[Ultrasound directed punctures in neuro-axial regional anesthesia].
Explore the source record for details and available documents.
Anesthesia, Conduction↗
Biomedical subjects
T Grau
Publications and source records attributed to T Grau.
Ultrasound-guided epidural catheter insertion in children.
UNLABELLED: Epidural catheters (EC) are often used in pediatric patients for intraoperative and postoperative pain relief. The small anatomical structures and catheter insertion under general anesthesia make it more difficult to perform EC and to prevent damage. In this study we investigated the use of ultrasound (US) in detecting neuraxial structures during insertion and placement of EC in children. ASA I-II children scheduled for elective surgery under combined general and epidural anesthesia were studied. Patients received balanced anesthesia using sevoflurane, opioids and rocuronium. Before EC insertion US examination in a lateral position was done to visualize and identify neuraxial structures. Quality of visualization and site and depth of structures were recorded. Using a sterile kit to hold the US probe in position and enable the visualization of the neuraxial structures, an epidural cannula was inserted, using the loss of resistance technique, as the EC passed under US control to the desired level. Of 25 children, 23 were evaluated. Epidural space, ligamentum flavum, and dural structures were clearly identified and the depth to skin level estimated in all patients. Loss of resistance was visualized in all patients with a lumbar epidural approach. Correlation of US measured depth and depth of loss of resistance was 0.88. In eight of 23 patients EC could be visualized during insertion and in 11 others it could be visualized with additional US planes. US is an excellent tool to identify neuraxial structures in both infants and children. The size and the incomplete ossification of the vertebra allow exact visualization and localization of the depth of the epidural space, the loss of resistance, and all relevant neuraxial structures. IMPLICATIONS: Epidural catheters in children are mostly inserted under sedation or general anesthesia. This study showed that the use of ultrasound could help visualize all relevant neuraxial structures and their site and depth from the skin.
Analgesia, Epidural↗
Re: central venous catheterization in infants.
Explore the source record for details and available documents.
Catheterization, Central Venous↗
[Survey on practice of regional anaesthesia in Germany, Austria, and Switzerland. Part 1: Quality assurance and training concepts].
The practice of regional anaesthesia in German speaking countries was investigated by a survey. The first part of the trilogy contains the presentation and evaluation of the data about quality assurance and training concepts. In 2002 questionnaires were mailed to 750 randomly selected departments of anaesthesia and 384 hospitals participated (51.2%). The overall proportion of regional anaesthesia was 23% and in Switzerland it was significantly higher (adults: 48%; children: 31%). Of the hospitals 19% had no person who was responsible for quality assurance. The number of puncture attempts was unlimited in 59% of the hospitals. The first training steps were observed closely (complete observation: 81%). The exact beginning (48%) and end (15%/13%) of the training were often not fixed, 80% of all anaesthesia departments requested an improvement in the training for peripheral and 53% for neuroaxial regional anaesthesia techniques. Regional anaesthesia plays a highly important role. Concepts of training and quality assurance that are backed up by evidence-based medicine should be worked out to improve the training and further education in regional anaesthesia.
Adult↗
[Survey on practice of regional anaesthesia in Germany, Austria, and Switzerland. Part 3: Methods in obstetric anaesthesia].
The practice of regional anaesthesia in German speaking countries was investigated by a survey. The last part of the trilogy contains the presentation and evaluation of the data about the methods in obstetric anaesthesia. In 2002 questionnaires were mailed to 750 randomly selected departments of anaesthesia, 384 hospitals (51.2%) responded of which 278 had an obstetric unit. Caesarean section rate was 22.5+/-8.2% and for elective caesarean section spinal anaesthesia was mostly used. General anaesthesia was never used in 58.3% of Swiss, 10.2% of German, and 21.1% of Austrian hospitals. For non-elective caesarean section 42.1% of the hospitals often used a spinal anaesthesia, and 44.8% sometimes, in Switzerland these were 92.9% and 7.1%, respectively. Pain relief for labour was usually achieved with epidural anaesthesia or drugs. The trend from general to regional anaesthesia for caesarean section is continued, as is the trend from local infiltrative techniques to epidural anaesthesia for vaginal delivery. Switzerland was in the forefront for these developments.
