What is a massive transfusion protocol?

A massive transfusion protocol (MTP) is a standardized, pre-activated plan for delivering large volumes of blood products rapidly to patients with life-threatening hemorrhage. It coordinates the blood bank, lab, and clinical teams to deliver balanced ratios of packed red blood cells (pRBC), fresh frozen plasma (FFP), and platelets.

What does the 1:1:1 ratio mean?

It describes approximately equal component proportions, not one apheresis platelet bag per red-cell unit. In PROPPR, a pool of 5–6 whole-blood-derived platelet units counted as one apheresis platelet dose. The trial found more hemostasis and fewer early deaths from exsanguination with 1:1:1, but no statistically significant difference in 24-hour or 30-day all-cause mortality.

When should MTP be activated?

MTP is typically activated when a patient is predicted to receive more than 10 units of pRBC in 24 hours, has ongoing hemodynamic instability despite initial resuscitation, shows signs of coagulopathy, or meets trauma scoring criteria such as the ABC score ≥ 2.

Does this calculator replace clinical judgment?

No. This tool is for educational and estimation purposes only. Blood product decisions must be made by qualified clinicians using real-time lab values (TEG/ROTEM, CBC, coagulation studies), patient vitals, and institutional MTP protocols.

What is cryoprecipitate and when is it used?

Cryoprecipitate is a blood product rich in fibrinogen and factor VIII. It is given when fibrinogen falls below 1.5 g/L (150 mg/dL). Some MTP protocols include a fixed cryoprecipitate pack alongside each MTP round; this calculator shows it as an optional add-on.

Massive Transfusion Protocol Ratio Calculator

Select protocol ratio and pack count to calculate pRBC:FFP:platelet component quantities for massive transfusion protocol planning.

Protocol Parameters

MTP Ratio Protocol

6 : 6 : 1

pRBC : FFP : apheresis dose

6 : 3 : 1

RBC-heavy adult pack

Clinical Scenario

Include cryoprecipitate (10-unit pool)

Indicated when fibrinogen < 1.5 g/L; often given with pack 1.

Cumulative Transfusion Requirements

—

pRBC

units

—

FFP

units

—

Platelets

apheresis units

Cumulative Component Summary

Product	Units	Volume (approx.)
Total	—	— mL

Effective Ratio

—

pRBC

—

FFP

—

Plt

Clinical disclaimer: This calculator is for educational estimation only. All blood product decisions must be guided by real-time laboratory values (CBC, coagulation studies, TEG/ROTEM), patient vitals, and your institution's MTP protocol. Consult your blood bank and attending physician.

Select protocol parameters and click Calculate to see MTP requirements.

Summary

This educational calculator compares adult fixed-pack component quantities. It expresses platelets as adult apheresis doses (one dose is approximately equivalent to a pool of 5–6 whole-blood-derived platelet units), preventing unlike units from being treated as one-for-one. It does not calculate pediatric or weight-based dosing; always follow the institution's live MTP protocol and blood bank instructions.

How it works

Select an adult fixed-pack composition: 6:6:1 balanced or 6:3:1 RBC-heavy (pRBC:FFP:apheresis platelet doses).
Choose the clinical scenario to set the target transfusion pack count.
Review the calculated units of pRBC, FFP, and platelets.
Use the summary table to review cumulative blood component requirements.

Use cases

Trauma resuscitation requiring massive transfusion activation.
Major surgical hemorrhage with anticipated large blood loss.
Obstetric hemorrhage with hemodynamic instability.
Emergency department rapid hemorrhage control planning.
Blood bank coordination and pre-ordering for MTP activation.
Teaching and simulation for trauma and critical care teams.

Frequently Asked Questions

Last updated: 2026-06-19 · Reviewed by Nham Vu