A 6-year-old male is brought to your ED by local ambulance following a 5-6 metre fall from the roof of his family home. He had been trying to get his tennis ball stuck in the second-story gutter when he slipped and fell to the concrete ground below, landing on his left-hand side.
On examination, he speaks in short sentences without evidence of head injury.
His observations are P 168, BP 72/-, SaO2 99% (on O2), RR 36, and GCS 14.
Air entry is equal, but he has clinical left lower rib fractures with marked tenderness and local chest wall contusion. He is cool and clammy with a 5-6-second capillary refill time. There are no obvious long bone fractures or evidence of external haemorrhage. He has marked left upper quadrant tenderness with features of peritonism. There is a pelvic binder in situ with adequate positioning.
His initial investigations reveal gross haemoperitoneum on bedside FAST exam with a lateral compression injury to his pelvis.
As the decision is made to proceed to theatres for laparotomy, you wonder how the team should manage his volume resuscitation…
Trauma-related injuries are a leading cause of death in paediatric patients, with exsanguination accounting for ~39% of all traumatic deaths. Coagulopathy of trauma is at least as prevalent in paediatric trauma patients as in adults and carries with it increased morbidity and mortality.
Paediatric massive transfusion is a rare entity with an incidence of ~3%. This typically is associated with severe traumatic injuries plus a myriad of complications. Not surprisingly, it is predictive of higher in-hospital mortality.
What is the definition of massive transfusion?
Massive transfusion is defined as:
“the replacement (or anticipation of replacement) of greater than one circulating blood volume within the first 24 hours of resuscitation”
Studies often use cut-offs of 40 mL/kg of PRBC (over 24 hours). The common trigger for initiating massive transfusion protocols is a requirement of >40 mL/kg of PRBC (or > 20 mL/kg in 2 hours with ongoing losses anticipated).
Massive transfusion protocols (MTP) are designed to provide the right amount and balance of blood products, mimicking whole blood, to critically injured patients in order to prevent and treat haemorrhagic shock and coagulopathy. Not only does MTP guide resuscitation, but it also facilitates communication and logistical support between treating clinicians, blood bank and support staff.
MTPs are based on the recently developed concept of damage control resuscitation, which advocates for early blood component therapy (with minimisation of crystalloid use) combined with rapid surgical haemorrhage control.
Early administration of predefined, balanced ratios of RBC, FFP and PLTs has been shown to be associated with improved patient outcomes in adult trauma patients. Recently, the PROPPR trial demonstrated improved haemostasis and reduced death from exsanguination in patients receiving 1:1:1 transfusion (vs 1:1:2).
Considerations include:
Normal circulating blood volume in children is ~80 mL/kg
~90 mL/kg in infants <3 months of age
~70 mL/kg in older children (65 mL/kg in obese children)
Children have higher oxygen consumption and higher CO:blood volume ratio than adults
Clinical signs of hypovolaemia in children vary from adults due to their substantial physiologic reserve
Hypotension remains a LATE sign of shock
Narrow pulse pressure is a more sensitive marker of hypovolaemia
In addition to typical sites of blood loss (long bone fractures, peritoneal and pelvic trauma) substantial bleeding can occur in children from closed head injuries.
What are the basic principles for managing this patient?
1. Arrest external haemorrhage
- Direct compression
- Sutures or staples
- Arterial tourniquets
- Foley catheter (penetrating junctional injuries)
2. Pelvic splinting
- Low threshold for application in shocked trauma patient
- Either sheeting or proprietary product; application at the level of greater trochanters
3. Realignment of long bone fractures
4. Fluid warmers
The products
| Blood component | Approximate dosing |
|---|---|
| Cryoprecipitate | 5-10 ml/kg |
| Fresh prozen plasma | 10-20 ml/kg |
| Platelets | 10 ml/kg |
| Red blood cells | 10-20 ml/kg |
Ideally (and in non-time-critical scenarios), blood component transfusion is prescribed weight-based. Given the time pressures and urgent fashion in which these are required for the resuscitation of haemorrhage shock, many massive transfusion protocols will administer these components based on weight zones with products bundled in “packs”. The Sydney Children’s Hospitals Network delivers its products in the following “packs”.
What about the adjuncts?
Tranexamic acid
The early administration of tranexamic acid (TXA) has been associated with reduced mortality and blood product requirements in severely injured adults. Recent registry data suggest that administering TXA to severely injured children (standard adult dosing of 1 gram) is associated with decreased mortality without significant differences in thromboembolic events.
The Sydney Children’s Hospitals Network recommends a dose of 15 mg/kg over 10-15 mins
Range of 10-20 mg/kg
Maximum dose of 1g
Ideally, within 3 hours of injury
Calcium
Calcium is intimately involved in the clotting cascade and crucial for adequate inotropy and vasoconstriction. Hypocalcaemia is a common occurrence in patients requiring massive transfusion, typically due to citrate overload. It is important to regularly monitor ionised calcium and correct it accordingly.
Dose: ~0.3 mL/kg of 10% calcium gluconate.
Factor VII
In trauma patients with critical bleeding requiring massive transfusion, administration of rFVIIa has no effect on 48-hour or 30-day mortality. It is not for routine use in trauma patients.
