Regional-Anaesthesie
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Four cases of unilateral spread of epidural anesthesia are presented. All were documented by X-ray epidurography. In two patients the catheter had passed immediately into one of the intervertebral foramina so that the local anesthetic had almost totally been injected into the paravertebral space. ⋯ This article discusses the fact that strands of the dorsomedian connective tissue band of the lumbar epidural space can cause catheters to coil up, be diverted, and not infrequently be directed into the next intervertebral foramen. These strands sometimes form a dense membrane, which together with the plica mediana of the dura mater prevent symmetrical spreading of epidurally injected fluids. When informing a patient about epidural anesthesia, the anesthesiologist should mention that anatomical variations in the epidural space can cause epidural anesthesia to spread unilaterally.
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Regional-Anaesthesie · Mar 1990
Case Reports[Complications of the postoperative use of lumbar epidural catheters in place for surgery].
Two cases of secondary subarachnoidal dislocation of lumbar epidural catheters are reported. The first catheter was placed, tested, and injected with 20 ml local anesthetic in order to achieve intraoperative anesthesia up to the T4 level. ⋯ Use of this catheter for postoperative analgesia led to total spinal anesthesia in spite of negative aspiration and test dose prior to injection of 7 ml local anesthetic. Implications of these two cases concerning placement procedures and monitoring during reuse of catheters placed some time before are discussed.
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Regional-Anaesthesie · Jan 1990
Biography Historical Article[Georg Perthes--a pioneer of modern regional anesthesia technics?].
In regional anesthesia, the localization of peripheral nerves and plexuses is possible by means of mechanical or electrical stimulation. Electrical stimulation for this purpose was first described in 1912 by the surgeon Georg Perthes (1869-1927) of Tübingen, who reported his own experiences. The original description and results of electrostimulation are transposed upon a modern point of view of regional anesthesia.
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Regional-Anaesthesie · Jan 1990
[Elimination of the obturator reflex as a specific indication for dilute solutions of etidocaine. A study of the suitability of a local anesthetic for reflex elimination in the 3-in-1 block technic].
Direct stimulation of the obturator nerve by the electroresectoscope during transurethral resection of tumors in lateral bladder regions is possible under regional or general anaesthesia without muscle relaxation. The resulting obturator reflex may lead to perforation of the bladder. Two different regional techniques can be used to interrupt the obturator reflex arc: (1) separate block of the obturator nerve; or (2) the "3-in-1 block" (Winnie). ⋯ Elimination of the obturator reflex is the only specific motor nerve block in anesthesia. Diluted etidocaine solutions seem to be adequate: irrespective the technique used for eliminating the reflex, diluted etidocaine produces a good effect and permits a dosage reduction compared with other local anesthetics. It is possible to block the obturator nerve bilaterally by "3-in-1 block" or unilaterally by "3-in-1 block" in combination with epidural analgesia within the recommended dose limits.
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Regional-Anaesthesie · Jan 1990
[The significance of the sampling site in the determination of plasma levels of local anesthetics using 0.75% bupivacaine as an example].
Knowledge of the actual concentrations of local anesthetic administered by various techniques is essential requisite when undesirable side effects and possible toxicity of a substance are to be evaluated. Therefore, numerous studies of plasma concentrations have been presented, which were carried out with the additional purpose of analyzing the kinetics of different local anesthetics with respect to limiting-value concentrations in the organism. Despite a sufficient degree of precision in the analysis of amide local anesthetics, it is uncertain whether the results of the different studies are comparable, because blood samples have been taken variously from peripheral veins, central veins or arteries. ⋯ The observed uniform differences in concentrations at the various sites of sampling can be explained by the fact that pulmonary uptake of local anesthetics causes the lower arterial levels. Especially in the early phase of resorption after administration of local anesthetics, the concentration in peripheral blood does not seem to be representative, because an equilibrium is not established between arterial and central venous blood until 30 min after administration at the earliest. In our opinion the peripheral venous concentrations are unreliable, particularly in the early phases, for the evaluation of unwanted effects or toxicity of local anesthetics, because the initial low values and the delayed increase in these could lead to a false sense of security.