The physiological requirement of patients with portal hypertension is reduced because of abnormal water metabolism, so the principle of surgical rehydration cannot be copied, otherwise the patient will get sicker and sicker with the infusion. The formula for surgical rehydration is: daily rehydration amount = physiological requirement + daily loss + half of the accumulated loss. After we make up the accumulated loss, the daily rehydration amount is equal to the physiological requirement plus the daily loss. We often encounter patients who are referred to outside hospitals with large amounts of rehydration fluid, forming large amounts of ascites and getting sicker. In fact, due to portal hypertension, the patient’s physiological requirements should be reduced. But how much reduction is appropriate for calculation? For example, if a patient with portal hypertension has a drainage tube after surgery and loses about 1000 ml of ascites per day and 2000 ml of urine per day due to the use of diuretics, if the formula is followed, the daily rehydration volume is equal to 2000 ml of physiological needs plus 1000 ml of ascites loss plus 2000 ml of urine loss for a total of 5000 ml of fluid. If the surgeon mechanically follows the formula to replenish 5000 ml of fluid per day, the patient will soon have massive ascites, electrolyte disturbance, low potassium, low sodium and low protein anemia, and then start the hepatic and renal syndrome, which is likely to die. So be sure to control the total amount of fluid infusion and do not apply it rigidly. I strongly recommend that my colleagues in the hepatobiliary surgery group revise the specialized rehydration formula specifically for patients with poor liver function. My personal experience, in the absence of a suitable formula to use, the method of controlling the total amount of fluid, that is, the total amount of rehydration fluid per day should not exceed 3500 ml in general, within 3000-3500 ml is appropriate, even if the patient’s daily loss of ascites plus urine exceeds 3000 ml, so that the patient’s water metabolism is in negative equilibrium, that is, the amount of water replenished is not as much as that lost. As long as the vital signs are stable, do not increase the amount of rehydration. It is also important to maintain electrolyte balance. Potassium supplementation is 5-6 grams per day, calcium supplementation is 20 ml of calcium gluconate per day, and saline is at least 1000 ml to maintain electrolyte stability. There are also some details that need to be adjusted according to the condition. In a word, do not copy the formula, many classical contents of surgery need to be revised due to medical practice.