Der Anaesthesist
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Randomized Controlled Trial Clinical Trial
[30 degree trunk elevation of the patient and quality of lumbar epidural anesthesia. Effects of elevation in operations on the lower extremities].
The spread and intensity of lumbar epidural anaesthesia are unpredictable. Moreover, segments L5 and S1 are frequently missed. In this study the effect of 30 degrees trunk elevation on the spread and intensity of lumbar epidural sensory and motor blockade and on the cardiovascular system were studied. ⋯ Patients in the hammock position had a clinically insignificant drop in systolic and diastolic blood pressure. In contrast to the young and healthy patients in this study, more severe cardiovascular changes might result in geriatric and/or ill patients subjected to a hammock position. For this reason, use of the technique in geriatric and/or ill patients requires special attention.
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Rocuronium bromide (Org 9426) is a new, non-depolarising steroidal muscle relaxant that is currently undergoing extensive clinical trials worldwide. Since it is expected to be introduced into clinical practice in the near future, the purpose of this review is to give a summary of the currently available information on this promising new compound. The search for the so-called ideal muscle relaxant [34] in the last years was focused on a non-depolarising compound that could replace succinylcholine for rapid intubation. ⋯ In initial clinical studies [13, 42] its most impressive features appeared to be rapid onset time and, more importantly, the rapid development of good intubating conditions. Thirty to 90 s after the injection of 0.6 mg/kg (2 x ED90), rocuronium provided intubating conditions that were equal to those observed after succinylcholine [9, 17, 31, 38]. Although the onset time of rocuronium at the adductor pollicis muscle is slower than that of succinylcholine, intubation with this compound can be performed faster than with any other non-depolarising agent.(ABSTRACT TRUNCATED AT 250 WORDS)
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Major conduction anaesthesia is not harmless. Based on new findings about sympathetic blockade, it was analysed whether circulatory side effects after spinal or epidural anaesthesia, in particular cardiocirculatory arrest, correlate with the level of segmental spread and whether prophylactic or therapeutic measures are effective. With spinal or epidural anaesthesia in healthy, unpremedicated patients, blood pressure, heart rate, and cardiac output remain within +/- 20% of normal independent of the height of segmental spread. ⋯ Infusion of crystalloid or colloid solutions may diminish the drop in blood pressure, whereas vasopressors reduce the frequency and extent of cardiocirculatory side effects. As yet, however, there is no safe prophylaxis to prevent cardiocirculatory arrest. Cardiopulmonary resuscitation after circulatory arrest must be combined with early administration of catecholamines.
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The paravertebral approach is the most common technique for local anaesthetic and neurolytic lumbar sympathetic blocks. However, guidelines on the site of needle insertion differ. As there have been several case reports on accidental trauma to the ureter and the kidney, this study was undertaken to evaluate the site of paravertebral needle insertion and the fluoroscopic landmarks for lumbar sympathetic blocks by computed tomographic puncture simulation. ⋯ However, a paravertebral approach of less than 6 cm may cause a lateral and ventral deviation of the needle from the sympathetic chain. Under fluoroscopy a correct needle position is obtained at an average distance of 0.5-0.8 cm dorsal to the anterior vertebral border, advancing the needle to the ventral border may cause an accidental puncture of the vena cava in more than 20% of patients undergoing nerve block of the right sympathetic chain. Furthermore, at the level of L2 inadvertent placement of the needle tip within the vertebral insertion of the diaphragm must be considered as a reason for atypical spread of contrast medium.
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Molecular genetic findings indicate genetic heterogeneity in susceptibility to malignant hyperthermia (MH). At present the in vitro contracture test (IVCT) is still the most reliable diagnostic procedure for MH susceptibility. It must be performed in a standardized fashion. METHODS. We investigated 350 patients (233 children and 117 adults) using the protocol of the European MH Group for the IVCT. The test results were classified as susceptible to MH (MHS), non-susceptible to MH (MHS), non-susceptible to MH (MHN) and equivocal (MHE), with an abnormal caffeine result designated MHEc and an abnormal halothane result designated MHEh. Reasons for the IVCT were a positive family history for MH susceptibility (n = 94), a MH reaction (n = 157), creatine kinase elevation unknown aetiology (n = 53) and different neuromuscular diseases (NMD, n = 46). Physical, neurological and laboratory work-up included serum enzymes, nerve conduction studies, electromyography and muscle biopsy evaluated by different techniques. Thirty-one children and 11 adults were MHS, while 152 children and 80 adults were MHN. MHE findings were obtained in 50 children and 26 adults. While the MHS and MHN groups are diagnostically safe, the equivocal group is not, with possible false-negative or false-positive interpretation. The high number of MHE findings most probably is explained by the high proportion of patients with NMD (53% of the children, 69% of the adults). RESULTS. In a group of 18 boys with Duchenne or Becker muscular dystrophy, ranging in age from 1.5 to 24 years, the IVCT results were twice MHS, once MHE, and MHN in the remaining 15 cases. In seven other boys with Duchenne or Becker muscular dystrophy, proven by molecular techniques, there were anaesthetic complications with MH-like symptoms. After administration of trigger substances, five out of the seven suffered a cardiac arrest, two of whom died. In the surviving five boys the IVCT results were three times MHN, once MHE and once MHS. Most probably these boys suffered from effects of succinylcholine, possibly potentiated by other trigger substances. The adverse cardiac reactions are attributed to triggered rhabdomyolysis with associated hyperkalemia but not a primary hereditary disposition to MH. ⋯ In patients with NMD, MHS and MHE test results do not indicate a hereditary, heterogeneous disposition to MH; the majority will be caused by a secondary induced disturbance of calcium homoeostasis in the diseased muscle cells. These results do, however, indicate the following: (1) Patients with NMD exposed to trigger substances are at higher risk than the general population for MH-like episodes, including sudden death. (2) NMD therefore should be diagnosed as early as possible and patients should not be exposed to trigger substances when alternatives are at hand. (3) Diagnostic procedures in patients having suffered an MH-like episode should include IVCT and special investigations to exclude or substantiate other NMD. The work-up may be changed if a family member is properly classified as MH susceptible. (4) In patients with known NMD there is no indication for performing IVCT, since the results may even be misleading.