What is the appropriate use of D5 (Dextrose 5%) Lactated Ringer's (LR) solution for hydration and electrolyte replenishment?

D5 Lactated Ringer's Solution: Clinical Use and Appropriate Applications

Primary Indication

D5 Lactated Ringer's (D5LR) solution has limited routine clinical utility and should generally be avoided in favor of either dextrose-free crystalloids or separate administration of dextrose and electrolytes based on specific patient needs. 1

Specific Clinical Scenarios Where D5LR May Be Appropriate

Diabetic Ketoacidosis (DKA) - Transition Phase Only

• Once serum glucose reaches 250 mg/dL during DKA treatment, switch from saline-based fluids to 5% dextrose with 0.45-0.75% NaCl plus potassium (20-40 mEq/L as 2/3 KCl and 1/3 KPO4 in pediatrics; 20-30 mEq/L in adults). 1

• This prevents hypoglycemia while continuing insulin therapy to resolve ketoacidosis. 1

• The dextrose concentration must be maintained to allow continued insulin administration at therapeutic rates without inducing dangerous hypoglycemia. 1

Nephrogenic Diabetes Insipidus (NDI) - Emergency Hypernatremic Dehydration

• For hypernatremic dehydration in NDI patients, use 5% dextrose solutions (not D5LR specifically) as the primary rehydration fluid because salt-containing solutions worsen hypernatremia. 1

• Salt-containing solutions like lactated Ringer's have tonicity (300 mOsm/kg H2O) that exceeds typical NDI urine osmolality (100 mOsm/kg H2O) by 3-fold, requiring approximately 3 liters of urine to excrete the osmotic load from 1 liter of isotonic fluid. 1

• Calculate initial fluid administration rate based on physiological maintenance requirements (children: 100 mL/kg/24h for first 10 kg, 50 mL/kg/24h for 10-20 kg, 20 mL/kg/24h for remaining weight; adults: 25-30 mL/kg/24h). 1

Clinical Scenarios Where D5LR Should NOT Be Used

Anaphylaxis and Severe Allergic Reactions

• Use normal saline, not lactated Ringer's or dextrose-containing solutions, for fluid resuscitation in anaphylaxis. 1

• Lactated Ringer's may contribute to metabolic acidosis, and dextrose rapidly extravasates from intravascular to interstitial space, making it ineffective for volume expansion. 1

• Administer 1-2 L normal saline to adults at 5-10 mL/kg in first 5 minutes; children require up to 30 mL/kg in first hour. 1

Acute Gastroenteritis and Infectious Diarrhea

• Isotonic crystalloids (lactated Ringer's or normal saline without dextrose) should be used for severe dehydration requiring IV therapy. 1, 2

• Oral rehydration solution (ORS) remains first-line for mild-moderate dehydration. 1, 2, 3

• Switch to IV fluids only with severe dehydration, shock, altered mental status, or ORS failure. 1, 2

Head Trauma and Neurological Injury

• Avoid dextrose-containing solutions in head trauma as they increase mortality and worsen neurological outcomes without preventing brain edema. 4

• Lactated Ringer's solution (without dextrose) can be safely administered in large volumes (0.25 mL/g) without affecting blood electrolytes, neurological severity scores, or brain edema formation. 4

• Even small volumes of 5% dextrose (0.08-0.16 mL/g) significantly increased mortality rates and caused severe hyperglycemia (up to 1568 g%) and hyponatremia (as low as 92 mEq/L). 4

Routine Perioperative Fluid Replacement

• Initiation of IV fluid replacement with dextrose-containing solutions is unnecessary to prevent hypoglycemia in elective surgery and causes significant hyperglycemia. 5

• Even 500 mL of 5% dextrose in 0.9% saline caused plasma glucose elevation to 11.1 mmol/L (200 mg/dL) in 72% of non-diabetic patients 15 minutes post-infusion. 5

• Patients receiving lactated Ringer's or normal saline without dextrose remained normoglycemic throughout despite average fasting times of 13 hours. 5

Key Clinical Pitfalls

Lactate Monitoring Concerns

• Lactated Ringer's infusion at resuscitation rates (1 L over 1 hour) does not falsely elevate circulating lactate concentrations in hemodynamically stable patients. 6

• Do not disregard elevated lactate values in patients receiving rapid lactated Ringer's infusion—they represent true hyperlactatemia requiring investigation. 6

• However, inadequately cleared lactated Ringer's from IV catheters can falsely elevate lactate in blood samples drawn from the same catheter. 6

Hyperglycemia Risk

• Dextrose-containing solutions cause clinically significant hyperglycemia even in non-diabetic patients, which may worsen outcomes in critical illness. 5

• The transient hyperglycemia from D5-containing fluids persists for at least 1 hour, with 33% of patients maintaining glucose ≥8 mmol/L (144 mg/dL) at 1 hour post-infusion. 5

Pediatric Considerations

• In pediatric perioperative settings, Ringer-lactate with 0.9-1% dextrose (not 5%) may be appropriate to balance hypoglycemia prevention with hyperglycemia avoidance. 7

• The lower dextrose concentration (0.9-1% vs 5%) provides adequate glucose supplementation without excessive hyperglycemia risk in children. 7