Critical Care | 2019
Mechanism of arrhythmias during the infusion of Ringer’s acetate and Ringer’s lactate solutions during cardiac surgery: new insights
Abstract
We have read with great interest the article by Pfortmueller et al. about fluid management in patients undergoing cardiac surgery [1]. This randomized double blind study showed equivalence between Ringer’s lactate solution and Ringer’s acetate solution in terms of hemodynamic stability, as well as the acid-base and ionic profiles of the two patient populations. However, they observed a higher prevalence of postoperative cardiac arrhythmia in the group receiving Ringer’s lactate solution without a change in the pH or electrolyte values. Previous work has shown that acetate-based dialysate solutions cause hemodynamic and rhythmic disruption. Acetate induces the production of cyclic adenosine monophosphate (cAMP) and cytokines that increase the synthesis of nitric oxide (NO). Studies have shown that acetate-induced NO production induces hypotension during dialysis. Noris et al. showed that the levels of NO and interleukin (IL)-1β are higher after dialysis with acetate than after dialysis with bicarbonate. They suggested that acetate-activated monocytes produce Il-1β that in turn stimulates endothelial cells to produce NO, which can result in hemodynamic instability and arrhythmias [2]. Regarding acid-base balance, it has been shown that Ringer’s lactate solution has a strong ion difference (SID) of 28 while acetate-based solutions have a SID of around 36. Infusion of Ringer’s lactate solution results in a larger reduction in pH when compared to acetate solutions. In vivo, regardless of whether a lactateor acetatebased solution is infused, serum potassium levels do not change to a degree that could result in rhythm disturbances [3].