Published: 28 November 2023
What Is An MTP?
When a person has experienced a traumatic injury, there is a method of administering blood products executed known as Massive Transfusion Protocol or MTP. This is not the primary method of delivering blood to a patient, but rather is only used in urgent situations with major hemorrhaging. In this article, we will discuss the MTP procedure in detail. In addition, we will also give an overview of Routine Blood Issue and Emergency Release, to better help distinguish the differences.
Blood Component Issue Under Routine Conditions
The main section of the hospital that requests blood under routine issue protocol is the Operating Room (OR). And depending what type of surgery is being performed, will determine how much blood is requested. Minor procedures may require just 1 unit and more major surgeries often require several.
A few days before the surgery a request for blood products will be sent to the blood bank along with a blood sample. The sample’s serum will be used to confirm the patient’s ABO/Rh (blood type). The patient serum is also mixed with red blood cells from selected units to ensure they are compatible with each other. Since there is more reaction time during routine issue to perform pre-transfusion testing, this allows ABO type-specific red cells to be given and enables the type-O units to be saved for emergency issue or MTP.
Once the appropriate units are crossmatched, they are placed in a designated “Crossmatched” shelf until its picked up by the OR staff. According to FDA standards, this crossmatch is only valid for 72 hours. If blood pickup is delayed past that point, a new specimen will be required and a new crossmatch must be completed in order to maintain confirmation of compatibility.
This process is time consuming, but it works well in helping conserve type-O inventory, ensuring that units are fully compatible with recipients before issuing and eliminates the need for physicians to assume risk for “Untested Blood Products”.
Emergency Release
Emergency Issue of blood products is utilized as a bridge between Routine Issue and MTP. It requires issuing a small number of units similar to routine issue, but at a faster pace like an MTP. The departments who frequently request emergency release are the ER, Labor & Delivery and the OR and the typical order is usually limited to only 1 or 2 units.
Emergency releases are used when a doctor realizes there is an urgent need for blood, but not necessarily enough to warrant initiating an MTP. Due to the rapid need for these products, pre-transfusion testing is not performed. A courier will show up with a physician signed request form authorizing the release of untested blood. The form will also specify which blood products are needed, and can be either type-compatible or type-specific.
Notification of MTP
Massive Transfusion Protocol is used in ER trauma situations where there is massive amounts of hemorrhaging, usually due to gunshot/stab wounds as well as motor vehicle accidents. The process is similar to Emergency Issue in that blood is released without pre-transfusion testing being performed. However, the major difference is that the number of units released is much higher.
Notification of an MTP usually starts out on the hospital’s overhead speaker with a notification like “Trauma team to the trauma room” or “Trauma Level 1”. This gives the initial cue for the blood bank to call the ER to inquire of blood needs. ER staff will normally have an idea of the involved injuries and whether it will require blood products. If blood is required, they will let the blood bank know the age and gender, if known.
Knowing the age and gender of the trauma patient is vital because it is the deciding factor of whether O positive or O negative blood will be issued.
– Males of all ages and females who are past childbearing age (>50 years old) will receive O positive blood since it is ABO-compatible with all blood types and the Rh factor has less impact due to not contending with childbirth and Hemolytic Disease of the Newborn (HDN) risk.
– Females of childbearing age (< 50 years old) will receive O negative blood, since it is ABO-compatible and the negative Rh status will reduce HDN risk for any present or future pregnancies.
Upon initial contact with the ER, you will then be able to determine the answers to 2 important questions:
You will know if they need blood. Knowing this, will give you the cue to start the MTP process or not.
You will know the age and gender of the inbound patient, although in some cases, it may just be an estimate if first responders are unable to locate identification of the patient. This information helps determine the Rh status of the units that will be released. O positive donors are in much higher supply than O negative donors, so it is more critical to manage this appropriately in order to ensure that O negatives are in supply where they are truly needed.
Preparation of MTP Units
Regarding the quantities of each type of blood product, Massive Transfusion Protocol ratios vary slightly in between different facilities. Nevertheless, a common MTP guideline is to issue 4 Red Blood Cells (RBC), 4 Fresh Frozen Plasma (FFP) and either a Platelet (PLT) or Cryoprecipitate (Cryo). Each additional round will include the standard 4 RBC and 4 FFP units in addition to the Platelet and Cryo unit which usually rotates each time.
In between rounds, blood bank staff will thaw FFP into liquid plasma as well as thaw Cryoprecipitate. Paperwork will also be initiated to annotate any new selected units for the next round.
The courier will pick up the first round MTP pack from the blood bank and will usually give a heads up if a second or third round is needed. Regardless of the outlook, additional rounds of MTP packs will continue to be issued until either the patient is stable, or they have expired. The ER doctor in charge will make that final call.
Pickup From The Blood Bank
When the ER is ready to pickup the MTP pack, they will send a courier to the blood bank, usually a nurse to sign for the units.
When they ring the doorbell at the window, blood bank staff will greet them and have paperwork ready to sign. The ER courier should have brought trauma patient label stickers as well, so that each piece of paperwork can be quickly tied to the patient, without having to waste time handwriting the information. A common pitfall with some couriers is that they don’t bring enough labels. There are several copies of paperwork to be filled out, with each typically having 3 copies of carbon paper each, so bringing extra labels can help reduce the chance that the lab staff will need to transcribe information and slow down the process.
