Perfil de utilização de anestésicos locais de uma cidade brasileira com ênfase em diabéticos / Profile of use of local anesthetics in a Brazilian city with emphasis on diabetics

Objetivo: avaliar o conhecimento de cirurgiões-dentistas que trabalham em consultórios particulares de Palmas, Tocantins, quanto à utilização de anestésicos locais em pacientes portadores de diabetes mellitus. Materiais e método: trata-se de um estudo descritivo qualitativo, aprovado pelo Comitê de Ética em Pesquisa da FAMERP de São José do Rio Preto, sob o protocolo 032/2007 e CAAE: 0065.0.000.140-07, respeitando-se a Resolução 466/12, do Conselho Nacional de Saúde. A coleta de dados foi realizada por meio da aplicação de um questionário, utilizando um formulário estruturado. Resultados: de 113 participantes, 47 (41,6%) eram do sexo masculino e 66 (58,4%) do sexo feminino, com idade média de 35 anos. O anestésico mais utilizado pelos cirurgiões-dentistas avaliados foi a lidocaína 2% + adrenalina 1:100.000 (53,1%), o qual também é o mais utilizado para pacientes diabéticos controlados (64,6%). Quanto à variedade de anestésicos, 47,8% dos avaliados relataram possuir somente 3 tipos de anestésicos no consultório e que 83,2% nunca presenciaram nenhum problema decorrente do uso de anestésico. Além disso, 65,5% relataram não participar de cursos para atualização de conhecimentos, sendo que 53,1% mostraram-se insatisfeitos com o ensino de anestesiologia que receberam na graduação. Conclusão: observou-se que os cirurgiões-dentistas do atendimento odontológico particular de Palmas precisam de uma reciclagem profissional, a fim de atualizarem conhecimentos adquiridos na graduação sobre indicação e utilização de anestésicos locais em tratamentos odontológicos de pacientes com necessidades especiais, com ênfase em pacientes portadores de diabetes mellitus.(AU)

Objective: to evaluate the knowledge of dentists who work in private offices in Palmas, Tocantins, regarding the use of local anesthetics in patients with diabetes mellitus. Materials and method: this research is a qualitative descriptive study, approved by the Research Ethics Committee of FAMERP from São José do Rio Preto, under protocol number 032/2007 and CAAE: 0065.0.000.140-07 in compliance with the Resolution 466/12 of the National Health Council. Data collection was performed through the application of a questionnaire, using a structured form. Results: 47 (41.6%) out of 113 participants were male and 66 (58.4%) female, with an average age of 35 years old. The anesthetic most used by the dentists evaluated was lidocaine 2% + adrenaline 1: 100,000 (53.1%) which is also the most used for controlled diabetic patients (64.6%). As for the variety of anesthetics, 47.8% of those evaluated reported having only 3 types of anesthetics in the office and that 83.2% never saw any problems resulting from the use of anesthetics. Furthermore, 65.5% reported not participating in courses to update knowledge and 53.1% were dissatisfied with the teaching of anesthesiology they received during graduation. Conclusion: it was observed that dentists who work in private dental offices in Palmas need a professional retraining in order to update knowledge acquired during graduation on the indication and use of local anesthetics in dental treatments for patients with special needs, with an emphasis on patients with diabetes mellitus.(AU)

Safety of local anesthetics

Abstract Local anesthetics are essential medications for the conduction of dermatological procedures. They stop the depolarization of nerve fibers and are divided into two main categories, the amide and ester types. Systemic toxicity with reflex on the central nervous and cardiovascular systems is their most feared adverse reactions, and the anaphylactic reaction is the most concerning one. Although potentially fatal, these events are extremely rare, so local anesthetics are considered safe for use in in-office procedures.

