Oxygen, Perfusion, and Ventilation Basics
This process refers to the movement of air in and out of the lungs.
What is ventilation?
The earliest observable sign of hypoxemia is often this change in behavior.
What is restlessness or anxiety?
The respiratory center that controls breathing rhythm is located in this part of the brain.
What is the medulla in the brainstem?
A patient with COPD is receiving oxygen via nasal cannula at 4 L/min. He becomes drowsy and his respirations drop to 8 per minute.
What complication of oxygen therapy is occurring, and what should the nurse do first?
What is oxygen-induced hypoventilation, and the nurse should reduce the oxygen flow rate, stimulate the patient to breathe, and closely monitor oxygen saturation.
A patient with pneumonia has an SpO₂ of 89% on room air and crackles in the lower lobes.
Which diagnostic test directly measures arterial oxygen levels, and why is it used instead of pulse oximetry?
What is arterial blood gas (ABG) analysis, because it measures PaO₂, PaCO₂, and pH, giving more precise information about gas exchange and acid–base balance than pulse oximetry.
This term describes the exchange of gases (O₂ and CO₂) between the alveoli and the blood.
What is respiration?
Late signs of hypoxia include this bluish discoloration of the skin and mucous membranes.
What is cyanosis?
Chemoreceptors respond primarily to changes in the level of this gas in the blood.
What is carbon dioxide (CO₂)?
patient on 6 L/min nasal cannula complains of dry nose and throat irritation.
Explain why humidification is essential and what physiologic issue it prevents.
What is humidification to maintain mucosal moisture and prevent airway irritation, thickened secretions, and impaired gas exchange?
You note that your patient’s pulse oximeter reading dropped from 98% to 84%, but the patient looks comfortable with normal respirations.
List two possible non-clinical reasons for this finding before assuming hypoxia
What are cold fingers, motion artifact, or sensor displacement (equipment interference, not true desaturation)?
This process describes the movement of oxygenated blood through the body’s tissues.
What is perfusion?
List three vital sign changes that may indicate hypoxemia.
What are increased pulse rate, elevated blood pressure, and increased respiratory rate?
In patients with chronic lung disease, the respiratory drive is triggered by decreased levels of this gas.
What is oxygen (hypoxic drive)?
A nurse applies a simple face mask to a patient and notes the oxygen reservoir bag completely deflates during inspiration.
What is wrong, and how does this affect oxygenation?
What is insufficient oxygen flow rate, causing the patient to rebreathe exhaled CO₂, resulting in increased carbon dioxide retention and reduced oxygenation?
A patient recovering from abdominal surgery refuses to use the incentive spirometer because of incisional pain.
What explanation can the nurse give to emphasize the importance of its use, and what alternative intervention could support oxygenation?
The nurse explains that deep breathing prevents alveolar collapse and hypoxemia, and may splint the incision or encourage pursed-lip breathing to reduce pain while maintaining ventilation.
A patient is restless, dyspneic, and has a pulse oximetry reading of 86%. These are clinical manifestations of this condition.
What is hypoxemia?
Hypoxia affects cognition and consciousness because of inadequate oxygen delivery to this organ.
What is the brain?
Explain the role of alveoli in oxygenation.
They are the site of gas exchange, where oxygen diffuses into blood and CO₂ diffuses out.
You are preparing to administer nebulized medication to a patient with wheezing. The patient reports dizziness and tremors after the first treatment.
Explain the nursing priority and possible cause.
What is pause the treatment and notify the provider, since systemic absorption of bronchodilator can cause sympathetic nervous system side effects?
While performing chest physiotherapy on a patient with thick secretions, the nurse observes increased heart rate and dizziness.
What is the likely cause, and what immediate nursing action should be taken?
What is excessive vagal stimulation or hypoxemia during percussion, and the nurse should stop therapy, reassess oxygen saturation, and administer supplemental oxygen if needed?
The respiratory center of the brain is located in this part of the central nervous system.
What is the medulla oblongata?
Explain why a patient with hypoxia may appear drowsy and confused.
Because decreased oxygen to brain cells impairs neurologic function and consciousness.
Blood returning from the lungs to the left atrium carries this type of blood.
What is oxygenated blood?
During oxygen therapy, a patient suddenly develops substernal chest pain, cough, and dyspnea. You suspect oxygen toxicity.
Explain the underlying mechanism and the appropriate nursing intervention.
What is prolonged exposure to high oxygen concentration causing alveolar capillary membrane damage and decreased surfactant production, and the nurse should reduce FiO₂, monitor lung sounds, and notify the provider?
During tracheostomy care, the patient suddenly coughs, and the tracheostomy tube dislodges onto the bed.
Explain the immediate nursing priority and the rationale.
What is maintain the airway by inserting a new sterile tracheostomy tube or using a manual resuscitation bag over the stoma, because loss of the artificial airway can lead to hypoxia within minutes?