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Background and Aim: Intrathecal fentanyl, using the combined spinal-epidural (CSE) technique, provides rapid analgesia during early labour. Because of the technique's more complex and invasive nature, as its replacement we assessed the use of epidural analgesia in primiparous parturients with induced labour. The study was registered at www., Clinicaltrials: gov (NCT04645823). The aim was to compare the efficacy, duration of analgesia and maternal satisfaction. The primary outcome was the difference in pain visual analogue scale (VAS) between the interventions at 20 min after the analgesia administration., Methods: Sixty volunteering parturients were randomly allocated in 1:1 ratio to receive either intrathecal fentanyl 20 μg or epidural analgesia (fentanyl 100 μg and lidocaine 80 mg). Contraction pain and maternal satisfaction were assessed by 0-100 mm VAS for 30 min, respectively. Foetal heart rate abnormalities, the time to first epidural dose and the incidence of pruritus were recorded. Non-inferiority margin for mean (95% CI) VAS after epidural analgesia was set at 20 mm above the VAS value for intrathecal fentanyl at 20 min., Results: The contraction pain VAS fell from (median [interquartile range, IQR]) 82 (14) to 13 (20) mm and 76 (17) to 12 (27) mm in 20 min following the intrathecal fentanyl and epidural analgesia, respectively. The absolute mean difference (epidural-intrathecal fentanyl) in the VAS values was 3.3(-0.06 to 6.66) mm indicating non-inferiority. The median time to reach VAS <30 mm was 10 min in both groups. The duration until request for supplemental analgesia was 82(69-95) and 91(75-106) min after intrathecal fentanyl and epidural analgesia, respectively. The difference for the duration (epidural-intrathecal fentanyl) was 9 (6-12) min and for satisfaction-VAS 0.3 (-3.0 to 3.7) mm. There were no differences between the groups in the incidence of foetal heart rate abnormalities, while pruritus was more common after intrathecal fentanyl., Conclusion: After 20 min, epidural analgesia by lidocaine and fentanyl was within the non-inferior threshold compared with intrathecal fentanyl in efficacy. The duration of action was not shorter than that of intrathecal fentanyl and maternal satisfaction was also similar., (© 2024 The Authors. Acta Anaesthesiologica Scandinavica published by John Wiley & Sons Ltd on behalf of Acta Anaesthesiologica Scandinavica Foundation.)

Background: The reported variation in nerve block duration is considerable. To individualize nerve block therapy, knowledge of the intra- vs inter-individual variability is essential. We investigated the relative contribution of these 2 parameters to the overall nerve block duration variability.Methods: With ethics committee approval, we conducted a randomized cross-over trial where 20 healthy volunteers received 8 common peroneal nerve blockades with lidocaine 0.5% on 4 consecutive days. Allocations were 5 mL to either the right or left side and 10 mL to the opposite side on day 1 and 2 and vice versa on day 3 and 4. With fixed needle entry and nerve target, we repeated local anaesthetic deposition for each blockade. The primary outcome was variation in duration of sensory nerve block defined as insensitivity to a cold stimulus. Data were analysed using linear mixed model regression.Results: The mean sensory block duration of 380 (95% CI = [342; 418]) minutes on day one was 55 [33; 77] minutes longer than on day two (P < .001), but there were no differences in mean duration between days 2, 3 and 4. The ratios with 2.5; 97.5 percentiles between inter- and intra-individual variation were 2.4 [0.8; 5.2] for the 5 mL blockades and 3.0 [0.9; 6.7] for the 10 mL blockades. The probabilities of inter- to intra-individual variation-ratios >1 were 96% and 97%.Conclusion: The intra-individual variability is a substantially minor contributor to the overall variability in sensory nerve block duration compared with the inter-individual variability. [ABSTRACT FROM AUTHOR]

Background: A femoral nerve block relieves pain after total hip arthroplasty, but its use is controversial due to motor paralysis accompanied by an increased risk of fall. Assumedly, the iliopsoas plane block (IPB) targets the hip articular branches of the femoral nerve without motor blockade. However, this has only been indicated in a cadaver study. Therefore, we designed this volunteer study.Methods: Twenty healthy volunteers were randomly allocated to blinded paired active vs. sham IPB (5 mL lidocaine 18 mg/mL with epinephrine vs saline). The primary outcome was reduction of maximal force of knee extension after IPB compared to baseline. Secondary outcomes included reduction of maximal force of hip adduction, and the pattern of injectate spread assessed with magnetic resonance imaging.Results: Mean (confidence interval) change of maximal force of knee extension from baseline to after IPB was -9.7 N (-22, 3.0) (P = .12) (n = 14). The injectate was consistently observed in an anatomically well-defined closed fascial compartment between the intra- and extra-pelvic components of the iliopsoas muscle anterior to the hip joint.Conclusion: We observed no significant reduction of maximal force of knee extension after an IPB. The injectate was contained in a fascial compartment previously shown to contain all sensory branches from the femoral nerve to the hip joint. The clinical consequence of selective anesthesia of all sensory femoral nerve branches from the hip could be a reduced risk of fall compared to a traditional femoral nerve block. Registration of Trial: The trial was prospectively registered in EudraCT (Reference: 2018-000089-12, https://www.clinicaltrialsregister.eu/ctr-search/search?query=2018-000089-12). [ABSTRACT FROM AUTHOR]

Background: Local anaesthetics (LA) are often suspected as possible causes of allergic reactions. The Danish Anaesthesia Allergy Centre (DAAC) is the national reference centre for investigation of perioperative allergic reactions. The purpose of this study was to investigate the incidence of IgE-mediated immediate type perioperative allergic reactions to LA.Methods: In the period 2004-2013, a total of 409 patients (244 women/165 men; median age 49 years, range 1-86 years) were investigated in DAAC on suspicion of allergy associated with anaesthesia and surgery. A total of 162 (40%) patients were exposed to one or more LA. Suspected allergy to LA was investigated by prick test, intradermal test and subcutaneous provocation with the suspected drug. Patients with positive skin tests still underwent subcutaneous provocation, as false positive skin tests can occur.Results: A total of 203 test series with LA were carried out on 162 patients (89 women/73 men; mean age 49 years, range 2-85 years) with the following drugs: Lidocaine n = 80 (49%), bupivacaine n = 82 (51%), ropivacaine n = 31 (19%) and mepivacaine n = 10 (6%). All 162 patients had negative subcutaneous provocation for all tested LA (95% CI: 0-1.8%). Investigations revealed another allergen in 52 of 162 patients.Conclusion: None of the 162 patients with suspected perioperative allergic reactions and exposure to LA reacted on subcutaneous provocation with the relevant LA. Thus, no patients have been diagnosed with allergy to LA in DAAC in the period 2004-2013 and allergy to LA must be considered very rare in this population. [ABSTRACT FROM AUTHOR]

Background and Objectives: Transversus abdominis plane block (TAP) and intravenous lignocaine are two analgesic techniques frequently used after abdominal surgery. We hypothesized that these two techniques improve post-operative analgesia after open prostate surgery and sought to compare their efficacy on immediate post-operative outcome after open prostate surgery.Methods: After ethics committee approval, 101 patients were enrolled in this prospective study and randomly allocated to receive bilateral ultrasound-guided TAP (n = 34), intravenous lignocaine (n = 33) or placebo (n = 34). In addition, intravenous paracetamol was given every 6 h. The primary endpoint was the cumulative opioid consumption during the first 48 post-operative hours (median[IQR]). Secondary endpoints included pain scores at rest and upon coughing, need for rescue tramadol, incidence of post-operative nausea and vomiting (PONV), recovery of bowel function and incidence of bladder catheter-related discomfort.Results: Cumulative piritramide consumption after 48 h was 28 [23] mg in the control group, 21 [29] mg in the TAP group and 21 [31] mg in the lignocaine group (P = 0.065). There was no significant difference in post-operative pain scores between groups. The proportions of patients requiring rescue tramadol, experiencing PONV or bladder catheter-related discomfort were similar in each group. Recovery of bowel function was also similar in the three groups.Conclusions: Our study suggests that TAP block and intravenous lignocaine do not improve the post-operative analgesia provided by systematic administration of paracetamol after open prostatectomy. [ABSTRACT FROM AUTHOR]

