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Anaesthetic
Kinds of Anaesthetic Terms modified by Anaesthetic Selected AbstractsAnaesthetic ,in-flight' checks: the ABC sweepANAESTHESIA, Issue 1 2007E. G. N. Williams No abstract is available for this article. [source] 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 2004Angelo Ranise Abstract For Abstract see ChemInform Abstract in Full Text. [source] The Neurogenic Vasodilator Response to Endothelin-1: A Study in Human Skin In VivoEXPERIMENTAL PHYSIOLOGY, Issue 6 2000Ruwani 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] Pharmacological and clinical evidences on the potential for abuse and dependence of propofol: a review of the literatureFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 5 2007Anne Roussin Abstract Propofol (2,6-diisopropylphenol) is an intravenous short-acting anaesthetic widely used for inducing and maintaining anaesthesia. Propofol is also being increasingly used for sedation. Beside medical use, propofol is abused for recreational purpose, mostly in medical professionals who are not informed of the risk of dependence to this compound. The aim of this review was to provide an overview of molecular, animal and clinical pharmacological data of the literature evidencing the potential for abuse and dependence of propofol. [source] Electrical activation of common bile duct nerves modulates sphincter of Oddi motility in the Australian possumHPB, Issue 4 2005Y. 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] A review of gastrointestinal foreign bodiesINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 6 2006A. A. Ayantunde Summary Gastrointestinal tract (GIT) foreign bodies represent a significant clinical problem in the Emergency Department, causing a high degree of financial burden, morbidity and mortality. A large variety of foreign bodies are accidentally ingested or inserted into the GIT in different age groups. This a retrospective review of 38 patients who presented to the Emergency Department with GIT foreign bodies between January 2001 and December 2004. Computer database and case note search of patients' personal data, nature of the foreign objects and mode of entry to the GIT were recorded. There were 30 males and eight females (M : F ratio of 3.75:1) with an age range of 10 months to 87 years (median age 25.5 years). Foreign body ingestion/insertion was accidental in 14 patients, deliberate in 11, for anal erotism in 11 and as a result of assault in two cases. The median time before presentation was 12 h, and the mean length of hospital stay was 1.7 days. Treatment was conservative in 15 patients; five patients had gastroscopic retrieval; 15 patients underwent examination under anaesthetic, retrieval and proctosigmoidoscopy and three patients underwent laparotomy for impacted foreign bodies. GIT foreign body ingestion or insertion is common; however, majority of cases can be successfully managed conservatively. [source] Testing whether the epidural works: too time consuming?ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 6 2010J. LARSSON 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] Indigenous children and receipt of hospital dental care in AustraliaINTERNATIONAL JOURNAL OF PAEDIATRIC DENTISTRY, Issue 5 2006L. M. JAMIESON Summary., Objective., The aim of this study was to investigate dental procedures received under hospital general anaesthetic by indigenous and non-indigenous Australian children in 2002,2003. Methods., Separation data from 1297 public and private hospitals were obtained from the Australian Institute of Health and Welfare National Hospital Morbidity Database for 2002,2003. The dependant variable was the admission rate of children receiving four categories of dental care (i.e. extraction, pulpal, restoration or other). The explanatory variables included sex, age group, indigenous status and location (i.e. major city, regional or remote). Rates were calculated using estimated resident population counts. Results., The sample included 24 874 children aged from 2 to 14 years. Some 4·3% were indigenous (n = 1062). Admission rates for indigenous and non-indigenous children were similar, with indigenous males having 1·2 times the admission rate of indigenous females (P < 0·05). Indigenous children aged < 5 years had 1·4 times the admission rate of similarly aged non-indigenous children (P < 0·001) and 5·0 times the admission rate of 10,14-year-old indigenous children (P < 0·001). Remote-living indigenous children had 1·5 times the admission rate of their counterparts in major cities or regional areas (P < 0·001), and 1·4 times the admission rate of remote-living non-indigenous children (P < 0·01). The extraction rate of indigenous males was 1·3 times that of non-indigenous males (P < 0·01), and 1·2 times that of indigenous females (P < 0·05). Pre-school indigenous children had 2·2 times