Adult↗
[Survey on current practice of regional anaesthesia in Germany, Austria, and Switzerland. Part 2: Use, success rates and techniques].
The current practice of regional anaesthesia in German-speaking countries was investigated in a survey. The second part of the trilogy presents data about its use, success rates, and techniques. In 2002 questionnaires were mailed to 750 randomly selected departments of anaesthesia of which 384 hospitals participated. Peripheral regional anaesthesia is used above all in traumatology and orthopaedics, 45% of the hospitals with paediatric surgery never used neuroaxial blocks. The residents achieved mean success rates of 69.7+/-11.8% for supraclavicular plexus block to 85.5+/-9.0% for spinal anaesthesia, the specialists in anaesthesia 79.2+/-11.3% (supraclavicular plexus block) to 91.0+/-6.8% (spinal anaesthesia). Standards for basic techniques, recording of success rates, and for quality assurance of peripheral nerve blocks should be worked out to improve the application of peripheral regional anaesthesia procedures. In neuroaxial anaesthesia satisfying success rates were reached in German-speaking countries. In paediatric anaesthesia its use still has many opponents.
Adult↗
Real-time ultrasonic observation of combined spinal-epidural anaesthesia.
BACKGROUND AND OBJECTIVE: The quality of combined spinal-epidural anaesthesia mainly depends on accurate identification of the epidural space. The real-time ultrasound control of the procedure for puncture was therefore evaluated. METHODS: Thirty parturients scheduled for Caesarean section were randomized to three equal groups. Ten control patients received conventional combined spinal-epidural anaesthesia. Ten of the remaining patients received ultrasonic scans by an offline scan technique, and 10 received online imaging of the lumbar region during epidural puncture. The epidural space was identified and needle advancement was surveyed through the interspinal and flaval ligaments. The number of attempts to advance the needle to achieve a successful puncture was measured and compared, as well as the number of vertebral interspaces punctured before successful entry into the epidural space. RESULTS: There was no difference between patient characteristics in the three groups. The visualization of the epidural structures and of the needle manipulations was very effective. In the ultrasound group, the reduction in the number of attempts at puncture was significant (P < 0.036). The number of interspaces necessary for puncture was reduced (P < 0.036) in the ultrasound online group compared with controls. The number of spinal needle manipulations was significantly reduced (P < 0.036). CONCLUSIONS: Real-time ultrasonic scanning of the lumbar spine is an easy procedure. It provides an accurate reading of the location of the needle tip and facilitates the performance of combined spinal-epidural anaesthesia.
Adult↗
[Ultrasound and local anaesthesia. Part III: ultrasound and neuroaxial local anaesthesia].
The use of ultrasound as a diagnostic tool for the visualisation of the epidural space has effects on the quality and the performance of epidural anesthesia. This work presents an overview of the recent experiences with ultrasound for epidural anesthesia and on the possibilities for ultrasound imaging techniques. The results of visualisation of the epidural space and its limiting structures obtained by various working groups are presented. We review all presently available data on the prediction of the puncture depth. The various working groups found correlations between predicted and effective puncture depth between 0.79 and 0.98 and the precision of the measurement was 57-7.7 mm. Regarding the prediction of the puncture angle there was a poor correlation ranging between 0.07 and 0.31. The precision between the measured and the punctured angles was found to be 10-13.4 degrees. In all available prospective randomised studies on the puncture effects in the lumbar epidural space, the influence of ultrasound showed a significant reduction ( p<0.03) of the puncture attempts,and we found a significant ( p<0.05) reduction in the number of puncture levels. The ultrasound-guided puncture allowed an ideal needle trajectory and a more precise application of the catheter. A significant improvement of analgesia quality ( p<0.035) and patient satisfaction ( p<0.006) could be achieved. The metaanalysis of the different studies regarding puncture quality by ultrasound-guided peridural anaesthesia showed a clear advantage for the use of imaging techniques.
Anesthesia, Epidural↗
[Ultrasound in local anaesthesia. Part I: technical developments and background].