Resistance to local anesthesia in people with the Ehlers-Danlos Syndromes presenting for dental surgery

BACKGROUND: People with the Ehlers-Danlos Syndromes (EDS), a group of heritable disorders of connective tissue, often report experiencing dental procedure pain despite local anesthetic (LA) use. Clinicians have been uncertain how to interpret this apparent LA resistance, as comparison of EDS and non-EDS patient experience is limited to anecdotal evidence and small case series. The primary goal of this hypothesis-generating study was to investigate the recalled adequacy of pain prevention with LA administered during dental procedures in a large cohort of people with and without EDS. A secondary exploratory aim asked people with EDS to recall comparative LA experiences. METHODS: We administered an online survey through various social media platforms to people with EDS and their friends without EDS, asking about past dental procedures, LA exposures, and the adequacy of procedure pain prevention. Among EDS respondents who both received LA and recalled the specific LA used, we compared agent-specific pain prevention for lidocaine, procaine, bupivacaine, mepivacaine, and articaine. RESULTS: Among the 980 EDS respondents who had undergone a dental procedure LA, 88% (n = 860) recalled inadequate pain prevention. Among 249 non EDS respondents only 33% (n = 83) recalled inadequate pain prevention (P < 0.001 compared to EDS respondents). The agent with the highest EDS-respondent reported success rate was articaine (30%), followed by bupivacaine (25%), and mepivacaine (22%). CONCLUSIONS: EDS survey respondents reported nearly three times the rate of LA non-response compared to non-EDS respondents, suggesting that LAs were less effective in preventing their pain associated with routine office dental procedures.

Myoclonus of ipsilateral upper extremity after ultrasound-guided supraclavicular brachial plexus block with mepivacaine / 대한마취과학회지

No abstract available.

Lipid emulsion inhibits vasodilation induced by a toxic dose of bupivacaine by suppressing bupivacaine-induced PKC and CPI-17 dephosphorylation but has no effect on vasodilation induced by a toxic dose of mepivacaine

BACKGROUND: The goal of this in vitro study was to investigate the effect of lipid emulsion on vasodilation caused by toxic doses of bupivacaine and mepivacaine during contraction induced by a protein kinase C (PKC) activator, phorbol 12,13-dibutyrate (PDBu), in an isolated endothelium-denuded rat aorta. METHODS: The effects of lipid emulsion on the dose-response curves induced by bupivacaine or mepivacaine in an isolated aorta precontracted with PDBu were assessed. In addition, the effects of bupivacaine on the increased intracellular calcium concentration ([Ca²⁺]ᵢ) and contraction induced by PDBu were investigated using fura-2 loaded aortic strips. Further, the effects of bupivacaine, the PKC inhibitor GF109203X and lipid emulsion, alone or in combination, on PDBu-induced PKC and phosphorylation-dependent inhibitory protein of myosin phosphatase (CPI-17) phosphorylation in rat aortic vascular smooth muscle cells (VSMCs) was examined by western blotting. RESULTS: Lipid emulsion attenuated the vasodilation induced by bupivacaine, whereas it had no effect on that induced by mepivacaine. Lipid emulsion had no effect on PDBu-induced contraction. The magnitude of bupivacaine-induced vasodilation was higher than that of the bupivacaine-induced decrease in [Ca²⁺]ᵢ. PDBu promoted PKC and CPI-17 phosphorylation in aortic VSMCs. Bupivacaine and GF109203X attenuated PDBu-induced PKC and CPI-17 phosphorylation, whereas lipid emulsion attenuated bupivacaine-mediated inhibition of PDBu-induced PKC and CPI-17 phosphorylation. CONCLUSIONS: These results suggest that lipid emulsion attenuates the vasodilation induced by a toxic dose of bupivacaine via inhibition of bupivacaine-induced PKC and CPI-17 dephosphorylation. This lipid emulsion-mediated inhibition of vasodilation may be partly associated with the lipid solubility of local anesthetics.

Lipid emulsion inhibits vasodilation induced by a toxic dose of bupivacaine by suppressing bupivacaine-induced PKC and CPI-17 dephosphorylation but has no effect on vasodilation induced by a toxic dose of mepivacaine

