Epidural block for obstetrics: Comparison of bolus injection of local anesthetic with gravity flow technique

Study Objective: To test the hypothesis that slow administration of local anesthetic into the epidural space by gravity flow reduces the incidence of signs and symptoms of unintended injection.

Design: Prospective, randomized study.

Setting: Teaching hospital.

Patients: 600 ASA physical status I and II parturients scheduled for labor and delivery or elective cesarean section.

Interventions: After identification of the epidural space with pulsations of an air-fluid column, parturients for vaginal delivery (n = 380) were randomized to receive a test dose of 3 ml 3% 2-chloroprocaine with epinephrine 20 μg, two doses of 7 ml bupivacaine 0.03 % with sufentanil 1 μg/ml and epinephrine 2 μg/ml by either gravity flow (Group 1) given over 30 seconds or by bolus injection (Group 2) given over 5 seconds through the epidural needle; parturients for Cesarean delivery (n = 220) were randomized to receive a test dose and two doses of 6 ml lidocaine 2 % with sufentanil 1 μg/ml and epinephrine 2 μg/ml by either gravity flow or by bolus injection through the epidural needle. Changes in maternal heart rate (HR) and blood pressure, signs of intravascular injection, and adverse effects of epidural bupivacaine-sufentanil were recorded after each dose.

Measurements and Main Results: Gravity flow administration (Group 1) was associated with a smaller increase in mean maternal HR (p < 0.001), less hypotension (p < 0.01), sedation (p < 0.01), nausea (p = 0.01), and segmental spread (p < 0.0001) than were corresponding doses given by traditional bolus injection (Group 1) for vaginal or Cesarean deliveries. The incidence of systemic toxicity was zero of 300 (0%) with gravity flow and 4 of 300 (1.3%) by bolus injection, p = 0.12, Fisher's exact test. No patient in either group had an accidental intrathecal injection.

Conclusion: Gravity flow administration of local anesthetic-opioid solution during epidural block for obstetrics was associated with fewer signs of systemic drug absorption and cardiovascular perturbations than was the traditional bolus injection. This study supports the current opinion that slow administration of local anesthetic during epidural black contributes to fewer adverse events.     

高原地区人胎儿脊柱的生长发育

本文用X线摄片的方法,对西宁地区胎龄为17—36周的60例胎儿脊柱的骨化及生长动态进行了研究。结果:1、提供了高原地区人胎儿脊柱长轴生长发育的资料。脊柱各段以胸段为最长,其次为腰、颈、骶段。2、计算出胎龄与脊柱各段长度间的回归方程,据此可以胎龄推算脊柱的长度,反之亦可以脊柱的长度估计胎龄。3、报道了颈、骶、尾段亿发骨化点出现顺序的规律。     

Effects of famotidine and cimetidine on plasma levels of epidurally administered lignocaine

The effects of two H2-receptor antagonists, famotidine and cimetidine, on the plasma levels of epidurally administered lignocaine were studied. Group A (n = 20) received famotidine 20 mg orally the night before surgery and 20 mg intramuscularly 60 minutes before induction of anaesthesia. Group B (n = 15) received cimetidine 200 mg orally the night before the surgery and 400 mg orally 60 minutes before the anaesthetic induction. Group C (n = 20) received neither famotidine nor cimetidine and served as controls. Twelve millilitres of 2.0% lignocaine with adrenaline 1:200,000 was injected into the epidural space in all patients, after the establishment of general anaesthesia with nitrous oxide, oxygen, and enflurane (0.3-0.5%). The patients who received cimetidine showed significantly higher plasma concentrations of lignocaine compared with either group A or group C at all investigation times (p less than 0.01). The mean peak plasma concentrations were 2.4 (SEM 0.1), 3.2 (SEM 0.2) and 2.3 (SEM 0.1) micrograms/ml in group A, B, and C, respectively. This study suggests that famotidine is preferable to cimetidine for control of gastric acidity before the use of lignocaine as the epidural anaesthetic.     

维持肢体正常的运动感觉功能所需最少神经根数的实验研究

目的 研究臂丛神经根单发断，２根切断（不同方式联合）及３根切断后对肢体的影响，为治疗臂丛根性撕脱伤寻找更多的潜在移位神经，方法 ２５２只ＳＤ大鼠随机分为１３组：（１）第１－５组（单根神经根切断组）；每组１２只大鼠。分别切断Ｃ５－８Ｔ１各神经根；（２）第６－１２组（２根神经根切断组）；每组２４只大鼠。分别切断相邻及不相邻２根神经根，即Ｃ５，６，Ｃ６，７，Ｃ７，８，Ｃ８Ｔ１，Ｃ５，７，Ｃ６，８和Ｃ７Ｔ     

Transplantation of embryonic noradrenergic neurons in two models of adult rat spinal cord injury: ultrastructural immunocytochemical study