Background Endothelin-1 ( ET-1) induces pain-like behavior in animals and man by activating the Gq protein-coupled receptor endothelin- A ( ETA). Activation of ETA receptors on nociceptor membranes evokes intracellular calcium transients and alters membrane Na+ and K+ channel and TRPV1 currents, leading to neuronal hyper-excitability manifested by spontaneous and evoked pain behaviors in vivo. In addition to blocking sodium channels, local anesthetics inhibit the Gq protein-coupled signaling of several inflammatory and pro-algesic mediators. In this study, we aimed to investigate the actions of local anesthetics on ETA-mediated increases in intracellular calcium in ND7/104 model sensory neurons. Methods Increases in intracellular calcium were measured by the fluorescent indicator fura-2 in a sensory neuron-derived cell line ( ND7/104), which endogenously expresses ETA receptors. Effects of lidocaine and bupivacaine, along with their respective membrane-impermeant derivatives QX-314, LEA-123 and LEA-124, on peak calcium responses to ET-1 were measured. Results Bupivacaine suppressed ET-1 responses in a concentration-dependent and non-competitive manner with an IC50 of 3.79 ± 1.63 mM. Bupivacaine (6 mM) reduced the Emax for ET-1 from 50.07 ± 1.91 mM to 27.30 ± 2.92 mM. The actions of bupivacaine occurred quickly and were rapidly reversible. Membrane-impermeant analogs of bupivacaine ( LEA-123 and LEA-124, 6 mM) were without effect, as was lidocaine (10 mM) and its quaternary derivative QX-314 (10 mM). Conclusion Bupivacaine inhibits ETA-mediated calcium transients at clinically relevant concentrations through an intracellular target. The anti-inflammatory and analgesic actions of bupivacaine may be at least partially due to its inhibitory action on Gq-coupled receptors, including ETA. [ABSTRACT FROM AUTHOR]

Background Mechanical ventilation ( MV) induces an inflammatory response that may result in (acute) lung injury. Lidocaine, an amide local anesthetic, has anti-inflammatory properties in vitro and in vivo, possibly due to an attenuation of pro-inflammatory cytokines, intracellular adhesion molecule-1 ( ICAM-1), and reduction of neutrophils influx. We hypothesized an attenuation of MV-induced inflammatory response with intravenously administered lidocaine. Methods Lidocaine ( Lido) (2, 4, and 8 mg/kg/h) was intravenously administered during 4 h of MV with a tidal volume of 8 ml/kg, positive end expiratory pressure 1,5 cmH2O and FiO2 0.4. We used one ventilated control ( CON) group receiving vehicle. After MV, mice were euthanized, and lungs and blood were immediately harvested, and cytokine levels and ICAM-1 levels were measured in plasma and lung homogenates. Pulmonary neutrophils influx was determined in LEDER-stained slices of lungs. Anesthetic need was determined by painful hind paw stimulation. Results Lidocaine-treated animals ( Lido 2, 4 and 8 mg/kg/h) showed higher interleukin ( IL)-10 plasma levels compared to control animals. Lidocaine treatment with 8 mg/kg/h ( Lido 8) resulted in higher IL-10 in lung homogenates. No differences were observed in pro-inflammatory cytokines, ICAM-1, and pulmonary influx between the different ventilated groups. Conclusions Intravenously administered lidocaine increases levels of plasma IL-10 with infusion from 2, 4, and 8 mg/kg/h and pulmonary levels of IL-10 with 8 mg/kg/h in a murine mechanical ventilation model. Intravenously administered lidocaine appears to reduce anesthetic need in mice. [ABSTRACT FROM AUTHOR]

Background Hemorrhagic shock may trigger an inflammatory response and acute lung injury. The combination adenosine, lidocaine ( AL) plus Mg2+ ( ALM) has organ-protective and anti-inflammatory properties with potential benefits in resuscitation.The aims of this study were to investigate: (1) pulmonary function and inflammation after hemorrhagic shock; (2) the effects of ALM/ AL on pulmonary function and inflammation. Methods Pigs (38 kg) were randomized to: sham + saline ( n = 5); sham + ALM/ AL ( n = 5); hemorrhage control ( n = 11); and hemorrhage + ALM/ AL ( n = 9). Hemorrhage animals bled to a mean arterial pressure ( MAP) of 35 mmHg for 90 min, received resuscitation with Ringer's acetate and 20 ml of 7.5% NaCl with ALM to a minimum MAP of 50 mmHg, after 30 min shed blood and 0.9% NaCl with AL were infused. Hemorrhage controls did not receive ALM/ AL. Primary endpoints were pulmonary wet/dry ratio, PaO2/ FiO2 ratio (partial pressure of arterial oxygen to the fraction of inspired oxygen), cytokine and protein measurements in bronchoalveolar lavage fluid ( BALF) and lung tissue, neutrophil invasion and blood flow in lung tissue. Results In the hemorrhage groups, wet/dry ratio increased significantly compared with the sham groups. PaO2/ FiO2 ratio decreased during shock but normalized after resuscitation. BALF did not indicate significant pulmonary inflammation, oxidative stress or increased permeability. Intervention with ALM caused a temporary increase in pulmonary vascular resistance and reduced urea diffusion across the alveolar epithelia, but had no effect on wet/dry ratio. Conclusion Hemorrhagic shock and resuscitation did not cause acute lung injury or pulmonary inflammation. The question whether ALM/ AL has the potential to attenuate acute lung injury is unanswered. [ABSTRACT FROM AUTHOR]

Background This randomised, double blind prospective study compares intrathecal lidocaine with chloroprocaine in day-case surgery and the influence of a 500 ml pre-load intravenously. We tested the hypothesis that chloroprocaine provides faster recovery and discharge in day-case surgery. Secondary we studied the influence of a preload compared with fluid restriction on discharge time and micturition problems. Methods One hundred patients undergoing day-case arthroscopy were randomised to receive either lidocaine ( L) 60 mg or chloroprocaine ( CP) 40 mg intrathecally and this with ( L+, CP+) or without ( L−, CP−) a 500 ml pre-load of crystalloid. Block characteristics, micturition and discharge times were registered. Bladder volumes were monitored by ultrasound. Micturition problems received a micturition score. Results Onset and quality of the block were comparable between groups. Time to regain Bromage 1 and L2 regression were shorter for the CP group compared with the L group. Voiding (168 ± 44 min) and discharge (178 ± 52 min) were approximately 40 min faster for the CP group compared with the L group. Pre-load provided faster bladder filling but there were no differences in voiding time within the CP or L group. The CP+ group (166 ± 36 min) was discharged faster than both L groups (226 ± 57 min, 227 ± 59 min). More serious micturition problems occurred in the L+ group compared with both CP groups. Conclusion Chloroprocaine is suitable for day-case surgery because of faster block regression and discharge than lidocaine. A 500 ml pre-load may not affect discharge but did not increase micturition problems for chloroprocaine. [ABSTRACT FROM AUTHOR]

Background Two spinal anaesthesia techniques were compared with local infiltration anaesthesia ( LIA) to test the hypothesis that the addition of lidocaine to bupivacaine would decrease the spinal block's duration and provide shorter recovery to discharge. Methods Ninety-three patients undergoing outpatient herniorrhaphy were randomised into three groups. Spinal anaesthesia: the BL Group (bupivacaine-lidocaine) received 2 ml hyperbaric bupivacaine (10 mg) + 0.6 ml 1% lidocaine (6 mg), the BS Group (bupivacaine-saline) received 2 ml hyperbaric bupivacaine (10 mg) + 0.6 ml saline. LIA: the LIA group received plain bupivacaine + lidocaine. Resolution of the nerve blocks were compared between spinal anaesthesia groups, and post-operative pain scores, analgesic requirements, post-anaesthesia care unit ( PACU) time, and discharge time were compared among all groups. Results Spinal block resolved faster in the BL group vs. the BS group: 194.8 [standard deviation ( SD) 29.2] min vs. 236.8 ( SD 36.5) min ( P = 0.000). PACU and discharge time were shortest in the LIA group [ PACU time: 108.7 ( SD 27.6) min vs. 113.0 ( SD 39.4) min and 151.9 ( SD 43.7) min in the BL and BS groups ( P = 0.000), and discharge time 108.5 ( SD 29.5) min vs. 145.8 ( SD 37.3) min and 177.1 ( SD 32.0) min in the BL and BS groups, respectively ( P = 0.000)]. Pain scores and analgesic consumption were lower, with the time to first analgesic intake being longer in the LIA group. Conclusion Addition of lidocaine to bupivacaine reduced the duration of the spinal block and was associated with shorter recovery times. However, LIA provided the fastest recovery to discharge after outpatient inguinal herniorrhaphy. [ABSTRACT FROM AUTHOR]

