Combined spinal-epidural anesthesia for outpatient surgery. Dose-response characteristics of intrathecal isobaric lidocaine using a 27-gauge Whitacre spinal needle

Leukotriene A4 (LTA4) hydrolase is a bifunctional zinc metalloenzyme which catalyzes the final step in the biosynthesis of the proinflammatory leukotriene B4 and which also possesses a peptidase activity. From sequence comparisons with aminopeptidases, a tyrosine at position 383 in LTA4 hydrolase has been suggested as a possible catalytic amino acid. To explore the potential role of this amino acid in catalysis, we replaced the tyrosine residue with phenylalanine, histidine or glutamine residues by site-directed mutagenesis. The mutated cDNAs were expressed in Escherichia coli and the resulting recombinant proteins, named [Y383F]LTA4 hydrolase, [Y383H]LTA4 hydrolase and [Y383Q]LTA4 hydrolase, were purified to homogeneity to allow assays of both the epoxide hydrolase activity, i.e. the conversion of LTA4 into leukotriene B4, and the peptidase activity. None of the mutated proteins exhibited significant peptidase activities, all of them showing activities less than 0.3% that of the wild-type enzyme. The epoxide hydrolase activity was not affected to the same degree and corresponded to 11, 16 and 17% that of the unmutated enzyme for [Y383F]LTA4 hydrolase, [Y383H]LTA4 hydrolase and [Y383Q]LTA4 hydrolase, respectively. Kinetic analysis was performed with the mutant [Y383Q]LTA4 hydrolase, which revealed an approximately 10-fold increase in Km for leukotriene A4 compared to that for the unmutated enzyme. At high concentrations of substrate, the difference in enzyme velocity was only moderate, with Vmax values of 600 nmol.mg-1.min-1 and 1000 nmol.mg-1.min-1 for [Y383Q]LTA4 hydrolase and the wild-type enzyme, respectively. No such effect of substrate concentration could be observed on the peptidase activity. As a positive control, we exchanged a glycine residue in position 386 for an alanine residue, and the recombinant protein, [G386A]LTA4 hydrolase retained 19% and 77% of the peptidase and epoxide hydrolase activities, respectively. The results from this study are consistent with a role for Tyr383 in the peptidase reaction of LTA4 hydrolase, where it may act as a proton donor in a general base mechanism. However, our data do not allow a similar interpretation for the mechanism involved in the hydrolysis of LTA4 into LTB4.     

Comparison of continuous spinal anaesthesia using a 32-gauge catheter with anaesthesia using a single-dose 24-gauge atraumatic needle in young patients

One hundred and twenty-eight ASA I-III patients less than 40 yr of age, undergoing orthopaedic or trauma lower limb surgery, were allocated randomly to receive either continuous spinal anaesthesia (CSA) using a 32-gauge polyimide microcatheter with a permanent stylet (Rusch/TFX Medical, Duluth, GA, USA) or single-dose spinal anaesthesia (SDSA) with a 24-gauge x 103-mm Sprotte spinal needle (Pajunk, Germany). Plain bupivacaine (0.5%) was used as the local anaesthetic. The initial doses were 1 ml (5 mg) of CSA and 3 ml (15 mg) of SDSA, while the re-injection doses were 1 ml (5 mg) in the CSA group. SDSA was quicker to perform: mean 4.4 (SD 1.6) min compared with 6.2 (2.6) min for CSA (P < 0.01). Times to onset and surgical anaesthesia were also significantly greater in the CSA group (P < 0.01). The quality of the block was better in the SDSA group (P < 0.05), but was associated with greater haemodynamic instability (P < 0.05). The segmental level of analgesia was significantly lower in the CSA group (median T10 (range T12-T8)) than in the SDSA group (T9 (T11-T5)) (P < 0.05). There were no significant differences in the incidence of postoperative complications, with two mild spinal headaches in both groups. We conclude that CSA using a microcatheter in young patients is difficult to perform and affords no advantages over SDSA with a small gauge atraumatic needle.     

