ACCS Hemodynamic Monitoring and Shock Management 1 — Questions and Answers
Question 1: What is the target mean arterial pressure (MAP) recommended for critically ill adults to ensure adequate organ perfusion?
- 40–50 mmHg
- 65–100 mmHg (Correct answer)
- 110–130 mmHg
- 20–40 mmHg
Correct answer: 65–100 mmHg
A MAP of 65–100 mmHg is the accepted target range in critically ill patients, with 65 mmHg as the minimum threshold recommended in septic shock guidelines.
Question 2: Which hemodynamic parameter best reflects left ventricular preload in a critically ill patient?
- Central venous pressure (CVP)
- Pulmonary artery wedge pressure (PAWP) (Correct answer)
- Systemic vascular resistance (SVR)
- Cardiac output (CO)
Correct answer: Pulmonary artery wedge pressure (PAWP)
PAWP (pulmonary capillary wedge pressure) reflects left ventricular end-diastolic pressure and is the most reliable indirect measure of left ventricular preload.
Question 3: A patient in cardiogenic shock would most likely present with which hemodynamic profile?
- Elevated CO and decreased SVR
- Decreased CO and elevated SVR (Correct answer)
- Normal CO and normal SVR
- Elevated CO and elevated SVR
Correct answer: Decreased CO and elevated SVR
Cardiogenic shock is characterized by pump failure causing decreased cardiac output, with the body compensating through vasoconstriction to maintain blood pressure.
Question 4: Which type of shock is classically characterized by distributive physiology with markedly low systemic vascular resistance?
- Cardiogenic shock
- Hypovolemic shock
- Obstructive shock
- Septic shock (Correct answer)
Correct answer: Septic shock
Septic shock is the prototypical distributive shock, where inflammatory mediators cause widespread vasodilation resulting in low SVR and maldistribution of blood flow.
Question 5: The Fick equation is primarily used to calculate which hemodynamic parameter?
- Mean arterial pressure
- Cardiac output (Correct answer)
- Pulmonary vascular resistance
- Stroke volume variation
Correct answer: Cardiac output
The Fick equation calculates cardiac output by dividing oxygen consumption (VO2) by the arteriovenous oxygen content difference (CaO2 – CvO2).
Question 6: What is the normal cardiac index (CI) range for adult patients?
- 0.5–1.0 L/min/m²
- 4.5–6.5 L/min/m²
- 2.2–4.0 L/min/m² (Correct answer)
- 1.0–2.0 L/min/m²
Correct answer: 2.2–4.0 L/min/m²
Normal cardiac index, which is cardiac output indexed to body surface area, is 2.2–4.0 L/min/m²; values below 2.2 suggest a low cardiac output state.
Question 7: Which waveform characteristic indicates proper pulmonary artery catheter wedge position?
- Large a and v waves with x and y descents
- Loss of pulsatile waveform with a low, flat pressure tracing (Correct answer)
- Elevated diastolic pressure equal to systolic pressure
- Bifid waveform with prominent respiratory variation
Correct answer: Loss of pulsatile waveform with a low, flat pressure tracing
A wedged catheter position produces a non-pulsatile, low-pressure tracing reflecting left atrial pressure, because the inflated balloon isolates the tip from pulmonary artery pulsations.
ACCS Hemodynamic Monitoring and Shock Management 1
What is the target mean arterial pressure (MAP) recommended for critically ill adults to ensure adequate organ perfusion?