The localisation of the nerve to be blocked is one of the special challenges in local anaesthesia. Since the first time local anaesthesia procedures were carried out approximately 100 years ago, the basic limitations of this method have always been the unsatisfactory success rate and the specific risks involved. Even by variation of the access route to the various nerves and use of different identification methods, no ideal blockade technique has been found which allows a 100% success rate and at the same time reduces the risks to a minimum. The clinical introduction of various aids, such as nerve stimulation or Doppler sonography, have brought no statistically significant advantages despite showing clear improvements. In recent years there has been a trend towards local anaesthesia in perioperative care due to the proven advantages and range of possibilities. Several working groups have developed methods for the sonographic identification of nerves or the epidural space and to an exact placing of needles or catheters from the information obtained. In this way the application of catheters and the injection of local anaesthetic agents can be carried out in an accurate and controlled manner. Although sonography is a procedure which has been used in local anaesthesia for over 10 years, there are at present only few practising local anaesthetists who can use this method. However, interest in this method is growing especially due to the aspect of quality assurance. Organising committees have established that this method will be the future direction. Perhaps even the prediction of Alon P. Winnie for ultrasound-guided local anaesthesia will become true: "Sooner or later someone will make a sufficiently close examination of the anatomy involved, so that exact techniques will be developed."
Anesthesia, Conduction↗
[The visualisation of dura perforation and blood patches with ultrasound].
The postdural puncture headache (PDPH) is a possible complication after spinal or epidural puncture. The therapeutic concept is usually organised step by step, but the epidural blood patch is the most reliable and effective therapy. In earlier studies myelographie, epidurographie and MRT were used, to visualise the localisation of the dural defect and to describe the effects of patching the epidural space. Our working group focused on the utilisation of ultrasound and we decided to use this technique for the visualisation of bloodpatches. With agreement of the local ethics committee we monitored the performance of 4 epidural bloodpatches in pregnant women, who suffered from PDPH. We used a General Electric LQ 400 ultrasonograph with a 7-MHz-probe. To ensure sterile conditions we used sterile ultrasound sleeves and sterile ultrasound gel. In 3 of 4 cases a continuity loss could be represented in the doppel layer signal of the dura. It had the size of the diameter of a Tuohy needle. In one case the defect of the dura was larger than in the preliminary investigations (2,5 - 3 mm). The ultrasonography of the epidural space was performed in the paramedian scan. All patches were placed by using the conventional loss of resistance technique with using online ultrasound support. The epidural puncture and the application of the blood patches were visualised simultaneously in all cases. With the injection of blood a brief expansion of the epidural space was seen. The patients recieved a mean injection volume of 17 ml sterile blood. 10 to 40 seconds after the injection of blood the disconituity of the dura doppel layer signal was no longer provable. Within a short time we could detect the increase of cerebrospinal fluid and the patients headache was treated sucessfully. The clinical use of this diagnostic technique can be found in the simultaneous presentation of the dura leakage and the intervention while performing an epidural bloodpatch. Since these informations are relevant for further clinical practice further investigations are warranted.
Adult↗
[Ultrasonography and peridural anesthesia. Technical possibilities and limitations of ultrasonic examination of the epidural space].
Epidural anaesthesia (EA) is the most important analgesia technique in obstetrics for delivery. In pregnancy, hormonal adjustments lead to an alteration of tissue consistency, which often causes an early, untimely loss of resistance. Apart from mere inspection and palpation, no useful diagnostic method prior to EA performance has been established yet. In this prospective study, we examined 100 pregnant women, who had been admitted for childbirth and were undergoing epidural block (level L3-L4) for delivery. Sonotopography of the lumbar epidural structures was performed directly before epidural puncture and childbirth. We evaluated the visibility of all anatomical structures and compared all distances measured by ultrasonography and during puncture. The correlation between distances measured by ultrasound and by puncture needle was high (r2 = 0.79). No obvious dependency was found between ultrasonic and puncture angle (r2 = 0.19). The temporal distance from ultrasonic examination and puncture causes unavoidable differences: each deviation between ultrasound and puncture conditions causes a modification of the puncture depth. The patient acceptance of the procedure was very good. Ultrasonography offers the possibility to determine site and direction of epidural puncture and distance of the epidural space to the skin even before the puncture attempt. The ultrasound controlled EA for delivery can easily be inserted into the clinical routine. Ultrasonography can fill an important diagnostic gap in regional anaesthesia.