BACKGROUND: The goal of this in vitro study was to investigate the effect of lipid emulsion on vasodilation caused by toxic doses of bupivacaine and mepivacaine during contraction induced by a protein kinase C (PKC) activator, phorbol 12,13-dibutyrate (PDBu), in an isolated endothelium-denuded rat aorta. METHODS: The effects of lipid emulsion on the dose-response curves induced by bupivacaine or mepivacaine in an isolated aorta precontracted with PDBu were assessed. In addition, the effects of bupivacaine on the increased intracellular calcium concentration ([Ca²⁺]ᵢ) and contraction induced by PDBu were investigated using fura-2 loaded aortic strips. Further, the effects of bupivacaine, the PKC inhibitor GF109203X and lipid emulsion, alone or in combination, on PDBu-induced PKC and phosphorylation-dependent inhibitory protein of myosin phosphatase (CPI-17) phosphorylation in rat aortic vascular smooth muscle cells (VSMCs) was examined by western blotting. RESULTS: Lipid emulsion attenuated the vasodilation induced by bupivacaine, whereas it had no effect on that induced by mepivacaine. Lipid emulsion had no effect on PDBu-induced contraction. The magnitude of bupivacaine-induced vasodilation was higher than that of the bupivacaine-induced decrease in [Ca²⁺]ᵢ. PDBu promoted PKC and CPI-17 phosphorylation in aortic VSMCs. Bupivacaine and GF109203X attenuated PDBu-induced PKC and CPI-17 phosphorylation, whereas lipid emulsion attenuated bupivacaine-mediated inhibition of PDBu-induced PKC and CPI-17 phosphorylation. CONCLUSIONS: These results suggest that lipid emulsion attenuates the vasodilation induced by a toxic dose of bupivacaine via inhibition of bupivacaine-induced PKC and CPI-17 dephosphorylation. This lipid emulsion-mediated inhibition of vasodilation may be partly associated with the lipid solubility of local anesthetics.

Mepivacaine-induced intracellular calcium increase appears to be mediated primarily by calcium influx in rat aorta without endothelium / 대한마취과학회지

BACKGROUND: Mepivacaine induces contraction or decreased blood flow both in vivo and in vitro. Vasoconstriction is associated with an increase in the intracellular calcium concentration ([Ca2+]i). However, the mechanism responsible for the mepivacaine-evoked [Ca2+]i increase remains to be determined. Therefore, the objective of this in vitro study was to examine the mechanism responsible for the mepivacaine-evoked [Ca2+]i increment in isolated rat aorta. METHODS: Isometric tension was measured in isolated rat aorta without endothelium. In addition, fura-2 loaded aortic muscle strips were illuminated alternately (48 Hz) at two excitation wavelengths (340 and 380 nm). The ratio of F340 to F380 (F340/F380) was regarded as an amount of [Ca2+]i. We investigated the effects of nifedipine, 2-aminoethoxydiphenylborate (2-APB), gadolinium chloride hexahydrate (Gd3+), low calcium level and Krebs solution without calcium on the mepivacaine-evoked contraction in isolated rat aorta and on the mepivacaine-evoked [Ca2+]i increment in fura-2 loaded aortic strips. We assessed the effect of verapamil on the mepivacaine-evoked [Ca2+]i increment. RESULTS: Mepivacaine produced vasoconstriction and increased [Ca2+]i. Nifedipine, 2-APB and low calcium attenuated vasoconstriction and the [Ca2+]i increase evoked by mepivacaine. Verapamil attenuated the mepivacaine-induced [Ca2+]i increment. Calcium-free solution almost abolished mepivacaine-induced contraction and strongly attenuated the mepivacaineinduced [Ca2+]i increase. Gd3+ had no effect on either vasoconstriction or the [Ca2+]i increment evoked by mepivacaine. CONCLUSIONS: The mepivacaine-evoked [Ca2+]i increment, which contributes to mepivacaine-evoked contraction, appears to be mediated mainly by calcium influx and partially by calcium released from the sarcoplasmic reticulum.

