手術麻醉前到底要空腹多久？

There is NO recommendation for ROUTINE use of:

• Gastrointestinal stimulants (metoclopramide)
• Gastric acid secretion blockers (H2 blockers)
• Antacids (bicarb, Na citrate)
• Antiemetics (droperidol, ondansetron)
• Anticholinergics (atropine, glycopyrrolate)
• Combinations of the above
  

Hint:

• These recommendations apply to healthy patients who are undergoing elective procedures. They are not intended for women in labor. Following the guidelines does not guarantee a complete gastric emptying has occurred.
• The fasting periods noted above apply to all ages.
• Examples of clear liquids include water, fruit juices without pulp, carbonated beverages, clear tea, and black coffee.
• Since non-human milk is similar to solids in gastric emptying time, the amount ingested must be considered when determining an appropriate fasting period.
• A light meal typically consists of toast and clear liquids. Meals that include fried or fatty foods or meat may prolong gastric emptying time. Both the amount and type of foods ingested must be considered when determining an appropriate fasting period.