Background Articaine and chloroprocaine have recently gained interest as short-acting spinal anaesthetics. Based on previous work comparing articaine 60 mg with chloroprocaine 40 mg, we hypothesised that articaine 40 mg and chloroprocaine 40 mg would produce similar spinal anaesthesa regarding block onset, maximal spread, and recovery. Methods In this randomised, double-blind study, adult patients (18-70 years, American Society of Anaesthesiologists physical status I- III, BMI < 36 kg/m2) scheduled for day-case knee arthroscopy received either articaine 40 mg (20 mg/ml) (group A40, n = 16) or chloroprocaine 40 mg (20 mg/ml) (group C40, n = 18) intrathecally. Telephone interviews were performed on the first and seventh postoperative day to disclose possible side effects, e.g. transient neurological symptoms ( TNS). Results The groups were comparable regarding demographic data, onset and maximal spread of spinal anaesthesia, and duration of surgery. Surgery could be performed successfully under spinal anaesthesia except once in A40 (insufficient block) and once in C40 (prolonged surgery). Complete recovery was significantly slower in A40 vs. C40 for both motor block (105 (94/120) vs. 75 (71/90) min) [ P < 0.001, Mann- Whitney U-test ( MW- U)] and sensory block [135 (109/176) vs. 105 min (90/124)] ( P < 0.02, MW- U), respectively [data are median (25th/75th percentiles)]. One patient from A40 showed mild TNS. Conclusion Both A40 and C40 provided mainly adequate spinal anaesthesia for day-case knee arthroscopy. While onset and maximal spread were comparable, the recovery from motor block was clearly faster with chloroprocaine after equivalent doses of spinal articaine and chloroprocaine. [ABSTRACT FROM AUTHOR]

Spinal anaesthesia is a safe and reliable anaesthetic modality for surgical procedures on the lower part of the body. However, because of the description of transient neurologic symptoms ( TNS), most practitioners have abandoned intrathecal lidocaine. Chloroprocaine (2-chloroprocaine, CP) has been one candidate to replace lidocaine for short procedures, despite the fact that neurologic sequelae have been described following the intrathecal injection of large doses of preservative-containing CP intended for epidural use. The National Library of Medicine's Medline and the EMBASE databases were searched for the time period 1966 to April 2012. Fourteen studies of the use of intrathecal CP were analysed, including seven volunteer and seven clinical studies. Preservative-free CP appears to be a reliable local anaesthetic for short procedures. The duration of the surgical block can be adjusted by varying the dose between 30 and 60 mg. Two double-blind randomised controlled studies demonstrate decreased time to ambulation and discharge when CP is used for spinal anaesthesia when compared with other local anaesthetics. The addition of fentanyl appears to prolong the surgical block without significantly prolonging the time to discharge. There have been five possible cases of TNS following CP spinal anaesthesia in over 4000 patients, and a regressive incomplete cauda equina syndrome has been described. The short duration of spinal CP makes it a strong contender for outpatient anaesthesia. It appears to have a lower risk of TNS than lidocaine. [ABSTRACT FROM AUTHOR]

Background Post-operative sore throat ( POST) has increasingly been a common clinical complication particularly in thyroid surgery. We conducted a trial to evaluate the effect of non-pharmacological [smaller-sized endotracheal tube ( ETT)] combined with pharmacological intervention [lidocaine intravenous (i.v.)] on POST in women undergoing thyroid surgery. Methods Two hundred and forty patients scheduled for thyroid surgery were randomly divided into four groups: Group A, ETT size 7.0 with saline; Group B, ETT size 6.0 with saline; Group C, ETT size 7.0 with lidocaine; Group D, ETT size 6.0 with lidocaine. Patients in Groups C and D received i.v. 1.5 mg/kg lidocaine that was filled in syringe up to 10 ml 5 min before induction of anaesthesia; whereas patients in Groups A and B received an equal volume of saline. The incidence and severity of POST were evaluated at 1, 6 and 24 h after tracheal extubation. Results The highest incidence of POST occurred at 6 h after extubation in all groups. The incidence of POST was significantly lower in Group D compared with Groups A (23% vs. 62%, P < 0.01), B (23% vs. 42%, P = 0.03) and C (23% vs. 43%, P = 0.02) at 6 h after extubation. Group D had significantly decreased severity of POST compared with Groups A, B and C 6 and 24 h after extubation ( P < 0.05). Conclusion Use of smaller-sized ETT combined with i.v. lidocaine decreases the incidence and severity of POST in women undergoing thyroid surgery. [ABSTRACT FROM AUTHOR]

Background Non-steroidal anti-inflammatory drugs are analgesics commonly used for post-operative pain. However, their effect on dosages of inhaled anesthetics during surgery is unclear. We investigated the effect of flurbiprofen axetil and parecoxib sodium on the minimum alveolar concentration of sevoflurane required to blunt stress responses to skin incision under general anesthesia. Methods One hundred and five adult patients were randomly allocated to four treatment groups, each receiving sevoflurane: control (sevoflurane only), lidocaine (1 mg/kg bolus, followed by continuous infusion of 20 μg/kg/min after intubation), Intravenous ( IV) flurbiprofen (1 mg/kg before skin incision), and IV parecoxib (40 mg before skin incision). Following anesthetic induction and stabilization of end-tidal sevoflurane concentration, mean arterial blood pressure and heart rate were recorded 2 min before and at 5-min intervals after skin incision. The stable end-tidal sevoflurane concentration was calculated using an up-and-down method. Results The minimum alveolar concentration of sevoflurane required to blunt the stress responses to skin incision in the control, lidocaine, flurbiprofen, and parecoxib groups was 4.63 ± 0.08%, 2.67 ± 0.08%, 3.33 ± 0.08%, and 3.80 ± 0.11%, respectively. These figures for the later three groups were all significantly less than that of the control group ( P = 0.021, P = 0.037, and P = 0.011, respectively); that of the flurbiprofen group was significantly less than the parecoxib ( P = 0.034). Conclusion The non-steroidal anti-inflammatory drugs flurbiprofen axetil and parecoxib sodium decreased the minimum alveolar concentration of sevoflurane required to blunt the stress response to skin incision during general anesthesia. [ABSTRACT FROM AUTHOR]

Background Intravenous lidocaine is increasingly used in surgical patients. As it has neuromuscular blocking effects, we tested the impact of an intravenous lidocaine infusion on the time course of a rocuronium-induced neuromuscular block. Methods Fifty-two adults undergoing surgery were randomly allocated to intravenous lidocaine 1.5 mg/kg followed by a continuous infusion of 2 mg/kg/h or physiological saline (control) throughout surgery. Anaesthesia was induced and maintained with a target-controlled propofol infusion and sufentanil. After loss of consciousness, rocuronium 0.6 mg/kg was given. Neuromuscular transmission was measured using train-of-four ( TOF)-watch SX (Organon, Swords Co., Dublin, Ireland) acceleromyography. Results Onset time (to 95% depression of first twitch) was on average 113.9 s (standard deviation 35.3) with lidocaine and 119.5 s (44.9) with saline ( P = 0.618). Total recovery time ( TOF ratio 0.9) was on average 58.1 min (15.1) with lidocaine and 54.3 min (16.9) with saline ( P = 0.394). Clinical duration (until first twitch has recovered to 25%) was on average 33.3 min (7.2) with lidocaine and 30.6 min (8.1) with saline ( P = 0.21). Recovery index (time between 25% and 75% recovery of the first twitch) was on average 11.5 min (5.0) with lidocaine and 10.6 min (4.1) with saline ( P = 0.458). Recovery time (between 25% recovery of the first twitch and TOF ratio 0.9) was on average 24.8 min (9.3) with lidocaine and 23.2 min (9.2) with saline ( P = 0.541). Conclusion A continuous intravenous infusion of lidocaine has no impact on the time course of the neuromuscular blockade induced by a standard intubation dose of rocuronium. [ABSTRACT FROM AUTHOR]

Recent volunteer and clinical studies of chloroprocaine (CP) have evaluated its use for outpatient spinal anesthesia. This retrospective review describes the discharge characteristics and reported side effects of spinal CP in a large number of patients undergoing outpatient procedures. All patients who received spinal anesthesia for ambulatory procedures over a 20-month period were accessed using computer-generated reports. Charts from 601 anesthetics were analyzed for spinal drug used, block characteristics, side effects and discharge data. CP was the most frequently used spinal anesthetic (84% of cases, n=503) for outpatient procedures. CP (median dose 40 mg, range 20-60 mg) times from injection to ambulation and discharge were 107 ± 24 and 171 ± 45 min, respectively. Lidocaine (median dose 60 mg, range 30-100 mg, n=84) times from injection to ambulation and discharge were 155 ± 40 and 224 ± 57 min, respectively ( P<0.05). The incidence of urinary retention, the most common side effect, was similar in both groups. There were no reports of transient neurologic symptoms. For ambulatory patients at our institution, the time to achievement of discharge criteria was significantly reduced with CP 40 vs. lidocaine 60 mg. There have been no reports of perioperative neurologic injury with the introduction of CP as a spinal anesthetic at our institution. [ABSTRACT FROM AUTHOR]

