Effects of complete heart block on myocardial function, morphology, and energy metabolism in the rat.

AIMS: Severe sustained bradycardia may cause acute and possibly chronic congestive heart failure (CHF). The aim of this study was to investigate acute and chronic effects of complete heart block (CHB) on cardiac function, morphology, and creatine (Cr) metabolism. METHODS AND RESULTS: CHB was induced in male Sprague-Dawley rats (approximately 250 g, n = 11) by means of electrocautery applied to the region of AV node and were compared with controls (n = 15). The rats were investigated at 1, 3, and 12 weeks after CHB induction with transthoracic echocardiography. Invasive haemodynamic assessment of left and right ventricular pressures was performed at 12 weeks. After the sacrifice, the hearts were freeze-clamped for analysis of myocardial Cr, and high energy phosphometabolites. The efficacy of operative procedure was 54%. The peri-operative mortality rate was 20%. Heart rate (HR) decreased by approximately 50% (P < 0.01) while stroke volume (SV) increased 2.5 times (P < 0.01) in the CHB rats. Cardiac index remained unchanged. The rats with CHB grew normally and were in no apparent distress. Filling pressures in left and right ventricles were normal. The CHB rats developed marked cardiomegaly with biventricular dilatation and eccentric left ventricular hypertrophy (P < 0.01). There was no change in the myocardial content of Cr and high energy phosphometabolites. CONCLUSION: Rats with CHB are compensating for reduction in HR with increased SV without haemodynamic and biochemical characteristics of CHF. This model may be useful to study the effects of CHB and bradycardia on myocardial structure, function, electrophysiology, and metabolism as well as for studies of cell therapy for reparation of AV conductance.     

交感神经节与椎旁阻滞联合运用于改善脑中风预后的研究

目的 评价交感神经节与椎旁阻滞联合运用在脑中风康复治疗中的效果。方法 150例中风患者随机分为交感神经节与椎旁阻滞联合运用组（SGB组）和康复训练组（H组）。分别在治疗前、治疗后及随访期间，记录患者的体征、实验室检查及特殊检测结果。使用临床神经功能缺损程度评分标准及修订的巴氏指数（modified Barthel index，MBI）评测。采用t检验和卡方检验分析组间差异。结果 治疗1、3、6个月后，SGB组与H组总疗效均有改善，分别为H组：50％、60％、70％；SGB组：90％、95％、100％，SGB组疗效优于H组。两组比较，自觉症状、神经功能缺损改善程度有明显差异，生活活动能力改善程度差别不大。治疗前、后相比，SGB组收缩压、舒张压、局部皮温、血高切黏度、血低切黏度、PGA有改善，H组改变不明显；两组患者血浆黏度无明显改善。TCD显示，SGB组脑血流改善占85．3％，H组占14．3％。SGB组住院时间短于H组，住院费用不增加。结论 在脑中风康复治疗中，联合运用交感神经节与椎旁阻滞，疗效明显优于常规康复训练。     

全麻复合硬膜外阻滞与单纯全麻的比较

比较全麻复合硬膜外阻滞和单纯全麻在围术期对机体应激、炎性、免疫等方面的影响。使用全麻加硬膜外麻醉能有效地抑制手术引起的应激反应，稳定循环状态，减少并发症，使病人在术中更为安全平稳，麻醉效果更为可靠，术毕清醒快，术后镇痛有利于术后病人咳嗽咯痰，并且能减轻围手术期对T细胞亚群的影响。     

Integrated home monitoring predicts lead failure in a pacemaker dependent 4-year-old girl.

A 4-year-old girl with post-surgical complete atrioventricular block received an epicardial dual chamber pacemaker system. During further growth intermittent exit block occurred, first misinterpreted as neurological seizures. The epicardial lead was replaced using a transvenous approach, and a pacemaker with an integrated home monitoring facility was implanted. After her discharge, a rise in the pacing threshold automatically initiated an event message. On the basis of this information, the patient was called in and imminent dislodgement of the ventricular lead was diagnosed by x-ray. The lead was repositioned and was found stable over 1-year follow-up.     

Peripheral Foot Blockade Versus Popliteal Fossa Nerve Block: A Prospective Randomized Trial in 51 Patients

The majority of foot and ankle operations are performed on an outpatient basis and often under some form of regional anesthesia. In this prospective, randomized study of 51 patients undergoing elective unilateral forefoot procedures, we compared 2 different anesthetic techniques: the peripheral foot blockade and the popliteal sciatic nerve block. Variables assessed included the quality of surgical anesthesia, postoperative analgesia, and the incidence of postoperative complications. The anesthesia was classified as effective if it was the sole anesthetic technique for the forefoot surgery. We found successful results in both groups: 92% in the foot block group and 96% in the popliteal block group. Analysis of time required to perform the anesthetic procedure showed a significant difference between the 2 groups, with foot block being considerably faster (14.3 minutes vs 19.2 minutes for popliteal block) (P = .0078). Foot block patients demonstrated 10.96 hours of analgesia, whereas popliteal block patients exhibited 14.32 hours (P = .132). With a mean follow-up of 5.7 months, we did not find anesthesia-related complications in any of the patients. Both techniques showed a high level of safety and efficacy, with no significant difference detected between them. Our patients showed a high rate of satisfaction with both procedures (96% for foot block patients and 96.1% for popliteal block patients) and reported a good discharge disposition. These data show that both procedures are safe and effective anesthetic techniques and well suited to forefoot ambulatory surgery.     

Oesophageal atresia: caudo-thoracic epidural anaesthesia reduces the need for post-operative ventilatory support

The mortality of neonates with oesophageal atresia in the Third World remains high because of delays in presentation and diagnosis. Lack of appropriate intensive care facilities is a further contributing factor. Caudothoracic epidural anaesthesia was used during surgical repair of oesophageal atresia in 35 patients in an attempt to minimise the need for post-operative ventionally support. This group was compared with 36 patients whose surgery was performed under general anaesthesia. The age at the time of referral, sex ratio, and weight were comparable in both groups. Using the Waterson classification, a greater number of poorer prognostic patients were seen in the epidural group (P <0.02). In all Waterson risk categories fewer patients required ventionally support post-operatively, which was statistically significant (P <0.01) when all categories were combined. We are encouraged by our results and believe this technique has a rôle in the management of neonates undergoing major surgery, both where neonatal intensive care exist or is deficient as in many parts of the Third World.     

Intercostal catheterization

Twenty-one patients scheduled to undergo thoracotomy or median sternotomy had intercostal catheters inserted pre-operatively. During thoracotomy, under direct vision, the spread of 20 ml of a solution containing bupivacaine and methylene blue was followed. In most cases the spread involved one or two intercostal spaces. However, in all but one patient, dye spread medially to the paravertebral space where it then spread in both caudad and cephalad directions to reach between two and five vertebrae. In three cases, dye was seen crossing the anterior surface of the vertebrae to reach the contralateral aspect. It is concluded that a major component of dermatomal block during intercostal catheterisations may be secondary to paravertebral spread.     

Epidural abscess following epidural steroid and local anaesthetic injection

Epidural abscess is a well-recognised but rare complication of epidural catheter placement. We have found only five previous reports of epidural abscess from noncatheter-related administration of steroids and/or local anaesthetic. We describe a further case which led to critical illness and emphasise the association between diabetes mellitus and epidural infection.