Comparison of dexmedetomidine and epinephrine as an adjuvant to 1% mepivacaine in brachial plexus block / 대한마취과학회지

BACKGROUND: Dexmedetomidine extends the duration of nerve block when administered perineurally together with local anesthetics by central and/or peripheral action. In this study, we compared the duration of nerve block between dexmedetomidine and epinephrine as an adjuvant to 1% mepivacaine in infraclavicular brachial plexus block. METHODS: Thirty patients, scheduled for upper limb surgery were assigned randomly to 3 groups of 10 patients each. We performed brachial plexus block using a nerve stimulator. In the control group (group C), patients received 40 ml of 1% mepivacaine. In group E, patients received 40 ml of 1% mepivacaine containing 200 microg of epinephrine as an adjuvant. In group D, patients received 40 ml of 1% mepivacaine containing 1 microg/kg of dexmedetomidine as an adjuvant. Sensory block duration, motor block duration, time to sense pain, and onset time were assessed. We also monitored blood pressure, heart rate, oxygen saturation and bispectral index. RESULTS: In group D and group E, sensory block duration, motor block duration and time to sense first pain were prolonged significantly compared to group C. However, there was no significant difference between group D and group E. CONCLUSIONS: Perineural 1 microg/kg of dexmedetomidine similarly prolonged nerve block duration compared to 200 microg of epinephrine, but slowed heart rate. Thus, dexmedetomidine is expected to be a good alternative as an adjuvant to local anesthesia in patients who are cautioned against epinephrine.

Feasibility of Early and Repeated Low-dose Interscalene Brachial Plexus Block for Residual Pain in Acute Cervical Radiculopathy Treated with NSAIDS

BACKGROUND: To improve residual pain management in acute cervical radiculopathy treated with NSAIDs, the feasibility of early and repeated low-dose interscalene brachial plexus block (IS-BPB) needs to be assessed. METHODS: This was a prospective study on patients receiving NSAIDs (loxoprofen) for cervical radiculopathy of or = 70 (severe pain; SE group) were compared to the controls receiving NSAIDs. RESULTS: A total of 316 IS-BPBs were performed in the intervention group. There was a significant difference in the decline in the VAS from week 0 to week 3 in the MM and SE groups (P < 0.05); however, from week 3 to week 4, the therapeutic effect exhibited no significant difference. Thirteen patients at week 2 (15.5%; MM: 27.7%; SE: 0%), 43 at week 3 (51.2%; MM: 83.0%; SE: 10.8%), and 47 at week 4 (56.0%; MM: 85.1%; SE: 18.9%) achieved a VAS score of < or = 20. Patient satisfaction was high, and the decrease in VAS scores in both groups was significant (P < 0.05) compared to the controls. CONCLUSIONS: Weekly, low-dose, USG-guided IS-BPB can be implemented for early pain relief in acute cervical radiculopathy, with high patient satisfaction.

Lidocaine anaphylaxis and lidocaine-specific immunoglobulin E measurement

Although local anesthetics can cause adverse drug reactions (ADRs), most ADRs to local anesthetics are from vasovagal, toxic, or anxiety reactions, while immunoglobulin E (IgE)-mediated anaphylaxis is extremely rare. We report a case of IgE-mediated anaphylactic reaction to lidocaine. A 27-year-old male patient who had two episodes of anaphylactic reactions after local injection of lidocaine was referred to our clinic for the safe use of local anesthetics for the subsequent dental procedure. Skin prick and intradermal tests were performed with amide local anesthetics; lidocaine, bupivacaine, mepivacaine, and ropivacaine. Lidocaine and mepivacaine showed positive response in prick test, and lidocaine, mepivacaine, and bupivacaine showed positive reactions in intradermal test. Only ropivacaine showed negative response both in prick and in intradermal test, and the patient was successfully treated with it. To detect serum-specific IgE, we prepared lidocaine-human serum albumin (HSA) conjugate. Enzyme-linked immunosorbent assay result showed high level of specific IgE to lidocaine-HSA conjugate in serum of the patient. This case suggests that local anesthetics can elicit specific IgE-mediated allergic reactions, and both skin prick and intradermal test should be performed in case of suspected IgE-mediated allergic response to local anesthetics.

