When should Ringer's (lactated Ringer's solution) lactate not be used?

Contraindications for Ringer's Lactate

Ringer's lactate should be avoided in patients with severe traumatic brain injury (TBI) or head trauma, and in patients with rhabdomyolysis or crush syndrome. 1

Primary Contraindication: Severe Head Trauma/TBI

The most critical contraindication is severe head trauma or traumatic brain injury. 1, 2

• Ringer's lactate has an osmolarity of 273-277 mOsm/L, making it hypotonic compared to plasma (275-295 mOsm/L) when measured by real osmolality rather than theoretical osmolality 1, 2
• This hypotonic nature causes fluid shift into damaged cerebral tissue, potentially worsening cerebral edema 1, 2
• A secondary analysis from the PROMMTT study demonstrated that Ringer's lactate was associated with higher adjusted mortality compared with normal saline in trauma patients 1
• For brain-injured patients, 0.9% saline (osmolarity 308 mOsm/L) is the recommended isotonic crystalloid of choice 2

Rhabdomyolysis and Crush Syndrome

Avoid Ringer's lactate in suspected or proven rhabdomyolysis or crush syndrome. 2, 3

• Potassium levels may increase markedly following reperfusion of crushed tissue, even with intact renal function 2, 3
• Ringer's lactate contains 4 mmol/L of potassium, which poses additional risk in these patients 1, 2
• Use 0.9% normal saline instead, as it contains no potassium and provides the aggressive volume expansion needed to prevent acute kidney injury from myoglobin precipitation 3
• Target urine output of 200-300 mL/hour is needed to flush myoglobin through the kidneys 3

Common Pitfalls and Caveats

The Hyperkalemia Concern is Largely Unfounded in Most Patients

• Despite containing 4 mmol/L potassium, large randomized studies involving 30,000 patients showed comparable plasma potassium concentrations between balanced fluids and 0.9% saline 1, 2
• In renal transplant recipients (high-risk population), patients receiving 0.9% saline actually developed higher potassium levels than those receiving Ringer's lactate 1, 2
• Recent research in patients with eGFR <30 mL/min/1.73m² found no independent association between Ringer's lactate use and development of hyperkalemia 4
• The presence of potassium in Ringer's lactate (4 mmol/L) should NOT be considered a contraindication in patients with mild-to-moderate hyperkalemia or renal dysfunction, except in the specific scenarios of rhabdomyolysis/crush syndrome 1, 2, 4

Lactate Content Does Not Significantly Elevate Serum Lactate

• While Ringer's lactate contains 27.6 mmol/L of lactate, research shows only a modest mean increase of 0.93 mmol/L in serum lactate after a 30 mL/kg bolus in healthy volunteers 5
• This increase is not clinically significant and should not interfere with lactate monitoring in sepsis or shock 5
• The lactate in Ringer's solution is metabolized at nearly the same rate as endogenous lactate 6

When Ringer's Lactate IS Appropriate

• Ringer's lactate is preferred over normal saline in most other clinical scenarios, including general trauma resuscitation (without severe TBI), diabetic ketoacidosis, and general fluid resuscitation 1, 7
• In diabetic ketoacidosis, Ringer's lactate was associated with faster resolution of high anion gap metabolic acidosis compared to normal saline 7
• Balanced crystalloids like Ringer's lactate avoid the hyperchloremic metabolic acidosis associated with large volumes of 0.9% saline 1, 2