Which agent is most useful for raising the gastric pH just before induction of general anesthesia for an emergency cesarean section?

Which agent is most useful for raising the gastric pH just before induction of general anesthesia for an emergency cesarean section?

• A. Cimetidine
• B. Metoclopramide
• C. Ranitidine
• D. Sodium citrate

Answer: (D)

Reducing the acidity of gastric contents right before anesthesia helps lessen the injury if aspiration occurs. In an emergency cesarean, you need something that acts very quickly. Sodium citrate is an alkali buffer that rapidly neutralizes gastric acid, raising the pH within minutes. That immediate pH increase makes any aspirate less caustic to the lungs, which is crucial in a high-risk situation. The other options work differently. Cimetidine and ranitidine are H2 blockers; they lower acid production but take longer to have an effect and don’t immediately neutralize existing acid. Metoclopramide helps with gastric emptying, reducing stomach volume, but it doesn’t raise the pH. So the fastest, most reliable way to raise gastric pH just before induction in this emergency setting is sodium citrate.

Reducing the acidity of gastric contents right before anesthesia helps lessen the injury if aspiration occurs. In an emergency cesarean, you need something that acts very quickly. Sodium citrate is an alkali buffer that rapidly neutralizes gastric acid, raising the pH within minutes. That immediate pH increase makes any aspirate less caustic to the lungs, which is crucial in a high-risk situation.

The other options work differently. Cimetidine and ranitidine are H2 blockers; they lower acid production but take longer to have an effect and don’t immediately neutralize existing acid. Metoclopramide helps with gastric emptying, reducing stomach volume, but it doesn’t raise the pH. So the fastest, most reliable way to raise gastric pH just before induction in this emergency setting is sodium citrate.