Postdural puncture headache and back pain after spinal anesthesia with 27-gauge Quincke and 26-gauge Atraucan needles

A 17-residue peptide containing the caulimovirus-related "zinc finger' was prepared by solid-phase peptide synthesis. Fluorescence measurements showed that the tryptophan quantum yield was Zn(2+)-dependent, allowing a 1:1 a stoichiometry for the complex to be determined. The structure of the peptide was characterized using circular dichroic spectroscopy, which indicates that the peptide exhibits a random coiled conformation in the absence of zinc but appears to form an ordered structure in the presence of zinc.     

Side reaction after lumbar myelography with dimer-x (author's transl)

The existence of several very impressive spinal paroxysms after lumbar myelography with Dimer-X1 caused us to make a retrospective investigation of 327 patients with 355 myelographies. In 7.1% of the investigations we have found partly heavy, but mostly reversible neurological complications. The latter cannot be classified, contrary to prevailing statements, in spinal, meningeal or cerebral reactions, since mostly all 3 anatomical structures are being concerned. Corresponding casuistical information are being presented and with their neurological symptomatic discussed. The spinal paroxysms appeared approximately 6 hours after the myelography and lasted over 8-10 hours, in spite of intensive therapeutical efforts. The pathogenesis points to a multifactorial occurrence caused by the coincidence of an increased dosage of the contrast media, too bed rest time, rising of the contrast media in the spinal cord zone and disturbed liquor fluid circulation and contrast media resorption. Pathophysiologically is in connection with spinal cramps an epileptic mechanism probable. Additional spinal reflexive components could be an explanation for the little therapeutical effect of Diacepam (Valium), which is contrary to the statement in the literature. We have seen a better effect in particular cases with Phenothiazine. With strict observance of specific precautionary measures, the Dimer-X seems to be a good media for the presentation of the lumbar subarachnoid space. A further development in this field is desirable.     

Insertion characteristics and complications of a new spinal needle 26-gauge Atraucan

We evaluated the insertion characteristics and complications of a new spinal needle 26-gauge Atraucan (group A) compared with 27-gauge Whitacre (group W) in 100 patients undergoing orthopedic surgeries of the lower extremities. Spinal anesthesia was performed in the lateral decubitus position and 0.40-0.5% tetracaine 1.6-2.5 ml was injected through the L 3/4 or L 4/5 interspace. The tactile appreciation of dural presentation with the needle (dural click) was higher in group W (89.8%) than in group A (42.6%) which the back flow of cerebrospinal fluid was not recognized within three punctures was in 2 cases (4%) in group A and in 1 case (2%) in group W. In these 3 cases, spinal anesthesia was performed easily using 25-gauge Whitacre. In group A, the spinal needle could be inserted without using an introducer in 35 cases (70%). The incidence of the postoperative headache or back pain was low and postdural puncture headache (PDPH) did not occur in both groups. We conclude that 26-gauge Atraucan can be handled easily and useful for preventing PDPH.     

Thoracic and lumbar myelography with metrizamid (author's transl)

With the new x-ray medium Metrizamid it is possible to perform almost complication-free lumbar and thoracic myelography. In an experience the type of complications arising were reduced to moderate headaches, mild nausea occasional dissiness. No convulsions were seen. The number of complications are less than with other watersoluble contrast medium.     

Magnetic resonance myelography (MRM) as a spinal examination technique

PURPOSE: Conventional myelography involves side effects and complications due to puncture of CSF space and injection of contrast medium. On the other hand, MR-myelography (MRM) is a new noninvasive method requiring neither puncture nor contrast medium and causing no side effects. The diagnostic value and accuracy of MRM was evaluated in comparison with conventional myelography. MATERIALS AND METHODS: In this prospective comparative study, 41 patients (17 male, 24 female, mean age 42 years) with radicular symptoms underwent conventional lumbar myelography and were also submitted to MRM. Evaluation was performed in a blind manner by two independent examiners. RESULTS: The specificity and sensitivity of the methods are identical. MRM shows 35 cases of thecal indentation with amputation of a nerve root sheath and 6 cases of spinal stenosis. The results of conventional myelography and MRM were surgically confirmed in 38 patients. CONCLUSIONS: Both methods have the same diagnostic accuracy, but MRM requires neither puncture nor contrast medium nor x-rays.     

