Lactated Ringers (LR)

Indications

Clinical Efficacy
- Single-Center, Multiple-Crossover SALT-ED Trial of Balanced Crystalloids vs Normal Saline in Non-Critically Ill Adults in the Emergency Department (NEJM, 2018) [MEDLINE]: n = 13,347
  - Among noncritically ill adults treated with intravenous fluids in the emergency department, there was no difference in hospital-free days between treatment with balanced crystalloids and treatment with saline

Clinical Efficacy
- Single-Center, Multiple-Crossover SALT-ED Trial of Balanced Crystalloids vs Normal Saline in Non-Critically Ill Adults in the Emergency Department (NEJM, 2018) [MEDLINE]: n = 13,347
  - Among noncritically ill adults treated with intravenous fluids in the emergency department, there was no difference in hospital-free days between treatment with balanced crystalloids and treatment with saline

Clinical Efficacy
- Cluster-Randomized, Multiple-Crossover SMART-MED and SMART-SURG Trial of Balanced Crystalloids vs Normal Saline in Critically Ill Adults (NEJM, 2018) [MEDLINE]: n = 7942 (5 ICU’s)
  - Balanced Crystalloids (Lactated Ringers or Plasma-Lyte) for Intravenous Fluid Resuscitation Decreased the Composite Outcome of All-Cause Mortality Rate, Need for New Renal Replacement Therapy, and Persistent Renal Dysfunction, as Compared to Normal Saline

Liver Disease (see End-Stage Liver Disease, [[End-Stage Liver Disease]]): impaired hepatic metabolism will impair lactate conversion
Metabolic Alkalosis (see Metabolic Alkalosis, [[Metabolic Alkalosis]]): lactated ringers may worsen pre-existing metabolic alkalosis

1831 (Europe): first clinical use of crystalloids during the India Blue Cholera pandemic
1896 (Holland): Hartog Hamburger (Dutch physiologist) invented “normal saline”: he intended to use this fluid in the in vitro study of erythrocyte lysis
1880 (England): Sydney Ringer invented “Ringer’s solution”: he used this fluid to sustain contractility in isolated frog hearts
- The fluid was inadvertently made with tap water (instead of distilled water) and the inadvertent presence of calcium likely led to the experiment being successful
- Ringer analyzed the fluid and found that it contained calcium, sodium, potassium, chloride, and magnesium
1930’s (USA): pediatrician Alexis Hartmann added lactate to a solution very similar to Ringer’s solution, creating a forerunner of “Lactated Ringer’s” (see Lactated Ringers, [[Lactated Ringers]]): lactate was added by Hartmann to “buffer” the solution (creating a “balanced” solution)

Balanced Crystalloids: mildly hypotonic lactate or acetate buffered solutions (with signficantly lower chloride concentrations than saline)
- Lactated Ringer’s (LR)
- Acetate Ringer’s
- Hartmann Solution
- Isolyte (from Braun)
- Plasma-Lyte (from Baxter Healthcare)
Unbalanced Crystalloids : contain no buffer (note: additionally, normal saline has higher chloride concentration than the above)
- Normal Saline (NS) (see Normal Saline, [[Normal Saline]]): 0.9% NaCl
- Half Normal Saline (see Half Normal Saline, [[Half Normal Saline]]): 0.45% NaCl
- Quarter Normal Saline (see Quarter Normal Saline, [[Quarter Normal Saline]]): 0.22% NaCl
- Dextrose 5% in Water (D5W) (see Dextrose 5% in Water, [[Dextrose 5% in Water]]): Dextrose 5%
- D5 Normal Saline (D5NS): Dextrose 5% + 0.9% NaCl
- D5 Half Normal Saline (D5 1/2NS): Dextrose 5% + 0.45% NaCl
- D5 Quarter Normal Saline (D5 1/4NS): Dextrose 5% + 0.22% NaCl
Comparative Data
- Use of balanced crystalloid is associated with decreased kidney pathology in rat model of hemorrhagic shock, as compared to unbalanced crystalloid [MEDLINE]
- Chloride-restrictive IV fluid resuscitation strategy is associated with decreased renal injury [MEDLINE]: may be related to hyperchloremia’s induction of renal vasoconstriction