the extraction rate of similarly aged non-indigenous children (P < 0·001), and 5·3 times that of indigenous 10,14-year-olds (P < 0·001). The extraction rate of remotely located indigenous children was 1·5 times that of indigenous children in major cities (P < 0·01), and 1·8 times that of remote-living non-indigenous children (P < 0·001). Conclusions., In certain strata , particularly males, the very young and those in remote locations , indigenous children experienced higher rates of extractions than non-indigenous children when undergoing care in a hospital dental general anaesthetic setting. [source] Morbidity following dental treatment of children under intubation general anaesthesia in a day-stay unitINTERNATIONAL JOURNAL OF PAEDIATRIC DENTISTRY, Issue 1 2004S. Atan Summary. Objectives., To determine which variables were best related to the overall morbidity of a child undergoing dental general anaesthetic (GA) and then to use these variables to determine those factors that might influence the extent and severity of morbidity experienced by healthy children following dental GA. Sample and methods., Data were collected on anxiety, pain and morbidity, GA procedure and dental procedure from 121 children attending a day stay GA unit for dental treatment. Patients were interviewed preoperatively, postoperatively before discharge then four further times over the next 148 h. Data were analysed using multivariate regression. Results., Thirty-one per cent of subjects had restorative work, 60% had at least one tooth extracted, 54% had a surgical procedure. Use of local analgesia reduced postoperative pain whilst an increase in the number of surgical procedures increased it. Increase in anaesthetic time was related to increased odds of feeling sleepy and nauseous, females were more likely to complain of sleepiness or weakness. Feelings of dizziness were increased if the patient was given local analgesia during the procedure. Conclusions., Pain following dental GA was the most prevalent and long lasting symptom of postoperative morbidity in this study. Reductions in operating time and improvement in pain control have the potential to reduce reported morbidity following dental GA. [source] Titrated propofol induction vs. continuous infusion in children undergoing magnetic resonance imagingACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 4 2010J. E. CHO Background: Propofol is the popular intravenous (i.v.) anaesthetic for paediatric sedation because of its rapid onset and recovery. We compared the efficacy and safety of a single dose and conventional infusion of propofol for sedation in children who underwent magnetic resonance imaging (MRI). Methods: This was a double-blind, randomized-controlled study. One hundred and sixty children were assigned to group I (single dose) or II (infusion). Sedation was induced with i.v. propofol 2 mg/kg, and supplemental doses of propofol 0.5 mg/kg were administered until adequate sedation was achieved. After the induction of sedation, we treated patients with a continuous infusion of normal saline at a rate of 0.3 ml/kg/h in group I and the same volume of propofol in group II. In case of inadequate sedation, additional propofol 0.5 mg/kg was administered and the infusion rate was increased by 0.05 ml/kg/h. Induction time, sedation time, recovery time, additional sedation and adverse events were recorded. Results: Recovery time was significantly shorter in group I compared with group II [0 (0,3) vs. 1 (0,3), respectively, P<0.001]. Group I (single dose) had significantly more patients with recovery time 0 compared with group II (infusion) (65/80 vs. 36/80, respectively, P<0.001). Induction and sedation times were not significantly different between groups. There was no significant difference in the frequency of additional sedation and adverse events between groups. Conclusion: A single dose of propofol without a continuous infusion can provide appropriate sedation in children undergoing MRI for <30 min. [source] Intrathecal sufentanil decreases the median effective dose (ED50) of intrathecal hyperbaric ropivacaine for caesarean deliveryACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 3 2010X. CHEN Background: The addition of opioid to local anaesthetics has become a well-accepted practice of spinal anaesthesia for caesarean delivery. Successful caesarean delivery anaesthesia has been reported with the use of a low dose of intrathecal hyperbaric ropivacaine coadministered with sufentanil. This prospective, double-blinded study determined the median effective dose (ED50) of intrathecal hyperbaric ropivacaine with and without sufentanil for caesarean delivery, to quantify the sparing effect of sufentanil on the ED50 of intrathecal hyperbaric ropivacaine. Methods: Sixty-four parturients undergoing elective caesarean delivery with combined spinal,epidural anaesthesia were randomized