What is the ideal crystalloid for resuscitation fluid?

There is an emerging debate about normal saline inducing metabolic acidosis and increasing the risk for renal injury, with a resulting shift toward the use of ringers lactate. The latter, however, in large volumes, may be associated with hyponatremia and its consequences. Ringers acetate is posited as the ideal “balanced crystalloid” in terms of both acid-base status and tonicity. Recent review here. High level trials are needed.