Biphasic response of spinal GABAergic neurons after a lumbar rhizotomy in the adult rat

The expression of gamma-aminobutyric acid (GABA) and of the isoforms of the enzyme involved in its synthesis, glutamic acid decarboxylase (GAD), is modified in several rat brain structures in different injury models. The aim of the present work was to determine whether such plasticity of the GABAergic system also occurred in the deafferented adult rat spinal cord, a model where a major reorganization of neural circuits takes place. GABAergic expression following unilateral dorsal rhizotomy was studied by means of non-radioactive in situ hybridization to detect GAD67 mRNA and by immunohistochemistry to detect GAD67 protein and GABA. Three days following rhizotomy the number of GAD67 mRNA-expressing neurons was decreased in the superficial layers of the deafferented horn, while GABA immunostaining of axonal fibres located in this region was highly increased. Seven days after lesion, on the other hand, many GAD67 mRNA-expression neurons were bilaterally detected in deep dorsal and ventral layers, this expression being correlated with the increased detection of GAD67 immunostained somata and with the reduction of GABA immunostaining of axons. GABA immunostaining was frequently found to be associated with reactive astrocytes that exhibited intense immunostaining for glial fibrillary acidic protein (GFAP) but remained GAD67 negative. These results indicate that degeneration of afferent terminals induces a biphasic response of GABAergic spinal neurons located in the dorsal horn and show that many spinal neurons located in deeper regions re-express GAD67, suggesting a possible participation of the local GABAergic system in the reorganization of disturbed spinal networks.     

The intradermal cutaneous suture with separate stitches using a resorbable monofilament (Polyglecaprone 25)

The introduction of sutures using Polyglecaprone 25 (Monocryl--Ethicon SpA) has facilitated the use of intradermal suture with separate stitches owing to its flexibility and softness, with extremely satisfactory aesthetic results. The authors report their experience regarding the use of this new material from May 1995 to April 1996 in 250 cases of intradermal suture with separate stitches. The paper also describes a few technical details and emphasis their advantages.     

Dimensions of the lumbar spinal canal: variations and correlations with somatometric parameters using CT

The aim of this study was to investigate the correlation of vertebral dimensions with somatometric parameters in patients without clinical symptoms and radiological signs of central lumbar spinal stenosis. One hundred patients presenting with low back pain or sciatica were studied with CT. In each of the L3, L4 and L5 vertebra three slices were taken with the following measurements: 1. Slice through the intervertebral disc: (a) spinal canal area; (b) interarticular diameter; (c) interligamentous diameter. 2. Slice below the vertebral arcus: (a) dural sac area; (b) vertebral body area. 3. Pediculolaminar level: (a) anteroposterior diameter and interpedicular diameter of the spinal canal; (b) spinal canal area; (c) width of the lateral recesses. The Jones-Thomson index was also estimated. The results of the present study showed that there is a statistically significant correlation of height, weight and age with various vertebral indices. The conventional, widely accepted, anteroposterior diameter of 11.5 mm of the lumbar spinal canal is independent of somatometric parameters, and it is the only constant measurement for the estimation of lumbar spinal stenosis with a single value. The present study suggests that there are variations of the dimensions of the lumbar spinal canal and correlations with height, weight and age of the patient.     

A case of intrathoracic dumb-bell ganglioneuroma and a surgical approach using spinal evoked potentials (SEP)

A successfully treated case of a seven-year-old girl with a left intrathoracic Dumb-bell ganglioneuroma is reported. The tumor was 10 cm in diameter. Preoperative angiography revealed that the location of tumor was very close to the Adamkiewicz artery. In order to prevent the artery from damaging, spinal evoked potentials (SEP) was used during the surgery and was very useful for monitoring the spinal cord. Although SEP has often been employed in spine surgery, the literature on the use of it for posterior mediastinal tumor is scarce. It is considered that SEP is very useful for not damaging the feeding artery to the spinal cord, and for preventing the postoperative neurologic complications.     

