The care of critically ill patients is a systematic and difficult nursing process, which is mainly noted in the following five aspects: 1. attention should be paid to the care of the patient’s eye, mouth and nose skin; 2. attention should be paid to the supplementation of nutrition and water; 3. the function of the patient’s excretion should be maintained; 4. the fluency of various catheters of the patient should be maintained; 5. the function of the limbs should also be maintained. The eye, mouth and nose secretions of critically ill patients should be wiped with wet cotton balls or gauze in a timely manner. Those whose eyelids cannot close on their own are prone to corneal drying, leading to conjunctivitis or complications such as corneal ulcers. You can apply antibiotic eye ointment and cover with petroleum jelly gauze for protection; you should also take good care of the mouth; pay attention to keeping the mattress and underwear neat and comfortable to prevent bedsores; you should also try to increase the patient’s appetite and help patients with self-care defects to eat. For those who cannot eat, nasal feeding or parenteral nutrition should be given; for patients who do not have enough fluids, sufficient water should be supplemented, and the second stool should be kept unobstructed; those with urinary retention and incontinence should take appropriate measures, such as indwelling catheterization if necessary, and those with constipation can be given laxative drugs or enemas as appropriate; those with fecal incontinence should keep the bed mattress neat and clean and do a good job of skin care. Many kinds of catheters are often placed in critically ill patients, such as infusion tubes, blood vessels, oxygen tubes, urinary catheters, postoperative drainage tubes, etc. They should be properly fixed and safely placed to prevent the catheter from twisting and blocking and falling off under pressure to ensure smooth flow. We also need to maintain the functional position of the patient’s joints, and assist the patient to do passive limb activities and massage when the condition permits to promote blood circulation, increase muscle strength, prevent muscle atrophy and venous thrombosis, and maintain the function of the limbs. Finally, the patient’s rights should be respected, the patient’s self-esteem should be protected, the patient should be encouraged, comforted and guided in a timely manner, the purpose of various resuscitation measures should be explained, and psychological care should be provided to relieve the patient’s psychological stress.