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.

Amnesia and Pain Relief after Cardiopulmonary Resuscitation in a Cancer Pain Patient: A Case Report

The mechanism of chronic pain is very complicated. Memory, pain, and opioid dependence appear to share common mechanism, including synaptic plasticity, and anatomical structures. A 48-yr-old woman with severe pain caused by bone metastasis of breast cancer received epidural block. After local anesthetics were injected, she had a seizure and then went into cardiac arrest. Following cardiopulmonary resuscitation, her cardiac rhythm returned to normal, but her memory had disappeared. Also, her excruciating pain and opioid dependence had disappeared. This complication, although uncommon, gives us a lot to think about a role of memory for chronic pain and opioid dependence.

Glucose levels and hemodynamic changes in patients submitted to routine dental treatment with and without local anesthesia

OBJECTIVE: The aim of this study was to (1) observe the extent to which hemodynamic and glucose measurements change in patients submitted to a dental procedure with and without a local anesthetic and a vasoconstrictor (LAVA; 2 percent mepivacaine with adrenaline 1100,000) and (2) correlate those parameters with the patients' anxiety levels. METHOD: This was an unblinded, random, prospective, and observational study with paired groups. Patients were evaluated during two different consultations during which they either did or did not receive a local anesthetic/vasoconstrictor. RESULTS: Thirty-seven patients ranging in age from 18 to 45 years (mean 30.4 ± 5.5 years) were evaluated. Hemodynamic parameters, including systolic blood pressure, diastolic blood pressure, heart rate, and glucose levels, did not change significantly in healthy patients, regardless of whether a LAVA was administered during the dental treatment. CONCLUSION: The patients' anxiety statuses neither varied significantly nor showed any correlation with the studied hemodynamic parameters and glucose levels, regardless of whether local anesthetics were used.

Coma profundo consecutivo a bloqueo del plexo braquial: a propósito de 1 caso / Deep coma after block of the brachial plexus: apropos of 1 case

Se presenta el caso clínico infrecuente de un paciente masculino de 17 años de edad, que sufrió un accidente de tránsito y por el cual mostraba herida avulsiva del miembro superior izquierdo. Se le practicó bloqueo del plexo braquial por la técnica perivascular interescalénica, donde se utilizó como agente anestésico la mepivacaína al 2 porciento. Minutos después, el paciente cae en coma profundo con resolución muscular total, pupilas midriáticas y arreactivas, reflejo fotomotor, corneal y parpabral ausentes. Se intuba y acopla al respirador mecánico Mark-8, y la hemodinamia se mantuvo sin presentar convulsiones. Posteriormente, de forma paulatina, se recupera totalmente sin dejar secuelas

Efeitos cardivasculares provocados pela administraçäo do cloridrato de mepivacaína 2 (por cento) associado ao cloridrato de levonordefrina a 1:20.000, através das vias infiltrativa intrabucal e endovenosa: estudo comparativo em cäes / Cardiovascular effects caused by the administration of 2 (percent) mepivacaine hidrocloride associated to 1:20.000 levonordefrin hidrocloride, through the intraoral infiltrative and endovenous ways: comparative study in dogs

Avaliamos os efeitos do cloridrato de mepivacaína 2 (por cento) (0,514mg/kg de peso) associado ao cloridrato de levonordefrina a 1:20.000 (1,28mg/kg de peso) - CARBOCAINE, sobre as pressöes arteriais sistólica, diastólica e média e a freqüencia cardíaca de cäes anestesiados, após a administraçäo infiltrativa intrabucal e endovenosa. Nossos resultados indicaram que o cloridrato de mepivacaína 2 (por cento) (0,514mg/kg de peso) associado ao cloridrato de levonordefrina a 1:20.000 (1,28mg/Kg) näo determinou alteraçöes estatisticamente significativas na dinâmica vascular (pressöes arteriais sistólica, diastólica e média e a freqüencia cardíaca) quando a administraçäo foi realizada através da via infiltrativa intrabucal. A administraçäo endovenosa determinou aumentos estatisticamente significantes nas pressöes arteriais sistólica, diastólica e média e queda signicante na freqüencia cardíaca. As alteraçöes ocorridas foram observadas logo após o início da administraçäo da soluçäo anestésica, com retorno aos níveis normais, mantendo-se assim até o final do experimento