Effect of hypertonic saline on electrocardiography QRS duration in rabbit model of bupivacaine toxicity resuscitated by intravenous lipid.

Intravenous lipid emulsion is established therapy for bupivacaine induced cardiotoxicity. The benefit of combined hypertonic saline and lipid treatment is unexplored. In this experiment, sedated rabbits were resuscitated from bupivacaine-induced asystole with intravenous lipid according to the Association of Anaesthetists of Great Britain and Ireland's guideline, or by identical lipid dosing with hypertonic saline: 6 mEq x kg(-1) 21% sodium chloride. Early electrocardiography QRS prolongation was less with lipid plus hypertonic saline (mean (SD) QRS 0.19 (0.07) s lipid only vs 0.09 (0.01) s lipid plus hypertonic saline; p = 0.003) at 9 min though not different from the lipid only group at 20 min. No difference was observed in rates of circulatory return (7/10 lipid only and 9/10 lipid plus hypertonic saline; p = 0.58) or survival (5/10 lipid only and 6/10 lipid plus hypertonic saline; p = 1.00). Some benefit to cardiac conduction may be afforded by hypertonic saline co-administered with lipid emulsion in bupivacaine-induced cardiotoxicity.