Adult↗
Paramedian access to the epidural space: the optimum window for ultrasound imaging.
STUDY OBJECTIVE: To establish a useful ultrasonic approach to the epidural space so as to optimize pre-puncture diagnostics. DESIGN: Prospective study. SETTING: University clinic. PATIENTS: 60 participants (19 to 34 years of age), 40 healthy volunteers (20 male, 20 female) and 20 parturients. INTERVENTIONS: Ultrasound scanning of the lumbar spine was performed at the L(3)-L(4) vertebral interspace. Three ultrasound planes were employed: the transverse, median, and paramedian longitudinal approaches. MEASUREMENTS: We compared the width of the ultrasound-permeable area in the median and paramedian planes and assessed the visibility of the epidural space and its surrounding structures. MAIN RESULTS: In the paramedian plane, the permeable window was larger (p < 0.001) than in the median approach. The visibility of the ligamentum flavum (p < 0.0001), dura mater (p < 0.0001), and cauda equina (p < 0.0001) was significantly higher. Pulsation of epidural vessels could be observed more frequently (p < 0.0001) in the paramedian plane. CONCLUSIONS: The longitudinal paramedian plane provided information about the epidural space depth in excellent imaging quality. The additional information might be beneficial in epidural anesthesia and in other clinical specialties (e.g., neurosurgery, trauma care).
Adult↗
Ultrasound control for presumed difficult epidural puncture.
BACKGROUND: The efficacy of epidural anaesthesia depends on the accurate identification of the epidural space (ES). Abnormal anatomical conditions may make the procedure difficult or impossible. The aim of this study was to investigate whether pre-puncture ultrasound examination of the spinal anatomy might be beneficial in expected cases of difficult epidural anaesthesia. METHODS: We used digital ultrasound equipment with a 5-MHz transducer to assess the anatomy of the ES and the posterior parts of the spinal column. We examined 72 parturients with abnormal anatomical conditions who were scheduled for epidural anaesthesia. The women were randomised into two equal groups. In all patients, the standard loss of resistance technique was used. In the ultrasound group, an ultrasound examination of the appropriate spinal region was conducted prior to epidural puncture. ES depth seen on the ultrasound images was compared to the ES depth measured by the needle. We compared the number of puncture attempts with the standard method (control group) to the number of attempts under ultrasound guidance. RESULTS: Ultrasonography significantly improved operating conditions for epidural anaesthesia. The maximum VAS scores and patient acceptance were significantly better. CONCLUSIONS: With ultrasound measurement of the ES depth, the quality of epidural anaesthesia was enhanced.
Adult↗
Colour Doppler imaging of the interspinous and epidural space.
BACKGROUND AND OBJECTIVE: In recent studies, ultrasonic diagnostic imaging has proved useful in the screening of the trajectory of the epidural needle. With regard to possible side-effects of spinal and epidural anaesthesia caused by vessel injury, we aimed to evaluate the usability of Colour Doppler imaging for the depiction of interspinous vessels in prepuncture examination. METHODS: Ultrasonic examination of the L3/4 interspace area was performed in 20 volunteers. Using a 4-MHz and a 7-MHz probe with B-mode and Colour Doppler imaging, respectively, we compared four settings for the quality of vessel depiction in the puncture area. Overall resolution was evaluated according to the distinction of landmarks. Vascular structures were identified by pulsation (B-mode) or blood flow (Doppler). RESULTS: Colour Doppler imaging of the L3/4 interspace was unachievable using the 7-MHz transducer. Vessel detection was possible in 50% of the B-mode images and in all of the 4-MHz Doppler images. Vessels were perceptible from a diameter of 0.5 mm. Veins were the predominantly visible structures. Overall vessel visibility was best using 4-MHz Colour Doppler. CONCLUSIONS: Prepuncture Doppler imaging can provide the epiduralist with information regarding the position of vessels in the needle trajectory. This might help to reduce complications in regional anaesthesia.
