Local Anaesthetic (local + anaesthetic)

Distribution by Scientific Domains
Distribution within Medical Sciences

Terms modified by Local Anaesthetic

  • local anaesthetic agent
  • local anaesthetic injection
  • local anaesthetic solution

  • Selected Abstracts

    Synthesis of N-Substituted-N-acylthioureas of 4-Substituted Piperazines Endowed with Local Anaesthetic, Antihyperlipidemic, Antiproliferative Activities and Antiarrythmic, Analgesic, Antiaggregating Actions.

    CHEMINFORM, Issue 2 2004
    Angelo Ranise
    Abstract For Abstract see ChemInform Abstract in Full Text. [source]

    Hypersensitivity to local anaesthetics , update and proposal of evaluation algorithm

    CONTACT DERMATITIS, Issue 2 2008
    Jacob Pontoppidan Thyssen
    Local anaesthetics (LA) are widely used drugs. Adverse reactions are rare but may be caused by delayed-type hypersensitivity reactions and probably also immediate-type reactions. As it is not always easy to clinically differ between these subtypes, allergy skin testing should be considered. Although numerous test protocols have been published, how patients with hypersensitivity reactions to LA are ideally evaluated remains a topic of discussion. This review attempts to generate a comprehensive update on allergic reactions to LA and to present an algorithm that can be used for the evaluation of patients suspected with immediate- and delayed-type immune reactions. Literature was examined using PubMed-Medline, EMBASE, Biosis and Science Citation Index. Based on the literature, the proposed algorithm may safely and rapidly distinguish between immediate-type and delayed-type allergic immune reactions. [source]

    Suspected allergy to local anaesthetics: follow-up in 135 cases

    Background: Local anaesthetics (LA) are generally considered safe with respect to allergy. However, various clinical reactions steadily occur. Even though most reactions are manifestations of reflexes to perceptive stimuli, uncertainty often remains regarding a possible allergic mechanism. This uncertainty later leads to an avoidance of local anaesthesia and unnecessarily painful interventions, resource-consuming general anaesthesia or even the risk of re-exposure to other yet unidentified allergens. In the present study, follow-up procedures at an allergy clinic were analysed to examine the frequency of identified causative agents and pathogenetic mechanisms and evaluate the strength of the diagnostic conclusions. Method: The medical records of 135 cases with alleged allergic reactions to LA were reviewed. Diagnoses were based on case histories, skin tests, subcutaneous challenge tests and in vitro IgE analyses. Results: Two events (1.5%) were diagnosed as hypersensitivity to LA, articaine,adrenaline and tetracaine,adrenaline, respectively. Ten reactions (7%) were diagnosed as IgE-mediated allergy to other substances including chlorhexidine, latex, triamcinolone and possibly hexaminolevulinate. As challenge testing was not consistently performed with the culprit LA compound, follow-ups were short of definitely refuting hypersensitivity in 61% of the cases. The reported clinical manifestations were in general diagnostically unspecific, but itch and generalised urticaria were most frequent in test-positive cases. Conclusion: Reactions during local anaesthesia are rarely found to be an IgE-mediated LA allergy. Whenever the clinical picture is compatible with allergy, other allergens should also be tested. [source]

    Local anaesthetics and adjuvants , future developments

    ANAESTHESIA, Issue 2010
    M. D. Wiles
    Summary The introduction of local anaesthesia some years after the first public demonstration of general anaesthesia not surprisingly created less excitement and interest amongst both the public and the medical profession. However, in its own way, a new revolution was happening. Local anaesthesia produced an increase in the choice of anaesthetic techniques available to practitioners and patients. In common with general anaesthesia, the choice of agents remained very limited for the first six decades, and interest in the practice of local, regional or central neuraxial blockade and the development of new techniques and drugs were hampered by perceived safety issues even as late as the second half of the 20th century. It is only in the last few years that, with an apparent renaissance in the use of local anaesthesia, the pace of development has picked up. As the use and range of techniques has increased, so has interest in solving some of the longstanding problems with the available drugs. [source]

    1222: Pharmacological overview of the ophthalmic anaesthesia

    Purpose Review of the chemical properties, differences between the effectiveness of the ophthalmological used local anaesthetics. Historical overview from 1860, year of the isolation of cocaine, to date. Methods Didactic and substantive summary of the literature. Results Specification of the basicity, lipophilicity, physicochemical properties, and the advantages, and disadvantages of adding adrenalin in different concentrations. Local anaesthetics also have adverse effects. All stimulate central nervous system, therefore it is very important to have a proper anamnesis, especially information about drug hypersensitivity from the patient. Conclusion Interventions must be carried out in the view of drug interactions, with personalized choice of drugs and dose. [source]

    The Neurogenic Vasodilator Response to Endothelin-1: A Study in Human Skin In Vivo

