布比卡因药物体积对犬硬膜外麻醉效果的影响

本次试验旨在探究不同体积布比卡因用于犬硬膜外麻醉对感觉阻滞和运动阻滞的影响,比较盲扎与神经刺激器引导犬硬膜外麻醉的成功率。试验分为6个试验组,BL组(3组)利用解剖结构定位并进行硬膜外麻醉,S组(3组)利用神经刺激器引导进行硬膜外麻醉。注射药物后持续监测犬的体征变化、感觉阻滞(Sensory blockade,SB)、运动阻滞程度(Motor blockade,MB)等指标,直至犬完全恢复。试验结果表明,使用0.5%布比卡因进行犬硬膜外麻醉产生感觉阻滞和运动阻滞的持续时间和阻滞程度随药物体积增加(0.1 mL/kg·bw、0.2 mL/kg·bw、0.4 mL/kg·bw)而增加。盲扎法与神经刺激器法对硬膜外麻醉的成功率无显著影响。     

犬剖腹产的全身麻醉

犬剖腹产中,麻醉是确保母犬安全和仔犬存活的关键因素.剖腹产麻醉要求对活的胎儿影响最小,对母体的抑制作用最小,为剖腹产的实施提供麻醉.剖腹产可采用硬膜外麻醉和全身麻醉,目前我们在临床上多采用后者.     

不同麻醉方法在犬剖腹产手术的临床效果

为探究不同麻醉方法对犬剖腹产手术的应激效果及仔犬的生活容态。本试验采用846合剂全身麻醉、普鲁卡因硬膜外腔麻醉及846合剂与普鲁卡因联合麻醉对怀孕期满的犬进行剖腹产手术,在剖腹产手术的麻醉前(T1)、切开腹壁(T2)、手术30min(T3)、手术完(T4)、术后24h(T5)、术后48h(T6)进行静脉采血,检测血浆皮质酮和血糖含量,比较术后幼犬平均日增重及生活容态。结果表明:846麻醉组和硬膜外麻醉组血浆皮质醇质量浓度在T2⁶这5个时期显著高于自然分娩组和联合麻醉组(P<0.05),联合麻醉组仅在T3时血浆皮质醇质量浓度显著高于自然分娩组(P<0.05);846麻醉组和硬膜外麻醉组血糖质量浓度在T26这5个时期显著高于自然分娩组和联合麻醉组(P<0.05),联合麻醉组仅在T3时血浆皮质醇质量浓度显著高于自然分娩组(P<0.05);846麻醉组和硬膜外麻醉组血糖质量浓度在T2⁶时期均显著高于自然分娩组及联合麻醉组(P<0.05),联合麻醉组仅在T36时期均显著高于自然分娩组及联合麻醉组(P<0.05),联合麻醉组仅在T3⁴时期显著高于自然分娩组(P<0.05);联合麻醉组中的幼犬增重、生活容态与自然分娩时幼犬最接近,846麻醉组效果较差,硬膜外麻醉组效果最差。本研究证明846合剂与普鲁卡因硬膜外腔联合麻醉方法能够更有效缓解犬剖腹产手术的应激反应。     

复合麻醉药物对犬的麻醉效果比较

复方８４６、静松灵／氯氨酮，氯丙嗪／氯氨酮、氯丙嗪／乙醚、氯丙嗪／静松灵、分别作用于犬，均可获得一定时间的麻醉效果。通过麻醉前、后体温（Ｔ℃）、呼吸（Ｒ）、脉搏（Ｐ），镇痛反应，麻醉维持时间的检测；通过麻醉后手术安静顺利情况；从伤口愈合情况表明：几组药物作用于犬后，体温差异不显著（Ｐ＞０．０５，呼吸、脉搏部分呈显著性变化（Ｐ＞０．０５）。镇痛作用以８４６为好，其次为静松灵／氯氨酮，氯丙嗪／静松灵、氯丙嗪／氯氨酮、氯丙嗪／乙醚；麻醉维持时间以８４６最长（１３．７０±９．６６），其次为静松灵／氯氨酮（８９±９．９）；从手术安静顺利情况看，复方８４６、静松灵／氯氨酮优于其它组；从伤口愈合情况看，静松灵／氯氨酮优于其他组。综合比较：复方８４６、静松灵／氯氨酮，用于犬的临床麻醉，效果确实。     

犬猫的注射麻醉

麻醉作为一种动物保定方法,广泛地应用于小动物疾病的诊断、治疗和外科手术.麻醉分为吸入麻醉、非吸入(注射)麻醉和局部麻醉,目前适用于小动物临床的主要是非吸入麻醉.选择理想的麻醉药物和麻醉方法,是手术成功与否的关键.也是小动物诊疗的重要环节.论文介绍了犬猫注射全身麻醉的方法,麻醉前准备,常用麻醉药物以及如何应用联合用药来取长补短对犬猫实施全身麻醉等.     