Background: Intravenous lidocaine can be used intraoperatively for its analgesic and antihyperalgesic properties but local anaesthetics may also prolong the duration of action of neuromuscular blocking agents. We hypothesized that intravenous lidocaine would prolong the time to recovery of neuromuscular function after cisatracurium. Methods: Forty-two patients were enrolled in this randomized, double-blind, placebo-controlled study. Before induction, patients were administered either a 1.5 mg/kg bolus of intravenous lidocaine followed by a 2 mg/kg/h infusion or an equal volume of saline. Anaesthesia was induced and maintained using propofol and remifentanil infusions. After loss of consciousness, a 0.15 mg/kg bolus of cisatracurium was administered. No additional cisatracurium injection was allowed. Neuromuscular function was assessed every 20 s using kinemyography. The primary endpoint was the time to spontaneous recovery of a train-of-four (TOF) ratio ≥0.9. Results: The time to spontaneous recovery of a TOF ratio ≥0.9 was 94 ± 15 min in the control group and 98 ± 16 min in the lidocaine group ( P=0.27). Conclusions: No significant prolongation of spontaneous recovery of a TOF ratio ≥0.9 after cisatracurium was found in patients receiving intravenous lidocaine. [ABSTRACT FROM AUTHOR]

Background: Transient neurological symptoms (TNS) after spinal anaesthesia have been reported most commonly in association with lidocaine, but have been observed with other local anaesthetics. The aim of this prospective, randomized, double-blind study was to investigate the incidence of TNS after spinal anaesthesia with either levobupivacaine or lidocaine. Methods: Patients undergoing inguinal hernia, appendectomy, varicose vein or minor orthopaedic operations were included in the study (60 patients; 47 male, 13 female, overall mean age 30 years). All patients had an American Society of Anesthesiologists score of I or II. The patients were randomly assigned to receive spinal anaesthesia with either 20 mg isobaric levobupivacaine (5 mg/ml) or 80 mg isobaric lidocaine (20 mg/ml). Onset of sensory and motor block and side effects were recorded. On post-operative days 1, 2, and 3, patients were interviewed by an investigator blinded to the spinal anaesthetic used. The patients were classified as having TNS if, following recovery from anaesthesia, there was pain in the buttocks, thighs and/or lower limbs. Results: In the levobupivacaine group, one patient (3.33%) experienced TNS, whereas in the lidocaine group, eight (26.6%) experienced TNS ( P=0.002). Maximum times to arrival of sensory blocks were shorter with lidocaine ( P<0.001). The levobupivacaine and lidocaine groups did not differ significantly in terms of the highest dermatome included in sensory block or motor block grade. Conclusion: After spinal anaesthesia with levobupivacaine, the incidence of TNS was much less than after lidocaine. However, it appears that TNS may occur in association with levobupivacaine. [ABSTRACT FROM AUTHOR]

Background: We investigated whether coadministration of lidocaine and dexmedetomidine would reduce brain injury following transient forebrain ischemia in rats to a greater extent than either drug alone. Methods: Adult male Sprague–Dawleyrats were anesthetized with halothane to maintain normocapnia and normoxia. Rats received subcutaneous injection of saline 1 ml/kg, lidocaine 10 mg/kg, dexmedetomidine 3 μg/kg, or lidocaine 10 mg/kg plus dexmedetomidine 3 μg/kg. Thirty minutes after the drug injection, forebrain ischemia was induced by hemorrhagic hypotension and occlusion of the bilateral carotid arteries, and was confirmed by isoelectric EEG. At the end of 10-min ischemia, rats were reperfused. The same dose of drugs was administered 3, 24, and 48 h after ischemia. Neurological examination was done at 1, 2, and 7 days after ischemia. Seven days after ischemia, the brain was stained with hematoxylin and eosin. We counted ischemic cells in the CA1 hippocampal region, striatum, and cerebral cortex. We also measured extracellular glutamate and norepinephrine concentration in hippocampal CA1 in the four groups. Results: As compared with saline-treated rats, rats receiving dexmedetomidine plus lidocaine showed less than neurological deficit scores at 2 and 7 days after ischemia, and had less ischemic cells in the CA1 region. However, administration of dexmedetomidine plus lidocaine did not alter the area under the glutamate concentration curve and norepinephrine concentration during ischemia in the CA1 region, compared with saline-treated rats. Conclusions: Our results suggest coadministration of lidocaine and dexmedetomidine improves the neurological outcome without alteration of glutamate and norepinephrine concentrations during forebrain ischemia in rats. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this prospective, randomised, blind study was to compare the evolution of spinal block produced with 50 mg lidocaine 10 mg/ml and 10 mg ropivacaine 5 mg/ml for outpatient knee arthroscopy. Methods: Thirty outpatients undergoing knee arthroscopy received 50 mg of lidocaine 10 mg/ml ( n=15) or 10 mg of ropivacaine 5 mg/ml ( n=15) intrathecally. The evolution of spinal block was recorded until home discharge, while the occurrence of transient neurologic symptoms (TNS) was evaluated through phone-call follow-ups. Results: The median onset time was 15 (10–21) min with lidocaine and 24 (11–37) min with ropivacaine ( P=0.109). Spinal lidocaine resulted in a faster resolution of sensory block [148 (130–167) min vs. 188 (146–231) ( P=0.022)], unassisted ambulation with crutches [176 (144–208) min vs. 240 (179–302) min ( P=0.014)], and voiding [208 (163–254) min vs. 293 (242–343) min ( P=0.001)] than ropivacaine. Recovery of motor function required 113 (95–131) min with lidocaine and 135 (87–183) with ropivacaine ( P=0.219). Six lidocaine patients reported TNS (40%) as compared with no patient receiving ropivacaine (0%) ( P=0.005). Conclusions: Spinal block produced with 10 mg ropivacaine 5 mg/ml is as effective as that produced by 50 mg of lidocaine 10 mg/ml. Recovery of unassisted ambulation and spontaneous voiding occurred earlier with lidocaine, but this was associated with a markedly higher incidence of TNS. [ABSTRACT FROM AUTHOR]

Background: Lidocaine has been used for spinal anaesthesia since 1948, seemingly without causing concern until recently. This study aimed at evaluating the feasibility of performing anorectal surgery in outpatient settings with low hypobaric lidocaine doses. Methods: Three groups of 50 patients, physical status ASA I–II, undergoing anorectal surgical procedures in a prone jack-knife position, received 3 ml (18 mg), 4 ml (24 mg) or 5 ml (30 mg) of hypobaric 0.6% lidocaine. Sensory and motor blockade, time until first urination, ambulation, complications and the need for analgesics were evaluated. Patients were followed until the third post-operative day. Results: Adequate sensory block was obtained in all patients. Blockade was significantly lower in Group 1. The level at 15 min was L1 with 3 ml, T11 with 4 ml and T10 with 5 ml. Only 24 patients presented a moderate motor block. There was no hypotension, nausea or vomiting, urine retention, transitory neurological symptom or post-dural puncture headache in any patients. There was one case of bradycardia with 4 ml and two cases with 5 ml. Conclusions: Hypobaric lidocaine predominantly provided a sensory block after injection in the prone jack-knife position. The smallest dose (3 ml=18 mg) provides sufficient analgesia with a lesser dispersion and a shorter duration. The major advantages were haemodynamic stability and a high degree of patient satisfaction. [ABSTRACT FROM AUTHOR]