into two groups: Group R (ropivacaine) and Group RS (ropivacaine plus sufentanil 5 ,g). The initial dose of ropivacaine was 13 mg in Group R and 10 mg in Group RS. The effective dose was defined as a T6 level attained within 10 min and no supplemental epidural anaesthetic required during surgery. Effective or ineffective responses determined, respectively, a 0.3 mg decrease or increase of the dose of ropivacaine for the next patient using an up,down sequential allocation. Results: The ED50 of intrathecal ropivacaine was 11.2 mg [confidence interval (CI) 95%: 11.0,11.6] in Group R vs. 8.1 mg (CI 95%: 7.8,8.3) in Group RS. Motor block was markedly more intense in Group R than in Group RS, and the incidence of shivering was lower in Group RS than in Group R. There were no differences in the onset time of sensory block or motor block, in the incidence of hypotension, nausea and vomiting. Conclusion: Intrathecal sufentanil 5 ,g produced a 28% reduction of ED50 of intrathecal hyperbaric ropivacaine for caesarean delivery. [source] Effect of short term exposure to the anaesthetic 2-phenoxyethanol on plasma osmolality of juvenile dusky kob, Argyrosomus japonicus (Sciaenidae)JOURNAL OF APPLIED ICHTHYOLOGY, Issue 3 2008A. K. Bernatzeder Summary The plasma osmolality of early juvenile dusky kob, Argyrosomus japonicus, exposed to 2-phenoxyethanol and control fish that were pithed prior to sampling, was investigated. Exposure to 2-phenoxyethanol, after 2, 4, 6, 8 and 10 min, did not alter plasma osmolality (Friedman test; P = 0.976). There was no significant relationship between the size of fish within the range 133,170 mm SL (40,85 g) and plasma osmolality. Finally, there was no significant difference in plasma osmolality between anaesthetized fish and the control group that were pithed directly after removal from the tanks. Anaesthetizing juvenile dusky kob with 2-phenoxyethanol prior to blood sampling did not affect plasma osmolality. [source] Long-lasting infiltration anaesthesia by lidocaine-loaded biodegradable nanoparticles in hydrogel in ratsACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 9 2009Q.-Q. YIN Background: Infiltration of a long-lasting anaesthetic is helpful during the post-operative period. The recently developed local drug delivery system, biodegradable nanoparticles in a thermo-sensitive hydrogel (nanogel system), may possibly provide an extended duration of drugs. Therefore, we evaluated whether prolonged infiltration anaesthesia could be achieved by loading lidocaine into this delivery system. Methods: Thirty male rats were randomized into five groups of six rats each: saline; 2% hydrochloride lidocaine solution; lidocaine-loaded nanogel system and its compositing formulations, namely lido,nano gel; lido,nano; and lidogel. Durations of local anaesthesia with subcutaneously injected agents were measured by tail flick latency tests in a randomized, blind fashion. Results: Lido,nano gel produced effective anaesthesia for 360±113 min, compared with 150±33 min by lidogel, 180±37 min by lido,nano, and 110±45 min by lidocaine solution (P<0.001, means±SD), and elicited complete sensory blockade for 300±114 min, compared with 75±37 min by lidogel, 105±53 min by lido,nano, and 60±33 min by lidocaine solution (P<0.001, means±SD) without severe skin/systemic toxicity. Conclusion: Lidocaine-loaded biodegradable nanoparticles in hydrogel produced prolonged infiltration anaesthesia in rats without severe toxicity, indicating a possible way to develop long-lasting local anaesthetics. [source] Oral myofibromatosis: an unusual cause of gingival overgrowthJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 11 2002Case 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 opioidsACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 6 2009T. 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 successful use of peripheral nerve blocks for femoral amputationACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 2 2009B. BECH We present a case report of four patients with severe cardiac insufficiency where peripheral nerve blocks guided by either nerve stimulation or ultrasonography were the sole anaesthetic for above-knee amputation. The patients were breathing spontaneously and remained haemodynamically stable during surgery. Thus, use of peripheral nerve blocks for femoral amputation in high-risk patients seems to be the technique of choice that can lower perioperative risk. [source] The role of cutaneous sensation in the motor function of the handJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 4 2004Ayman 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] Management of post-operative bladder spasmJOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 1-2 2005D Chiang Objective: Pain management following bladder surgery in children is often complicated by bladder spasm. The overall severity of