Effect of stellate ganglion block on laryngopharyngeal reflux disease / 대한마취과학회지

BACKGROUND: Laryngopharyngeal reflux (LPR) disease has many symptoms such as globus pharyngeus, excessive throat clearing and hoarseness. The aim of this study was to investigate the effect of stellate ganglion block (SGB) in addition to proton pump inhibitors (PPI) on LPR. METHODS: Fifty patients complaining of more than 3 typical LPR symptoms for over 3 months were enrolled in the study. The P group took PPI for 8 weeks. The SP group took PPI and interwent a series of 8 SGB procedure once a week during the period of treatment. The blocks were performed one at a time unilaterally on the right and left stellate ganglions by injecting 1% mepivacaine 6 ml. We evaluated the reflux symptom index (RSI) before treatment and following 4 weeks and 8 weeks of treatment in both groups. RESULTS: After 4 weeks of treatment, the RSI of the P group decreased, but not significantly, to 16.6 +/- 6.8 compared with the baseline value of 19.2 +/- 2.7 (P = 0.093), whereas the RSI of the SP group decreased significantly to 9.8 +/- 3.3 compared with the baseline value of 19.0 +/- 4.7 (P = 0.000). After 8 weeks of treatment, the RSI of the P group decreased significantly to 13.7 +/- 6.7 (P = 0.001) and the RSI of the SP group also decreased significantly to 7.7 +/- 3.4 (P = 0.000). There were significant differences in the RSI between the two groups after 4 weeks (P = 0.000) and 8 weeks (P = 0.001) of treatment. CONCLUSIONS: The symptoms of LPR improved earlier when PPI therapy was combined with SGB compared with PPI therapy alone.

Lipid emulsion-mediated reversal of toxic-dose aminoamide local anesthetic-induced vasodilation in isolated rat aorta / 대한마취과학회지

BACKGROUND: Intravenous lipid emulsion has been used to treat systemic toxicity of local anesthetics. The goals of this in vitro study were to determine the ability of two lipid emulsions (Intralipid(R) and Lipofundin(R) MCT/LCT) to reverse toxic dose local anesthetic-induced vasodilation in isolated rat aortas. METHODS: Isolated endothelium-denuded aortas were suspended for isometric tension recording. Vasodilation was induced by bupivacaine (3 x 10(-4) M), ropivacaine (10(-3) M), lidocaine (3 x 10(-3) M), or mepivacaine (7 x 10(-3) M) after precontraction with 60 mM KCl. Intralipid(R) and Lipofundin(R) MCT/LCT were then added to generate concentration-response curves. We also assessed vasoconstriction induced by 60 mM KCl, 60 mM KCl with 3 x 10(-4) M bupivacaine, and 60 mM KCl with 3 x 10(-4) M bupivacaine plus 1.39% lipid emulsion (Intralipid(R) or Lipofundin(R) MCT/LCT). RESULTS: The two lipid emulsions reversed vasodilation induced by bupivacaine, ropivacaine, and lidocaine but had no effect on vasodilation induced by mepivacaine. Lipofundin(R) MCT/LCT was more effective than Intralipid(R) in reversing bupivacaine-induced vasodilation. The magnitude of lipid emulsion-mediated reversal of vasodilation induced by high-dose local anesthetics was as follows (from highest to lowest): 3 x 10(-4) M bupivacaine-induced vasodilation, 10(-3) M ropivacaine-induced vasodilation, and 3 x 10(-3) M lidocaine-induced vasodilation. CONCLUSIONS: Lipofundin(R) MCT/LCT-mediated reversal of bupivacaine-induced vasodilation was greater than that of Intralipid(R); however, the two lipid emulsions equally reversed vasodilation induced by ropivacaine and lidocaine. The magnitude of lipid emulsion-mediated reversal of vasodilation appears to be correlated with the lipid solubility of the local anesthetic.

Minimum effective volume of mepivacaine for ultrasound-guided supraclavicular block / 대한마취과학회지

