Bleed first, diagnose later — hypovolaemic and haemorrhagic shock

Station status

This is one MedVellum formative structured clinical encounter. The scoring, prompts and performance descriptions are educational feedback tools. They are not an official college station, timing, mark allocation, pass score or reproduced examination format. The encounter assesses first-impression recognition of haemorrhagic shock, leadership of the primary survey, bleeding control, activation of the paediatric massive transfusion protocol, tranexamic acid dosing and timing, prevention of the lethal triad, damage control resuscitation, early surgical and retrieval escalation, communication, safeguarding in parallel, and structured handover. [1] [5]

Candidate instructions

You are the paediatric registrar called to the resuscitation bay. Assess the child from the doorway and say aloud what you see. Lead a hands-on ABCDE primary survey with cervical spine protection and treat each problem as you find it. Decide early whether the child is bleeding. Speak directly to the child and parent. Reassess from A after every action. Activate the massive transfusion protocol on physiological and mechanistic grounds. Call senior, surgical, critical-care or retrieval support early. Run safeguarding alongside urgent care. Finish with a structured handover and disposition plan. Say what you would assess or do; do not perform painful or distressing manoeuvres on the actor. [5]

Room setup and observable starting state

The encounter. Mia is eight and is brought in by ambulance on a spinal board after a motor vehicle collision. She is pale, lying still, opens her eyes briefly to voice, has marked recession, and her limbs are cool and mottled. The abdomen looks distended. These are abnormalities in appearance, work of breathing and circulation to skin that signal haemorrhagic shock with concealed intra-abdominal loss. The candidate should describe these signs objectively, declare concern, call for help and begin the hands-on ABCDE primary survey with the bleeding-versus-non-bleeding fork in mind, rather than wait for imaging. [2] [5]

Simulation safety. Mia remains on the trolley and is never forcibly positioned or made to hyperventilate. Cards or the assessor supply recession, breathing sounds, monitor readings and examination findings. The parent does not obstruct urgent care. [1]

Actor cues

Parent actor

• Begin with "She was hit by a car and she's not talking to me." If asked what has changed, answer: "She's usually chatty and full of energy. Since the crash she's gone quiet, her skin feels cold, and her tummy hurts when the paramedic touched it."
• Remain anxious but do not obstruct urgent care; respond to communication with relief when the candidate explains the plan clearly. [5]

Child actor

• Respond briefly to voice early in the encounter; become drowsier and harder to rouse as the scenario progresses, following the assessor's cue card.
• Do not volunteer the abdominal tendency; report "my tummy hurts" only when directly examined. [5]

Assessor cues and clinical data

Release findings as the candidate reaches each step. Reward early bleeding-control and blood-product decisions and penalise crystalloid-only resuscitation and delayed protocol activation. [5]

A and B - Airway and breathing

Airway is patent but the voice is weak; no stridor. Cervical spine is immobilised. On high-flow oxygen the saturation is 96 per cent with a reliable waveform and good air entry. Expected strong behaviour: protect the airway and cervical spine, give high-flow oxygen, judge effectiveness by air entry and interaction, and note that the respiratory picture does not explain the shock, which points to a circulatory cause. [1]

C - Circulation

Heart rate 150, weak central pulses, capillary refill 4 seconds, blood pressure 84/50, cool mottled limbs, abdomen tender and distended. Expected strong behaviour: diagnose haemorrhagic shock from the whole picture, do not wait for hypotension to worsen; place two large-bore cannulae or intraosseous access; take point-of-care haemoglobin, lactate, coagulation, ionised calcium and glucose; activate the massive transfusion protocol now rather than waiting for labs; request balanced blood products in a ratio near one to one to one; keep crystalloid minimal; call surgery and critical care in parallel. [5] [9]

Bleeding control and tranexamic acid

The injury was 45 minutes ago. Expected strong behaviour: because the child is within the three-hour window, give tranexamic acid at the paediatric dose of 15 mg per kilogram loading (maximum one gram) then 2 mg per kilogram per hour for at least eight hours (maintenance maximum one gram), and state that benefit is greatest in the first hour and that the drug is avoided beyond three hours. If external bleeding appears, control it with direct pressure or a windlass tourniquet; if pelvic fracture is suggested, apply a pelvic binder. [6] [5]

The lethal triad event

During transfusion the core temperature is 34.8 degrees, ionised calcium is low, and the international normalised ratio rises to 1.9. Expected strong behaviour: recognise the lethal triad of hypothermia, acidosis and coagulopathy; warm the child actively and warm all products through a blood warmer; correct ionised calcium; give targeted coagulation correction (cryoprecipitate or fibrinogen concentrate); watch potassium; minimise chloride-rich crystalloid. State that each limb worsens the others and must be corrected in parallel, not after bleeding stops. [5] [9]

Weight and dosing

The candidate must obtain a working weight (Mia is 27 kg). Expected strong behaviour: use a measured weight if available immediately; otherwise document a working weight with its source and use the local paediatric cognitive aid for all transfusion and tranexamic acid calculations, re-weighing at the first safe opportunity. [5]

Marking domains

Debrief prompts

• What was the failing system at each stage, and what did you expect each action to change?
• Why is shock a perfusion problem rather than a blood-pressure problem, and how did the first impression help you act before the pressure fell?
• How did the bleeding-versus-non-bleeding fork shape your first fluid, and what would you have done differently if this had been dehydration rather than haemorrhage?
• What is the lethal triad, and how did your damage control resuscitation break each limb of it?
• How did tranexamic acid timing and dose reflect the CRASH-2 evidence, and what would you have done if the child had arrived four hours after injury?
• What structured handover content did the surgical and retrieval teams need, and how did you safeguard the child and support the family throughout? [5] [9]