比格犬的麻醉及麻醉前用药

比格犬是国际通用的标准化实验用犬,在药理学、毒理学、外科学、微生物学等多个领域有广泛的应用.论文综述了比格犬麻醉技术的研究进展,包括吸入麻醉、注射麻醉、复合麻醉以及麻醉前给药等,以期为科研人员开展比格犬相关麻醉操作提供参考.     

比格犬氟烷吸入麻醉的临床观察

随着兽医科学的发展，吸入麻醉由于具有较容易和迅速地控制麻醉深度，任意延长麻醉时间，麻醉后苏醒快，对动物生理活动干扰少和麻醉副作用小等优点，正逐渐被应用于小动物临床。氟烷(又叫三氟乙烷，三氟溴氯乙烷)作为卤族类吸入麻醉药的代表，为无色透明的液体，不燃烧，不爆炸，对呼吸道无刺激，麻醉作用快，可控性好，在国外被广泛应用于大小动物临床，但在我国临床应用还较少，有鉴于此，我们进行了如下实验。     

The volume effect of lidocaine on thoracic epidural anesthesia in conscious Beagle dogs

ObjectiveTo evaluate the volume effect of local anesthetic solution on thoracic epidural analgesia in dogs.Study designProspective, experimental trial.AnimalsFive healthy adult Beagle dogs weighing 9.7 ± 1.3 kg.MethodsA catheter was inserted into the seventh thoracic epidural space using a lumbosacral approach, and secured with suture under total intravenous (IV) anesthesia with propofol. Each dog was administered four volume treatments (0.05, 0.10, 0.15 and 0.20 mL kg⁻¹) of 2% lidocaine via the catheter at 12 hour intervals. In every treatment, dogs were re-anesthetized with propofol (6 mg kg⁻¹, IV) and isoflurane, and received iohexol at each volume to visualize the epidural distribution (ED) through computed tomography. Three hours after epidurography, when dogs had recovered from anesthesia, the appropriate volume of lidocaine was injected through the catheter, and sensory blockade (SB) in dermatomes was evaluated by pinching with a mosquito forceps. Results were presented as median (range), and the volume effect on ED and SB was analyzed with one-way Kruskal–Wallis anova.ResultsIn proportion to volumes (0.05, 0.10, 0.15 and 0.20 mL kg⁻¹), there were significant increases in the extent of ED from 7.4 (5.5–9.0) to 10.4 (8.0–12.0), 13.2 (12.5–13.0), and 15.2 (13.0–18.0) vertebrae, respectively, p < 0.001, and in SB from 2.7 (1.0–5.0) to 6.8 (4.5–10.5), 9.9 (6.5–13.0), and 13.1 (11.0–15.0) dermatomes, respectively, p < 0.001. Unilateral ED and SB were observed in all treatments with various grades, and this distribution was more frequent in the low volume treatments. In the high volume treatments, temporary complications including Horner's syndrome, ataxia, paraplegia, depression, stupor, and intermittent cough occurred often.Conclusions and clinical relevanceThe increase in volume of local anesthetic solution improved SB by resulting in more consistent bilateral dermatome blockade as well as an extended blockade. However, caution should be exerted, as higher volume injections of lidocaine caused side effects in all dogs.     

Evaluation of perfusion index as a noninvasive tool to determine epidural anesthesia effectiveness in dogs