Adult↗
The lumbar epidural space in pregnancy: visualization by ultrasonography.
Epidural anaesthesia is an important analgesia technique for obstetric delivery. During pregnancy, however, obesity and oedema frequently obscure anatomical landmarks. Using ultrasonography, we investigated the influence of these changes on spinal and epidural anatomy. We examined 53 pregnant women who were to receive epidural block for vaginal delivery or Caesarean section. The first ultrasound imaging was performed immediately before epidural puncture; the follow-up scan was done 9 months later. The ultrasound scan of the spinal column was performed at the L3/4 interspace in transverse and longitudinal planes, using a Sonoace 6000 ultrasonograph (Kretz, Marl, Germany) equipped with a 5.0-MHz curved array probe. We measured two distances from the skin to the epidural space: the minimum (perpendicular) and the maximum (oblique) needle trajectory. The quality of ultrasonic depiction was analysed by a numerical scoring system. An average weight reduction of 12.5 kg had occurred by the follow-up examination. During pregnancy, the optimum puncture site available on the skin for epidural space cannulation was smaller, the soft-tissue channel between the spinal processes was narrower, and the skin-epidural space distance was greater. The epidural space was narrower and deformed by the tissue changes. The visibility of the ligamentum flavum, of the dura mater and of the epidural space decreased significantly during pregnancy. Nevertheless, ultrasonography offered useful pre-puncture information. Thus far, palpation has been the only available technique to facilitate epidural puncture. Ultrasound imaging enabled us to assess the structures to be perforated. We anticipate that this technique will become valuable clinically.
Adult↗
[Pre-eclampsia and anesthesia].
The management of anaesthesia in patients suffering preeclampsia has to be selected individually. There is a high rate of caesarean sections in patients with preeclampsia. Intubation anaesthesia or regional anaesthesia are commonly used methods and can be considered comparable and equally useful. In our opinion, the application of regional anaesthesia should be preferred, if the initial criteria, such as normal neurologic status and blood coagulation, are fulfilled. We believe in a considerable reduction of vital risks when using regional anaesthesia. Our aim was to figure out the risk-factors of preeclampsia and preterm maturity regarding anaesthesia management. Preeclampsia is a severe illness in pregnancy with a frequency of 5-10%. In 1997, we experienced 73 patients with praeeclampsia according to the definition of ISSPH. Mode of delivery was conventional in 10 patients, 2 patients had a vacuum extraction and 61 patients needed a caesarean section. The rate of epidural anesthesia for delivery was 51%. We used epidural anaesthesia in 6 spontaneous deliveries, in 2 vacuum extractions and in 30 caesarean sections. There were no problems with epidural anaesthesia and the outcome of mother and child was also considered to be excellent. We suggest to use regional anesthesia techniques whenever possible.
Anesthesia, Conduction↗
[A needle-free intraoral injection technic. Clinical study of patient acceptance of the Syrijet Mark II Needleless Injector (Mizzi, Inc., N.J., U.S.A.)].
Explore the source record for details and available documents.
Adolescent↗
Uptake and phototoxic effects of aluminum-chlorophthalocyanine (AlSPc) in human bladder carcinoma cells.
In vitro experiments were performed on human bladder carcinoma cells to evaluate the uptake of aluminum-chlorophthalocyanine (AISPc) and the subcellular target of phototoxicity. In order to quantify the correlation of intracellular uptake and incubation time and to identify the primary subcellular target of phototoxicity, fluorescence and absorption measurements have been carried out as well as electron microscopic studies. Absorption and fluorescence measurements showed the largest value after 24 h of incubation time. Fluorescence microscopic studies suggested the sensitizer to be located in a brighter patch within cytoplasm. Electron microscopic studies using DAB (3,3' diaminobenzidine) staining showed that the mitochondria are the primary target of phototoxic activity of AlSPc and that the majority of vacuoles of treated cells were originally mitochondria.
Carcinoma, Transitional Cell↗