spasm can be reduced with opioids, anticholinergic medication and sedatives, although breakthrough spasms often occur. At the Royal Children's Hospital, Melbourne, intravesical bupivacaine has been used to manage postoperative bladder spasm to good effect. The administration of intravesical bupivacaine is analysed in this prospective audit of locally applied intravesical anaesthetic and compared with other methods. Method: From February to August 2003, histories of 58 patients who had intravesical bupivacaine were studied and compared with six other methods of management of postoperative bladder spasm. Conclusion: Data showed that epidural anaesthesia was the most effective treatment of pain, with a pain score reduction of 6.6, compared with a reduction of 6.1 with intravesical bupivacaine, and 4.5 using intravenous morphine. However, intravesical bupivacaine was the most effective method for the relief of bladder spasm. [source] Iatrogenic injury in childhood staphylococcal scalded skin syndromeJOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 1 2003SA 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-vivoJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 6 2002Lars 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] Spinal 2-chloroprocaine: effective dose for ambulatory surgeryACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 5 2008A. SELL Background: There is an interest in finding a safe, short-acting spinal anaesthetic, suitable for ambulatory surgery. In this prospective study, we evaluated the effective dose of plain 2-chloroprocaine (2-CP) for lower limb surgery, including knee arthroscopy and saphenectomy. Methods: Sixty-four ASA physical status I,III patients undergoing elective lower limb surgery were randomly allocated to one of the four local anaesthetic groups for spinal anaesthesia in a double-blind manner. The patients (n=16 patients in each group) received 35, 40, 45 or 50 mg of 10 mg/ml isobaric 2-CP. Results: In all patients, anaesthesia was sufficient for the planned surgery. The median peak block height (T9) was similar in all four groups (P=0.66). Time to complete sensory block regression was faster in the 35 mg group (111 min, mean) and in the 40 mg group (108 min) than in the 50 mg group (134 min, P=0.005). No differences in time to complete motor block regression were observed (P=0.3). Home discharge time was faster in the 35 mg group (123 min) and in the 40 mg group (122 min) than in the 50 mg group (165 min, P=0.001). No complications related to spinal anaesthesia were observed and no transient neurologic symptoms (TNS) were reported at the 3-day follow-up. Conclusion: Spinal 2-CP, 10 mg/ml 35, 40, 45 and 50 mg provide reliable sensory and motor block for ambulatory surgery, while reducing the dose of 2-CP to 35 and 40 mg resulted in a spinal block of faster ambulation. [source] Patterns in current anaesthesiological peri-operative practice for colonic resections: a survey in five northern-European countriesACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 9 2006P. Hannemann Background:, For colorectal surgery, evidence suggests that optimal management includes: no pre-operative fasting, a thoracic epidural analgesia continued for 2 days post-operatively, and avoidance of fluid overload. In addition, no long-acting benzodiazepines on the day of surgery and use of short-acting anaesthetic medication may be beneficial. We examined whether these strategies have been adopted in five northern-European countries. Methods:, In 2003, a questionnaire concerning peri-operative anaesthetic routines in elective, open colonic cancer resection was sent to the chief anaesthesiologist in 258 digestive surgical centres in Scotland, the Netherlands, Denmark, Sweden and Norway. Results:, The response rate was 74% (n = 191). Although periods of pre-operative fasting up to 48 h were reported, most (> 85%) responders in all countries declared to adhere to guidelines for pre-operative fasting and oral clear liquids were permitted until 2,3 h before anaesthesia. Solid food was permitted up to 6,8 h prior to anaesthesia. In all countries more than 85% of the responders indicated that epidural anaesthesia was routinely used. Except for Denmark, long-acting benzodiazepines were still widely used. Short-acting anaesthetics were used in all countries except Scotland where isoflurane is the anaesthetic of choice. With the exception of Denmark, intravenous fluids were used unrestrictedly. Conclusion:, In northern Europe, most anaesthesiologists adhere to evidence-based optimal management strategies on pre-operative fasting, thoracic epidurals and short-acting anaesthetics. However, premedication with longer-acting agents is still common. Avoidance of fluid overload has not yet found its way into daily practice. This may leave patients undergoing elective colonic surgery at risk of oversedation