Fluid Resuscitation and Blood Products in the Critical Patient Practice Questions

25 multiple-choice questions on Fluid resuscitation and blood products in the critical patient for paramedic and EMT students, from Chapter 41 (Management and Resuscitation of the Critical Patient). Read each question, pick your answer, then tap Show answer to check it and read the explanation.

25 practice questions

1. You are about to transfuse a unit of red cells, and the only fluid hanging is lactated Ringer's. Why should you not run the blood through the same line?

   1. A. Its calcium can make the stored blood clot
   2. B. Its lactate destroys the red blood cells
   3. C. Its potassium causes dangerous hyperkalemia
   4. D. Its sugar makes the red blood cells swell
   Show answer

   Answer: A. Its calcium can make the stored blood clot

   Stored blood contains citrate as an anticoagulant, and the calcium in lactated Ringer's can overcome it and form clots in the line. Blood is given through its own line or with normal saline only. Solutions containing dextrose, such as D5W, are also avoided because they can make red cells swell and burst.

2. A 68-year-old on hemodialysis is in septic shock with clear lungs and a BP of 78/42 mmHg. The best initial fluid approach is to:

   1. A. Give 250 to 500 mL boluses and recheck the lungs
   2. B. Withhold fluid entirely because she makes no urine
   3. C. Give 30 mL/kg as a single rapid infusion
   4. D. Give D5W, to avoid adding any more sodium
   Show answer

   Answer: A. Give 250 to 500 mL boluses and recheck the lungs

   Kidney failure is not a reason to withhold fluid from a patient in septic shock with clear lungs, but she cannot excrete extra volume, so fluid is given in smaller boluses with reassessment of lung sounds, oxygenation, and perfusion after each, and a vasopressor is started early if she stays hypotensive. Withholding fluid entirely leaves possible hypovolemia untreated. A single large rapid infusion risks pulmonary edema that only dialysis can remove. D5W is hypotonic and leaves the vessels quickly, so it does not restore circulating volume.

3. A 70-kg man in septic shock is hypotensive with clear lungs. Using the Surviving Sepsis target, about how much crystalloid should he receive in the first 3 hours?

   1. A. 0.7 L
   2. B. 2.1 L
   3. C. 4.2 L
   4. D. 7.0 L
   Show answer

   Answer: B. 2.1 L

   At 30 mL/kg, a 70-kg patient needs about 2,100 mL, given in boluses with reassessment of lungs, perfusion, and blood pressure. The 0.7 L figure reflects 10 mL/kg, which is underresuscitation.

4. For crystalloid resuscitation of most critically ill adults, current evidence favors:

   1. A. 5% dextrose in water given at a high rate
   2. B. Half-normal saline to reduce the sodium load
   3. C. A balanced solution like lactated Ringer's
   4. D. Hypertonic 3% saline for every patient
   Show answer

   Answer: C. A balanced solution like lactated Ringer's

   Balanced crystalloids such as lactated Ringer's or Plasma-Lyte are associated with fewer kidney complications than large volumes of saline. D5W and half-normal saline are hypotonic, leave the vessels quickly, and can worsen cerebral edema.

5. After each fluid bolus in a shocked patient, the most important step is to:

   1. A. Give a second bolus immediately without reassessing
   2. B. Start a vasopressor regardless of the response
   3. C. Wait 30 minutes before checking the vital signs
   4. D. Reassess perfusion and the lungs before giving more
   Show answer

   Answer: D. Reassess perfusion and the lungs before giving more

   Fluid should be given as a series of boluses, each followed by reassessment of mental status, pulse, blood pressure, skin, and lung sounds. Giving more without reassessment risks fluid overload, especially in older or cardiac patients.

6. A 75-year-old woman with sepsis has received 1.5 L of crystalloid. She is now more short of breath with new crackles and an SpO2 drop from 95% to 88%. You should:

   1. A. Stop the fluid and consider a vasopressor
   2. B. Give a further 1 L bolus to raise the pressure
   3. C. Switch to normal saline and keep infusing
   4. D. Give furosemide and continue the bolus
   Show answer

   Answer: A. Stop the fluid and consider a vasopressor

   New crackles and falling saturation mean she is no longer fluid-tolerant, so more volume will worsen pulmonary edema; vasopressors can support pressure instead. Simply switching crystalloid type does not change the volume problem.