BACKGROUND: The aim of this study was to estimate the minimum effective volume (MEV) of 1.5% mepivacaine for ultrasound-guided supraclavicular block by placing the needle near the lower trunk of brachial plexus and multiple injections. METHODS: Thirty patients undergoing forearm and hand surgery received ultrasound-guided supraclavicular block with 1.5% mepivacaine. The initial volume of local anesthetic injected was 24 ml, and local anesthetic volume for the next patient was determined by the response of the previous patient. The next patient received a 3 ml higher volume in the case of the failure of the previous case. If the previous block was successful, the next volume was 3 ml lower. MEV was estimated by the Dixon and Massey up and down method. MEV in 95, 90, and 50% of patients (MEV95, MEV90, and MEV50) were calculated using probit transformation and logistic regression. RESULTS: MEV95 of 1.5% mepivacaine was 17 ml (95% confidence interval [CI], 13-42 ml), MEV90 was 15 ml (95% CI, 12-34 ml), and MEV50 was 9 ml (95% CI, 4-12 ml). Twelve patients had a failed block. Three patients received general anesthesia. Nine patients could undergo surgery with sedation only. Only one patient showed hemi-diaphragmatic paresis. CONCLUSIONS: MEV95 was 17 ml, MEV90 was 15 ml, and MEV50 was 9 ml. However, needle location near the lower trunk of brachial plexus and multiple injections should be performed.

Lipid Emulsions Enhance the Norepinephrine-Mediated Reversal of Local Anesthetic-Induced Vasodilation at Toxic Doses

PURPOSE: Intravenous lipid emulsions have been used to treat the systemic toxicity of local anesthetics. The goal of this in vitro study was to examine the effects of lipid emulsions on the norepinephrine-mediated reversal of vasodilation induced by high doses of levobupivacaine, ropivacaine, and mepivacaine in isolated endothelium-denuded rat aorta, and to determine whether such effects are associated with the lipid solubility of local anesthetics. MATERIALS AND METHODS: The effects of lipid emulsions (0.30, 0.49, 1.40, and 2.61%) on norepinephrine concentration-responses in high-dose local anesthetic (6x10-4 M levobupivacaine, 2x10-3 M ropivacaine, and 7x10-3 M mepivacaine)-induced vasodilation of isolated aorta precontracted with 60 mM KCl were assessed. The effects of lipid emulsions on local anesthetic- and diltiazem-induced vasodilation in isolated aorta precontracted with phenylephrine were also assessed. RESULTS: Lipid emulsions (0.30%) enhanced norepinephrine-induced contraction in levobupivacaine-induced vasodilation, whereas 1.40 and 2.61% lipid emulsions enhanced norepinephrine-induced contraction in both ropivacaine- and mepivacaine-induced vasodilation, respectively. Lipid emulsions (0.20, 0.49 and 1.40%) inhibited vasodilation induced by levobupivacaine and ropivacaine, whereas 1.40 and 2.61% lipid emulsions slightly attenuated mepivacaine (3x10-3 M)-induced vasodilation. In addition, lipid emulsions attenuated diltiazem-induced vasodilation. Lipid emulsions enhanced norepinephrine-induced contraction in endothelium-denuded aorta without pretreatment with local anesthetics. CONCLUSION: Taken together, these results suggest that lipid emulsions enhance the norepinephrine-mediated reversal of local anesthetic-induced vasodilation at toxic anesthetic doses and inhibit local anesthetic-induced vasodilation in a manner correlated with the lipid solubility of a particular local anesthetic.

Comparison of ultrasound-guided supraclavicular block according to the various volumes of local anesthetic / 대한마취과학회지

BACKGROUND: The ultrasound guidance in regional nerve blocks has recently been introduced and gaining popularity. Ultrasound-guided supraclavicular block has many advantages including the higher success rate, faster onset time, and fewer complications. The aim of this study was to examine the clinical data according to the varied volume of local anesthetics in the ultrasound-guided supraclavicular block. METHODS: One hundred twenty patients were randomized into four groups, according to the local anesthetic volume used: Group 35 (n = 30), Group 30 (n = 30), Group 25 (n = 30), and Group 20 (n = 30). Supraclavicular blocks were performed with 1% mepivacaine 35 ml, 30 ml, 25 ml, and 20 ml, respectively. The success rate, onset time, and complications were checked and evaluated. RESULTS: The success rate (66.7%) was lower in Group 20 than that of Group 35 (96.7%) (P < 0.05). The average onset times of Group 35, Group 30, Group 25, and Group 20 were 14.3 +/- 6.9 min, 13.6 +/- 4.5 min, 16.7 +/- 4.6 min, and 16.5 +/- 3.7 min, respectively. There were no significant differences. Horner's syndrome was higher in Group 35 (P < 0.05). CONCLUSIONS: In conclusion, we achieved 90% success rate with 30 ml of 1% mepivacaine. Therefore, we suggest 30 ml of local anesthetic volume for ultrasound-guided supraclavicular block.

