Ace the Certified Nephrology Nurse 2025 Exam – Dive into Dialysis Mastery!

The most commonly used type of fluid replacement in patients with acute kidney injury (AKI) is isotonic crystalloid solutions. These solutions, which include normal saline or lactated Ringer's solution, are preferred as they help maintain a stable intravascular volume and ensure adequate renal perfusion. When a patient experiences AKI, timely and effective fluid resuscitation is critical to avert further kidney damage, and isotonic crystalloids are effective in restoring hemodynamic stability without causing significant shifts in osmotic balance.

The use of hypotonic solutions would not be appropriate in patients with AKI because these can lead to hyponatremia and may worsen fluid overload, potentially exacerbating renal injury. Colloidal solutions are less commonly used in AKI management due to concerns about their effect on renal blood flow and the potential for allergic reactions. Oral rehydration solutions may not provide adequate volume resuscitation in cases of severe AKI requiring intravenous therapy, thus making them less suitable in acute settings. Therefore, isotonic crystalloid solutions are the standard choice for fluid replacement in these patients.