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

To evaluate the hemodynamic changes following SMOFlipid emulsion therapy with after bupivacaine intoxication in swines.

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.

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.

The SMOFlipid emulsion is a option for reversing hypotension in cases of intoxication by bupivacaine.