Frequency and severity of panic attack symptoms in a treatment seeking sample of trauma victims

The scientific bases and the peculiarities of the new radiation safety standards (RSS) implemented in Russia in april 1996 are considered. A comparison is made of the merits and shortcomings of both conceptions of standardization--by means of setting dose limits for the critical organs or by means of limiting the effective dose as a measure of the total radiation risk of late effects. The application of the effective dose to practice gives unquestionable advantages for assessing the sufficiency of arrangements providing radiation safety of personnel or public protection against radiation. However the use of the effective dose for individual dose monitoring is often not good (especially in the case of internal irradiation) due to wide variation caused by oversimplifications in the applied models. Essential shortcomings of the RSS-96 are also the absence of the permissible body burden of radionuclides among the derived standards and the regulation of the mean annual (unmeasurable) values of their concentration in air. It is proposed in addition to the effective dose which limits the risk of stochastic effects to reserve in the RSS the limits of equivalent doses for the main body organs (lungs, liver). This would eliminate the deterministic effects and give the possibility of differential evaluation of the irradiation pattern. It is also proposed to replace the reglamentation of mean annual concentrations of radionuclides in air by the reglamentation of their permissible concentration in the working zone.     

Video-assisted lateral intertransverse process arthrodesis. Validation of a new minimally invasive lumbar spinal fusion technique in the rabbit and nonhuman primate (rhesus) models

STUDY DESIGN: Cadaveric anatomic and in vivo survival animal studies were performed to develop a new arthrodesis technique for the lumbar spine. OBJECTIVES: To examine the feasibility, efficacy, and safety of a minimally invasive lumbar intertransverse process arthrodesis technique using an osteoinductive growth factor (rhBMP-2) delivered in a collagen sponge carrier. The technique was first developed using a rabbit model and modified for the nonhuman primate (rhesus monkey), a larger animal with the most similar bone biology to humans. SUMMARY OF BACKGROUND DATA: The morbidity of conventional posterolateral lumbar intertransverse process arthrodesis includes graft donor site morbidity; paraspinal muscle devascularization, denervation, and scarring and nonunion in up to 36% of patients. Minimally invasive anterior lumbar interbody arthrodesis techniques have been developed, but these often require a metal implant and carry risks to major vessels and development of retrograde ejaculation. A minimally invasive technique for posterolateral intertransverse process arthrodesis has not been described previously. METHODS: In Part 1, we examined seven New Zealand white rabbits and five rhesus monkeys at necropsy and during nonsurvival surgeries to determine the best access routes and to develop special instruments for video-assisted lateral intertransverse process arthrodesis. In Part 2, 38 New Zealand white rabbits underwent L4-L5 intertransverse process arthrodesis: the "OPEN" group (n = 16) underwent a standard open muscle-splitting approach using rhBMP-2 (bone morphogenetic protein) and collagen as a bone graft substitute; the "video-assisted control" group (n = 6) underwent video-assisted lateral intertransverse process arthrodesis with the collagen implant only (no growth factor); and the "video-assisted-BMP" group (n = 16) underwent video-assisted lateral intertransverse process arthrodesis with rhBMP-2 and collagen as the graft material. In Part 3, rhesus monkeys (n = 4) underwent video-assisted lateral intertransverse process arthrodesis using rhBMP-2 and collagen after laminectomy of L4-L5. RESULTS: In Part 1, we identified expedient, minimally invasive routes to the intertransverse process interval appropriate for each species: an intermuscular approach for the rabbit and a lateral, extramuscular approach for the rhesus monkey. In Part 2, all rabbits in the OPEN and video-assisted-BMP groups achieved solid intertransverse process lumbar fusions when assessed at 10 weeks. There were no neurologic impairments nor any difference between the two groups in the frequency of postoperative infection or other complications. None of the animals in the video-assisted control group showed evidence of fusion. In Part 3, exposure, decortication and grafting with rh-BMP-2 and collagen was accomplished successfully in all four monkeys through the video-assisted minimally invasive approach without complications. CONCLUSION: Video-assisted lateral intertransverse process arthrodesis is a feasible, effective, and safe method of lumbar spinal fusion in the rabbit and rhesus monkey. Use of this arthrodesis procedure will minimize the morbidity of paraspinal muscle denervation and devascularization seen with open intertransverse process fusion techniques, and the use of an osteoinductive growth factor will eliminate the problem of graft donor site morbidity and possibly increase the chances for successful fusion.     