Background: Spinal anesthesia with the local anesthetic lidocaine has come under scrutiny because it is associated with transient neurologic symptoms (TNS). Although TNS is not associated with either lidocaine concentration or dose, its incidence has never been examined with very small doses of hyperbaric spinal lidocaine in patients in the lithotomy position. We designed this study prospectively to compare the efficacy of low-dose 15 mg/ml with low-dose 20 mg/ml hyperbaric lidocaine in patients undergoing elective outpatient surgery in the lithotomy position. Methods: A total of 100 patients were randomized to receive either 30 mg of 15 mg/ml or the same dose of 20 mg/ml hyperbaric lidocaine. Lidocaine density at 37 °C is 1.0241 g/ml for the 15 mg/ml and 1.0260 g/ml for the 20 mg/ml solution. Patients were examined for motor block, sensory block, and block duration. Patients were contacted at 24, 48 and 72 h and questioned about their perceptions of pain after the spinal anesthesia with specific questions designed to diagnose TNS. Results: The spread of analgesia was the same with both solutions of lidocaine. Motor block was incomplete in all patients in both groups. TNS were not observed when low doses of both solutions of lidocaine with dextrose were used in these ambulatory patients in the lithotomy position. Conclusion: Hyperbaric lidocaine results in rapid recovery from sensory block and motor blockade. It may have advantages for patients in a day-case setting. No patients complained of TNS after discharge. [ABSTRACT FROM AUTHOR]

Background: A nerve stimulation-guided lateral sagittal infraclavicular block (LSIB) has been proven to be an effective block. The purpose of this study was to evaluate whether the use of ultrasound (US) guidance would further improve the block quality of LSIB. Methods: In a prospective manner, 80 adult patients scheduled for hand, wrist and forearm surgery were randomly allocated to US or nerve stimulation (NS) groups. A needle was inserted into a sagittal plane, 20° dorsally, until muscle twitches were observed in synchrony with the stimulation. In the US group, the block was performed using the same puncture site but under ultrasonic guidance. The final position of the needle was verified with the use of a nerve stimulator. A local anesthetic mixture of 20 ml of levobupivacaine, 5 mg/ml and 20 ml of lidocaine and 20 mg/ml with 5 μg/ml epinephrine (total 40 ml) was administered in both groups. Results: The block was successful in 37 patients in the NS group and 38 patients in the US group. Block efficacy was better in the US group than the group NS in radial nerve distribution at 20 min ( P<0.05). In the US group, there was a slight tendency toward better block density in other nerve areas also but these differences were not significant. Vascular puncture was noted in three patients in the NS group and none in the US group. Conclusions: The block success rate was high and comparable in both groups. There was a trend toward improved block quality in the US group, although not significant. [ABSTRACT FROM AUTHOR]

Background: The purpose of this study was to evaluate the clinical utility and block success rate of ‘lateral sagittal infraclavicular block (LSIB)’ in a large-scale clinical study. Methods: Adult patients scheduled for hand, wrist and forearm surgery between March 2005 and June 2007 were prospectively included into the study. Using a nerve stimulator LSIB was performed. In the LSIB technique the puncture site is immediately adjacent to the most medial point of the coracoid process and the anterior surface of the clavicula. The needle is inserted caudally in a sagittal plane, 20° dorsally (downwards), until muscle twitches are observed in synchrony with the stimulation. A Local anesthetic mixture of either 20 ml bupivacaine 5 mg/ml or 20 ml of levobupivacaine 5 mg/ml and 20 ml of lidocaine 20 mg/ml with 5 μg/ml epinephrine (total volume 40 ml) was administered following electrolocation of the median, radial or ulnar nerve. Results: Three-hundred and eighty patients were included into the study. Block was successful in 341 (89.7%) patients without any need for local anesthetic supplementation. We had complete failure in 17 (4.5%) patients and these patients received general anesthesia. Twenty-two (5.8%) patients needed either infiltration of local anesthetic at the site of skin incision or supplementation of the block at the axilla. No other complications other than vascular punctures − 25 patients (6.6%) – were observed. Conclusions: LSIB provided a clinically acceptable success rate and our results are in agreement with other studies assessing this approach. [ABSTRACT FROM AUTHOR]

Background: Post-ischemic administration of volatile anesthetics activates ischemia–reperfusion injury salvage process and decreases myocardial damage. However, the mechanisms underlying anesthetic post-conditioning and effects of lidocaine on it remain unclear. Here we report the cardioprotection of sevoflurane-induced post-conditioning and the effects of lidocaine on it. Methods: Isolated perfused rat hearts were exposed to 40 min of ischemia followed by 1 h of reperfusion. Volatile anesthetic post-conditioning was induced by 15 min of 3 vol% sevourane (1.5 minimum alveolar concentration) administered at the onset of reperfusion. In some experiments, lidocaine was coadministered with sevoflurane in different concentrations (2, 10 and 20 μg/ml). Infarct size was determined by dividing the total necrotic area of the left ventricle by the total left ventricular slice area (percent necrotic area). Results: Sevoflurane-induced post-conditioning signicantly improved post-ischemia functional recovery and decreased infarct size (47.3±5.6% in unprotected hearts vs. 18.6±3.1% in anesthetic post-conditioning, P<0.05). Sevourane-mediated cardioprotection was abolished by 20 μg/ml lidocaine. Conclusions: Sevourane-induced post-conditioning effectively protected myocardium against reperfusion damage and its cytoprotection was reversed by 20 μg/ml lidocaine. [ABSTRACT FROM AUTHOR]

The article presents a reprint of the article "Effect of Local Anaesthetics on Wound Healing: An Experimental Study with Special Reference to Carbocain," by Eric Nilsson and Bo Wendeberg, which appeared in the 1957 issue of the "Acta Anaesthesiologica Scandinavica." The study showed that the tissue toxicity of carbocain appeared to be too small and reflected only a slight difference in the tensile strength of the wounds. As compared with procaine, the results argued in favor of carbocain.

The article presents a reprint of the article "Lidocaine for Spinal Anesthesia," by Ernst Trier Mörch, Murray Kenneth Rosenberg and Aldo T. Truant, which appeared in the 1957 issue of the "Acta Anaesthesiologica Scandinavica." It describes the pharmacokinetics in the cerebrospinal fluid (CSF) of 5 percent lidocaine with 7.5 percent dextrose for spinal anesthesia. The study showed that the return of motor and sensory function was dependent more on the initial concentration of lidocaine.

Background: Lidocaine inhalation attenuates histamine-induced bronchoconstriction, as well as bronchoconstriction elicited by mechanical irritation. This effect could be mediated by direct effects on smooth muscle or by reflex attenuation. Therefore, we evaluated whether lidocaine attenuated the bronchial response of direct smooth muscle stimulation with methacholine.Methods: In 15 volunteers with bronchial hyperreactivity, a methacholine challenge was performed following the inhalation of lidocaine, dyclonine (which does not attenuate bronchial reactivity) or saline on three different days in a randomized, double-blind fashion. Lung function, response to methacholine, and lidocaine and dyclonine plasma concentrations were measured.Results: The inhaled methacholine concentration (PC20) necessary for a 20% decrease in the forced expiratory volume in 1 s (FEV1) was 8.8 +/- 6.1 mg/ml at the screening evaluation. The sensitivity to methacholine challenge (PC20) remained unchanged regardless of which solution was inhaled (9.1 +/- 7.5 mg/ml for lidocaine, 10.2 +/- 9.0 mg/ml for dyclonine and 9.8 +/- 8.3 mg/ml for saline; P = 0.58, means +/- standard deviation). Furthermore, the inhalation of all three solutions caused a significant decrease in FEV1 from baseline (P = 0.0007), with a significantly larger effect for dyclonine than lidocaine (P = 0.0153).Conclusions: Although both inhaled and intravenous lidocaine attenuates histamine-evoked bronchoconstriction, it does not alter the response to methacholine. Therefore, the attenuation of bronchial reactivity by lidocaine appears to be related solely to neurally mediated reflex attenuation, rather than to the attenuation of direct constriction of airway smooth muscle. [ABSTRACT FROM AUTHOR]

Background: Side-clamping of the ascending aorta during off-pump coronary artery bypass surgery (OPCAB) may be associated with a significant increase in systemic blood pressure which may rarely result in aortic dissection. We evaluated whether topical application of lidocaine on the ascending aorta could reduce the rise in systemic blood pressure during side-clamping of the aorta in OPCAB. Methods: Forty-four patients scheduled for OPCAB were randomly allocated to receive gauze soaked with 10 ml of 4% lidocaine ( n= 22) or normal saline ( n= 22) on the side-clamping site of the aorta. Sodium nitroprusside (SNP) was infused as necessary to maintain the systolic blood pressure at around 100 mmHg immediately prior to and during side-clamp of the aorta. The requirement and frequency of use of SNP, as well as haemodynamic variables, were recorded serially. Results: The number of patients requiring an SNP infusion and the average amount of infused SNP were significantly less in the lidocaine group. Systolic blood pressure increased significantly during side-clamping in the control group, but not in the lidocaine group. Conclusion: Topical application of lidocaine on the surface of the aorta is a simple and effective method to reduce the risk of a sudden increase in systemic blood pressure during side-clamping of the aorta. [ABSTRACT FROM AUTHOR]