“Balanced” Crystalloid Solution: isotonic with blood
- Contains 130 mEq of Sodium per liter (130 mmol/L)
- Contains 109 mEq of Chloride per liter (109 mmol/L)
- Contains 28 mEq of Lactate per liter (28 mmol/L)
  - Lactate is normally converted to pyruvate by lactate dehydrogenase in the liver (via the Cori cycle) -> pyruvate (the first designated substrate of the gluconeogenesis pathway) is subsequently converted to glucose, a process which generates bicarbonate
- Contains 4 mEq of Potassium per liter (4 mmol/L)
- Contains 3 mEq of Calcium per liter (1.5 mmol/L)
Similar in composition to Hartmann’s solution (which is more commonly found in British and Irish hospitals)

IVF Resuscitation: 20 to 30 ml/kg body weight/hr
- Lactated Ringers is generally considered unsuitable for maintenance fluid therapy, as the sodium content is too low (especially for children)

Congestive Heart Failure/Fluid Overload (see Congestive Heart Failure, [[Congestive Heart Failure]])

Hypercalcemia (see Hypercalcemia, [[Hypercalcemia]])
Hyperkalemia (see Hyperkalemia, [[Hyperkalemia]]): usually only occurs in the setting of renal failure and high-volume lactated ringers infusion (due to the relatively small amount of potassium per liter)
Hyperlactatemia (see Lactic Acidosis, [[Lactic Acidosis]]): incremental increase in serum lactate is usually small in the absence of an abnormality in lactate clearance (Crit Care Med, 1997) [MEDLINE]
Hyponatremia (see Hyponatremia, [[Hyponatremia]])
Metabolic Alkalosis (see Metabolic Alkalosis, [[Metabolic Alkalosis]]): due to hepatic conversion of lactate to bicarbonate

Effect of intravenous lactated Ringer’s solution infusion on the circulating lactate concentration: Part 3. Results of a prospective, randomized, double-blind, placebo-controlled trial. Crit Care Med 1997;25:1851-4 [MEDLINE]
Rapid saline infusion produces hyperchloremic acidosis in patients undergoing gynecologic surgery. Anesthesiology. 1999 May;90(5):1265-70 [MEDLINE]
Association between a chloride-liberal vs chloride-restrictive intravenous fluid administration strategy and kidney injury in critically ill adults. JAMA. 2012 Oct 17;308(15):1566-72. doi: 10.1001/jama.2012.13356 [MEDLINE]
Balanced vs unbalanced crystalloid resuscitation in a near-fatal model of hemorrhagic shock and the effects on renal oxygenation, oxidative stress, and inflammation. Resuscitation. 2012 Jun;83(6):767-73. doi: 10.1016/j.resuscitation.2011.11.022. Epub 2011 Dec 4 [MEDLINE]
The ideal crystalloid – what is ‘balanced’? Curr Opin Crit Care. 2013 Aug;19(4):299-307. doi: 10.1097/MCC.0b013e3283632d46 [MEDLINE]
Crystalloids for Fluid Resuscitation in Sepsis: Where Is the Balance? Ann Intern Med. 2014 Jul 22. doi: 10.7326/M14-1565 [MEDLINE]
Balanced Crystalloids versus Saline in Noncritically Ill Adults. N Engl J Med. 2018 Mar 1;378(9):819-828. doi: 10.1056/NEJMoa1711586 [MEDLINE]
Balanced Crystalloids versus Saline in Critically Ill Adults. N Engl J Med. 2018 Mar 1;378(9):829-839. doi: 10.1056/NEJMoa1711584 [MEDLINE]