The MTP paperwork is essentially the same as “Emergency Release” and states that the units being released are “Untested” due to time constraints and that the benefits of receiving the blood outweigh the risk of it not being tested before-hand (Type & Screen, Crossmatch). By signing this paperwork, the physician of the patient assumes this risk. Each paper will have all product numbers, blood types and product codes listed for all units in that pack. The courier will sign/date the “person picking up” block and the blood bank tech will sign/date the “person issuing” block.
Transport of Units After Issue
Once the paperwork is signed, the units are placed in coolers and handed over to the courier. The coolers help to maintain the temperature of the units while in transport. When RBCs, liquid plasma, or cryoprecipitate are being moved, their coolers will have ice packs and must stay between 1-10 Celsius. If cold storage platelets are being moved, they will have ice packs as well and must also stay between 1-10 Celsius. If room temperature platelets are being moved, they will be in a separate cooler and must stay between 20-24 Celsius.
Sometimes, the units get to the ER and its decided that some or all of them are not needed anymore, due to a change in the patient’s prognosis. In this case, the units can be returned back to the blood bank as long as they have remained at the proper storage temperature. However, if the blood bank takes the temperature and it is out of range, the units must be quarantined and destroyed.
MTP Transfusion Process
Once the units get back to the ER, they will usually grab the first unit and begin transfusion immediately. The remaining units will stay in the cooler until they are ready to be spiked, so that they can maintain proper temperature while waiting. Each RBC unit should have a TempDot which changes colors according to temperature. If the TempDot is white in the middle, the unit is still within range, but if it has turned red, the unit has gotten too warm and should not be used.
Before the first unit is transfused, a set of baseline vitals (temperature, pulse & blood pressure) is taken and annotated on the transfusion form.
The blood unit is then hung and transfused into the patient. Sometimes two lines are run at once so products can be pushed in even faster.
Each blood unit has a transfusion form associated with it and needs to be filled out real-time as the unit is being transfused. Sometimes, multiple products with the same product code can be consolidated to the same form in order to minimize transcription time (i.e. 4 RBCs on the same form, instead of 4 separate forms for each unit).
During the transfusion, the patient is observed for any sort of negative reaction (urticaria, fever, chills, pain) and is annotated if present. Once the MTP pack is close to being used up, a courier will be sent to pick up any subsequent rounds after that, until the doctor in charge calls it.
Once the doctor calls the MTP, the volume given and the time the transfusion was stopped or interrupted is annotated on the last transfusion form. Lastly, a set of post-transfusion vitals is taken so that it can be compared to the pre-transfusion vitals.
Once the transfusion is complete, a copy of the transfusion form is returned back to the blood bank with any unused units.
ER Stored Blood Units
Some Emergency Rooms are stocked with their own supply of blood products. This is usually a small quantity of units and is primarily used to get a head start while the MTP pack is being transported from the blood bank.
Units that are stored in the ER are typically either Type O RBCs or Low Titer O Whole Blood (LTOWB).
If there is an ER Stat Lab, the lab techs may be the ones responsible for issuing the units to ER nursing staff. However, some ERs have the capability to issue to themselves.
The blood bank is responsible for managing the inventory of ER stored units. They track the quantity and expiration dates of each unit and switch them out with fresh units once they get close to their expiration or when they get used up with a patient.
The use of ER stored blood products can greatly increase survival rates of critically injured patients due to the speed of access.
MTP Therapeutic Goal
The goal of hemotherapy is to increase tissue oxygenation and restore clotting ability. Both of these components require specific blood components to accomplish each objective.
Tissue Oxygenation
Red blood cells are used to transport oxygenated blood from the lungs to tissues throughout the body. RBCs also transport carbon dioxide away from tissues back to the lungs. When someone losses massive amounts of red blood cells, their tissues suffer from lack of oxygen. The key metrics used to measure this oxygen carrying capacity are the Hemoglobin and Hematocrit, often ran as part of a Complete Blood Count (CBC). Accordingly, a general rule for red blood cells is that for every unit of RBCs that is transfused, the patient’s hemoglobin is raised by 1 g/dL and the hematocrit is raised by 3%. The level of deficiency with these can be a guide for the number of red cells that the doctor needs to order.
Clotting Restoration
The body’s ability to clot is made possible with the synergy of clotting factors and platelets. A clot happens when platelets aggregate together to form a plug. This plug is strengthened with the addition of fibrin, which is a product of the coagulation cascade. In order to help boost the numbers of platelets available to make a plug, platelets are transfused. To replace lost coagulation factors, FFP and Cryoprecipitate are transfused.
There are times where each of these individual components need to be transfused on their own for certain situations or disease states. But during a massive hemorrhage situation, their use together, has a synergistic effect which can drastically improve survival rates in traumatically injured patients.
Conclusion
The rapid access to blood products has proven to be a major survival factor of patients with traumatic blood loss. Massive Transfusion Protocol is a vital component of this process and ensures facilities have a pre-determined and standardized approach. Medical teams should ensure that all team members are aware of such procedures and given adequate time and resources for rehearsal and training.