Background: The use of propofol and adjuvants such as opioids, benzodiazepines and local anaesthetic agents, may provide adequate conditions for tracheal intubation without the need for neuromuscular blocking agents. In this randomized, double-blind study, intubating conditions after induction of anaesthesia with propofol, midazolam and fentanyl were compared with those after propofol, lignocaine and fentanyl. Methods: In 80 ASA I/II adult patients undergoing elective gynaecological surgery, intubating conditions were compared after induction of anaesthesia with a fentanyl 2 μg/kg, midazolam 0.03 mg/kg, propofol 2.5 mg/kg combination (group FMP) vs. a fentanyl 2 μg/kg, lignocaine 1.5 mg/kg, propofol 2.5 mg/kg combination (group FLP). Intubating conditions were assessed using a qualitative scoring system. Results: Intubation was successful in all patients in group FMP and in 87.5% of patients in group FLP; ( P= 0.021). Overall, intubating conditions were clinically acceptable in 77.5% and 55% of patients in group FMP and group FLP, respectively ( P= 0.033). Conclusion: We conclude that the fentanyl, midazolam, propofol combination more reliably provides acceptable conditions for intubation than the fentanyl, lignocaine, propofol combination. Intubation was successful in all patients receiving the fentanyl, midazolam, propofol combination. [ABSTRACT FROM AUTHOR]

Background: Local anesthetic containing epinephrine is commonly used in many operations for the main purpose of hemostasis. A randomized, controlled, prospective clinical trial was designed to find out hemodynamic changes after local infiltration of different concentrations and/or different dosages of epinephrine during functional endoscopic sinus surgery (FESS) under general anesthesia. Methods: One hundred and eight adult patients undergoing elective FESS under general anesthesia were randomly allocated into four groups. Group I received 2% lidocaine 2 ml with epinephrine (5 µg/ml); group II received 1% lidocaine 4 ml with epinephrine (2.5 µg/ml); group III received 1% lidocaine 4 ml with epinephrine (5 µg/ml); and group IV received 1% lidocaine 4 ml for local infiltration. Heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial pressure (MAP) were monitored continuously in the radial artery and recorded in 6 min: before infiltration (baseline), 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, and 6 min after local infiltration. The lowest blood pressure (BP) in this period was also recorded. Results: Significant hemodynamic changes, particularly a decrease in BP ( P < 0.001) with a slight increase in HR ( P < 0.001) at approximately 1.5 min and an increase in SBP at approximately 3 min ( P < 0.01) after local infiltration, were observed in group I, group II and group III compared with the baseline, but not in group IV. No significant hemodynamic differences were observed between group I, group II and group III at the same time points ( P > 0.05). Conclusion: Local infiltration of low-dose epinephrine causes temporary significant hemodynamic changes particularly a marked decrease in BP during FESS under general anesthesia. [ABSTRACT FROM AUTHOR]

Background: It is common today to use tumescent anaesthesia with large doses of lidocaine for liposuction. The purpose of the present study was to evaluate lidocaine plasma levels and objective and subjective symptoms during 20 h after tumescent anaesthesia with approximately 35 mg per kg bodyweight of lidocaine for abdominal liposuction. Methods: Three litres of buffered solution of 0.08% lidocaine with epinephrine was infiltrated subcutaneously over the abdomen in eight female patients during monitored intravenous (i.v.) light sedation. Plasma levels of lidocaine and signs of subjective and objective symptoms were recorded every 3 h for 20 h after liposuction. Results: Lidocaine 33.2 ± 1.8 mg/kg was given at a rate of 116 ± 11 ml/min. Peak plasma levels (2.3 ± 0.63 µg/ml) of lidocaine occurred after 5–17 h. No correlation was found between peak levels and dose per kg bodyweight or total amount of lidocaine infiltrated. One patient experienced tinnitus after 14 h when a plasma level of 3.3 µg/ml was recorded. Conclusion: Doses of lidocaine up to 35 mg/kg were sufficient for abdominal liposuction using the tumescent technique and gave no fluid overload or toxic symptoms in eight patients, but with this dose there is still a risk of subjective symptoms in association with the peak level of lidocaine that may appear after discharge. [ABSTRACT FROM AUTHOR]

The present study used the A-line ARX index, derived from auditory evoked potential measurements, to examine the effect of epidural lidocaine on the end-tidal concentration of desflurane during general anesthesia. Thirty ASA I–II patients scheduled for elective colorectal surgery were included and randomized, in a double-blinded fashion, to receive general anesthesia, and 15 ml of either 2% lidocaine (group GE, n = 15) or normal saline (group GS, n = 15) was administered epidurally with a maintenance infusion rate of 6 ml h−1. After a 10-min high-flow oxygen wash-in period, desflurane was titrated to a target A-line ARX index (AAI) of 20 ± 5. Epidural lidocaine reduced the end-tidal concentration of desflurane required to maintain an adequate clinical effect by 42% compared to general anesthesia alone (2.6% vs. 4.5%, respectively; P < 0.001). The initial mean value of AAI was 87.8 (range 78–99) in group GE and 88.13 (79–99) in group GS before general anesthesia induction, the AAI values were approximately 19.7 (15–25) in group GE and 20.2 (16–25) in group GS during anesthesia maintenance, and returned to 84.53 (77–98) in group GE and 86.87 (79–98) in group GS when the patients regained consciousness in the recovery room. No statistical difference in the AAI values was observed either before, during, or after emergence of anesthesia. No patient reported intraoperative awareness. Lower-than-expected concentrations of volatile anesthetics are sufficient to maintain appropriate a clinical anesthesia effect during combined general-epidural anesthesia under auditory-evoked potential monitoring. [ABSTRACT FROM AUTHOR]

Laryngo-tracheal lidocaine spray before intubation is associated with an increased risk of postoperative throat problems. Our study investigated the effect of additives contained in lidocaine spray on postoperative sore throat, hoarseness and dysphagia.We compared the incidence and severity of postoperative throat complications after laryngo-tracheal application of lidocaine spray (40 mg), lidocaine (40 mg) or normal saline as placebo during laryngoscopy with total intravenous anaesthesia in 122 ASA I–III patients aged 15–87 years in a double-blinded, placebo-controlled study. The incidence and severity of postoperative sore throat, hoarseness and dysphagia were evaluated on the day of and the day after surgery.Sore throat and dysphagia were significantly more severe after lidocaine spray was used than after lidocaine or placebo was used. However, there was no significant difference in the incidence or severity of postoperative sore throat, hoarseness or dysphagia between the lidocaine group and the placebo group throughout the study.These results suggest that additives in lidocaine spray, not lidocaine itself, contribute to the increase in postoperative throat problems. Therefore, lidocaine spray should be avoided to prevent these unnecessary complications. Our findings also confirm that laryngo-tracheal lidocaine application does not prevent sore throat, hoarseness or dysphagia after total intravenous anaesthesia. [ABSTRACT FROM AUTHOR]

Using a push-button device, we investigated whether visual or auditory response time would increase with increasing sedation, and assessed the responsiveness score of the Observer's Assessment of Alertness/Sedation (OAA/S) scale at the point of first loss of response to visual or auditory stimulation. In experiment 1 we applied visual and auditory stimulation to 19 patients as the propofol target plasma concentration (CPT) was increased to determine whether the visual or auditory response would be lost first. Thirty patients were each then infused with propofol, starting at a CPT of 0.3 µg ml−1 and increasing by increments of 0.2 µg ml−1, during which visual (experiment 2) or auditory (experiment 3) stimulation was applied when the effect-site concentration (CE) of propofol reached CPT. Visual response time (VRT), auditory response time (ART), CE and total amounts of propofol, and OAA/S score at the first loss of visual/auditory response were measured. Visual response disappeared earlier than auditory response in 84.2% of the patients. Visual response time and ART were linearly prolonged as the CE of propofol increased. The CE and total amounts of propofol at the first loss of visual response were 1.2 ± 0.4 µg ml−1 and 57.9 ± 16.7 mg, compared with 1.4 ± 0.5 µg ml−1 and 71.6 ± 26.1 mg, respectively, at the first loss of auditory response. The median (range) OAA/S scores at the first loss of visual and auditory response were 4 (3–4) and 3 (2–4), respectively. VRT and ART were linearly prolonged with increasing sedation. Visual response may be useful in monitoring conscious sedation. [ABSTRACT FROM AUTHOR]