    Ruwani Katugampola
    We have investigated the mediators and mechanisms underlying the vasodilator effects of the potent vasoactive peptide, endothelin-1 (ET-1) and its isomers ET-2 and ET-3 in human skin, in vivo, using cutaneous microdialysis to quantify the release of mediators within the dermal response and scanning laser Doppler imaging to measure changes in blood flux. The effects of local anaesthesia, inhibition of nitric oxide synthase (NOS) by L-NAME and ET receptor blockade on the ET-induced vascular response were also investigated. ET-1, -2 and -3 all caused a dose-dependent area of pallor surrounded by a long-lasting flare which was accompanied by a short-lived burning pruritus. The concentration of nitric oxide (NO) in dialysate collected within the pallor response to 5 ,M ET-1 (1.43 ± 0.64 ,M, n = 5) was not significantly different from baseline levels collected prior to injection (0.86 ± 0.38 ,M) whilst that in the flare increased to reach a peak value of 2.28 ± 0.61 ,M at between 4 and 10 min after intradermal injection (P < 0.004). Pretreatment with local anaesthetic slowed the development of the flare and significantly reduced its size by up to 52% at 20 min after injection (P < 0.05) but had no significant effect on the central pallor. L-NAME, delivered by dialysis also caused a significant reduction in the ET-1-induced flare (P < 0.005). Bosentan, the non-selective ETA/ETB antagonist, when given by dialysis at the site of injection, reduced the area of both the ET-1-induced pallor and surrounding flare by 41 and 26%, respectively. No significant increase in tissue histamine was measured within either the pallor or flare response to ET-1, -2 or -3. Together these data confirm that the vasodilator response to endothelin-1 in human skin is neurogenic in origin and that it is in part mediated by the local release of nitric oxide. There appears to be little evidence for the involvement of mast cell-derived histamine in the initiation or modulation of ET-induced vasodilatation, in vivo. [source]

    Electrical activation of common bile duct nerves modulates sphincter of Oddi motility in the Australian possum

    HPB, Issue 4 2005
    Y. Sonoda
    Abstract Background: Sphincter of Oddi (SO) motility is regulated by extrinsic and intrinsic nerves. The existence of neural circuits between the SO and the proximal extrahepatic biliary tree has been reported, but they are poorly understood. Using electrical field stimulation (EFS), we determined if a neural circuit exists between the common bile duct (CBD) and the SO in anaesthetized Australian brush-tailed possums. Methods: The gallbladder, cystic duct or CBD were subjected to EFS with a stimulating electrode. Spontaneous SO phasic waves were measured by manometry. Results: EFS at sites on the distal CBD (12,20 mm proximal to the SO), but less commonly at more proximal CBD, evoked a variety of responses consisting of an excitatory and/or inhibitory phase. Bi-phasic responses consisting of an excitation followed by inhibition were the most common. Tri-phasic responses were also observed as well as excitation or inhibition only. These evoked responses were blocked by topical application of local anaesthetic to the distal CBD or transection of the CBD. EFS at sites on the gallbladder body, neck or cystic duct did not consistently evoke an SO response. Pretreatment with atropine or guanethidine reduced the magnitude of the evoked response by about 50% (p<0.05), pretreatment with hexamethonium had no consistent effect and pretreatment with a nitric oxide synthase inhibitor increased the response. Discussion: A neural circuit(s) between the SO and the distal CBD modulates SO motility. Damage to this area of the CBD during bile duct exploration surgery could adversely affect SO motility. [source]

    Testing whether the epidural works: too time consuming?

    Background: When using epidural anaesthesia (EDA) for pain relief after major surgery, a failure rate of 10% is common. A crucial step in improving the care of patients with EDA is to define the position of the epidural catheter. The aim of this study was to investigate how much time it takes to determine whether the block is sufficient by assessing the extent of loss of cold sensation before induction of anaesthesia. Methods: One hundred patients listed for abdominal surgery were included in the study. After an epidural catheter had been inserted and an intrathecal or an intravenous position had been made unlikely by the use of a test dose, the patient was given a bolus dose of local anaesthetic plus an opioid in the epidural catheter. The epidural block was tested every 2 min, starting at 5 min and ending at 15 min. When at least four segments were blocked bilaterally, the testing was stopped, the time was noted and the patient was anaesthetised. Results: An epidural block was demonstrated after 5,6 min in 37 patients, after 7,8 min in 43 additional patients and after 9,10 min in 15 patients. In one patient, it took 12 min and in three patients, it took 15 min. In two patients, no epidural block could be demonstrated. Conclusion: Testing an epidural anaesthetic before the induction of anaesthesia takes only 5,10 extra minutes. Knowing whether the catheter is correctly placed means better quality of care, giving the anaesthetist better prerequisites for taking care of the patient post-operatively. [source]