Eficácia da articaína, da lidocaína e da mepivacaína associadas à epinefrina em pacientes com pulpite irreversível em molares mandibulares / Efficacy of articaine, of lidocaine and mepivacaine in patients associated with irreversible pulpitis in mandibular molars

O objetivo deste estudo foi comparar a eficácia anestésica da articaína 4%, da lidocaína 2% e da mepivacaína 2%, todas associadas à epinefrina 1:100.000, durante pulpectomia em pacientes com pulpite irreversível em molares mandibulares. Sessenta e seis voluntários do Setor de Urgência da Faculdade de Odontologia da Universidade de São Paulo receberam, aleatoriamente, 3,6ml de um dos anestésicos locais para o bloqueio convencional do nervo alveolar inferior (NAI). No caso de falha do bloqueio, foram administrados 3,6ml da mesma solução como injeção complementar no ligamento periodontal. O sinal subjetivo de anestesia do lábio, a presença de anestesia pulpar e ausência de dor durante a pulpectomia foram avaliados, respectivamente, por indagação ao paciente, por meio do aparelho estimulador pulpar elétrico (pulp tester) e por uma escala analógica verbal. A análise estatística foi realizada por meio dos testes Qui-quadrado, Kruskal Wallis e Razão de Verossimilhancas. Todos os pacientes reportaram anestesia no lábio após o bloqueio do NAI. A mepivacaína apresentou valores superiores (68,2%) para a anestesia pulpar após o bloqueio do NAI e a lidocaína (90%) após a injeção no ligamento periodontal. A mepivacaína apresentou valores superiores para a analgesia (72,7%) após o bloqueio no NAI e a lidocaína (90%) após a injeção no ligamento periodontal. Após a falha do bloqueio do NAI, a dor na câmara pulpar foi a mais frequente e após a falha da injeção no ligamento periodontal, a dor no canal. No entanto, essas diferenças não foram estatisticamente significantes. Portanto as três soluções anestésicas locais se comportam de forma semelhante e não apresentam efetivo controle da dor no tratamento da pulpite irreversível em molares mandibulares.

The aim of this study was to compare the anesthetic efficacy of 4% articaine, lidocaine 2% and 2% mepivacaine, all associated with epinephrine 1:100,000 during pulpectomy in patients with irreversible pulpitis in mandibular molars. Sixty-six volunteers Sector Emergency Faculty of Dentistry, Universidade de São Paulo randomly received 3.6 ml of a local anesthetic to block conventional inferior alveolar nerve. In case of failure of the lock, were administered 3.6 ml of the same solution as in the periodontal ligament injection complement. The signal subjective lip anesthesia, the presence of pulpal anesthesia and no pain during pulpectomy were evaluated respectively by questioning the patient, via the stimulating device electrical pulp (pulp tester) and a verbal analogue scale. Statistical analysis was performed using the chi-square test, Kruskal Wallis and likelihood ratio. All patients reported lip anesthesia after blockade of the inferior alveolar nerve. The mepivacaine showed higher values (68.2%) for pulpal anesthesia after blockade of the inferior alveolar nerve and lidocaine (90%) after injection in the periodontal ligament. The mepivacaine showed higher values for analgesia (72.7%) after blocking the inferior alveolar nerve and lidocaine (90%) after injection in the periodontal ligament. After the failure of the blockade of the inferior alveolar nerve, the pain in the pulp chamber was the most frequent and after the failure of the periodontal ligament injection, pain in the channel. However, these differences were not statistically significant. Therefore, the three local anesthetic solutions behave similarly and did not exhibit effective pain management in treating irreversible pulpitis in mandibular molars.

