Hemodynamic Monitoring and Shock Management Flashcards

When performing thermodilution cardiac output measurement via pulmonary artery catheter, the cold saline injectate is administered into which port?

Answer: Right atrial (proximal) port

Cold saline is injected into the proximal right atrial port so the thermistor at the catheter tip can detect the downstream temperature change and calculate cardiac output via the Stewart-Hamilton equation.

In neurogenic shock following high spinal cord injury, which hemodynamic pattern is MOST characteristic?

Answer: Low SVR, bradycardia, and low CO

Neurogenic shock results from loss of sympathetic tone, producing vasodilation (low SVR) and loss of cardiac acceleration (bradycardia), distinguishing it from other distributive shock states.

Per the Surviving Sepsis Campaign, what is the recommended initial crystalloid fluid resuscitation volume and time frame for sepsis-induced hypoperfusion?

Answer: 30 mL/kg within 3 hours

The SSC recommends administering at least 30 mL/kg of IV crystalloid within the first 3 hours for patients with sepsis-induced hypoperfusion or septic shock.

For a patient with cardiogenic shock and adequate intravascular volume, which hemodynamic intervention is MOST appropriate?

Answer: Initiate inotropic support with dobutamine

Dobutamine improves myocardial contractility and cardiac output in cardiogenic shock with adequate preload; giving additional fluids risks worsening pulmonary edema.

At the cellular level, shock is BEST defined as:

Answer: Inadequate oxygen delivery relative to cellular metabolic demands

Shock is fundamentally a state of cellular hypoxia in which oxygen delivery is insufficient to meet cellular metabolic requirements, regardless of whether blood pressure is measurably low.

Elevated serum lactate in shock states primarily reflects:

Answer: Anaerobic metabolism due to inadequate tissue oxygenation

Hyperlactatemia in shock indicates anaerobic glycolysis is occurring because cells lack sufficient oxygen to sustain aerobic cellular respiration, resulting in lactate accumulation.

A mechanically ventilated patient without cardiac arrhythmias has a stroke volume variation (SVV) of 18%. What does this value indicate?

Answer: The patient is likely fluid responsive

SVV >13% in mechanically ventilated patients without arrhythmias indicates fluid responsiveness, meaning cardiac output would increase with additional fluid loading.