    Oral myofibromatosis: an unusual cause of gingival overgrowth

    Case report, review of the literature
    Abstract Background:, This case report describes a rare benign tumour, which presented as discrete areas of gingival hyperplasia affecting both the mandible and the maxilla. Method:, Surgical excision of the lesions was carried out under local anaesthetic. Histopathological examination confirmed the diagnosis of oral myofibromatosis. Results: The condition responded to surgical excision and appears to have limited growth potential. It affects a wide spectrum of ages and can be alarming due to rapid enlargement and ulceration, so careful diagnosis is important to avoid unnecessary aggressive treatment. Zusammenfassung Orale Myofibromatose: eine ungewöhnliche Ursache einer gingivalen HyperplasieFallbericht und Literaturüberblick Hintergründe: In dem vorliegenden Fallbericht wird ein seltener benigner Tumor, der sich als klar abgegrenzte Bereiche einer gingivalen Hyperplasie darstellte und durch den sowohl Mandibula als auch Maxilla betroffen waren, beschrieben. Methodik: Unter lokaler Betäubung wurde eine operative Exzision der Läsionen vorgenommen. Eine histopathologische Untersuchung bestätigte die Diagnose einer oralen Myofibromatose. Ergebnisse: Die Erkrankung sprach auf die operative Exzision an und scheint lediglich über begrenztes Wachstumspotential zu verfügen. Eine breites Spektrum an Altergruppen ist betroffen und die Störung kann aufgrund einer rapiden Vergrösserung und Ulzerierung alarmierend sein. Um unnötige aggressive Therapien zu vermeiden ist eine sorgfältige Diagnose erforderlich. Résumé Myofibromatose buccale : une cause inhabituelle d'hypertrophie gingivale. Rapport d'un cas et revue de la littérature Les myofibromatoses sont des néoplasmes bénins rares qui peuvent se présenter soit de maničre solitaire soit en lésions multiples. Un diagnostic attentif de cette tumeur bénigne est important pour éviter une thérapie aggressive non-nécessaire. Avec un traitement chirurgical conservateur, le pronostic est excellent. [source]

    Analgesia for labour: a survey of Norwegian practice , with a focus on parenteral opioids

    T. O. TVEIT
    Background: During the last two decades, epidural analgesia has become ,a gold standard' for labour pain in most Western countries. Newer short-acting opioids given systemically represent an alternative for adequate pain relief without using regional techniques. With this survey, we wish to explore how Norwegian hospitals practice labour analgesia, especially their use of systemic opioids. Methods: A questionnaire was sent to the head of all 46 registered Norwegian labour units in 2005. The questionnaire focused on epidural and the use of systemic opioids. In 2008, the same questionnaire was sent to the 19 largest units reporting >1000 births a year, seeking updated information. Results: Forty-three of the 46 original questionnaires were returned. An epidural frequency of 25.9% was registered. For epidural treatment, bupivacaine was the preferred local anaesthetic, while sufentanil was the opioid of choice for the majority of units. Pethidine was the most commonly used opioid for systemic administration (77%). All units reported nurse administration of systemic opioids. The intramuscular route was most commonly used, either alone (58%) or in combination with an intravenous (i.v.) administration (34%). Only one unit used i.v. fentanyl. There were only minor changes with the repeated survey, except for one large unit, which reported over a 50% increase in the epidural frequency. Conclusion: In Norway, the frequency of epidural for labour analgesia is still relatively low, but seems to be increasing. Systemic opioids are often used instead of or as a supplement. Clinical practice seems to be conservative, and newer short-acting opioids are seldom used systemically. [source]

    The role of cutaneous sensation in the motor function of the hand

    Ayman M. Ebied
    Abstract We studied the effect of abolishing cutaneous sensation (by infiltrating local anaesthetic around the median nerve at the wrist) on the ability of 10 healthy volunteers (a) to maintain a submaximal isometric pinch-grip force for 30 s without visual feedback, and (b) to perform a fine finger-manipulation ,handwriting" task. Blocking cutaneous sensation had no effect on ability to maintain pinch force, suggesting that muscle afferents have the major role in force-control feedback. However, a near-linear fall in force, present with or without block (mean slope = ,1.3 ± 0.2% s,1), which cannot be attributed to motor fatigue, reveals a shortcoming of the afferent feedback system. Blocking cutaneous sensation did impair ability to perform the more demanding writing task, as judged by an 18 ± 6% increase in the length of the path between target points, a 22 ± 9% increase in the duration of the movement and a 63 ± 24% in ,normalised averaged rectified jerk", an averaged time-derivative of acceleration (all significantly nonzero, P < 0.04). These experiments demonstrate the relative importance of muscular and cutaneous afferent feedback on two aspects of hand performance, and provide a way to quantify the deficit resulting from the lack of cutaneous sensation. © 2003 Published by Elsevier Ltd. on behalf of Orthopaedic Research Society. All rights reserved. [source]

