CCRN - Review Hemodynamic Monitoring Questions and Answers 1 — Questions and Answers
Question 1: A patient in the ICU develops hypotension, tachycardia, and a decreased cardiac output. The pulmonary artery catheter reveals the following readings: CVP 1 mmHg, PAWP 4 mmHg, and SVR 1800 dynes/sec/cm-5. Which of the following conditions is the MOST likely cause of this hemodynamic profile?
- Cardiogenic shock
- Septic shock
- Hypovolemic shock (Correct answer)
- Anaphylactic shock
Correct answer: Hypovolemic shock
The hemodynamic profile of low CVP (preload), low PAWP (left ventricular preload), and high SVR (afterload) with a low cardiac output is characteristic of hypovolemic shock. The body compensates for the loss of volume by constricting blood vessels, which increases SVR, in an attempt to maintain blood pressure.
Question 2: A critical care nurse is performing a square wave test on an arterial line. The resulting waveform shows a rapid upstroke and downstroke, followed by two oscillations before returning to the arterial waveform. This finding indicates:
- An overdamped system
- An underdamped system
- A properly functioning system (Correct answer)
- Catheter whip artifact
Correct answer: A properly functioning system
A properly functioning arterial line system will produce 1-2 oscillations after the fast-flush square wave test. This indicates that the system is appropriately damped and providing accurate pressure readings. More than two oscillations would suggest an underdamped system, while fewer than 1.5 would indicate an overdamped system.
Question 3: A patient is admitted with decompensated right-sided heart failure. Which set of hemodynamic parameters would the nurse most expect to find?
- High CVP, high SVR, low PAWP
- Low CVP, low CO, high SVR
- High CVP, low PAWP, normal to high PVR (Correct answer)
- Low CVP, high PAWP, low SVR
Correct answer: High CVP, low PAWP, normal to high PVR
In right-sided heart failure, the right ventricle fails to pump effectively, leading to a backup of blood in the systemic venous circulation. This results in an elevated Central Venous Pressure (CVP). The Pulmonary Artery Wedge Pressure (PAWP), which reflects left-sided preload, would be low or normal unless there is concurrent left-sided failure. Pulmonary Vascular Resistance (PVR) may be elevated, as it is a common cause of right heart failure.
Question 4: The dicrotic notch on an arterial pressure waveform represents:
- The peak systolic pressure
- The opening of the aortic valve
- The closure of the aortic valve (Correct answer)
- The end of diastole
Correct answer: The closure of the aortic valve
The dicrotic notch is a small, downward deflection on the arterial waveform that follows the systolic peak. It signifies the closure of the aortic valve and the beginning of diastole. This closure causes a brief retrograde flow of blood, which creates the notch.
Question 5: A patient with septic shock has a low Systemic Vascular Resistance (SVR). Which of the following medications would be most appropriate to administer to address this specific hemodynamic alteration?
- Dobutamine
- Nitroglycerin
- Furosemide
- Norepinephrine (Correct answer)
Correct answer: Norepinephrine
Septic shock is a type of distributive shock characterized by massive vasodilation, leading to a decreased SVR. Norepinephrine is a potent vasopressor that causes peripheral vasoconstriction, thereby increasing SVR and helping to restore blood pressure. Dobutamine is an inotrope, Nitroglycerin is a vasodilator, and Furosemide is a diuretic.
Question 6: When leveling an arterial line transducer to obtain an accurate reading, the nurse should place it at the phlebostatic axis. This anatomical landmark is located at the intersection of:
- The second intercostal space and the mid-axillary line
- The fourth intercostal space and the mid-clavicular line
- The fifth intercostal space and the anterior axillary line
- The fourth intercostal space and the mid-axillary line (Correct answer)
Correct answer: The fourth intercostal space and the mid-axillary line
The phlebostatic axis is the correct reference point for leveling a transducer for hemodynamic monitoring. It is located at the intersection of the fourth intercostal space and the mid-axillary line. This position approximates the level of the right atrium, ensuring accurate pressure measurements.
CCRN - Review Hemodynamic Monitoring Questions and Answers 1
A patient in the ICU develops hypotension, tachycardia, and a decreased cardiac output.
The pulmonary artery catheter reveals the following readings: CVP 1 mmHg, PAWP 4 mmHg, and SVR 1800 dynes/sec/cm-5.
Which of the following conditions is the MOST likely cause of this hemodynamic profile?