Hemodynamic changes with two lipid emulsions for treatment of bupivacaine toxicity in swines

Abstract

PURPOSE:To compare the hemodynamic changes following two different lipid emulsion therapies after bupivacaine intoxication in swines. METHODS:Large White pigs were anesthetized with thiopental, tracheal intubation performed and mechanical ventilation instituted.Hemodynamic variables were recorded with invasive pressure monitoring and pulmonary artery catheterization (Swan-Ganz catheter).After a 30-minute resting period, 5 mg.kg -1 of bupivacaine by intravenous injection was administered and new hemodynamic measures were performed 1 minute later; the animals were than randomly divided into three groups and received 4 ml.kg -1 of one of the two different lipid emulsion with standard long-chaim triglyceride, or mixture of long and medium-chain triglyceride, or saline solution.Hemodynamic changes were then re-evaluated at 5, 10, 15, 20 and 30 minutes. RESULTS:Bupivacaine intoxication caused fall in arterial blood pressure, cardiac index, ventricular systolic work index mainly and no important changes in vascular resistances. Both emulsion improved arterial blood pressure mainly increasing vascular resistance since the cardiac index had no significant improvement. On the systemic circulation the hemodynamic results were similar with both lipid emulsions. CONCLUSION:Both lipid emulsions were efficient and similar options to reverse hypotension in cases of bupivacaine toxicity.

The effects of intravenous lipid emulsion on hemodynamic recovery and myocardial cell mitochondrial function after bupivacaine toxicity in anesthetized pigs

“…We based our 4 mL/kg lipid emulsion dose on previously published rat 11 and pig models, 17 in which lipid emulsion was shown to increase MAP after bupivacaine intoxication. This dose of lipid emulsion was shown to increase MAP also without bupivacaine toxicity in our pilot study.…”

“…We deliberately chose to use a larger dose of lipid emulsion than that recommended in guidelines of regional anesthesia societies, 3 since in animal experiments on local anesthetic toxicity, larger lipid doses have been required for a rescue effect. 11,17…”

Parenteral emulsions and liposomes to treat drug overdose

“…parameters, but PK values were not measured [39]. was significantly less in blood serum over saline due to haloperidol's 474 strong binding to blood proteins [42], this study was the first demon-475 stration of pH gradient liposomal particles for detoxification therapy.…”