Pain following spinal cord injury (SCI) is a therapeutic challenge. Only a few treatments have been assessed in randomized, controlled trials. The primary objective of the present study was to examine the analgesic effect of ketamine and lidocaine in a group of patients with neuropathic pain below the level of spinal cord injury. We also wanted to assess sensory abnormalities to see if this could help us to identify responders and if treatments resulted in changes of sensibility. Response to treatment, defined as 50% reduction in VAS-score during infusion, was recorded in 5/10 in the ketamine, 1/10 in the lidocaine and 0/10 in the placebo groups. Neither ketamine nor lidocaine changed temperature thresholds or assessments of mechanical; dynamic and static sensibility. Nor could these sensory assessments predict response to treatment in this setting. Lidocaine and particularly ketamine were associated with frequent side-effects. Ketamine but not lidocaine showed a significant analgesic effect in patients with neuropathic pain after spinal cord injury. The pain relief was not associated with altered temperature thresholds or other changes of sensory function. [ABSTRACT FROM AUTHOR]

Intravenous cannulation in children aged 6–12 years is less painful after a 90-min application of a Lidocaine/Prilocaine cream followed by a 30-min interval without cream, than cannulation immediately after a 60-min application. The i.v. cannulations in Group B were less painful than the cannulations in Group A (Mann­Whitney test, P = 0.01). There was no difference between the two groups as regards problems when performing the cannulations. I.v. cannulation after application of anaesthetic cream for 90 min followed by a 30-min interval is less painful than the widely used 60-min application directly followed by cannulation. [ABSTRACT FROM AUTHOR]

Background: This study investigated whether addition of 15 microg epinephrine plus 25 microg fentanyl to lidocaine spinal anesthesia for outpatient knee arthroscopy makes it possible to use a subanesthetic lidocaine dose. The aim was to assess the quality of anesthesia and the suitability of this protocol for outpatient knee arthroscopy.Methods: Seventy-five outpatients scheduled for knee arthroscopy were randomly assigned to one of three spinal anesthetic protocols: Group L10F25 received 10 mg of lidocaine plus 25 micro g fentanyl; Group L10F25E15 received 10 mg of lidocaine plus 25 microg fentanyl plus 15 microg epinephrine; and Group L20F25 received 20 microg lidocaine plus 25 microg fentanyl. Tourniquet pain and surgical pain were assessed using a visual analog scale. If spinal anesthesia was inadequate despite supplementary intravenous analgesia and sedation, the patient was converted to general anesthesia. Recovery times and side-effects in the early postoperative period were recorded.Results: The highest level of sensory block was above the T12 dermatome in all patients. Compared with the other groups, significantly more patients in Group L10F25 converted to general anesthesia. Group L10F25 had a significantly higher mean surgical pain score than the other groups. The mean tourniquet pain score was significantly higher in Group L20F25 than Group L10F25E15. Group L10F25E15 had a significantly shorter time to discharge than the other groups. Post-operative nausea and vomiting and drowsiness were more frequent in Group L10F25 than in the other groups.Conclusion: The combination of 10 mg lidocaine and 25 microg fentanyl plus 15 microg epinephrine provides adequate spinal anesthesia and has favorable recovery characteristics for outpatient knee arthroscopy. [ABSTRACT FROM AUTHOR]

Background: Neuropathic pain is often severe and resistant to pharmacological treatment. The aims of the present study were to assess the analgesic effect of ketamine and lidocaine and to investigate if measurement of different variables of sensibility could be used to identify responders. We also wanted to study if treatment resulted in changes of sensibility.Methods: Twelve patients with long-lasting peripheral neuropathic pain of traumatic origin were included. The effects of ketamine hydrochloride (Ketalar, Parke Davis) 0.4 mg/kg and lidocaine hydrochloride (Xylocain, Astra) 2.5 mg/kg were investigated. Saline was used as placebo. The intensity of continuous pain was measured by a visual analogue scale (VAS). Warm and cold perception as well as heat and cold pain thresholds were assessed. Sensibility to touch was also tested. Systemic plasma concentrations of lidocaine and ketamine were assessed.Results: The mean reduction in VAS-scores was 55%, 34% and 22% for ketamine, lidocaine and placebo, respectively. A significant difference was registered between ketamine and placebo (P = 0.009). Response to treatment (50% reduction in VAS-score during infusion) was recorded in 7/12 in the ketamine, 4/12 in the lidocaine and 2/12 in the placebo group. Quantitative sensory testing (QST) of thermal sensitivity and sensory tests for mechanical stimuli could not separate responders from non-responders and neither were the results from these assessments changed by the infusion of the drugs. Lidocaine and particularly ketamine were associated with frequent side-effects, the most common being somnolence and dizziness.Conclusion: Ketamine showed a significant analgesic effect. The clinical usefulness is, however, limited by disturbing side-effects. [ABSTRACT FROM AUTHOR]

Background: Rocuronium (ORG 9426) has been shown to have an onset of action more rapid than other nondepolarizing neuromuscular blocking agents and to provide intubating conditions similar to those of succinylcholine 60-90 s after administration. We compared the intubating conditions and hemodynamic changes after the administration of rocuronium 0.6 mg kg(-1) and lidocaine 1.5 mg kg(-1) with rocuronium alone and succinylcholine 60 and 90 s after administration.Methods: One hundred and twenty-five adult patients of ASA physical status I or II scheduled for elective surgery were randomly divided into five groups. After propofol administration in all patients, patients in group Su (succinylcholine), group R60 (rocuronium) and group RL60 (rocuronium-lidocaine) were intubated within 60 s, while groups RL90 and R90 were intubated 90 s after the administration of rocuronium and succinylcholine. Laryngoscopy was performed and intubating conditions were graded by an experienced anesthetist blind to the muscle relaxant allocation.Results: In this study, groups Su, RL60, R90 and RL90 had similar intubation scores, which were significantly better than that for group R60. Heart rate did not increase after intubation in groups Su, RL60 and RL90.Conclusion: The combination of lidocaine (1.5 mg kg(-1)) and low-dose rocuronium (0.6 mg kg(-1)) along with propofol is clinically equivalent to succinylcholine, improves intubating conditions in 60 s and effectively blocks increases in heart rate after intubation. [ABSTRACT FROM AUTHOR]

Background: This study compared the postoperative infusion of 1% lidocaine and 0.2% ropivacaine for continuous interscalene analgesia in patients undergoing open shoulder surgery.Methods: Forty patients undergoing open shoulder surgery received an interscalene brachial plexus block with 30 ml of either 1.5% lidocaine (n = 20) or 0.5% ropivacaine (n = 20), followed by a continuous patient-controlled interscalene analgesia with 1% lidocaine or 0.2% ropivacaine, respectively. A blinded observer recorded the quality of analgesia and recovery of motor function during the first 24 h of infusion.Results: Onset of the block occurred after 7.5 (5-40) min with lidocaine and 30 (10-60) min with ropivacaine (P = 0.0005). Postoperative pain intensity was higher with lidocaine than ropivacaine for the first 8 h of infusion. The ratio between boluses given and demanded from the pump was 0.5 (0.13-0.7) with lidocaine and 0.7 (0.4-1.0) with ropivacaine (P = 0.005). Rescue IV tramadol was required during the first 24 h of infusion by 16 patients of the lidocaine group (84%) and eight patients of the ropivacaine group (46%) (P = 0.05). At the 16 h and 24 h observation times a larger proportion of patients receiving ropivacaine had complete regression of motor block (70% and 95%) than patients receiving lidocaine (50% and 55%) (P = 0.05 and P = 0.013, respectively).Conclusions: Although 1% lidocaine can be effectively used for postoperative patient-controlled interscalene analgesia, 0.2% ropivacaine provides better pain relief and motor function. [ABSTRACT FROM AUTHOR]

