Gas Exchange Basics
What is gas exchange?
Transport of O2 to cells and removal of CO2 from cells.
What is a common breathing pattern seen in impaired gas exchange?
Use of accessory muscles.
What causes noisy respirations at EOL?
Define dyspnea.
A subjective feeling of breathing discomfort or shortness of breath.
What is cognition?
Processes related to knowledge and understanding (e.g., memory, language, attention).
What is impaired ventilation?
What is orthopnea?
Difficulty breathing when lying flat.
What is one intervention for noisy respirations?
Repositioning, scopolamine, glycopyrrolate, elevating HOB.
What triggers dyspnea physiologically?
Chemoreceptor response to low PaO2 or high PaCO2/acidosis.
Name one condition that causes cognitive impairment through hypoxia.
COPD or HF.
What is impaired transport?
Reduced oxygen-carrying capacity (e.g. anemia, low Hgb).
What does restlessness or agitation often indicate?
Early hypoxia.
What breathing pattern may appear in the dying process?
Cheyne-Stokes or ataxic breathing.
What is dyspnea crisis?
Sudden, severe worsening of dyspnea requiring rapid intervention.
What causes cognitive decline in Alzheimer's disease?
Abnormal proteins, plaques, and impaired neurotransmission.
Name a condition that impairs perfusion and gas exchange.
HF (pulmonary edema), blood loss, or poor cardiac output.
What does cyanosis of nail beds or skin indicate?
What medication is most effective for EOL dyspnea?
Opioids.
What should a nurse do first in a dyspnea crisis?
Stay with the patient and remain calm.
What is terminal delirium?
Confusion, agitation, and visions that occur in up to 88% of dying patients.
What ABG features indicate impaired gas exchange?
Hypoxemia or hypercapnia.
Why must nurses ask patients if they feel short of breath?
Because dyspnea is subjective.
Why is oxygen therapy reserved for hypoxemia at EOL?
It may not relieve dyspnea unless O2 is genuinely low; focus is comfort.
Name two pharmacological interventions for dyspnea.
Opioids and benzodiazepines (plus antibiotics, diuretics, bronchodilators when indicated).
What is one key intervention for families of patients experiencing terminal delirium?
Clear information, reassurance, and guidance on responding to their loved one.