Oxygen Therapy Indications, Hazards, & Contraindications
What are the 3 ways to assess for the need of oxygen therapy?
-Laboratory measures -Clinical problem or condition -Manifestations
What are the five hazards associated with oxygen therapy?
-Oxygen Toxicity -Depression of Ventilation -Retinopathy of Prematurity -Absorption Atelectasis -Fire Hazard
What are the manifestations associated with hypoxemia?
-Tachypnea -Tachycardia -Cyanosis -Distressed overall appearance
How is O2 therapy used?
-correct acute hypoxemia -decrease the symptoms of chronic hypoxemia -decrease cardiopulmonary workload
Toxicity of oxygen is caused by what?
Free radicals
Breathing high levels of O2 quickly depletes the body's what levels?
Nitrogen
What are the two factors that determine the harmful effects of oxygen therapy?
PO2 and exposure time
This is an abnormal eye condition that occurs in some premature or low birth weight infants who receive supplemental O2
ROP (Retinopathy of Prematurity)
Chronic hypoxemia can lead to what?
Right ventricular failure (cor pulmonale)
For an alert patient complete collapse of the lung is not an issue due to what mechanism that periodically inflates the lung?
Sigh
O2 therapy corrects hypoxemia by?
increasing alveolar and blood levels of O2
What is the goal of oxygen therapy?
maintain adequate tissue oxygenation while minimizing cardiopulmonary work
What are the two laboratory measures to measure hypoxemia?
Hemoglobin saturation and partial pressure of oxygen
Why is the exposure to 100% O2 for more than 24 hours should be avoided whenever possible?
High FiO2 is acceptable if the concentration can be decreased to 0.70 (70%) within 2 days and to 0.50 (50%) or less in 5 days
What are the indications of administering O2 therapy in the care of adults, children, and infants older than 28 days?
O2 therapy is indicated if PaO2 is less than 60 mm Hg or SaO2 is less than 90%
How can the need for supplemental O2 be assessed?
-laboratory measures -clinical history or status -bedside patient evaluation
An FiO2 greater than what poses a significant risk for absorption atelectasis?
50%
The partial pressure of oxygen needs to be below?
60 mm Hg breathing room air
To minimize the risk of ROP, keep the PaO2 in an infant to less than what?
80 mm Hg
The hemoglobin saturation needs to be below?
90% breathing room air
What defends against O2 free radicals?
Antioxidants
Why is prevention of hypoxia always the first priority?
Concern that O2 therapy can cause hypoventilation should never preclude administration of O2 to a patient in need.
Giving supplemental oxygen to COPDers will suppress their what?
Hypoxic drive
How does the cardiopulmonary system compensate for hypoxemia?
Increasing ventilation and cardiac output