    Iatrogenic injury in childhood staphylococcal scalded skin syndrome

    SA Holme
    Abstract: Staphylococcal scalded skin syndrome (SSSS) may cause significant morbidity in children. It is common practice for adhesive occlusive dressings to be used to apply topical local anaesthetic prior to venepuncture. We report two cases in which removal of these dressings from children with SSSS caused injury and discomfort in areas previously free from blistering. We recommend that an alternative method of topical anaesthetic application is used to minimize skin trauma in these patients. [source]

    In-vitro release of bupivacaine from injectable lipid formulations investigated by a single drop technique , relation to duration of action in-vivo

    Lars Söderberg
    The aim of this study was to develop an in-vitro release method suitable for injectable slow-release lipid formulations of local anaesthetics (or other drugs). We also aimed that the results of the in-vitro measurements should have a clear relationship to duration of action in-vivo. Six formulations of bupivacaine base in medium-chain triglyceride-glyceryl dilaurate mixtures were developed. A new apparatus was constructed for determination of their in-vitro release profiles. A bulbous glass tube was fixed inside a standard glass bottle, which was then filled with release medium. A stirring magnet was enclosed in the perforated polypropylene cylinder holding the glass tube. The stirring created a continuous, rotating downward flow of medium inside the tube, which kept the lipid phase, introduced by means of a syringe, suspended as a single, free drop. Release profiles were obtained by sampling of the release medium for up to 72 h and analysis by gas-liquid chromatography. The duration of action in-vivo of the respective formulations was tested by the hot-plate method in rats. The release profiles of bupivacaine in-vitro were mono-exponential for four formulations and bi-exponential for the other two. There was a positive correlation between the proportion of glyceryl dilaurate in the formulation and the slow half-life of release of bupivacaine. All formulations showed prolonged duration of action in-vivo, median values within the range 4.5,12 h, as compared with a 2-h effect of bupivacaine hydrochloride solution. A comparison of in-vitro release curves and durations of action in-vivo suggested that to maintain nerve blockade in-vivo the formulations must release bupivacaine at a rate of approximately 350 ,g h,1 under the in-vitro conditions. To conclude, we designed and tested a novel apparatus for measuring release of a local anaesthetic (or other drug) from a fluid or semi-solid formulation in-vitro. Release rates obtained in-vitro by means of this technique may be used to guide the development of formulations with suitable durations of action in-vivo. The apparatus is, however, as yet a prototype. Rigorous evaluation of performance should be carried out on devices built to specific standards according to their intended application. [source]

    Anaesthetic choice for palatal canine exposure

    ORAL SURGERY, Issue 1-2 2010
    S. Hetherington
    Abstract Aim:, To determine if predicted difficulty of exposure of palatally displaced, unerupted canines assessed by radiographic score had influenced the choice between a local or a general anaesthetic procedure in adolescents. Materials and methods:, This was a retrospective analysis of patients undergoing surgical exposure of palatal canines between December 2005 and June 2008 in a dental hospital setting. A total of 56 subjects, for whom complete records were available, aged 16 years or under and assessed and treated by one surgeon, were included. The predicted degree of difficulty of exposure was graded from preoperative radiographs based on three criteria; the horizontal and vertical position of the crown, and the canine angulation (possible score range 3,11: higher score = more difficulty). The radiographic scores and patient age for the local anaesthetic and general anaesthetic groups were compared using Student's unpaired t -tests. Other variables including gender, other surgical treatment required and unilateral or bilateral exposure were evaluated by chi-squared analysis. Results:, Thirty-one (55%) patients were treated with local anaesthetic and 25 (45%) with general anaesthetic, the mean age was 13.7 years. The mean radiographic scores did not differ between groups being 7.53 and 7.36 for the local anaesthetic and general anaesthetic groups, respectively. Chi-squared analysis showed concurrent other surgical treatment to be the only statistically significant factor in anaesthetic choice. Conclusions:, Difficulty of canine exposure is not a significant factor in anaesthetic choice for adolescents, other concurrent surgical treatment appears a more significant factor in anaesthetic choice in this group. [source]

