Asthma symptoms, asthma diagnosis, asthma treatmen

Heliox is a mixture of helium and oxygen, with not less than 20 % oxygen. Usual combination ratio is 70 parts helium to 30 parts oxygen or 80 parts helium to 20 parts oxygen.

Heliox has been used for more than 70 years in medical applications and is widely used in diving applications. Heliox as a breathable gas for medical treatment in pulmonary disease was first introduced in 1934 by Barach. Its use was seen in COPD and asthma treatment.

Helium is one of the lightest gas, and it replaces nitrogen present in air which is much heavier. Helium is an inert gas i.e. it does not react with other substances. As Heliox is three times lighter than air, is easier to breath and faces much less resistance in airways.

Heliox is administered in a similar fashion as any other breathing gas. Heliox can be given by high flow nasal cannula, hood or facemask. Room air should not enter heliox breathing system as that will dilute the gas and increase its density.

Heliox can be used for jet nebulization. As heliox is a lighter gas, high flow rates are needed to produce medically useful aerosol.

Uses of Heliox:
Beneficial effects have been observed in patients with:
asthma,chronic obstructive pulmonary disease (COPD),bronchiolitis,bronchopulmonary dysplasia and,upper airways obstruction.

Risks with Heliox system:

Hypothermia.
Infants who are administered Heliox via hood face risk of hypothermia. Heliox has high thermal conductivity and there is  consequent risk of hypothermia when the gas temperature is 36°C, especially when heliox is administered for long periods. The risk of hypothermia can be avoided with adequate warming and humidification of the heliox, using standard devices.

Hypoxia.
Faulty gas mixture containing less than 20 % oxygen is the cause for hypoxia. This risk is reduced by never administering 100% helium to a closed system, and always using heliox that contains at least 20% oxygen. Oxygen monitor in a breathing system should always be used.

Delivery of Too Much Volume.
If the mechanical ventilator delivers more than the set volume, there is a risk of volume-induced injury, pressure induced injury, or hypocarbia. This is of particular concern with ventilators not designed for heliox administration.

Improper nebulization.
Running a jet nebulizer with too low a flow of heliox can result in inadequate aerosol delivery to the patient at a time when aerosol delivery is critical.

category: Health    

Asthma is a chronic inflammatory disease of airways of the lungs. Asthma is often linked to heredity and environment.
Asthma is considered as a major public health problem in many countries. Asthma is one of the most common chronic disease affecting both adults and children.
According to World Health Organization an estimated 300 million people worldwide suffer from asthma, with 250,000 annual deaths attributed to the disease.
Asthma attack is characterized by sudden attacks of labored breathing, chest constriction and coughing.
Traditionally, asthma is considered to be a condition characterized by narrowing of airways where in the patients would gasp for breath.
Despite the availability increasing treatment, asthma-related morbidity and mortality continues to rise.
The prevalence of asthma is increasing in developed as well developing countries through the world. The current prevalence is estimated to be 5 to more than 10%.
In a normal individual, various airborne allergens (triggers) stimulate the production of antibodies and other chemicals in controlled quantity, which destroy the allergen but don’t harm the body.
But in allergic individual who have asthma there is over production of antibodies and other chemicals which cause inflammation of the airways, which is hallmark of asthma attack.

category: Health