and excessive fluid administration with potential adverse effects on surgical outcome. [source] Single-dose dexmedetomidine attenuates airway and circulatory reflexes during extubationACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 8 2005G. Guler Background:, The alpha agonist dexmedetomidine, a sedative and analgesic, reduces heart rate and blood pressure dose-dependently. We investigated whether it also has the ability to attenuate airway and circulatory reflexes during emergence from anaesthesia. Methods:, Sixty ASA I,III patients received a standard anaesthetic. Five minutes before the end of surgery, they were randomly allocated to receive either dexmedetomidine 0.5 µg/kg (Group D) (n = 30) or saline placebo (Group P) (n = 30) intravenously (i.v.) over 60 s in a double-blind design. The blinded anaesthetist awoke all the patients, and the number of coughs per patient was continuously monitored for 15 min after extubation; coughing was evaluated on a 4-point scale. Any laryngospasm, bronchospasm or desaturation was recorded. Heart rate (HR) and systolic and diastolic blood pressure (SAP, DAP) were measured before, during and after tracheal extubation. The time from tracheal extubation and emergence from anaesthesia were recorded. Results:, Median coughing scores were 1 (1,3) in Group D and 2 (1,4) in Group P (P < 0.05), but there were no differences between the groups in the incidence of breath holding or desaturation. HR, SAP and DAP increased at extubation in both groups (P < 0.05), but the increase was less significant with dexmedetomidine. The time from tracheal extubation and emergence from anaesthesia were similar in both groups. Conclusion:, These findings suggest that a single-dose bolus injection of dexmedetomidine before tracheal extubation attenuates airway-circulatory reflexes during extubation. [source] Effects of isoflurane on measurements of delayed lumininescence in Acetabularia acetabulumLUMINESCENCE: THE JOURNAL OF BIOLOGICAL AND CHEMICAL LUMINESCENCE, Issue 1 2005Wen Li Chen Abstract The volatile halogenated methyl ethyl ether, isoflurane, used as an anaesthetic, inhibits actin-based dynamics directly or indirectly in animal cells. In plant cells, most intracellular movements are related to actin pathways. We have used isoflurane in a unicellular alga, Acetabularia acetabulum, to test the dynamics of choloroplast organization. By measuring the delayed luminescence, we found that isoflurane worked efficiently in the unicellular organism and showed dose- and time-course-dependent actin-inhibition patterns. When A. acetabulum was treated with saturated solutions of isoflurane in artificial seawater (defined as 100% isoflurane) for 3 or 6 min, the delayed luminescence (DL) was decreased and was never recovered. In contrast, if treated with 75% diluted isoflurane, the DL was firstly inhibited and then recovered several hours later, and if treated with 50% diluted isoflurane, the change of DL was small. Our work proved that isoflurane can affect actin-related pathways in both animals and plants. Copyright © 2005 John Wiley & Sons, Ltd. [source] Sevoflurane: an ideal agent for adult day-case anesthesia?ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 8 2003S. Ghatge Sevoflurane has several properties which make it potentially useful as a day case anaesthetic. Following induction of anaesthesia with propofol, awakening from sevoflurane is faster compared to isoflurane, faster or similar compared to propofol and comparable (in the majority of studies) to desflurane. Subsequent recovery and discharge is generally similar following all agents. Sevoflurane may also be used to induce anaesthesia, which is generally well-received and causes less hypotension and apnoea compared to propofol. When used as a maintenance anaesthetic, the incidence of postoperative nausea and vomiting after sevoflurane is comparable to other inhaled anaesthetics, but this complication appears more common after inhaled inductions. The tolerability and low solubility of sevoflurane facilitate titration of anaesthesia and may reduce the need for opioid analgesia, which in turn may limit the occurrence of nausea and vomiting. [source] The effect of sevoflurane on glutamate release and uptake in rat cerebrocortical presynaptic terminalsACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 1 2002M. L. Vinje Background: Volatile anaesthetics exert their effect in the brain mainly by reducing synaptic excitability. Isoflurane abates excitation by reducing the release and increasing the uptake of transmitter glutamate into the presynaptic terminal. The exact molecular mechanisms exerting these effects, however, are not clear. Voltage-gated calcium channels have been proposed as the pharmacological target. The present study examines the effect of sevoflurane on synaptic glutamate release and free cytosolic calcium and the effect on high- and low-affinity uptake of L-glutamate using isolated presynaptic terminals prepared from rat cerebral cortex. Methods: Released glutamate was measured fluorometrically in a spectrophotometer as the fluorescence of NADPH and calcium as the fluorescence of fura-2. 