Preoperative NPO guidelines specify which of the following fasting times for clear liquids, breast milk, and a light meal?

• A. Clear liquids up to 6 hours; breast milk up to 4 hours; a light meal up to 2 hours.
• B. Clear liquids up to 2 hours; breast milk up to 4 hours; a light meal up to 6 hours.
• C. Clear liquids up to 1 hour; breast milk up to 2 hours; a light meal up to 4 hours.
• D. Clear liquids up to 4 hours; breast milk up to 3 hours; a light meal up to 6 hours.

Answer: (B)

Minimizing the risk of aspiration during anesthesia is the main idea behind preoperative NPO timing. Clear liquids exit the stomach quickly, so a 2-hour window is considered safe. Breast milk contains more solids and fat and empties more slowly, but 4 hours is still enough for most patients to reduce gastric content. A light meal has solids and some fat, which delays emptying, so a 6-hour window is recommended to lower aspiration risk. These timings align with standard guidelines for healthy adults; alternative options either shorten the window too much or mismatch the typical gastric emptying times.