The manifestations of gas poisoning are as follows: 1. Mild poisoning: Its symptoms include headache, dizziness, panic, nausea, vomiting and other symptoms. Early symptoms of gas poisoning are headache, dizziness, palpitations, nausea, vomiting, weakness of the limbs, and even a brief coma. At this time, the poisoned person is generally still clear, in the inhalation of fresh air or get rid of the poisoned environment, the symptoms quickly disappeared, and generally do not leave sequelae; 2, medium-heavy poisoning: in addition to the aggravation of the early symptoms, but also accompanied by flushed face, lips cherry red, sweating, restlessness. At this time, the patient is delirious, but after a period of time after rescue, the patient can gradually wake up; 3, severe poisoning: the patient is delirious, call out, urinary and fecal incontinence, cold limbs, dilated pupils, blood pressure drops, breathing is weak or stops, limbs are stiff or paralyzed, and electrocardiogram suggests myocardial damage or cardiac arrhythmia.