ObjectiveTo evaluate perfusion index (PI) as a noninvasive tool to determine effectiveness and onset of epidural anesthesia in dogs.Study designProspective clinical trial.AnimalsA total of 21 adult dogs, aged 6.5 ± 3 years and weighing 34.9 ± 6.4 kg, undergoing a tibial plateau leveling osteotomy.MethodsDogs were premedicated intramuscularly with acepromazine (0.03 mg kg^–1) and hydromorphone (0.1 mg kg^–1) and anesthetized with intravenous propofol (to effect) and isoflurane in oxygen. A surface transflectance probe was secured to the tail base to monitor PI and a dorsal pedal artery catheter was placed for invasive blood pressure monitoring. A lumbosacral epidural was performed with the dog in sternal recumbency. Dogs were randomly assigned for inclusion of epidural morphine (0.1 mg kg^–1) or morphine (0.1 mg kg^–1) and lidocaine (4 mg kg^–1). PI was recorded following instrumentation of each dog just prior to the epidural (baseline), at 10 minute intervals for 30 minutes, before and after the surgical skin incision and before and after completion of the osteotomy. Physiological variables and end-tidal isoflurane were recorded at the same time points.ResultsThere was no significant difference in PI between the groups at any time point. There was a significant change in end-tidal isoflurane before and after the skin incision in the epidural morphine and epidural morphine–lidocaine groups (p = 0.04, p = 0.05, respectively) and before and after the osteotomy in each group for heart rate (p = 0.001, p = 0.04), diastolic (p = 0.01, p = 0.01) and mean arterial blood pressure (p = 0.03, p = 0.05).Conclusions and clinical relevancePI did not provide an objective means for determining the onset or effectiveness of epidural anesthesia in anesthetized dogs and alternate methods of noninvasive assessment should be investigated.     

Cranial versus caudal thoracic epidural anesthesia using three volumes of lidocaine in conscious Beagle dogs

Objective

To compare the effects of epidural injection of three volumes of lidocaine injected at the third (T3) or eleventh thoracic vertebra (T11) in conscious dogs to induce thoracic epidural anesthesia (TEA) and to measure the epidural dispersion of iohexol under similar conditions.

Spinal epidural empyema in seven dogs

OBJECTIVE: To characterize the clinical signs, diagnostic and surgical findings, and outcome in dogs with spinal epidural empyema (SEE). STUDY DESIGN: Retrospective study. ANIMALS: Seven dogs. METHODS: Dogs with SEE between 1992 and 2001 were identified from a computerized medical record system. Inclusion criteria were: neurologic examination, vertebral column radiographs, myelography, antimicrobial culture and susceptibility of material collected surgically from the vertebral canal, a definitive diagnosis of SEE confirmed by surgery, and microscopic examination of tissue from the vertebral canal. RESULTS: Common signs were lethargy, fever, anorexia, apparent spinal pain, and paraparesis/plegia. Common laboratory abnormalities were peripheral neutrophilia, and neutrophilic pleocytosis in cerebrospinal fluid (CSF). Three dogs had concurrent discospondylitis and 1 of these had vertebral luxation. On myelography, extradural spinal cord compression was focal (2 dogs), multifocal (3), or diffuse (2). Bacteria were isolated not from CSF but from blood, surgical site, pleural fluid, or urine in 6 dogs. Dogs were administered antibiotics and had surgical decompression by hemilaminectomy. Five dogs improved neurologically and had a good long-term outcome. Two dogs were euthanatized, 1 because of worsening of neurologic signs and pneumonia, and the other because of herniation of a cervical intervertebral disc 1 month postoperatively, unrelated to the SEE. CONCLUSION: Dogs with SEE may have a good outcome when treated by surgical decompression and antibiotic administration. CLINICAL RELEVANCE: SEE should be included in a list of possible causes for dogs with fever, apparent spinal pain, and myelopathy.     

Cardiovascular effects of epidural blocks in dogs

Cardiovascular and respiratory function was studied after epidural injection of lignocaine hydrochloride (3 mg kg¹) at the lumbosacral space in dogs premedicated with methadone (0–8 mg kg¹), acepromazine (0.3 mg kg¹) and atropine (0.6 to 1.2 mg). Analgesia was produced caudal to the third to fifth thoracic dermatomes; there was no significant change in cardiovascular function, respiratory rate, arterial blood pH or blood gas tensions. Relaxation of the hind leg and abdominal muscles was profound and haemorrhage caused a rapid fall in arterial blood pressure accompanied by tachycardia.     