4-aminopyridine was used to induce membrane depolarization. Glutamate uptake was measured in a series of different concentrations of L-glutamate corresponding to the high- and the low- affinity uptake systems adding a fixed concentration og radiolabelled glutamate. The labelling was measured by counting disintegrations per min in a ,-scintillation counter. Results: Sevoflurane reduced the calcium-dependent glutamate release in a dose-dependent manner as sevoflurane 1.5, 2.5 and 4.0% reduced the release by 58, 69 and 94%, respectively (P<0.05). Membrane depolarization induced an increase in free cytosolic calcium by 25%. Sevoflurane did not affect this increase. Neither the high- nor the low-affinity uptake transporter systems are affected by the anaesthetic. Conclusion: These results indicate that different volatile anaesthetics may act differently on the presynaptic terminal. The exact modes of action have to be further investigated. [source] Complaints related to respiratory events in anaesthesia and intensive care medicine from 1994 to 1998 in DenmarkACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 1 2001C. Rosenstock Background: In Denmark, a National Board of Patients' Complaints (NBPC) was founded in 1988. This study analyses anaesthetic complaints related to adverse respiratory events filed at the NBPC from 1994 to 1998 to point out directions for possible preventive measures. Methods: All decisions made by the NBPC from 1994 to 1998 concerning personnel employed in the Danish health care system were scrutinized. Cases related to anaesthesia and intensive care medicine were reviewed. Adverse respiratory events were identified and classified by mechanism of the incident that had caused the complaint. Detailed information on anaesthetic technique, personnel involved, sequence of events, clinical manifestation of injury, and outcome was recorded. Results: A total of 284 cases was identified. One-fifth (n=60) of the complaints were related to an adverse respiratory event. The overall mortality in these cases was 50% (n=30). In 19 complaints (32%), the treatment was considered substandard. Conclusion: Complaints related to respiratory events reveal that inadequate anaesthetic and intensive care medicine treatment leads to patient damage and death. Preventive strategies should be directed at the development of guidelines for handling the difficult airway, education in the management of the difficult airway, instruction in the correct use of anaesthetic equipment, improvement of interpersonnel communication routines, as well as implementation of simulator training. [source] Anaesthetic choice for palatal canine exposureORAL SURGERY, Issue 1-2 2010S. 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] Does halothane or isoflurane affect hypoxic and post-hypoxic vascular response in rabbit aorta?ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 4 2000E. Haddad Background: Halothane and isoflurane affect differently endothelium-dependent and -independent vasorelaxation at 95% O2. In addition, hypoxic vascular response might involve endothelium-dependent and -independent mechanisms. Therefore, we investigated, in rabbit aortic rings, 1) the influence of halothane and isoflurane on vasodilation at 95% O2 and on hypoxic-induced vasorelaxation at 0% O2 and 2) the influence of halothane and isoflurane on endothelium-dependent and -independent post-hypoxic vascular response. Methods: Endothelium-intact and endothelium-denuded rabbit aortic rings were used. Phenylephrine precontracted rings were exposed, at 95% O2, to acetylcholine (ACh, 10,9 to 10,4 M) or sodium nitroprusside (SNP, 10,9 to 10,4 M) in the presence or absence of anaesthetic at 1 or 2 MAC. Precontracted rings were also exposed to an acute reduction in O2 from 95% to 0% followed by an acute reoxygenation with 95% O2 in the absence or presence of anaesthetic at 1 or 2 MAC. Results: At 95% O2, halothane decreased endothelium-dependent relaxation to ACh, while endothelium-independent relaxation to SNP was decreased only at 2 MAC. Isoflurane did not modify ACh- or SNP-induced relaxation. At 0% O2, neither halothane nor isoflurane altered the hypoxic vascular relaxation. Post-hypoxic response was not changed either. Conclusion: Our results indicate that halothane and isoflurane do not alter vascular hypoxic response in conductance arteries. [source] A comparison of coracoid and axillary approaches to the brachial plexusACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 3 2000Z. 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] | |||||||||||||||||||||||||||||||||||||||||||