Internists use normal saline.
Surgeons use lactated ringers.
Its a cultural difference, perpetuated by dogma.
Here’s how Burton Rose characterized Ringer’s solution in his classic Clinical Physiology of Acid-Base and Electrolyte disorders:
During the control phase, physicians were able to prescribe IV fluids per personal preference. During the experimental period, chloride rich solutions were restricted to specific clinical conditions: hyponatremia, traumatic brain injury and cerebral edema. Otherwise patients were given low chloride solutions: Hartman’s solution, plasma-Lye 148 and 4% albumin.
The primary outcome was the change in creatinine and incidence of AKI, using RIFLE criteria. Secondary outcomes included need for acute dialysis, length of of ICU and hospital stay and survival.
The study consisted of 1644 admissions to the ICU, 760 in the control period and 773 in the experimental period. The two cohorts were well matched with significant differences only with metabolic diagnosis being more common in the control period (7 vs 4.4%) and neurologic disorders being more common in the experimental period (6.2 vs 8.8%).
The difference in the fluids being used was dramatic and this resulted in significant differences in electrolyte exposure: