Paeds SAQs · acute-care-resuscitation-and-toxicology
Hypovolaemic and haemorrhagic shock — formative SAQs
Two MedVellum formative short-answer questions on hypovolaemic and haemorrhagic shock in children: recognising compensated shock before hypotension, the bleeding-versus-non-bleeding fluid fork, balanced crystalloid aliquots for dehydration, the massive transfusion protocol, tranexamic acid dosing and timing, the lethal triad and damage control resuscitation, and early escalation to surgery and retrieval. The marks and timing support transparent self-assessment. They are not an official board format or pass standard.
On this page & tools
Target exams
SAQ 1 — A dehydrated toddler in shock
Question 1 — 10 formative marks; suggested time 15 minutes [2]
A two-year-old presents with three days of vomiting and profuse watery diarrhoea. From the doorway the child is limp and barely responsive, with sunken eyes, a weak cry, marked recession, cool mottled limbs, a heart rate of 165, a capillary refill of 5 seconds, weak central pulses and a blood pressure that is still in the low-normal range. There is no history of injury or bleeding. [2]
- State what you do in the first 60 seconds and why. (2 marks)
- Explain why a low-normal blood pressure does not exclude shock in this child. (2 marks)
- Outline your fluid resuscitation, including the fluid type, aliquot, expected response and reassessment plan. (3 marks)
- Describe how your fluid strategy would change if this child had major haemorrhage instead of dehydration, and why. (3 marks) [2]
Full-credit answer — SAQ 1
Reveal full-credit answer for SAQ 1
1. First 60 seconds
"This child is critically unwell with signs of shock: altered appearance, increased work of breathing and poor circulation to skin. I call the senior paediatric and resuscitation teams now, name a leader, allocate roles, and bring age- and weight-appropriate equipment and monitoring. I begin the hands-on ABCDE primary survey immediately and treat each threat as I find it. Stabilisation comes before diagnosis." The principle is recognise and call for help, then treat life threats as they are found. I also check bedside glucose because the child has poor intake and is unwell. [1] [2]
2. Blood pressure does not exclude shock
Children compensate for volume loss through tachycardia and vasoconstriction, so blood pressure is maintained until roughly 30 per cent of blood volume is lost. This child already shows poor perfusion: a heart rate of 165, weak central pulses, a five-second capillary refill, cool mottled limbs and altered consciousness. That is decompensated shock in evolution despite a low-normal blood pressure. Waiting for hypotension to diagnose shock is a classic and dangerous error; shock is a whole-circulation diagnosis, never a single blood-pressure number. [2]
3. Fluid resuscitation
Because there is no bleeding, this is non-haemorrhagic hypovolaemic shock, so I resuscitate with a balanced crystalloid such as Hartmann or Plasma-Lyte rather than large volumes of 0.9 per cent saline, which worsens hyperchloraemic acidosis. I give an aliquot of 10 to 20 mL per kilogram over five to twenty minutes. Before each aliquot I state the response I expect (warmer skin, shorter capillary refill, stronger pulses, improved interaction, more urine), and after each I reassess and stop for fluid overload or no benefit. The first-hour total is a ceiling, not a target. The Surviving Sepsis Campaign 2026 children's guideline supports up-front boluses with careful reassessment and attention to fluid balance. [4]
4. Change if this were haemorrhage
If the child had major haemorrhage, the first fluid would change from crystalloid to blood products. I would first control the bleeding with direct pressure, a tourniquet or a pelvic binder as appropriate, then activate the paediatric massive transfusion protocol to deliver balanced components (red cells, plasma and platelets in a ratio near one to one to one). I would give tranexamic acid if the injury was within three hours. I would keep crystalloid to the minimum needed to sustain perfusion while blood arrives, because large crystalloid volumes dilute clotting factors and worsen the lethal triad of hypothermia, acidosis and coagulopathy. The first decision in any shock is bleeding or not bleeding, because that decides the first fluid. [5] [9]
SAQ 2 — A bleeding school-age child
Question 2 — 10 formative marks; suggested time 15 minutes [5]