Frequency of carcinoma in a medium-sized country-hospital (author's transl)

The author tried to give a broad survey of the cases of carcinoma in a medium-sized hospital during a certain period. The research included the following criteria: frequency, distribution regarding sex and age, localisation of carcinoma, histology, therapeutical methods, kind of metastasia and survival time. The 5 most frequent cases of carcinoma were more closely investigated in detail. The importance of a more intensified early diagnosis of carcinoma for keeping the rate of inoperable cases low is stressed.     

Spontaneous spinal epidural hematoma--report of a case (author's transl)

A typical case of spontaneous spinal epidural hematoma was reported. The patient was a 52 year-old male. He suddenly developed severe high back pain followed by complete paraplegia and rectovesical insufficiency. Myelography disclosed epidural mass extending fro Th2 t0 Th4. Laminectomy and removal of hematoma were carried out 4 days after the onset. Post-operative course was uneventful. Four months later he began to walk with the aids and 7 months later he was fully ambulatory and discharged. We analysed 110 cases already reported including our own and obtained the following conclusions. Spontaneous spinal epidural hematoma was 67% and secondary one 33%. The most frequent precipitating factor was usage of anticoagulant followed by trauma and vascular anomaly. There were relatively many case below the age of 15. The level of lesion predominated in thoracic region. Early operation was imperative but even in delayed cases good result could be expected especially in younger patient and those with lumbal lesion.     

Differential phosphorylation of syntaxin and synaptosome-associated protein of 25 kDa (SNAP-25) isoforms

The synaptic plasma membrane proteins syntaxin and synaptosome-associated protein of 25 kDa (SNAP-25) are central participants in synaptic vesicle trafficking and neurotransmitter release. Together with the synaptic vesicle protein synaptobrevin/vesicle-associated membrane protein (VAMP), they serve as receptors for the general membrane trafficking factors N-ethylmaleimide-sensitive factor (NSF) and soluble NSF attachment protein (alpha-SNAP). Consequently, syntaxin, SNAP-25, and VAMP (and their isoforms in other membrane trafficking pathways) have been termed SNAP receptors (SNAREs). Because protein phosphorylation is a common and important mechanism for regulating a variety of cellular processes, including synaptic transmission, we have investigated the ability of syntaxin and SNAP-25 isoforms to serve as substrates for a variety of serine/threonine protein kinases. Syntaxins 1 A and 4 were phosphorylated by casein kinase II, whereas syntaxin 3 and SNAP-25 were phosphorylated by Ca2+- and calmodulin-dependent protein kinase II and cyclic AMP-dependent protein kinase, respectively. The biochemical consequences of SNARE protein phosphorylation included a reduced interaction between SNAP-25 and phosphorylated syntaxin 4 and an enhanced interaction between phosphorylated syntaxin 1A and the synaptic vesicle protein synaptotagmin I, a potential Ca2+ sensor in triggering synaptic vesicle exocytosis. No other effects on the formation of SNARE complexes (comprised of syntaxin, SNAP-25, and VAMP) or interactions involving n-Sec1 or alpha-SNAP were observed. These findings suggest that although phosphorylation does not directly regulate the assembly of the synaptic SNARE complex, it may serve to modulate SNARE complex function through other proteins, including synaptotagmin I.