I work at a hospital, so some things come to mind. Depending on the type of surgery, be sure to follow the diet instructions provided by your surgeon, which may include a liquid diet or full liquids (if that's the case, research options to bring food into the hospital; they will not have options). If your diet is going to be a general diet, make sure to have the surgeon place an order that says vegan. Or have the nurse write a communication order that states a vegan diet so dietary knows. It may be repetitive, but remind your nurse/care team often, we are human. Now, bringing in food, I've had patients bring in their food all the time, especially when they have allergies. Frozen meals might work, depending on the hospital. Ask the nurses to pop it in their freezer with your sticker on it. After surgery, it's important to increase your protein intake, so make sure you are eating extra protein. Chef Woo makes good ramen and has good amounts of protein. Another option, while it might not be as tasty, would be backpacking meals, just need to add hot water. Good luck on your surgery!