7. A passive leg raise is used during resuscitation to:

   1. A. Treat hypotension as a substitute for any fluid bolus
   2. B. Predict whether the patient will respond to fluid
   3. C. Reduce pulmonary edema by pooling the blood
   4. D. Measure the central venous pressure directly
   Show answer

   Answer: B. Predict whether the patient will respond to fluid

   Raising the legs to 45 degrees returns about 300 mL of venous blood to the chest; if stroke volume or pressure rises, the patient is likely fluid-responsive. The effect is temporary, so it is a test rather than a treatment.

8. For a 68-year-old in cardiogenic shock with clear lungs and a BP of 82/56 mmHg, fluid, if given, should be:

   1. A. A rapid 2-liter bolus through two large-bore lines
   2. B. Withheld entirely, regardless of the lung findings
   3. C. A small bolus of about 250 mL with lung checks
   4. D. A 30 mL/kg bolus, as in a patient with septic shock
   Show answer

   Answer: C. A small bolus of about 250 mL with lung checks

   A cautious small bolus is reasonable when the lungs are clear, because some cardiogenic patients are relatively volume-depleted; you stop at the first sign of congestion. Large boluses overwhelm a failing ventricle and cause pulmonary edema.

9. A 3-year-old weighing 15 kg is in septic shock with a delayed capillary refill and HR 180. The appropriate initial fluid bolus is:

   1. A. 50 mL of D10W over 20 minutes
   2. B. 600 mL of isotonic crystalloid over an hour
   3. C. 1,000 mL of lactated Ringer's
   4. D. 150 to 300 mL of isotonic crystalloid
   Show answer

   Answer: D. 150 to 300 mL of isotonic crystalloid

   Pediatric shock is treated with 10 to 20 mL/kg boluses of isotonic crystalloid, here 150 to 300 mL, with reassessment after each. D10W treats hypoglycemia but is not a resuscitation fluid.

10. You must give blood as fast as possible by gravity. Which access will allow the highest flow?

    1. A. A 20-gauge, 1-inch IV in the hand
    2. B. An 18-gauge, 8-inch midline catheter
    3. C. A 14-gauge, 1.25-inch peripheral IV
    4. D. A 16-gauge, 2-inch IV with microdrip tubing
    Show answer

    Answer: C. A 14-gauge, 1.25-inch peripheral IV

    Flow through a catheter rises with the fourth power of its radius and falls with its length, so a short, large-bore peripheral catheter (14 gauge) gives the fastest flow; a pressure bag at about 300 mmHg and macrodrip or blood tubing add more. A 20-gauge catheter is far narrower. A long midline catheter adds resistance along its length even at 18 gauge. A microdrip set restricts flow no matter how large the catheter.

11. Before you start a unit of prehospital blood, the most important safety step is to:

    1. A. Prime the tubing with D5W to keep the cells moving
    2. B. Double-check the unit and patient with a partner
    3. C. Premedicate with diphenhydramine before the unit
    4. D. Run it through standard tubing without a filter
    Show answer

    Answer: B. Double-check the unit and patient with a partner

    Most serious transfusion reactions come from giving the wrong unit to the wrong patient, so the product label, expiration, and the patient's identity or emergency ID band are checked by two people before the unit is spiked, and the check is documented. D5W makes red cells clump and hemolyze; only normal saline is compatible. Premedicating with diphenhydramine does not prevent the hemolytic reaction caused by a wrong unit and is not routine. Blood is given through filtered blood tubing, because the filter catches clots and debris that standard tubing would let through.

12. During a rapid, massive transfusion in an infant, the monitor suddenly shows tall, peaked T waves. The most likely source of the problem is:

    1. A. Calcium carried in the citrate preservative
    2. B. Sodium in the saline used to prime the line
    3. C. Lactate added to the plasma during storage
    4. D. Potassium leaked from the stored red cells
    Show answer

    Answer: D. Potassium leaked from the stored red cells

    Potassium leaks out of red cells during storage, and rapid or massive transfusion, especially in infants or patients with kidney failure, can deliver enough to cause hyperkalemia with peaked T waves, a wide QRS, and arrest. Citrate binds calcium and lowers it rather than adding any. Give calcium to protect the heart and slow the transfusion.

13. In balanced massive transfusion, packed red cells, plasma, and platelets are given in a ratio of about:

    1. A. 1:1:1
    2. B. 3:1:0
    3. C. 1:3:1
    4. D. 4:1:4
    Show answer

    Answer: A. 1:1:1

    Hemostatic resuscitation gives red cells, plasma, and platelets in roughly equal ratios to replace what is lost in whole blood. Giving red cells alone, as in a 3:1:0 ratio, leaves the patient coagulopathic.

