Heliox is a mixture of Helium and oxygen being considered for use in asthma patients. Therapeutic strategies for patients with pulmonary medicine often employ bronchodilators or corticosteroids to reduce airway resistance and improve airflow.
As an alternative strategy, viscosity and density of the atmosphere manipulated to the same desired effect. Air consists of 21% oxygen, with most of the remaining oxide.
Oxygen and nitrogen almost equal densities, and thus change the rate of FiO2 (fraction of inspired oxygen) did not significantly alter the physical properties of the gas mixture. It can be replaced with less dense helium nitrogen dramatic reduction in the total density of air. This in turn reduces airway resistance, even without anatomical changes in the airways.
There are no evidence-based guidelines directing the use of Heliox. However, since it no significant side effects may have therapeutic trials in patients with obstructive upper airway conditions and respiratory compromise.
A low density gas mixture has the greatest positive impact on large airways with turbulent density-dependent flow, resulting in improved alveolar emptying and reduced pressure plateau. Given this, patients with severe asthma (mechanical ventilation) are ideal candidates for treatment Heliox.
Indeed, in the tests of intubated patients with status asthmaticus treated with Heliox showed decreased airway pressure, decreased PaCO2 (partial pressure of carbon dioxide, arterial), and improved acidosis. Patients with other serious diseases, such as postextubation upper airway obstruction or chronic obstructive pulmonary disease may also benefit.
Heliox therapy is recommended to start early respiratory muscle fatigue. Commonly used mixtures have helium-to-oxygen ratio of 80:20, 70:30, 60:40. Clinically, the best strategy is to use higher levels of it maintain an oxygen saturation 90%.
Using increasing concentrations of the mixture is done to maximize the advantage of linear low density gas breathing. However, sufficient oxygen is necessary to maintain alveolar oxygenation. The beneficial effect of Heliox therapy is often seen within a few minutes. More importantly, the fans and the instrumentation must be calibrated for use of Heliox.