    A comparison of coracoid and axillary approaches to the brachial plexus

    Z. J. Koscielniak-Nielsen
    Background: Brachial plexus block by the coracoid approach does not require arm abduction and may be more effective than the axillary approach because of a more proximal injection of local anaesthetic. However, the clinical usefulness of the coracoid approach has not been tested in prospective controlled trials. The present randomized, observer-blinded study compared success rates, time to obtain a complete block, frequency of adverse effects and block discomfort in two groups of 30 patients, anaesthetized for hand surgery using either the coracoid or the axillary approach to the brachial plexus. Methods: After subcutaneous infiltration with 5 ml of 1% mepivacaine/adrenaline the brachial plexus was located using a nerve stimulator and an insulated pencil-point needle. Ropivacaine 0.75%, 20,40 ml, depending on body weight, was used for the initial block. In the coracoid (C) group two plexus cords, and in the axillary (A) group four terminal nerves were electrolocated and the volume of ropivacaine was divided equally between them. Spread of analgesia to the arm was assessed every 5 min, by an anaesthetist unaware of the block technique. The block was defined as effective (complete) when analgesia was present in all five sensory nerve areas distal to the elbow. Incomplete blocks were supplemented 30 min after the initial block. Results: In the C group a median 11 min was required for block performance as compared to 12 min in the A group (NS). Onset of block was shorter and the frequency of incomplete blocks lower in the A group (median 17 min and 17%) than in the C group (30 min and 47%, respectively). Lack of analgesia of the ulnar nerve was the main cause of incomplete initial blocks in the C group. All incomplete blocks were successfully supplemented. However, total time to obtain complete block was shorter in the A group than in the C group (29 min vs. 41 min, P<0.05). Accidental arterial puncture occurred in seven patients (five in C and two in A group), which resulted in two haematomas, both in the C group (NS). No permanent sequelae were observed. Conclusion: The axillary approach to the brachial plexus using four injections of ropivacaine results in a faster onset of block and a better spread of analgesia than the coracoid approach using two injections. [source]

    Spread of local anaesthetic solution in epidural space visualisation with ultrasound in single shot caudals

    K. Raghavan
    Background:, Ultrasonography is becoming an important adjunct in paediatric neuraxial blockade. Ultrasound guidance helps in visualisation of relevant neuraxial structures, predicting depth of epidural space from skin, reduction in bony contact and faster epidural placement. The visibility of neuraxial structures declines in patients as age increases. To date, there are no studies looking at the extent of spread of local anaesthetic solution in the epidural space and its correlation to the volume used, under ultrasound guidance. We report the results of our audit on spread of local anaesthetic solution in the epidural space in single shot caudal blocks. This abstract is based on the first 17 patients, the presentation will be based on all 50 patients. Methods:, This audit was approved by the local audit committee. We aimed to follow the extent of the spread of local anaesthetic within the epidural space with real time ultrasonography. Patients were selected when the planned anaesthetic included a single shot caudal block. The anaesthetists performing the anaesthetic and the caudal block consented to our ultrasound visualisation. All patients were below 5 years of age. No attempt was made to standardise the technique, the dose, or the speed of injection. After the placement of the caudal cannula by the primary anaesthetist involved in patient care, a separate anaesthetist, experienced in using ultrasound, visualised the neuraxial structures and subsequent spread of the local anaesthetic solution with real time ultrasound. The spread was followed during the injection and for 10 s after the completion of the injection. A 5 cm 7.5,12 MHz linear array was used longitudinally with either midline or paramedian approach. Results:, We are reporting the preliminary results from 17 patients. Patients were aged between 1 day and 1 year 10 months. They weighed between 3.3 kg and 14.6 kg. Either 22 gauge Jelco or Abbocath were used to perform the procedure; 0.25% or 0.20% L-bupivacaine was used on all occasions. The volume administered per kg ranged between 0.33 and 1.27 ml. The visibility of neuraxial structures was good on all occasions. On calculating the Spearmans correlation coefficient, the extent of spread of local anaesthetic in the epidural space was positively correlated with the volume used by a correlation coefficient of 0.64, with a P value of 0.008. The postoperative pain score in recovery was 0 in 16 out of the 17 cases. The one failure occurred when the observed spread would not have been expected to provide analgesia for the performed operation. Conclusions:, Among children below 5 years of age, there seems to be a positive correlation between the volume of local anaesthetic injected into the epidural space and the extent of its spread. This needs to be further investigated by a prospective randomised control trial. The utility of real time ultrasound to allow a reliable achievement of a desired level of sensory block, should be investigated i.e, whether the volume used in achieving a desired level of local anaesthetic spread, as guided by ultrasound, provides superior analgesia and fewer adverse effects compared with the volume calculated using the Armitage regimen. References, 1,Rapp HJ, Folger A, Grau T. Ultrasound guided epidural catheter insertion in children. Anesth Analg 2005; 101: 333,339. 2,Willschke H, Marhofer P, Bosenberg A, et al. Epidural catheter placement in children: comparing a novel approach using ultrasound guidance and a standard loss of resistance technique. Br J Anaesth 2006; 97: 200,207. 3,Marhofer P, Bosenberg A, Sitzwohl C et al. Pilot study of neuraxial imaging by ultrasound in infants and children. Pediatr Anesth 2005; 15: 671,676. [source]

