What is the approach to blood component therapy in a patient with significant bleeding due to trauma or surgery, considering their condition, past medical history, and laboratory parameters such as hemoglobin levels, platelet count, and coagulation studies?

Blood Component Therapy in Trauma and Surgical Bleeding

Immediate Hemorrhage Control and Resuscitation Strategy

In patients with significant bleeding from trauma or surgery, immediately activate massive transfusion protocol with 1:1:1 ratio of RBC:FFP:platelets, administer tranexamic acid 1g IV within 3 hours of injury, and prioritize surgical hemorrhage control over laboratory-guided therapy. 1, 2

Damage Control Resuscitation Principles

Early hemorrhage control is paramount:

• Use temporary hemostatic devices (pressure, tourniquets) followed immediately by surgical or interventional radiological control 1
• Do not delay surgery for laboratory results—immediate hemorrhage control takes priority 2

Permissive hypotension during active bleeding:

• Maintain minimum acceptable preload without attempting to normalize blood pressure 1
• Avoid vasopressors during active hemorrhage 1
• Modify approach in traumatic brain injury or spinal cord injury 1

Avoid crystalloid and colloid administration:

• Do not use clear fluids for volume resuscitation during uncontrolled hemorrhage unless profound hypotension exists with no imminent blood product availability 1
• Crystalloids worsen dilutional coagulopathy and hypothermia 2

Blood Component Administration Protocol

Red Blood Cells (RBC)

• Administer RBC in 1:1 ratio with FFP during active hemorrhage 1
• Transfusion rarely indicated when hemoglobin >10 g/dL, almost always indicated when <6 g/dL in stable patients 3
• In massive bleeding, deliver empirically first, then use point-of-care testing to guide therapy 1

Fresh Frozen Plasma (FFP)

Indications during major hemorrhage:

• Administer FFP in 1:1 ratio with RBC during ongoing bleeding 1
• Use when INR >1.5 in actively bleeding patients 1
• Dose: 10-15 ml/kg 1
• FFP contains all coagulation factors but provides only ~2g fibrinogen per 4 units 4

Cryoprecipitate

Administer cryoprecipitate when fibrinogen is critically low:

• Give two pools (10 units total) empirically during massive transfusion until test results available 1, 4
• Target fibrinogen >1.5 g/L during major hemorrhage (>2.0 g/L in obstetric hemorrhage) 1, 4
• Each pool contains at least 2g fibrinogen—far more efficient than FFP for fibrinogen replacement 4
• Administer when fibrinogen <1.0 g/L with significant bleeding risk before procedures 1, 4

Platelets

Maintain platelet count >50 × 10⁹/L during active bleeding:

• Administer one adult therapeutic dose empirically during massive transfusion 1
• Target >100 × 10⁹/L in traumatic brain injury, multiple trauma, or spontaneous intracerebral hemorrhage 1
• Target >75 × 10⁹/L after cardiopulmonary bypass due to platelet dysfunction 1
• Prophylactic transfusion ineffective when thrombocytopenia due to increased destruction 3

Tranexamic Acid Administration

Give tranexamic acid 1g IV immediately in trauma patients:

• Administer within 3 hours of injury to reduce mortality 1, 2
• Follow with 1g over 8 hours 2
• Avoid if >3 hours post-injury unless point-of-care testing shows ongoing hyperfibrinolysis 1

Laboratory and Point-of-Care Testing

Use point-of-care testing to guide therapy once available:

• Viscoelastic testing (TEG/ROTEM) recommended over traditional PT/APTT for real-time coagulation assessment 1
• Traditional PT/APTT have slow turnaround and were not designed for hemorrhage monitoring 1
• Point-of-care testing provides shorter turnaround time and more relevant global coagulation status 1

Key laboratory targets once bleeding controlled:

• Fibrinogen >1.5 g/L (>2.0 g/L obstetric) 1, 4
• Platelet count >50 × 10⁹/L (>100 × 10⁹/L in brain/multiple trauma) 1
• INR <1.5 1

Critical Pitfalls to Avoid

Do not delay surgical hemorrhage control for laboratory results:

• Immediate operative intervention takes priority over laboratory-guided resuscitation 2
• Deliver blood products empirically during active bleeding 1

Do not attempt to normalize blood pressure with crystalloids:

• Causes hemodilution, hypothermia, and clot disruption 2
• Use blood products for volume replacement during hemorrhage 1

Do not withhold tranexamic acid if within 3-hour window:

• Must be given within 3 hours of injury to reduce mortality 1, 2
• Withholding represents missed opportunity for mortality reduction 2

Do not use FFP alone for fibrinogen replacement:

• Cryoprecipitate provides 4g fibrinogen per two pools versus only 2g from four units FFP 4
• More efficient and avoids volume overload 4

Temperature Management

Maintain normothermia aggressively:

• Apply measures to reduce heat loss and warm hypothermic patients 1
• Children particularly at risk of hypothermia during rapid blood product administration 1
• Hypothermia worsens coagulopathy as part of the "lethal triad" 2