Background: Anesthetic agents are known to influence functions of the immune system. Anesthetic drugs also support cancer progression by suppressing the activity of immune cells. In breast carcinoma an increase in expression of peripheral-type benzodiazepine receptors (PBR) and the gamma aminobutyl acid (GABA) level has been discovered. Therefore, an investigation of a direct influence of GABA-A agonist propofol, GABA-A and PBR-agonist etomidate, and the local anesthetic drug lidocaine, which can also bind to the GABA-A receptor and PBR, on migration of breast carcinoma cells was performed.Methods: MDA-MB-468 cells were incubated with anesthetic agents using clinically relevant concentrations (propofol 3, 6, 9 mg/l, etomidate 2, 3, 4 mg/l, and lidocaine 1.25, 2.5, 5 mg/l). Locomotion was investigated in a three-dimensional collagen matrix using time-lapse video microscopy and computer-assisted cell-tracking.Results: The percentage of migrating cells (57.4+/-1.9) as well as the velocity (0.22+/-0.09 microm/min) and distance migrated (89.4+/-66.8 microm/10 h) increased in the presence of propofol in a dose-dependent manner (up to 74.4+/-7.5, 0.30+/-0.09, 143.8+/-89.1, respectively) compared with the long chain triglyceride (LCT) control. In contrast, no influence of etomidate on the number of migrating cells could be observed. The velocity and distance migrated at 3 and 4 mg/l were found to be statistically significantly enhanced. Treatment with lidocaine caused an increase in the percentage of migrating cells (up to 75.0+/-5.6) in velocity dose dependently (up to 0.33+/-0.06) and in distance migrated (up to 151.5+/-92.9).Conclusion: These results show that different anesthetic drugs are able to modulate the migratory machinery of human breast carcinoma cells in vitro. [ABSTRACT FROM AUTHOR]

Background: Natural killer (NK) cells constitute an essential component of the innate immune system in the defence against infected and malignant cells. In this study the in vitro effect on NK cell activity of three different local anesthetics with different lipid solubility was investigated.Methods: Venous blood from seven healthy volunteers was incubated with three amide local anesthetics with three different concentrations of lipid solubility: lidocaine 0.50, 1.00 and 2.00 mg/ml, ropivacaine 0.375, 0.75 and 1.50 mg/ml, and bupivacaine 0.25, 0.50 and 1.00 mg/ml. After 1 h of incubation, mononuclear cells were isolated and cryopreserved until tested for NK cell cytotoxicity in a 4-h 51Cr-release assay against K-562 target cells. Natural killer cell cytotoxicity of mononuclear cells incubated with isotonic saline was used as the control.Results: A significant suppression in NK cell cytotoxicity was demonstrated for all three local anesthetic agents when the NK cell cytotoxicity was compared with the cytotoxicity estimated after incubation with the isotonic saline (P<0.004). Moreover a significant lipid solubility-dependent effect (P=0.0001) as well as an overall concentration-dependent effect (P<0.0001) on the NK cell cytotoxicity was found.Conclusion: The results of the present in vitro study suggest a negative association between the estimated NK cell cytotoxicity and the lipid solubility as well as the concentrations of the three local anesthetic agents tested. [ABSTRACT FROM AUTHOR]

Background and Objectives: pH adjustment and/or addition of hyaluronidase to local anesthetic drugs decrease the time to onset and prolong the duration of regional anesthetic techniques for ocular surgery. The objective of this study was to investigate whether these factors are effective also in sub-Tenon's block.Methods: Sixty patients were randomly assigned to four groups in a double blind, prospective fashion, and received 5.125 ml mixtures as follows: 2.5 ml lignocaine 2%, 2.5 ml bupivacaine 0.5% and 0.125 ml isotonic saline (group LB); 2.5 ml lignocaine 2%, 2.5 ml bupivacaine 0.5%, 15 IU hyaluronidase/ml and 0.125 ml isotonic saline (group LBH); 2.5 ml lignocaine 2%, 2.5 ml bupivacaine 0.5% and 0.125 ml sodium bicarbonate 8.4% (group LBpH); and 2.5 ml lignocaine 2%, 2.5 ml bupivacaine 0.5%, 15 IU hyaluronidase/ml and 0.125 ml sodium bicarbonate 8.4% (group LBHpH). This measurement was based on one quadrant sub-Tenon's block. Akinesia was assessed every 30 s.Results: No statistically significant differences were found between the groups regarding mean times to onset and to complete akinesia. Group LBH displayed a significantly lower frequency of patients experiencing pain and a lower need for rescue medication during surgery than the other groups.Conclusion: pH adjustment and/or addition of hyaluronidase to a mixture of lignocaine and bupivacaine did not shorten the time to onset of akinesia following sub-Tenon's technique. However, the addition of hyaluronidase was associated with a lower fraction of patients experiencing pain during surgery. [ABSTRACT FROM AUTHOR]

Purpose: Each of the freely available local analgesic agents may be used, alone or in combination, with or without hyaluronidase, epinephrine and sodium bicarbonate for peribulbar block analgesia (PBA). A prospective audit of four solutions was undertaken to rationalize choice of local analgesic agent for PBA.Methods: A randomized, prospective study on 200 middle-aged to elderly patients undergoing cataract extraction was undertaken to compare the efficacy of: (1) bupivacaine 0.5% (bup 0.5% plain); (2) bupivacaine 0.5% plus hyaluronidase 100 i.u. ml-1 (bup 0.5% hyalase); (3) lidocaine 2% plus epinephrine 1:200 000 (lido 2% epi); or (4) a mixture of lidocaine 2% and bupivacaine 0.5% (2:3 volume per volume mix) containing hyaluronidase 25 i.u. ml-1 (lido/bup/hyalase). A standardized deep peribulbar block technique, akinesia scoring system (each 5 minx4), and supplemental protocol was followed. Onset of block and supplementation rates to achieve akinesia were recorded by a blinded observer; the requirement for augmentation with topical oxybuprocaine or subconjunctival lidocaine during surgery and the time from first PBA injection to the completion of surgery (the duration of surgical access) were also recorded.Results: Groups (N=50) were comparable. Akinesia scores were similar after each agent at 5 min, better with lido 2% epi compared with bup 0.5% plain at 10 min (P<0.05), and better with bup 0.5% hyalase, lido 2% epi, and lido/bup/hyalase, than with bup 0.5% plain at 15 min (P<0.01, <0.01, <0.05, respectively) and at 20 min (P<0.05, <0.05, <0.025, respectively). The supplementation rate at 5 min was least with lido 2% epi, greater with bup 0.5% plain (P<0.01) and bup 0.5% hyalase (P<0.0005) and greatest with lido/bup/hyalase (P<0.0005), but similar in each group at 10, 15 and 20 min. Overall, those given lido 2% epi required the least number of supplemental injections to achieve globe akinesia. Mean supplemental injectate volumes, augmentation rates during surgery and the durations of surgical access provided by each agent were similar.Conclusion: All four agents provided adequate analgesia during cataract extraction lasting approximately 95-100 min after PBA injection. Lido 2% epi demonstrated most rapid onset and required least number of injections to establish block. A hyaluronidase effect was evident only after 15 min in the bup 0.5% hyalase and lido/bup/hyalase groups. Bup 0.5% plain was overall the least satisfactory, and the greatest supplementation rate occurred with lido/bup/hyalase, suggesting that either lido 2% epi or bup 0.5% hyalase are the most suitable of the agents tested for this type of surgery. [ABSTRACT FROM AUTHOR]

Background: Slow-release formulations of local anaesthetics may produce nerve blocks of long duration. The present study aimed at investigating the in vitro and in vivo properties of a polar lipid formulation for slow release of lignocaine and the effects on nerve block duration by inclusion of dexamethasone into the system. Methods: In vitro release of lignocaine from the lipid formulation was studied in a US Pharmacopoeia rotating apparatus. Sciatic nerve blocks were induced in rats by 0.1 ml of test formulations containing lignocaine HCl 20 mg · ml-1 in aqueous solution, lignocaine base 20, 100 or 200 mg · ml-1 in lipid formulation or the last formulation with dexamethasone 0.05, 0.5 or 5 mg · ml-1. The durations of sensory and motor block and the arterial blood concentrations of lignocaine were investigated. Results: In vitro there was a sustained release of lignocaine from the lipid formulation, with 50% release at around 48 h. In vivo lignocaine base 20 mg · ml-1 in lipid formulation produced sciatic nerve blocks of significantly shorter duration than lignocaine HCl 20 mg · ml-1 in aqueous solution, while lignocaine base 100 and 200 mg · ml-1 in lipid formulation produced blocks lasting two and three times longer, respectively, than the lignocaine HCl solution. Addition of dexamethasone did not affect the duration of nerve block. Following administration of lignocaine base 200 mg · ml-1 in lipid formulation, as compared to lignocaine HCl 20 mg · ml-1 in aqueous solution, the maximal blood concentration of lignocaine was only three times higher in spite of the ten-fold difference in dose, and the mean terminal half-life was three times longer, reflecting the slow release from the formulation. Conclusions: Our findings indicate that lignocaine base in polar lipids acts as a slow-release preparation of local anaesthetic both in vitro and in vivo. [ABSTRACT FROM AUTHOR]