    The BCH Epidural System, a safe system for epidural infusion analgesia in children

    N. Llewellyn
    Epidural infusions in children are usually delivered by syringe drivers because of the lower volumes of local anaesthetic solutions used in children rather than in adult practice. Recently concern has arisen both via the media and anecdotally over a number of adverse events associated with intravenous administration of bupivacaine. We have designed and validated a system that should significantly reduce the possibility and incidence of this adverse effect. (1) [ The system is based on the reversal of the standard luer-lock system. ] A female 60 cc syringe is connected to a reversed 150 cm infusion line that is connected to a male epidural filter. The filter connects with standard epidural infusion catheters. The reversal of the luer-lock system requires that devices are also available for the initial doses of local anaesthetic, for the preparation of the epidural infusion syringe and for administration of rescue boluses of local anaesthetic. With this system it is extremely unlikely that the epidural syringe or infusion catheter can be connected to an intravenous line. It is also less likely that intravenous drugs may be connected to the epidural filter. [source]

    Infusions of local anaesthetic via caudal catheters in neonates and small infants for analgesia after major surgery

    A. Moriarty
    No abstract is available for this article. [source]

    Analgesic efficacy of local anaesthetic wound administration in knee arthroplasty: volume vs concentration

    ANAESTHESIA, Issue 10 2010
    L. Ř. Andersen
    Summary Wound administration of local anaesthetic may be effective for postoperative pain management in knee arthroplasty, but the analgesic efficacy of local anaesthetic in relation to volume vs concentration has not been determined. In a double-blinded trial, 48 patients scheduled for total knee arthroplasty were randomly assigned to receive either a high volume/low concentration solution of ropivacaine (20 ml, 0.5%) or a low volume/high concentration solution of ropivacaine (10 ml, 1%), 6 and 24 h postoperatively through an intracapsular catheter. Pain was assessed for 2 h after administration. Pain was reduced in both groups with ropivacaine administration 24 h postoperatively (p < 0.02), but with no difference in analgesia between groups at all time intervals. No reduction in pain scores was observed with ropivacaine injection 6 h postoperatively. The median (IQR [range]) dose of oxycodone administered was 12.5 (10,19 [0,35]) mg in the high volume/low concentration group, and 20 mg (16,40 [0,65]) mg in the low volume/high concentration group (p = 0.005). In conclusion, intracapsular administration of local anaesthetic may have limited analgesic efficacy with no volume vs concentration relationship after total knee arthroplasty. [source]

    ORIGINAL ARTICLE: Analgesic efficacy of intracapsular and intra-articular local anaesthesia for knee arthroplasty

    ANAESTHESIA, Issue 9 2010
    L. Ř. Andersen
    Summary The optimal site for wound delivery of local anaesthetic after total knee arthroplasty is undetermined. Sixty patients having total knee arthroplasty received intra-operative infiltration analgesia with ropivacaine 0.2% and were then were randomly assigned to receive either intracapsular or intra-articular catheters with 20 ml ropivacaine 0.5% given at 6 h and again at 24 h, postoperatively. Analgesic efficacy was assessed for 3 h after each injection, using a visual analogue score, where 0 = no pain and 100 = worst pain. There was no statistically significant difference between groups. Maximum pain relief (median (IQR [range])) at rest observed in the 3 h after the 6 and 24 h postoperative injections was 17 (7,31 [0,80]) and 10 (4,27 [0,50]) p = 0.27 for 6,9 h; and 17 (7,33 [0,100]) and 13 (3,25 [0,72]) p = 0.28 for 24,27 h, for intracapsular and intra-articular, respectively. Intracapsular local anaesthetic has similar analgesic efficacy to intra-articular after total knee arthroplasty. [source]

    Great auricular nerve blockade using high resolution ultrasound: a volunteer study

    ANAESTHESIA, Issue 8 2010
    A. Thallaj
    Summary This prospective, observational volunteer study aimed to describe the appearance of the great auricular nerve using ultrasound and its blockade under ultrasound guidance. An in-plane needle guidance technique was used for blockade of the great auricular nerve with 0.1 ml mepivacaine 1%. Sensory block was evaluated by pinprick testing in comparison with the contralateral area propriae. The great auricular nerve was successfully seen in all volunteers and the tail of the helix, antitragus, lobula and mandibular angle were blocked in all cases whereas the antihelix and concha were never blocked. Ultrasound imaging of the great auricular nerve can be reliably achieved and successful blockade with minimal volumes of local anaesthetic is another example of the benefits of ultrasound-guided peripheral nerve blocks. [source]

    Single-crystal diffuse scattering studies on polymorphs of molecular crystals.


