Pathophysiology
What happens to oxygen delivery when blood flow to a tissue is reduced?
Oxygen delivery decreases.
Which lab value increases when tissues are poorly perfused and cells rely on anaerobic metabolism?
Lactate.
Name two general physical manifestations of decreased tissue perfusion.
cool skin, pallor, delayed capillary refill, weak pulses, pain, numbness/tingling, or weakness.
What term describes inadequate blood flow to tissues and organs?
Hypoperfusion
A patient's blood pressure decreases significantly, and the nurse notices that the patient's urine output is also decreasing. What does this suggest?
Decreased renal perfusion.
When cells do not receive enough oxygen, what type of metabolism do they rely on?
Anaerobic metabolism.
Which cardiac biomarker is commonly used to identify myocardial injury?
Troponin.
A patient has an ischemic extremity. Would you expect the extremity to be warm or cool?
cool
What term describes inadequate blood supply that causes tissue to receive insufficient oxygen to meet its metabolic demands?
Ischemia
A patient has a cool, pale foot with a weak pedal pulse. What should the nurse recognize?
The patient has decreased peripheral perfusion and possible ischemia.
What happens to ATP production when cells switch from aerobic to anaerobic metabolism?
ATP production decreases
Which diagnostic test can show ST-segment changes and T-wave abnormalities associated with myocardial ischemia?
EKG/ECG
A patient suddenly develops facial drooping, difficulty speaking, and weakness on one side of the body. What type of ischemia should the nurse suspect?
Cerebral ischemia.
What is the term for irreversible cell injury and death caused by prolonged lack of blood flow?
Infarction
A patient suddenly develops chest pressure while resting. The pain is unpredictable and does not consistently improve with rest. Which condition should the nurse suspect?
Unstable angina
During prolonged ischemia, decreased ATP causes the sodium-potassium pump to malfunction. What happens to the cell?
Sodium and water enter the cell, causing the cell to swell.
A patient is suspected of having an arterial blockage in the leg. Which diagnostic test would allow the healthcare team to visualize blood flow through the vessels?
Doppler ultrasound
A patient develops sudden severe leg pain, pallor, an absent pedal pulse, numbness, and weakness. What do these findings suggest?
Acute limb ischemia.
What is the term for restoring blood flow to tissue after a period of ischemia?
Reperfusion
A patient suddenly develops a cold, pale leg with an absent pedal pulse and numbness. What should the nurse do?
Notify the healthcare provider immediately.
Put these events in the correct order: cellular dysfunction, decreased blood flow, decreased ATP, anaerobic metabolism, cellular hypoxia, cell death.
decreased blood flow, cellular hypoxia, anaerobic metabolism, decreased ATP, cellular dysfunction, cell death.
What is the normal range for Hgb and Hct?
12-16 g/dL; 37-47%
A patient experiencing myocardial ischemia reports chest pressure, shortness of breath, diaphoresis, and nausea. Why are these findings concerning?
They indicate possible myocardial ischemia and could represent an acute coronary syndrome.
What term describes additional cellular damage that can occur when blood flow and oxygen return to previously ischemic tissue?
Reperfusion injury
A patient has prolonged hypotension and is showing signs of poor perfusion. The nurse notes confusion, cool skin, weak pulses, decreased urine output, and an elevated lactate. What is the nurse's greatest concern?
The patient is experiencing significant tissue hypoperfusion with cellular ischemia and is at risk for irreversible organ injury.