Diabetic ketoacidosis (DKA) is an acute complication of diabetes mellitus and one of the common emergency cases in internal medicine. The pathophysiological changes in DKA are mainly metabolic acidosis, severe dehydration, imbalance of electrolyte and acid-base balance, malfunction of oxygen carrying system, peripheral circulatory failure and renal insufficiency, and central nervous system dysfunction. The pathophysiological changes in DKA are mainly metabolic acidosis, severe dehydration, electrolyte and acid-base balance disorders, malfunction of oxygen carrying system, peripheral circulatory failure and renal insufficiency, central nervous system dysfunction. Clinical manifestations: The patient’s original diabetic symptoms such as excessive drinking, thirst, polyuria and weakness are significantly aggravated, accompanied by anorexia, nausea, vomiting, irritability, headache, deep and fast breathing, and the smell of acetone (rotten apple smell) in the mouth. As the disease worsens, the patient becomes severely dehydrated, urinates little or no urine, the skin elasticity decreases, the blood pressure drops, and drowsiness, lethargy and even coma appear in the late stage. Clinical manifestations due to causative factors such as infection can be masked by DKA symptoms. Any patient with coma, acidosis, dehydration, shock should consider the possibility of DKA. 2. Laboratory tests: urine glucose and urine ketones are strongly positive. Blood glucose is mostly 16.7-33.3mmol/L or even higher, blood ketone body >4.8mmol/L, CO2 binding decreased, alkali residual negative value increased, blood PH <7.35, HCO3- decreased, blood potassium can be normal or high before treatment, hypokalemia can occur after treatment, blood BUN, CR high, plasma osmolality mildly increased, total leukocyte count even without combined The total white blood cell count may exceed 10×109/L even without co-infection. 3. Common complications: shock, serious infection, heart failure, cardiac arrhythmia, renal failure, cerebral edema, upper gastrointestinal bleeding, etc. Second, the treatment measures 1, rehydration: rehydration is an important key measure to save DKA. If there is no heart failure, it is appropriate to input 1000-2000ml within 2h, and later adjust the amount and speed of rehydration according to urine volume, blood pressure, peripheral circulation, central venous pressure, etc. The total amount of the first 24h can be 4000-6000ml, or even more. When the blood sugar drops to 13.9mmol/L, it can be changed to 5% glucose water plus insulin rehydration. 2, small dose insulin therapy: 0.1U/Kg/h, this method is simple, safe, effective, can avoid hypokalemia, hypoglycemia, cerebral edema. 3, correct electrolyte and acid-base balance disorders: actively monitor electrolyte levels, correct hypokalemia, alkaline supplementation should not be too early, too much, too fast, no obvious acidosis large respiratory, can be temporary without alkaline supplementation. 4. Treatment of predisposing diseases and complications: actively anti-infection and correction of possible complications. Nursing and rehabilitation points Daily oral and skin care, prevention of decubitus ulcers and secondary infections, close observation of changes in condition, such as mental status, respiration, blood pressure, heart rate, volume of intake and output, etc. Preventive points Prevent infection, avoid stress such as trauma, and use insulin treatment correctly and timely.