14. A septic 60-year-old receives a 500-mL bolus. Her HR falls from 128 to 110, her mentation improves, her lungs stay clear, and her BP is 90/56 mmHg. You should next:

    1. A. Stop fluid because she has fully recovered
    2. B. Give another bolus, then reassess her lungs
    3. C. Give furosemide now to prevent fluid overload
    4. D. Start a pressor and give no more fluid
    Show answer

    Answer: B. Give another bolus, then reassess her lungs

    She responded to the first bolus (slower heart rate, clearer thinking) and still has clear lungs and a soft pressure, so she is both fluid-responsive and fluid-tolerant; another bolus with reassessment is appropriate, adding a vasopressor if pressure stays low despite fluid. Stopping now leaves her under-resuscitated. Furosemide would remove volume she still needs. Abandoning fluid for a pressor while she is still responding skips a cheap, effective step.

15. A 0.45% saline or D5W infusion is a poor choice for restoring circulating volume in shock mainly because:

    1. A. It causes too much sodium to build up
    2. B. It stays inside the vessels for many hours
    3. C. It cannot be given through an IO needle
    4. D. Most of the free water moves into cells
    Show answer

    Answer: D. Most of the free water moves into cells

    Hypotonic fluids and D5W (once the glucose is used) behave like free water, which spreads across all body compartments, so only a small fraction stays in the vessels. They also lower serum sodium and can worsen brain swelling. Isotonic crystalloid or blood is used to restore volume.

16. Albumin and other colloids are not routinely preferred over crystalloids in prehospital resuscitation mainly because they:

    1. A. Have not shown better survival and cost more
    2. B. Cause severe hypernatremia in most patients
    3. C. Leave the vessels faster than crystalloids do
    4. D. Cannot be given through an IV or IO line
    Show answer

    Answer: A. Have not shown better survival and cost more

    Large trials found no survival advantage for albumin over saline in mixed ICU patients, and synthetic starches increased kidney injury. Colloids actually stay in the vessels longer than crystalloids, so that is not the reason.

17. For a rapid infusion, a pressure infuser around a bag of crystalloid is usually inflated to about:

    1. A. 30 mmHg
    2. B. 100 mmHg
    3. C. 300 mmHg
    4. D. 1,000 mmHg
    Show answer

    Answer: C. 300 mmHg

    Pressure infusers are inflated to about 300 mmHg, which is well above venous pressure and greatly speeds flow through a large catheter. Lower pressures add little over gravity, and the bag and tubing are not designed for much higher pressures. Watch the gauge, since pressure falls as the bag empties.

18. Your service carries only Rh-positive group O blood, with no Rh-negative units. For which bleeding patient is it the most straightforward choice?

    1. A. A 22-year-old woman with a chest stab wound
    2. B. A 45-year-old man with an unstable pelvis
    3. C. A 30-year-old pregnant woman in a crash
    4. D. A 16-year-old girl with a femur fracture
    Show answer

    Answer: B. A 45-year-old man with an unstable pelvis

    Group O blood avoids most ABO incompatibility, but an Rh-positive unit can sensitize an Rh-negative female, risking hemolytic disease in a future pregnancy. For men and for women past childbearing age that risk does not apply, so it is the straightforward choice. Many programs still give Rh-positive blood to females of childbearing potential when Rh-negative product is unavailable and the bleeding is life-threatening, because the risk of death outweighs the small risk of sensitization, but that is a protocol decision. The other three patients are females of childbearing potential, including a pregnant woman, for whom Rh-negative product is preferred.

19. In a ventilated patient with fixed ventilator settings, the ETCO2 rises from 30 to 34 mmHg during a passive leg raise. This suggests:

    1. A. The patient is now being overventilated
    2. B. More fluid would most likely cause pulmonary edema
    3. C. The tube has moved into the esophagus
    4. D. Cardiac output rose, so fluid will likely help
    Show answer

    Answer: D. Cardiac output rose, so fluid will likely help

    With ventilation held constant, ETCO2 follows pulmonary blood flow, so a rise of more than about 5% during a passive leg raise means the transfused venous blood increased cardiac output and the patient is likely to respond to a fluid bolus. Overventilation would lower, not raise, ETCO2. A rise in output with leg raising argues for, not against, fluid responsiveness, though the lungs must still be watched. Esophageal placement gives a flat or near-absent waveform.