The synaptic connections established by grafted noradrenergic (NA) neurons into the lesioned adult rat spinal cord were analysed using immunocytochemistry at the electron microscopic level. An embryonic cell suspension of the locus coeruleus region from E-13 rat embryos was transplanted into the spinal cord following either: (1) spinal cord transection or (2), partial selective denervation by 6-hydroxy dopamine (6-OH DA). One month after grafting, the NA-neurons established, in the two models, an innervation pattern similar to that found in the intact spinal cord. In both models, the transplanted NA-immunoreactive neurons formed extensive synaptic contacts with dendrites, spines and perikarya. The proportion of axodendritic and axospinous contacts was inverse in the two models. The first model thus reproduced more closely the normal synaptic pattern prefering dendritic targets, which could correspond to a better integration of the graft. In the second model, a partially NA-denervated spinal cord, there existed a competition between residual intrinsic and grafted neuron-derived fibres, which presumably affects synaptogenesis. In conclusion, the present study illustrate the complexity of cell interations conducting to the formation of a specific circuitry. Recognition phenomenon are likely modulated by space constraints, which ultimately shape-up the geometry of synaptic contacts.     

胚胎脊髓细胞悬液植入急性成年大鼠损伤脊髓

目的：建立胚胎脊髓细胞悬液移植于脊髓损伤模型，以评价其治疗脊髓损伤的可能性。方法：４２只Ｗｉｓｔａｒ大鼠以改良Ａｌｅｎ法（５０ｇｃｍ）打击脊髓，３天后将孕１４天（Ｅ１４）ＦＳＣＳ２０μｌ植入损伤空腔，移植后２、４、６、８、１０、１２周，以光、电镜、免疫组织化学观察移植物存活、分化及其与宿主之间关系。结果：移植细胞逐渐长大。充满不规则空腔，宿主ＮＦ、５－ＨＴ、ＣＧＲＰ纤维分别出现于移植物，ＧＦＡＰ纤维于宿主移植物交界处适量存在。移植成神经细胞、成少突胶质细胞、成星形细胞的细胞器日渐完善，细胞功能活跃。复杂及多样突触与细胞连接，将上述细胞与神经纤维、胶质纤维、毛细血管网在三维空间内连接成一体，并与宿主紧密嵌合。结论：（１）成年大鼠脊髓损伤３天后植入ＦＳＣＳ可以存活。（２）移植物进入宿主后，出现再分布，继而器官样分化。（３）长、短传导束进入移植物，显示了移植物的桥作用。（４）成少突胶质细胞的神经营救作用。（５）移植区内出现多种突触，提示移植物中继作用的可能性。     

Epidural pethidine and bupivacaine in labour

A double-blind randomised study was performed to assess the value of the addition of pethidine 50 mg to the initial dose of bupivacaine given for epidural analgesia in labour. Forty-nine patients received either 1 ml of saline (n = 24), or 50 mg of pethidine (n = 25), added to 9 ml of 0.25% bupivacaine as an initial injection for intrapartum epidural analgesia. There was a significant increase in the mean duration of analgesia in the pethidine group. However, pethidine did not increase the speed of onset of analgesia, or improve the quality of analgesia.     

Spinal cord sarcoidosis

We present a case of spinal cord sarcoidosis which resembled a disseminated intramedullary tumour. The case is unusual because the spinal cord is only rarely affected by sarcoidosis and the patient developed a neurological deficit as the first manifestation of the disease. This condition thus has to be considered in the differential diagnosis of primary intramedullary tumours, or metastatic disease with involvement of the spinal cord.     

氟骨症性椎管狭窄症的手术治疗

１９８７～１９９０年手术治疗氟骨症性椎管狭窄症１００例。包括颈椎９例，胸椎８例，腰、骶椎８３例。术后随访１～４年，复查结果：临床治愈９３例（９３％）：显效３例（３％）、有效３例（３％）、无效１例（１％）。手术原则是彻底减压，因氟骨症具有椎骨及其骨周组织严重退变、异化和骨化的临床病理特点，故在胸、腰椎减压术后，一般不影响其稳定性，在颈椎施行双开式或单开式椎管扩大加植骨融合术，则可收减压、稳定及防止或减少椎板间隙瘢痕狭窄的效果。     

椎板后移回植的椎管扩大术治疗椎管狭窄症

作者报告棘突劈开、椎板后移回植的椎管扩大术治疗椎管狭窄症１８２例，使椎管容积扩大３４．８％，横径扩大３．８ｍｍ，矢径扩大６．１ｍｍ。随访２年９个月，优良率８６．６％，椎板愈合率９６．９％。本文探讨少数椎板迟延愈合的原因和预防措施，如斜切椎板、缝合固定和腰背筋膜与棘上韧带悬吊缝合等。术后卧床１０～１２周，用石膏型保护。作者认为本法能有效的预防术后脊柱不稳，顽固性腰痛等并发症。