The effect of epidural injection speed on epidural pressure and distribution of solution in anesthetized dogs

ObjectiveTo determine the effect of injection speed on epidural pressure (EP), injection pressure (IP), epidural distribution (ED) of solution, and extent of sensory blockade (SB) during lumbosacral epidural anesthesia in dogs.Study designProspective experimental trial.AnimalsTen healthy adult Beagle dogs weighing 8.7 ± 1.6 kg.MethodsGeneral anesthesia was induced with propofol administered intravenously and maintained with isoflurane. Keeping the dogs in sternal recumbency, two spinal needles connected to electrical pressure transducers were inserted into the L6-L7 and the L7-S1 intervertebral epidural spaces for EP and IP measurements, respectively. Bupivacaine 0.5% diluted in iohexol was administered epidurally to each dog via spinal needle at L7-S1 intervertebral space, at two rates of injection (1 and 2 mL minute^?1 groups), with a 1-week washout period. Epidural distribution was verified with computed tomography, and SB was evaluated after arousal by pinching the skin with a mosquito hemostatic forceps over the vertebral dermatomes. The results were analyzed according to each injection speed, using paired t- and Wilcoxon signed-rank tests.ResultsMean ± SD of baseline EP and IP values were 2.1 ± 6.1 and 2.6 ± 7.1 mmHg, respectively. Significant differences were observed between 1 and 2 mL minute^?1 groups for peak EP (23.1 ± 8.5 and 35.0 ± 14.5 mmHg, p = 0.047) and peak IP (68.5 ± 10.7 and 144.7 ± 32.6 mmHg, p <0.001). However, the median (range) of the ED, 11.5 (4–22) and 12 (5–21) vertebrae, and SB, 3.5 (0–20) and 1 (0–20) dermatomes, values of the two groups were not related to injection speed.Conclusions and clinical relevanceThe EP profile during injection was measured by separating the injection and pressure monitoring lines. The increase in epidural injection speed increased the EP, but not the ED or the SB in dogs.     

Pharmacokinetics of epidural butorphanol in isoflurane-anaesthetized dogs

Sixteen healthy male dogs were used at random in this protocol. The dogs were anaesthetized with isoflurane in oxygen. Eight of the dogs received 0.25 mg/kg of butorphanol (group B) and the others an equal volume of isotonic saline (group S) administered by a catheter inserted in the lumbosacral epidural space. Butorphanol concentrations in plasma and cerebrospinal fluid (CSF) were measured using high-performance liquid chromatography with electrochemical detection. Maximum concentration of butorphanol and time to obtain this concentration were 42.28 ng/mL at 13.88 min in blood, and 18.03 ng/mL at 30 min in CSF. Volume of distribution, clearance, mean distribution and elimination half-lives were respectively 4.39 L/kg, 2.02 L/h.kg, 16.5 min and 189.1 min. Mean isoflurane minimal alveolar concentration values for group B obtained following hind- or forelimb stimulation decreased by 31% after epidural butorphanol. Cutaneous analgesia (to pin-prick test) persisted for 3 h after the end of isoflurane anaesthesia in group B and was in correlation with the plasmatic analgesic dose of butorphanol (9 ng/mL). These results suggested that analgesia was predominantly obtained by action of butorphanol on the supraspinal structures following its vascular systemic absorption.     

The use of ultrasound to assist epidural injection in obese dogs

ObjectiveTo evaluate the use of ultrasound for identifying the site for needle puncture and to determine the depth to the epidural space in obese dogs.Study designProspective study in dogs undergoing elective orthopedic surgery.AnimalsA group of seven obese Labrador male dogs aged 6.93 ± 2.56 years and weighing 46.5 ± 4.1 kg (mean ± standard deviation).MethodsThe anesthetic protocol for these dogs included epidural anesthesia. With the dogs anesthetized and positioned in sternal recumbency with the pelvic limbs flexed forward, ultrasound imaging was used to locate the lumbosacral intervertebral space. Intersection of dorsal and transverse lines about the probe identified the point of needle insertion. A 17 gauge, 8.9 cm Tuohy needle was inserted perpendicularly through the skin and advanced to the lumbosacral intervertebral space. The number of puncture attempts was recorded and needle depth was compared with skin to ligamentum flavum distance.ResultsEpidural injection was performed in all dogs at the first attempt of needle insertion. The distance from skin to epidural space was 5.95 ± 0.62 cm measured by ultrasound and 5.89 ± 0.64 cm measured with the Tuohy needle. These measurements were not different (p = 0.26). A highly significant correlation coefficient of 0.966 between measurement techniques was obtained (p < 0.001).Conclusions and clinical relevanceUltrasound imaging identified the point of needle insertion for lumbosacral epidural injection in seven obese dogs. The results indicate that ultrasound can be used to locate the lumbosacral intervertebral space and identify an appropriate point for needle insertion to perform epidural injection.