The reason you can't drink water before surgery is to prevent pulmonary aspiration, which occurs when stomach contents, including water, enter the lungs during anesthesia. This can block the airways or cause lung infections like pneumonia, potentially leading to severe complications or death. Anesthesia relaxes muscles, including those that control the stomach opening, increasing the risk that stomach contents move up the esophagus while lying flat during surgery. Having an empty stomach significantly reduces this risk. However, current guidelines are evolving. Clear fluids such as water are now often allowed up to two hours before surgery because they typically leave the stomach quickly and do not pose a significant risk. The traditional fasting rule of no food or drink for 8 to 12 hours before surgery is more cautious to prevent complications, especially in vulnerable patients like the elderly or those with medical conditions. But drinking a small amount of water a couple of hours before surgery is increasingly seen as safe and beneficial for hydration and comfort right before surgery. In summary:
- Drinking water is generally restricted before surgery to prevent fluid in the stomach from entering the lungs during anesthesia (pulmonary aspiration).
- This risk is serious because stomach fluids are acidic and damaging to lung tissue.
- Clear liquids often can be consumed up to two hours before surgery under current medical guidelines.
- Patients should always follow their specific doctor's instructions, which might still require longer fasting times depending on the case.
These points reflect current understanding and evolving guidelines on preoperative fasting and hydration.
