Bone marrow suppression during chemotherapy can lead to a drop in white blood cells, which can manifest as weakness, muscle aches, loss of appetite, drowsiness, and low fever. White blood cells help the body fight against foreign bacteria. When white blood cells are too low, the resistance will become weak and easily catch a cold or other infectious diseases. Therefore, during the cold season, patients should go to public places less often, pay attention to keeping warm when going out, and wear masks and scarves. Reduce visits from friends and relatives, and avoid contact with infected people who have colds and other diseases. Due to the cold weather, the blood vessels in the arms will contract when they are cold, which will easily cause difficulties in needle insertion or drug extravasation. Therefore, for patients who do not have a central venous line (PICC or PORT), rub your hands or use a hand-warming bag before infusion. During infusion, be sure to protect the infusion arm, reduce arm movement, and promptly inform the nurse or physician of any pain or discomfort in the punctured arm. In addition, patients during chemotherapy should pay attention to personal hygiene, such as washing hands frequently, especially before and after meals or after contact with others. Wash your hands carefully for at least 15 seconds, taking care to clean all the skin on your hands, the backs of your fingers, the tips of your fingers and the crevices of your fingers. Even in cold weather, keep the indoor air ventilated and at the right temperature regularly. Choose a diet that is high in protein, calories and vitamins that is easy to digest and absorb. When fever appears and the body temperature exceeds 38.5 degrees, you must seek medical attention promptly and not take antibacterial and antipyretic drugs on your own. When the white blood cell count is <1×10 of 9 times/L, it is prone to serious infection and the doctor must be contacted immediately and protective isolation measures need to be applied.