8.2 Blood Products in Flight
Key Takeaways
- Whole blood or a near 1:1:1 red-cell, plasma, and platelet ratio replaces what the bleeder is losing; crystalloid does not carry oxygen or clot.
- Tranexamic acid is typically 1 g early (CRASH-2 / current trauma teaching) and is not started after 3 hours from injury.
- Citrate in stored blood binds ionized calcium—replace calcium after transfusion and warm every unit you hang.
- Stop a suspected transfusion reaction, keep the intravenous line, and treat anaphylaxis, transfusion-associated circulatory overload, or transfusion-related acute lung injury; do not finish the unit.
- The cooler chain, unit numbers, and Rh status in pregnancy are part of the flight product, not paperwork after landing.
Blood is the resuscitation fluid for hemorrhagic shock. Domain 2.C.1 of the August 2026 Certified Flight Registered Nurse (CFRN) outline lists blood products next to crystalloid because hanging saline into a bleeder is dilution, not resuscitation. The cabin adds cold, time, and a cooler you must keep closed. Know what is in each bag, when to give tranexamic acid (TXA), why calcium disappears, and what to do when the patient wheezes mid-unit.
Whole blood versus a 1:1:1 component ratio
Program products and the balanced ratio
Low-titer group O whole blood (LTOWB) gives red cells, plasma, and platelets in one bag that resembles what the patient just lost. Walking-blood-bank programs draw fresh whole blood from a screened donor—sometimes a crew member—under a written protocol. Both are program-dependent. If your aircraft does not carry whole blood and has no walking-blood-bank protocol, do not invent one on the ramp. Use the components you have and fly to blood.
When you have components, current trauma teaching aims at a balanced 1:1:1 ratio of packed red blood cells (PRBCs), plasma, and platelets rather than a cooler of red cells and no clotting factors. That ratio is clinical teaching, not a Board of Certification for Emergency Nursing (BCEN)-owned formula.
| Product | What it replaces | Flight note |
|---|---|---|
| Whole blood (often LTOWB) | Red cells, plasma, and platelets | Ideal scene product if stocked; still needs warming and calcium |
| PRBCs | Oxygen-carrying red cells | Alone, you have oxygen and no clot |
| Plasma (fresh frozen or liquid) | Clotting factors and volume | Liquid plasma is the usual flight-ready form |
| Platelets | Platelet plug | Do not freeze; vibration is not a reason to skip them |
| Cryoprecipitate (cryo) | Fibrinogen, factor VIII, von Willebrand factor, factor XIII | Use when fibrinogen is low or thromboelastography (TEG) / rotational thromboelastometry (ROTEM) shows a weak clot |
If the sending hospital already started TEG or ROTEM, take the tracing and the last fibrinogen with you. Without a viscometer, still give balanced products rather than guessing from a single hematocrit.
Massive transfusion is a clinical trigger: ongoing hemorrhage plus shock that will consume a large share of circulating volume. Hypotension, a falling end-tidal carbon dioxide (ETCO2), a positive focused assessment with sonography for trauma (FAST), a pelvic binder, or a non-compressible junctional bleed is enough to start the ratio you have. Do not wait for a hemoglobin of 6 g/dL at 3,000 feet.
TXA, calcium, and warming
Early antifibrinolysis and the trauma diamond
Clinical Randomisation of an Antifibrinolytic in Significant Haemorrhage 2 (CRASH-2) and current trauma teaching support TXA 1 g given early—typically the first gram over about 10 minutes, often followed by a second gram if the receiving protocol uses that schedule. The exam idea is early, not late. Benefit clusters in the first 3 hours after injury. Starting TXA after 3 hours is associated with harm in that evidence base; do not give a late dose because the flight is long. TXA is not a substitute for plasma, platelets, or a surgeon.
Stored blood is anticoagulated with citrate, which binds ionized calcium. Hypocalcemia is a coagulopathy—the fourth corner of the trauma diamond. Replace calcium after transfusion with calcium chloride or calcium gluconate per program dose. Do not mix calcium in the same lumen as PRBCs. Recheck ionized calcium if you have a cartridge; treat empirically if the cooler is emptying and you do not.
Warm every unit. A 4 °C bag is iatrogenic hypothermia. Use the aircraft blood warmer. Never microwave a unit or leave it on the glare shield. If the warmer fails, still give indicated blood and fight heat loss every other way you have.
Reactions, the cooler, and Rh
Stop the unit, keep the line
A transfusion reaction in a vibrating cabin is easy to mislabel as "just shock." New fever, urticaria, wheeze, flash pulmonary edema, or a saturation crash out of proportion to the bleed should make you stop the product.
- Stop the unit. Do not finish it to raise the hemoglobin.
- Keep the intravenous line. Hang saline through the same catheter.
- Treat the syndrome in front of you. Anaphylaxis gets intramuscular epinephrine. Transfusion-associated circulatory overload (TACO) is hydrostatic pulmonary edema—oxygen, sit the patient up if you can, consider ventilation, and diurese if the tank is now too full. Transfusion-related acute lung injury (TRALI) is permeability edema; support gas exchange and do not treat it as simple volume overload. Save the bag and tubing.
The carry-on cooler is a regulated storage device. Check temperature indicators before you accept units. Document donor numbers, product type, start and stop times, volume, and any reaction. Hand the empties to the receiving blood bank.
Rh (D) status matters in anyone who can become pregnant. Type-specific product is ideal. Uncrossmatched O-negative red cells remain the classic emergency choice for that group when type-specific blood is not aboard. Some programs use low-titer O-positive whole blood under a written risk protocol—that is program policy, not a reason to ignore Rh. If you give Rh-positive product to an Rh-negative person who can become pregnant, document it so the receiving team can plan Rh immunoglobulin (RhoGAM) follow-up. Pregnancy does not make you withhold a life-saving unit; it makes you choose the least alloimmunizing product you actually have.
A scene trauma patient is 40 minutes from injury. The aircraft carries tranexamic acid and the first unit of blood is hanging. Which tranexamic acid plan matches CRASH-2 / current trauma teaching?
After several units of blood in flight, ionized calcium is low and oozing continues. What is the mechanism you are treating?
Mid-unit, a previously stable interfacility patient develops urticaria, wheeze, and a falling saturation. What is the immediate transfusion-reaction sequence?