The effect of intravenous dexmedetomidine on the duration of brachial plexus block

BACKGROUND: Dexmedemomidine, a highly selective alpha-2 adrenoreceptor agonist has an analgesic and sedative effect without causing respiratory depression. In this study, we compared the duration of brachial plexus block (BPB), the time at which the patient first feels pain after performing BPB, the need for use of analgesics, and the occurrence rate of complications while continuous infusion with dexmedetomidine was used for sedation in patients undergoing BPB, to a control group, who were only infused with normal saline. METHODS: BPB was performed in 48 patients scheduled for upper limb surgery. Infraclavicular approach was provided with 40 ml of 1.5% mepivacaine and 200 microg of epinephrine using nerve stimulator. After verification of successful block, dexmedetomidine group received dexmedetomidine (loading dose 0.1 microg/kg/min for the first 10 minutes followed by a maintenance dose of 0.005 microg/kg/min as required to maintain bispectral index 60-80). In the control group, normal saline was infused at a rate of 10 ml/hr. The duration of BPB, the time at which the patient first feels pain after performing BPB, frequency of complication, and the use of analgesics of the both groups were checked. RESULTS: The motor and sensory block duration, and the time at which the patient first feels pain after BPB were longer in the dexmedetomidine group compared to the control group. And the need for analgesics were less in the dexmedetomidine group. CONCLUSIONS: Intravenous administration of dexmedetomidine prolongs the duration of BPB.

A New Anterior Approach for Fluoroscopy-guided Suprascapular Nerve Block: A Preliminary Report

BACKGROUND: The aim of the study was to investigate the feasibility of fluoroscopy-guided anterior approach for suprascapular nerve block (SSNB). METHODS: Twenty patients with chronic shoulder pain were included in the study. All of the nerve blocks were performed with patients in a supine position. Fluoroscopy was tilted medially to obtain the best view of the scapular notch (medial angle) and caudally to put the base of coracoid process and scapular spine on same line (caudal angle). SSNB was performed by introducing a 100-mm, 21-gauge needle to the scapular notch with tunnel view technique. Following negative aspiration, 1.0 ml of contrast was injected to confirm the scapular notch, and 1 % mepivacaine 2 ml was slowly injected. The success of SSNB was assessed by numerical rating scale (NRS) before and after the block. RESULTS: The average NRS was decreased from 4.8 +/- 0.6 to 0.6 +/- 0.5 after the procedure (P < 0.05). The best view of the scapular notch was obtained in a medial angle of 15.1 +/- 2.2 (11-19degrees) and a caudal angle of 15.4 +/- 1.7degrees (12-18degrees). The average distance from the skin to the scapular notch was 5.8 +/- 0.6 cm. None of the complications such as pneumothorax, intravascular injection, and hematoma formation was found except one case of partial brachial plexus block. CONCLUSIONS: SSNB by fluoroscopy-guided anterior approach is a feasible technique. The advantage of using a fluoroscopy resulted in an effective block with a small dose of local anesthetics by an accurate placement of a tip of needle in the scapular notch while avoiding pneumothorax.

Transient Adverse Neurologic Effects of Spinal Pain Blocks

OBJECTIVE: Chronic neck or back pain can be managed with various procedures. Although these procedures are usually well-tolerated, a variety of side effects have been reported. In this study we reviewed cases of unexpected temporary adverse events after blocks and suggest possible causes. METHODS: We reviewed the records of patients treated with spinal pain blocks between December 2009 and January 2011. The types of blocks performed were medial branch blocks, interlaminar epidural blocks and transforaminal epidural blocks. During the first eight months of the study period (Group A), 2% mepivacaine HCL and triamcinolone was used, and during the last six months of the study period (Group B), mepivacaine was diluted to 1% with normal saline. RESULTS: There were 704 procedures in 613 patients. Ten patients had 12 transient neurologic events. Nine patients were in Group A and one was in Group B. Transient complications occurred in four patients after cervical block and in eight patients after lumbar block. Side effects of lumbar spine blocks were associated with the concentration of mepivacaine (p<0.05). The likely causes were a high concentration of mepivacaine in five patients, inadvertent vascular injection in three patients, intrathecal leak of local anesthetics in one, and underlying conversion disorder in one. CONCLUSION: Spinal pain blocks are a good option for relieving pain, but clinicians should always keep in mind the potential for development of inevitable complications. Careful history-taking, appropriate selection of the anesthetics, and using real-time fluoroscopy could help reduce the occurrence of adverse events.