    The drug benzocaine (ethyl 4-aminobenzoate), commonly used as a local anaesthetic, is a bimorphic solid at room temperature. Form (I) is monoclinic P21/c, while the metastable form (II) is orthorhombic P212121. Three-dimensional diffuse X-ray scattering data have been collected for the two forms on the 11-ID-B beamline at the Advanced Photon Source (APS). Both forms show strong and highly structured diffuse scattering. The data have been interpreted and analysed using Monte Carlo (MC) modelling on the basis that the scattering is purely thermal in origin and indicates the presence of highly correlated molecular motions. In both forms (I) and (II) broad diffuse streaks are observed in the 0kl section which indicate strong longitudinal displacement correlations between molecules in the ,031, directions, extending over distances of up to 50,Ĺ. Streaks extending between Bragg peaks in the hk0 section normal to [100] correspond to correlated motions of chains of molecules extending along a that are linked by N,H...O=C hydrogen bonds and which occur together as coplanar ribbon pairs. The main difference between the two forms is in the dynamical behaviour of the ribbon pairs and in particular how they are able to slide relative to each other. While for form (I) a model involving harmonic springs is able to describe the motion satisfactorily, as simple excursions away from the average structure, there is evidence in form (II) of anharmonic effects that are precursors of a phase transition to a new low-temperature phase, form (III), that was subsequently found. [source]

    Ultrasonographic guided axillary plexus blocks with low volumes of local anaesthetics: a crossover volunteer study

    ANAESTHESIA, Issue 3 2010
    P. Marhofer
    Summary Our study group recently evaluated an ED95 local anaesthetic volume of 0.11 ml.mm,2 cross-sectional nerve area for the ulnar nerve. This prospective, randomised, double-blind crossover study investigated whether this volume is sufficient for brachial plexus blocks at the axillary level. Ten volunteers received an ultrasonographic guided axillary brachial plexus block either with 0.11 (,low' volume) or 0.4 (,high' volume) ml.mm,2 cross-sectional nerve area with mepivacaine 1%. The mean (SD) volume was in the low volume group 4.0 (1.0) and 14.8 (3.8) ml in the high volume group. The success rate for the individual nerve blocks was 27 out of 30 in the low volume group (90%) and 30 out of 30 in the high volume group (100%), resulting in 8 out of 10 (80%) vs 10 out of 10 (100%) complete blocks in the low vs the high volume groups, respectively (NS). The mean (SD) sensory onset time was 25.0 (14.8) min in the low volume group and 15.8 (6.8) min in the high volume group (p < 0.01). The mean (SD) duration of sensory block was 125 (38) min in the low volume group and 152 (70) min in the high volume group (NS). This study confirms our previous published ED95 volume for mepivacaine 1% to block peripheral nerves. The volume of local anaesthetic has some influence on the sensory onset time. [source]

    The effect of a new topical local anaesthetic delivery system on forearm skin blood flow reactivity,

    ANAESTHESIA, Issue 2 2010
    M. D. Wiles
    Summary Different topical local anaesthetics have varying effects on skin blood flow and vascular reactivity. We compared the vasoactive properties of Rapydan®, a new topical local anaesthetic, with those of AmetopÔ and EMLAÔ creams in 20 healthy volunteers. Blood flow and vascular reactivity in the forearm skin were assessed by laser Doppler flowmetry and the transient hyperaemic response ratio respectively, before and after the application of EMLA (for 60 min), Ametop (for 30 and 60 min) and Rapydan (for 30 min). Application of EMLA had no effect on skin blood flow (median (IQR [range]) change from baseline ,0.9% (,63 to 414 [,38.5 to 51.3] %, p = 1.0)) or mean (SD) transient hyperaemic response ratio (from 2.86 (0.86) to 3.17 (1.3), p = 0.38). The application of Ametop for 60 min produced a greater median (IQR [range]) increase in blood flow from baseline (508 (,55 to 998 [148,649]) %) than Rapydan applied for 30 min 160 (,77 to 997 [45,301]) %, p = 0.001), and a similar decrease in mean (SD) transient hyperaemic response ratio (from 2.69 (1.16) to 1.08 (0.26) and from 2.83 (0.84) to 1.49 (0.93) respectively, p = 0.57). [source]

    Atomised lidocaine for airway topical anaesthesia in the morbidly obese: 1% compared with 2%,

