Multisystem Trauma in Children, Part Two: Massive Transfusion, Trauma Imaging, and Resuscitative Pearls

A 5-year-old boy was playing with his older brother in front of their home when he was struck by a car. He sustained a femur fracture, splenic laceration, and blunt head trauma – the so-called Waddell’s triad.

On arrival, he was in compensated shock, with tachycardia.

He decompensates and needs blood.

How do we manage his hemodynamics and when do we perform massive transfusion? Pediatric Massive Transfusion

40 mL/kg of blood products given at any time within the first 24 hours.

Adolescents and Adult Massive Transfusion

6-8 units of packed red blood cells (PRBCs)

• Adults have about 5 L of circulating blood.
• Not including plasma, one could replace all circulating erythrocytes with about 10 units of PRBCS
• The best ratio of PRBCs:Plasma:Platelets is unknown, but consensus is 1:1:1.
• 1 unit of PRBCS is typically 300 mL of volume.

The typical initial transfusion of PRBCs in children is 10 mL/kg.

Massive transfusion in children is defined as 40 mL/kg of any blood product.

Once you start to give a child with major trauma the second 10 mL/kg dose of PRBCs – start thinking about other blood components, and ask yourself whether you should initiate your massive transfusion protocol.

The goal is to have the products ready to use in the case of the dynamic trauma patient.

The Thromboelastogram (TEG)

Direct measures the four components of clot formation. When there is endolethial damage and bleeding, the sequence that your body takes to address it is as follows:

1. Platelets migrate and form a plug
2. Clotting factors aggregate and reinforce the platelets
3. Fibrin arrives an acts like glue
4. Other cells migrate and support the clot.

R time – reaction time – the initial line in the tracing that shows time to beginning of clot formation.

• Treated with platelets

K factor – kinetics of the clot –how much the clot allows the pin to move, or the amplitude.

• Treated with cryoprecipitate

Alpha angle – the slope between the R and K measurements – reflects how quickly the fibrin glue is working.

• Treated with cryoprecipitate

Ma – maximum amplitude – reflects the overall strength of the clot.

• Treated with platelets

LY30 – the clot lysis at 30 min – is the decrease in strength of the clot’s amplitude at 30 min.

• Treated with an antifibrinolytics (tranexamic acid)

Shape Recognition

Red wine glass: a normal tracing with a normal reaction time and a normal amplitude. That patient just needs support and monitoring.

Champagne glass: a coagulopathic TEG tracing – thinned out, with less amplitude. This patient needs specific blood products.

Puffer fish or blob: a hyperfibrinolytic tracing. That patient will needs clot-stablizer.

TEG – like the FAST – can be repeated as the clinical picture changes.

The Trauma Death Spiral

Lethal triad of hypothermia, acidosis, and coagulopathy.

Keep the patient perfused and warm.

Each unit of PRBCs contains 3 g citrate, which binds ionized calcium, causing hypotension. In massive transfusion, give 20 mg/kg of calcium chloride, up to 2 g, over 15 minutes. Calcium chloride is preferred, as it is ionically readily available – just use a larger-bore IV and watch for infiltration. Calcium gluconate could be used, but it requires metabolism into a bioavailable source of calcium.

Prothrombin complex concentrate (PCC)

Prothrombin complex concentrate (PCC) is derived from pooled human plasma and contains 25-30 times the concentration of clotting factors as FFP. Four-factor PCCs contain factors II, VII, IX and X, while 3-factor PCCs contain little or no factor VII.

The typical dose of PCC is 20-50 units/kg

In the severely hemorrhaging patient – you don’t have time to wait for the other blood products to thaw – PCC is a powder that is reconstituted instantly at the bedside.

Tranexamic acid (TXA)

Tranexamic acid (TXA), is an anti-fibrinolytic agent that functions by stopping the activation of plasminogen to plasmin, and the degradation of fibrin. The Clinical Randomisation of an Antifibrinolytic in Significant Hemorrhage (CRASH-2) investigators revealed a significant decrease in death secondary to bleeding when TXA was administered early following trauma.

Based on the adult literature, one guideline is to give 15 mg/kg loading dose of TXA with a max 1 g over 10 minutes followed by 2 mg/kg/h for at least 8 h or until bleeding stops.

Resuscitative Pearls

Our goal here is damage control. Apply pressure whenever possible. Otherwise, resuscitate, identify the bleeding source, and slow or stop the bleeding with blood products or surgery.

How Children are Different in Trauma

In adults, we speak of “permissive hypotension” (also called “balanced resuscitation” or “damage control resuscitation...