Which crystalloid solution is MOST appropriate as a maintenance fluid in a patient who has undergone a 3-hour open abdominal surgery and remains intubated in the ICU with normal renal function and no electrolyte abnormalities?

• A 0.9% Normal saline
• B 5% Dextrose
• C 0.45% NaCl with 5% Dextrose
• D Ringer's lactate (Hartmann's solution) ✓

Explanation

Balanced crystalloid solutions such as Ringer's lactate (Hartmann's) are the preferred maintenance fluids in the perioperative period because their electrolyte composition approximates plasma, reducing the risk of hyperchloraemic metabolic acidosis seen with large volumes of 0.9% normal saline. 5% Dextrose alone provides no electrolytes and causes hyponatraemia if used for resuscitation. 0.45% NaCl-dextrose is hypotonic and can precipitate cerebral oedema in at-risk patients. Large volumes of normal saline cause dilutional hyperchloraemic acidosis, impairing renal blood flow.

Reference: Morgan & Mikhail's Clinical Anesthesiology, 6th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.