20. During resuscitation of septic shock, which bedside finding is a useful perfusion target that can change within minutes?

    1. A. Lactate returning to normal within 5 minutes
    2. B. Urine output measured over the first 10 minutes
    3. C. Capillary refill time returning toward normal
    4. D. A temperature that falls below 38 °C (100.4 °F)
    Show answer

    Answer: C. Capillary refill time returning toward normal

    Capillary refill responds within minutes to improved flow, and the ANDROMEDA-SHOCK trial found that targeting refill was at least as good as targeting lactate; the Surviving Sepsis guideline suggests using it as an adjunct. Lactate clears over hours, not minutes. Urine output is meaningful only over an hour or more and is not measured in the field. Lowering fever is not a resuscitation target and does not show that perfusion is restored.

21. A patient on norepinephrine now has a MAP of 70 mmHg, but her skin is cold and mottled and she is less responsive than before. This means that:

    1. A. Her perfusion is still poor despite the MAP
    2. B. Resuscitation is complete at this MAP
    3. C. The mottling is an expected effect of the pressor
    4. D. The pressor can be stopped at this MAP
    Show answer

    Answer: A. Her perfusion is still poor despite the MAP

    A MAP target is a means, not the goal: worsening mental status and spreading mottling show that her tissues are still underperfused, so look for unaddressed hypovolemia, low cardiac output, or a missed source, and reassess the plan. Declaring resuscitation complete on the number alone ignores the clinical signs. Mottling is a sign of poor perfusion, not an expected drug effect, though very high pressor doses can cause peripheral ischemia. Stopping the pressor would drop her pressure further.

22. A 55-year-old in septic shock has received 1 L of crystalloid. Which change best shows that perfusion is improving?

    1. A. A rising respiratory rate with new crackles
    2. B. Improving mental status and warmer skin
    3. C. Increasing mottling across the knees
    4. D. A falling ETCO2 with steady ventilation
    Show answer

    Answer: B. Improving mental status and warmer skin

    Clearer mentation, warmer skin, a stronger pulse, and a falling heart rate indicate improved perfusion. A falling ETCO2 with constant ventilation suggests worsening cardiac output, not improvement.

23. A 25-year-old with an uncontrolled stab wound to the groin is hypotensive. With limited hands, the measure most likely to raise his pressure is:

    1. A. Running two liters of crystalloid wide open
    2. B. Giving push-dose epinephrine every 2 minutes
    3. C. Raising both legs while he lies flat
    4. D. Packing the wound and holding firm pressure
    Show answer

    Answer: D. Packing the wound and holding firm pressure

    Pressure falls because blood is leaving the vessels, so stopping the loss comes first: a junctional wound in the groin cannot take a limb tourniquet, but it can be packed with gauze (hemostatic if available) and held with firm direct pressure, then a junctional device used if carried. Large crystalloid volumes dilute clotting factors and raise pressure only briefly while bleeding continues. Vasopressors do not replace lost volume and can worsen ischemia in hemorrhage. Leg raising gives only a small, temporary shift of blood.

24. Your service carries whole blood. A 20-kg child is in hemorrhagic shock after being run over. A reasonable first transfusion volume is:

    1. A. 1 to 2 mL/kg, or 20 to 40 mL
    2. B. One full adult unit of about 500 mL
    3. C. 10 to 20 mL/kg, or 200 to 400 mL
    4. D. 60 mL/kg, or 1,200 mL, before reassessing
    Show answer

    Answer: C. 10 to 20 mL/kg, or 200 to 400 mL

    Pediatric blood products are dosed by weight, usually 10 to 20 mL/kg per aliquot, with reassessment after each one. One to 2 mL/kg is far too little to matter, and 60 mL/kg approaches the child's whole blood volume (about 70 to 80 mL/kg) before any reassessment.

25. A 30-year-old woman with a ruptured ectopic pregnancy is pale with HR 140 and BP 70/40 mmHg. Your service carries O-negative packed red cells. The best choice is:

    1. A. Transfuse O-negative cells and transport rapidly
    2. B. Give 3 L of crystalloid before any transfusion
    3. C. Wait for the hospital to type and crossmatch
    4. D. Withhold blood because she is of childbearing age
    Show answer

    Answer: A. Transfuse O-negative cells and transport rapidly

    O-negative red cells are the safest emergency product for a woman of childbearing age and treat both volume and oxygen-carrying deficits. Waiting for a crossmatch or flooding her with crystalloid delays definitive treatment.