Shock and Fluid Resuscitation Flashcards

Which type of shock is characterized by decreased cardiac output due to impaired myocardial contractility following blunt chest trauma?

Answer: Cardiogenic shock

Cardiogenic shock from blunt cardiac injury (myocardial contusion) results in decreased contractility and reduced cardiac output despite adequate intravascular volume.

During massive transfusion protocol, which electrolyte abnormality is most likely to cause cardiac arrest?

Answer: Hyperkalemia

Hyperkalemia from stored blood products (potassium leaks from aged RBCs) can cause fatal cardiac dysrhythmias including ventricular fibrillation and asystole during massive transfusion.

A trauma patient receiving crystalloid resuscitation develops worsening metabolic acidosis. Which crystalloid is LEAST likely to cause hyperchloremic acidosis?

Answer: Lactated Ringer's solution

Lactated Ringer's solution has a chloride concentration (109 mEq/L) closer to plasma (98-106 mEq/L) and contains lactate buffer, making it less likely to cause hyperchloremic metabolic acidosis compared to normal saline (154 mEq/L chloride).

Tranexamic acid (TXA) administration in trauma hemorrhage is most effective when given within what time frame from injury?

Answer: 3 hours

The CRASH-2 trial demonstrated that TXA reduces mortality from hemorrhage when administered within 3 hours of injury. Administration after 3 hours may increase mortality.

Which assessment finding differentiates obstructive shock from hypovolemic shock?

Answer: Distended neck veins are present in obstructive shock but flat in hypovolemic shock

Obstructive shock (cardiac tamponade, tension pneumothorax) presents with distended neck veins from impaired venous return to the heart, while hypovolemic shock presents with flat neck veins from volume depletion.

A trauma patient in hemorrhagic shock has received 4 units of PRBCs and remains hypotensive with a heart rate of 140. The next priority in the massive transfusion protocol is:

Answer: Continue balanced transfusion with plasma and platelets in a 1:1:1 ratio with PRBCs

Current evidence supports a balanced 1:1:1 ratio of PRBCs to plasma to platelets during massive transfusion to address both oxygen-carrying capacity and coagulopathy simultaneously.

The base deficit on an arterial blood gas is a useful marker in trauma because it indicates:

Answer: The severity of tissue oxygen debt and anaerobic metabolism

Base deficit reflects the degree of metabolic acidosis from tissue hypoperfusion and anaerobic metabolism, serving as a surrogate marker for the severity and duration of shock.

Which vasopressor is preferred as a first-line agent for trauma patients who remain hypotensive despite adequate volume resuscitation?

Answer: Norepinephrine

Norepinephrine is the preferred first-line vasopressor in trauma-related shock (after adequate volume resuscitation) due to its balanced alpha-1 and beta-1 effects, providing vasoconstriction and inotropy.

A patient with Class III hemorrhagic shock (30-40% blood volume loss) would be expected to present with which combination of findings?

Answer: Tachycardia 120-140, hypotension, tachypnea 30-40, confused and anxious

Class III hemorrhage (1,500-2,000 mL, 30-40% blood volume) presents with significant tachycardia, the first measurable drop in systolic blood pressure, marked tachypnea, and confusion.

Point-of-care viscoelastic testing (TEG/ROTEM) during trauma resuscitation is used to:

Answer: Guide goal-directed component therapy by assessing clot formation, strength, and breakdown in real-time

TEG (thromboelastography) and ROTEM (rotational thromboelastometry) provide real-time viscoelastic analysis of clot formation, strength, and fibrinolysis, enabling targeted blood component therapy.

Hypothermia in trauma patients worsens hemorrhage primarily by:

Answer: Impairing coagulation enzyme function and platelet aggregation

Hypothermia impairs the enzymatic reactions of the coagulation cascade and reduces platelet adhesion and aggregation, significantly worsening hemorrhage.

Damage control resuscitation in trauma includes all of the following EXCEPT:

Answer: Targeting a normal blood pressure of 120/80 mmHg before surgery

Damage control resuscitation intentionally accepts a lower-than-normal blood pressure (permissive hypotension with SBP 80-90 mmHg) until surgical hemorrhage control is achieved, rather than targeting normotension.