From the Research
I recommend initiating isotonic fluid resuscitation with normal saline at 150-200 mL/hour for this patient who shows signs of hypernatremia, azotemia, and moderate renal impairment. The elevated sodium (156 mEq/L), high BUN/Cr ratio (31.3), and elevated BUN (47 mg/dL) suggest significant dehydration with pre-renal azotemia, as discussed in the context of fluid and electrolyte imbalances 1. Begin with a 1-2 L bolus of normal saline over 2-4 hours, then transition to a maintenance rate.
Key Considerations
- Monitor fluid status closely to avoid fluid overload given the reduced GFR of 49.2 mL/min.
- Repeat labs in 6 hours to assess sodium correction and kidney function, aiming for sodium correction of no more than 8-10 mEq/L in 24 hours to prevent cerebral edema.
- The elevated anion gap (18) suggests a mild metabolic acidosis that should improve with volume repletion.
- Once the sodium begins to normalize, consider switching to half-normal saline to continue gentle correction.
- Assess for and address the underlying cause of dehydration, which may include limited oral intake, excessive losses, or medication effects, as outlined in the principles of fluid therapy 1.
- Careful monitoring of urine output and daily weights will help guide ongoing fluid management, emphasizing the importance of maintaining fluid balance in patient care 2.