Understanding the properties of gases, liquids and the various laws regarding them, is important for respiratory therapists, since, those concepts will be merged into their practice. By knowing these concepts, respiratory therapists will have a wide range of knowledge, which will allow them to optimize patient care.

Hyperbaric oxygen therapy depends on the concept of treating various conditions by exposing the patient to pressures above the atmospheric pressure. Different situations such as carbon monoxide poisoning, decompression sickness, smoke inhalation, skin grafts and air embolism could be treated by hyperbaric oxygen therapy.

One of the concepts that hyperbaric oxygen therapy depends on is Boyle’s law. Boyle’s law states that there is an inverse relationship between the pressure exerted by a gas and its volume if the temperature is constant. Due to the high level of pressure in the hyperbaric oxygen therapy there will be a decrease in the volume of the air emboli. This is considered as one of the clinical applications of Boyle’s Law.

Alveolar and arterial partial pressure of oxygen will be increased during hyperbaric therapy. The increase in the alveolar partial pressure of oxygen will be due to Dalton’s law that explains the relationship between the partial pressure of the gas and the total pressure. Additionally, the increased partial pressure of oxygen in the alveoli results in an increase in the amount of oxygen dissolved in the blood, which is a clinical application of Henry’s law.

Work of breathing could be affected during hyperbaric oxygen therapy. Since increasing the pressure results in increasing the density of gas, correspondingly, increasing the density of the gas, will increase the work of breathing. Additionally, temperature should be continuously monitored inside the hyperbaric chamber considering Charles law that the temperature will increase with increase of the pressure.

Some patients could require mechanical ventilation during hyperbaric therapy. Respiratory therapists should closely monitor the patient-ventilator system since the increased density of the gas may significantly increase the resistance, thereby reducing the flow delivered by the ventilator.

Respiratory therapists do not need to memorize all the gas laws, but they need to understand them, since they play a prominent role in different devices and concepts used by respiratory therapists.

Reference:

1-Egan’s Fundamentals of Respiratory Care book

2-Mosby’s Respiratory care Equipment book