Much of the current use of rFVIIa is for patients with critical bleeding who are unresponsive to conventional measures of surgical haemostasis and adequate component therapy. This use remains controversial, particularly because of concerns about the risk of potential thrombotic complications.
Dose: 90 μg/kg
Typically, this is guided by Haematology consultation during MTP.
The following is an example of the Children’s Hospital Westmead Massive Transfusion Protocol.
The targets are:
What are the complications of a massive transfusion?
Massive transfusion carries with it a high rate of complications. These can result from physiologic sequelae of the underlying injury or as an iatrogenic consequence of the blood products themselves.
They include, but are not limited to:
Immune
Acute haemolytic transfusion reaction: ABO-incompatibility induces intravascular haemolysis.
Febrile transfusion reaction: unexpected temperature rise (>38oC or >1oC from baseline)
Allergic Reaction (including anaphylaxis)
Transfusion-related acute lung injury: non-cardiogenic pulmonary oedema, the leading cause of transfusion-related mortality, occurs within 6 hours of transfusion.
Non-immune
Transfusion-associated circulatory overload
Transfusion-associated sepsis (bacterial contamination): 1:75,000 (PLT), 1:500,000 (pRBC); early antibiotics and haemodynamic support
Viral transmission: HIV <1 in 1 million; hepatitis C < 1 in 1 million; hepatitis B ~ 1 in 700,000
Electrolyte disturbance: hypocalcaemia, hyperkalaemia, hypomagnesaemia
Air embolism
Infection: resulting from immunomodulation
Selected references
Literature
- National Blood Authority. Patient Blood Management Guidelines: Module 1 – Critical Bleeding/Massive Transfusion. [cited April 23, 2015]. Available from: https://www.nba.gov.au
- The Sydney Children’s Hospitals Network. Massive Transfusion Protocol (MTP) – CHW Procedure. [cited April 23, 2015]
- Neff, L. P., et al. (2015). Clearly defining pediatric massive transfusion: cutting through the fog and friction with combat data. The journal of trauma and acute care surgery, 78(1), 22–8– discussion 28–9. doi:10.1097/TA.0000000000000488
- Nystrup, K. B., et al. (2015). Transfusion therapy in paediatric trauma patients: a review of the literature. Scandinavian journal of trauma, resuscitation and emergency medicine, 23(1), 21. doi:10.1186/s13049-015-0097-z
- Holcomb, J. B., et al. (2013). The prospective, observational, multicenter, major trauma transfusion (PROMMTT) study: comparative effectiveness of a time-varying treatment with competing risks. JAMA surgery, 148(2), 127–136. doi:10.1001/2013.jamasurg.387
- Holcomb, J. B., et al. (2015). Transfusion of plasma, platelets, and red blood cells in a 1:1:1 vs a 1:1:2 ratio and mortality in patients with severe trauma: the PROPPR randomized clinical trial. JAMA: the journal of the American Medical Association, 313(5), 471–482. doi:10.1001/jama.2015.12
- Livingston, M. H., Singh, S., & Merritt, N. H. (2014). Massive transfusion in paediatric and adolescent trauma patients: Incidence, patient profile, and outcomes prior to a massive transfusion protocol. Injury, 45(9), 1301–1306. doi:10.1016/j.injury. 2014.05.033
- Diab, Y. A., Wong, E. C. C., & Luban, N. L. C. (2013). Massive transfusion in children and neonates. British journal of haematology, 161(1), 15–26. doi:10.1111/bjh.12247
- Barcelona, S. L., Thompson, A. A., & Cote, C. J. (2005). Intraoperative pediatric blood transfusion therapy: a review of common issues. Part I: hematologic and physiologic differences from adults; metabolic and infectious risks. Pediatric Anesthesia, 15(9), 716–726. doi:10.1111/j.1460-9592.2004.01548.x
- Barcelona, S. L., Thompson, A. A., & Cote, C. J. (2005). Intraoperative pediatric blood transfusion therapy: a review of common issues. Part II: transfusion therapy, special considerations, and reduction of allogenic blood transfusions. Paediatric anaesthesia, 15(10), 814–830. doi:10.1111/j.1460-9592.2004.01549.x
- Eckert, M. J., et al. (2014). Tranexamic acid administration to pediatric trauma patients in a combat setting: the pediatric trauma and tranexamic acid study (PED-TRAX). The journal of trauma and acute care surgery, 77(6), 852–8– discussion 858. doi:10.1097/TA.0000000000000443
- Shakur, H., et al. (2010). Effects of tranexamic acid on death, vascular occlusive events, and blood transfusion in trauma patients with significant haemorrhage (CRASH-2): a randomised, placebo-controlled trial. The Lancet, 376(9734), 23–32. doi:10.1016/S0140-6736(10)60835-5
- Davenport, R. (2013). Pathogenesis of acute traumatic coagulopathy. Transfusion, 53 Suppl 1, 23S–27S. doi:10.1111/trf.12032
Social Media
St.Emlyn’s blog – Paediatric massive transfusion.
Emergency Medicine Education blog – Paediatric Trauma and Tranexamic Acid.[/toggle]
