First aid measures for hydrogen sulfide poisoning

Hydrogen sulfide is a chemical raw material with a wide range of uses in industry and medicine. In industry, it can make high-purity sulfur and identify metal ions. In medicine, the combination of hydrogen sulfide and hot springs has a good effect on the treatment of skin diseases.

But hydrogen sulfide gas is a pungent and harmful gas. Lower concentrations can irritate the respiratory tract and cause people to cough, while higher concentrations can cause death. What are the first aid measures for hydrogen sulfide poisoning?

Hydrogen sulfide is a colorless gas that is irritating and asphyxiating. Low concentration exposure only causes local irritation to the respiratory tract and eyes. At high concentrations, systemic effects are more obvious, manifested as central nervous system symptoms and suffocation symptoms. Hydrogen sulfide has a "rotten egg-like" odor, but extremely high concentrations quickly cause olfactory fatigue and the odor is no longer noticeable.

First aid measures

1. On-site rescue is extremely important

Because the air contains extremely high concentrations of hydrogen sulfide, it often causes multiple deaths from electric shock at the scene. Timely rescue can reduce the mortality rate. The patient should be immediately removed from the scene to fresh air. Provide oxygen immediately if conditions permit.

2. Maintain vital signs

Cardiopulmonary-cerebral resuscitation should be performed immediately on patients with respiratory or cardiac arrest. If artificial respiration can be performed promptly on those who suffer respiratory arrest at the scene of the accident, subsequent cardiac arrest can be avoided. When performing mouth-to-mouth artificial respiration, the practitioner should avoid inhaling the patient's exhaled air or hydrogen sulfide escaping from the patient's clothes to avoid secondary poisoning.

3. Symptomatic and supportive treatment is the main treatment

Hyperbaric oxygen therapy plays an important role in accelerating the recovery of coma and preventing and treating cerebral hydrops. All comatose patients, regardless of whether they have been resuscitated or not, should be given hyperbaric oxygen therapy as soon as possible, but this must be combined with comprehensive treatment. Patients with obvious symptoms of poisoning should be given adrenal glucocorticoids early, in sufficient amounts and for a short period of time, which is beneficial for preventing and treating cerebral edema, pulmonary edema and myocardial damage. If there are symptoms of eye irritation, rinse immediately with clean water and treat symptomatically.

4. There is no consensus on the indications and methods for the use of methemoglobin-forming agents.

Theoretically, methemoglobin-forming agents are suitable for treating intracellular asphyxiation caused by hydrogen sulfide, but are ineffective against the reflex respiratory inhibition of the nervous system. Appropriate use of isopentyl nitrite, sodium nitrite or 4-dimethylaminophenol (4-DMAP) can oxidize hemoglobin in the blood into methemoglobin, which can combine with free sulfhydryl groups to form sulfhydryl hemoglobin and detoxify; it can also seize the sulfhydryl groups bound to cytochrome oxidase, restore the enzyme to improve hypoxia.

Precautions

1. Respiratory protection

When the concentration in the air exceeds the standard, wear a transitional gas mask (half mask). During emergency rescue or evacuation, it is recommended to wear an oxygen respirator or an air respirator.

2. Eye protection

Wear chemical safety glasses.

3. Body protection

Wear anti-static work clothes.

4. Hand protection

Wear chemical-resistant gloves.

5. Others

Smoking, eating and drinking are strictly prohibited at the work site. After work, take a shower and change clothes. Change and wash work clothes in time. Operators should learn to save themselves and each other. When entering a tank, confined space or other high-concentration area, supervision is required.