Hemodynamic changes in lipid emulsion therapy (SMOFlipid) for bupivacaine toxicity in swines

Abstract

PURPOSE:To evaluate the hemodynamic changes following SMOFlipid emulsion therapy with after bupivacaine intoxication in swines. METHODS: Large White pigs were anesthetized with thiopental, tracheal intubation was performed and mechanical ventilation was 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 two groups and received 4 ml.kg -1 of saline solution or 4 ml.kg -1 of SMOFlipid emulsion 20%. 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. SMOFlipid emulsion therapy was able to improve blood pressure mainly by increasing vascular resistance since the cardiac index had no significant improvement in our study. Hemodynamic results of the use of lipid emulsion in bupivacaine intoxication were better than the control group. CONCLUSION: The SMOFlipid emulsion is a option for reversing hypotension in cases of intoxication by bupivacaine. Key words: Anesthesia, Local. Bupivacaine. Lipids. Hemodynamics. Fat Emulsions, Intravenous. Swine. RESUMO OBJETIVO:Avaliar as alterações hemodinâmicas da terapia lipídica com SMOFlipid após intoxicação com bupivacaína em suínos. MÉTODOS: Suínos da raça Large White foram anestesiados com tiopental, realizada intubação traqueal e mantidos em ventilação mecânica. As variáveis hemodinâmicas foram registradas através de pressão invasiva e cateterização da artéria pulmonar (cateter de Swan-Ganz). Após período de 30 minutos de repouso, 5 mg.kg -1 de bupivacaína foram injetados por via endovenosa e novas medidas hemodinâmicas foram realizadas 1 minuto após; os animais foram então aleatoriamente divididos em dois grupos e receberam 4 ml.kg -1 de solução salina ou 4 ml.kg -1 da emulsão tipo SMOFlipid a 20%. As alterações hemodinâmicas foram reavaliadas aos 5, 10, 15, 20 e 30 minutos. RESULTADOS: A intoxicação pela bupivacaína causou queda da pressão arterial, índice cardíaco e do trabalho sistólico dos ventrículos principalmente sem importantes alterações das resistências vasculares. A terapia com a emulsão SMOFlipid foi capaz de melhorar a pressão arterial através, principalmente, do aumento das resistências vasculares uma vez que o índice cardíaco não apresentou melhora expressiva em nosso estudo. Os resultados hemodinâmicos com o uso da emulsão lipídica na intoxicação pela bupivacaína foram melhores que no grupo controle. CONCLUSÃO: A emulsão SMOFlipid é uma opção para reverter a hipotensão em caso de intoxicação pela bupivacaína.

Electrophysiological, haemodynamic, and mitochondrial alterations induced by levobupivacaine during myocardial ischemia in a pig model: protection by lipid emulsions?

“…It would be helpful to investigate the effects of levobupivacaine and Intralipid ® using a study design similar to ours in other animal species. Indeed, the present investigation is globally in agreement with some studies , but differs with some others . Indeed, Bedocs et al.…”

“…The myocardial contractility was significantly improved a few minutes after the administration of Intralipid â . The efficacy of lipid emulsions has also been reported in the treatment of poisoning by LA in pigs [41,42]. The pig seems to be an appropriate model for the study of electrophysiological and haemodynamic parameters in myocardial ischemia [15].…”

Hemodynamic changes with high infusion rates of lipid emulsion. Experimental study in swine

“…Figure 7 shows that bolus injection of lipid solution had no repercussions on SVRI in T 1. However, after starting lipid pump infusion, and after T 20 , all values were higher than at T 0 and T 1 , in addition toT 10 <T 20 until T 50 (p=0.0001). No differences between infusion rates were noticed.…”

“…The intravenous infusion rate can be increased up to 100 mg/kg/min, which is much higher than the dose employed for parenteral nutrition 8,9 . In lipid treatment for local anesthetic toxicity, hemodynamic studies with various types of solutions have mainly demonstrated an increase in vascular resistance, especially pulmonary resistance 10,11 . However, the hemodynamic impact of high rates of lipid emulsion infusions, as recommended by medical societies, without previous knowledge of drug-related toxicity has still not been fully elucidated.…”

Does the use of fish oil-based lipid emulsion in the clinical setting of total parenteral nutrition and lipid rescue therapy interfere with common laboratory analytes on Roche Cobas 6000?

“…While traditionally soybean lipid emulsion is used as a rescue therapy for calcium channel blockers, beta-blockers, tricyclic antidepressants overdose and local anaesthetic systemic toxicity, 20 , 21 fish oil-based lipid emulsion has been used as well. 22 , 23…”