aged 3-15 yr. Venous cannulation was performed 15 min after removal of the EMLA cream (n = 20) and tetracaine gel (n = 20). Cannulation was performed up to 215 min after removal of the tetracaine gel in another 20 patients. Significantly lower pain scores were recorded by the children treated with tetracaine gel compared with EMLA cream (P < 0.02). Forty to 45% of children in the tetracaine groups reported no pain compared with only 10% in the EMLA group. Only minor adverse effects were observed. We conclude that tetracaine gel provided effective, rapid, long-lasting and safe local anaesthesia, and was significantly better than EMLA cream in reducing pain during venous cannulation in children using the recommended application periods for both formulations.      

Isobaric spinal anaesthesia with bupivacaine and tetracaine (author's transl)]

4 ml 0.5% solutions of bupivacaine and tetracaine without the addition of a vasoconstrictor, approximately isobaric, were used for spinal anaesthesia on patients in the sitting position. The sensory and motor block due to the two local anesthetics was tested and compared. The mean time on onset of complete analgesia was the same for both local anaesthetics (9 and 11 min), as was also the highest level of analgesia (T10). The duration of maximal extension of analgesia was on an average 45 min longer due to tetracaine (bupivacaine 105 min, tetracaine 150 min). The duration of maximal spread of the blocked sensation of pain, temperature, pressure and touch was similar for each of both local anesthetics. The regression of these sensory qualities, blocked in a dissoaciated manner, took a parallel course. With tetracaine the motor block of the lower extremities developed faster and lasted longer (Bromage 3 for bupivacaine 192 min, for tetracaine 220 min). Motor function and proprioception normalized in a synchronized manner. Isobaric spinal anaesthesia with these two solutions of local anaesthetics was found to be reliable and controllable, especially when administered to the sitting patient. Tetracaine is a good alternative to bupivacaine, currently controversial for intrathecal use.