Certified Nurses Operating Room (CNOR) Practice Exam

Which of the following is a colloid used in fluid resuscitation?

1. Normal saline

2. Dextran

3. Lactated Ringer's

4. 5% dextrose in water

The correct answer is: Dextran

Dextran is a colloidal solution used in fluid resuscitation because it contains large molecules that help to increase oncotic pressure in the blood vessels. This characteristic is beneficial during fluid resuscitation, as it aids in expanding the intravascular volume by drawing fluid into the vascular compartment from surrounding tissues. This can be particularly important in clinical scenarios such as hemorrhagic shock or severe dehydration, where maintaining blood pressure and perfusion to vital organs is critical. Colloids like Dextran play a distinct role compared to crystalloids, which are solutions with smaller molecules that primarily help in the hydration of the patient but may not provide the same volume expansion effect as colloids. The other options—normal saline, Lactated Ringer's, and 5% dextrose in water—are all classified as crystalloids because they contain electrolytes and/or glucose, but lack the large molecular structures essential for creating oncotic pressure. Therefore, Dextran stands out as a colloid option for effective fluid resuscitation in appropriate clinical contexts.