    ANAESTHESIA, Issue 1 2010
    C. Woodruff
    Summary Airway anaesthesia using atomised lidocaine for awake oral fibreoptic intubation in morbidly obese patients was evaluated using two doses of local anaesthetic. In this randomised, blinded prospective study, 40 ml of atomised 1% (n = 11) or 2% (n = 10) lidocaine was administered with high oxygen flow as carrier. Outcomes included time for intubation, patient tolerance to airway manipulation, haemodynamic parameters, the bronchoscopist's overall satisfaction, and serial serum lidocaine concentrations. Patients receiving lidocaine 1% had a longer mean (SD) time from the start of topicalisation to tracheal tube cuff inflation than those receiving lidocaine 2% (8.6 (0.9) min vs 6.9 (0.5) min, respectively; p < 0.05). Patients in the 1% cohort demonstrated increased responses to airway manipulation (p < 0.0001), reflecting lower bronchoscopist's satisfaction scores (p < 0.03). Haemodynamic responses to topicalisation and airway manipulation were similar in both groups. Peak plasma concentration was lower in the 1% group (mean (SD) 1.4 (0.3) and 3.8 (0.5) ,g.ml,1, respectively; p < 0.001). Airway anaesthesia using atomised lidocaine for awake oral fibreoptic intubation in the morbidly obese is efficacious, rapid and safe. Compared with lidocaine 1%, the 2% dose provides superior intubating conditions. [source]

    Donor autologous blood re-infusion in total knee replacement: caution with local anaesthetic

    ANAESTHESIA, Issue 7 2009
    H. Turnham
    No abstract is available for this article. [source]

    The effect of grade of anaesthetist on outcome after day surgery,

    ANAESTHESIA, Issue 2 2009
    J. Hanousek
    Summary We conducted a retrospective survey to investigate if the grade of anaesthetist was a significant factor in determining outcome after day surgery in a district general hospital. All day surgery procedures performed between 1996 and 2006 were included except those under surgically administered local anaesthetic. The outcome measures assessed were unplanned admissions and symptoms reported after discharge. The overall admission rate was 2.6%, the admission rate for anaesthetic-related reasons was 1.5%, and 49% of patients reported some symptoms after discharge. Over the period studied the admission rate fell from 4.2% to 2.0%, admissions for anaesthetic-related reasons fell from 3.0% to 0.7% and reported symptoms fell from 67% to 37%. Consultants anaesthetists were associated with the lowest unplanned admission rate (consultants 2.3%, staff grade and associate specialists 3.1%, and trainees 3.3%), the lowest admission rate for anaesthetic reasons (consultants 1.2%, staff and associate specialists 2.0%, and trainees 1.8%), lower than expected specialty-weighted admissions and the lowest number of reported symptoms (consultants 47.3%, staff grade and associate specialists 52.6%, trainees 49.0%) (p < 0.001). We conclude that there was an improvement in outcome over the period of study and that the grade of anaesthetist is associated with outcome after day surgery. [source]

    The optimum concentration of levobupivacaine for intra-operative caudal analgesia in children undergoing inguinal hernia repair at equal volumes of injectate

    ANAESTHESIA, Issue 1 2009
    Y.-S. Yao
    Summary Probit analysis was used to predict the median effective concentration (EC50) and the 95% effective concentration (EC95) values of levobupivacaine for caudal analgesia in children at equal volumes of injectate. Sixty children scheduled for inguinal herniorrhaphy were recruited. Anaesthesia was induced with sevofurane and nitrous oxide. Then caudal block (total volume of local anaesthetic 1 ml.kg,1) was performed. Patients randomly received one of six concentrations (0.08%, 0.10%, 0.12%, 0.14%, 0.16% or 0.18%) of levobupivacaine. Thereafter, inhalational anaesthetics were discontinued and intravenous midazolam 0.1 mg.kg,1 was administered to maintain sedation. The effective caudal analgesia was defined as an absence of gross movements and a haemodynamic (heart rate or blood pressure) reaction < 20% compared with baseline in response to surgical incision. Our data indicated that the EC50 and EC95 values of levobupivacaine for caudal analgesia were 0.109% (95% confidence intervals 0.098,0.120%) and 0.151% (95% confidence intervals 0.135,0.193%) when using the same volume (1 ml.kg,1), respectively. [source]

    Trabeculectomy postponed due to volume of sub-Tenon local anaesthetic

    ANAESTHESIA, Issue 1 2009
    O. T. Sykes
    No abstract is available for this article. [source]

    The effect of warming local anaesthetic on the pain of injection during sub-Tenon's anaesthesia for cataract surgery

    ANAESTHESIA, Issue 3 2008
    M. J. Allen
    Summary In a double blind, randomised controlled trial, we examined the effect of warming local anaesthetic solutions on the pain experienced by patients undergoing a sub-Tenon's block for cataract surgery. In all, 140 patients were randomly allocated to receive either local anaesthetic stored at room temperature (control group) or local anaesthetic warmed to 37 °C (study group). Pain scores were assessed using a verbal analogue scale from 0 to 10. There was no significant difference in pain scores between the two groups. We conclude that the practice of warming local anaesthetic prior to performing a sub-Tenon's block does not significantly reduce the amount of pain experienced by patients. [source]