An eight-year-old, 25 kg child is brought to the emergency department 45 minutes after falling from a horse, with abdominal pain and distension. Heart rate is 150, blood pressure is 84/50, capillary refill is 4 seconds, the limbs are cold and mottled, and the child responds to voice but cannot sustain interaction. There is no external bleeding. The hospital has a paediatric massive transfusion protocol, surgical cover and a blood bank. [5]
- Outline the immediate resuscitation steps in the first fifteen minutes, in order. (3 marks)
- Give the paediatric tranexamic acid dose and the time window that governs its use, with the evidence. (2 marks)
- Describe the massive transfusion protocol: the trigger, the component doses and ratio, and how you prevent the lethal triad. (3 marks)
- Discuss the role of permissive hypotension in this child and how you would decide on the blood-pressure target. (2 marks) [5]
Full-credit answer — SAQ 2
Reveal full-credit answer for SAQ 2
1. Immediate resuscitation
I declare haemorrhagic shock and call the resuscitation and surgical teams, name a leader and allocate roles. I run ABCDE with cervical spine protection, give high-flow oxygen, and place two large-bore cannulae or intraosseous needles. I take point-of-care haemoglobin, lactate, coagulation, ionised calcium and glucose, and send a group and cross-match. I control external bleeding if any appears, and I apply a pelvic binder if a pelvic fracture is suspected (though concealed intra-abdominal loss is the leading concern here). I activate the massive transfusion protocol immediately rather than waiting for laboratory confirmation, and I call for critical-care and retrieval support in parallel. I reassess after every intervention. [1] [5]
2. Tranexamic acid
The child is within the three-hour window (the injury was 45 minutes ago), so I give tranexamic acid now. The paediatric dose is a loading infusion of 15 mg per kilogram (maximum one gram), followed by a maintenance infusion of 2 mg per kilogram per hour for at least eight hours (maintenance maximum one gram). For this 25 kg child that is 375 mg loading then 50 mg per hour. The CRASH-2 trial showed reduced mortality when tranexamic acid was given within three hours of injury, with the greatest benefit in the first hour; after three hours the benefit disappears and late administration may be harmful, so the timing is a hard rule. [6] [7]
3. Massive transfusion protocol
I activate the protocol because the child is in haemorrhagic shock with likely ongoing loss exceeding what crystalloid can safely replace. I request balanced components: red cells 10 to 20 mL per kilogram, plasma 10 to 20 mL per kilogram, and platelets 5 to 10 mL per kilogram, in a ratio near one to one to one, delivered in pre-packed boxes scaled to weight. I repeat cycles guided by perfusion, haemoglobin, coagulation and ionised calcium. To prevent the lethal triad I warm the child actively and warm every unit through a blood warmer, correct ionised calcium because citrate in stored blood chelates it, watch the potassium, and give targeted coagulation correction (cryoprecipitate or fibrinogen concentrate for low fibrinogen). I minimise crystalloid to avoid dilutional coagulopathy. [5] [9]
4. Permissive hypotension
In adult trauma a deliberately lower target blood pressure is used during active bleeding to reduce clot disruption before definitive control, but paediatric evidence is limited. The 2023 paediatric traumatic haemorrhagic shock consensus advises caution rather than a universal hypotensive target in children. My approach is to aim for adequate perfusion and organ preservation, accept a lower than baseline pressure only while the child is actively bleeding before definitive surgical control, and restore a normal-for-age blood pressure once bleeding is controlled. I would not apply permissive hypotension if there were any suggestion of traumatic brain injury, because the brain needs a cerebral perfusion pressure that hypotension destroys. [5]
References
- [1]Topjian, Alexa A Part 4: Pediatric Basic and Advanced Life Support 2020 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Pediatrics, 2021.PMID 33087552
- [2]Bjorklund, Ashley Pediatric Shock Review Pediatrics in review, 2023.PMID 37777656
- [4]Weiss, Scott L Surviving Sepsis Campaign International Guidelines for the Management of Sepsis and Septic Shock in Children 2026 Pediatric critical care medicine : a journal of the Society of Critical Care Medicine and the World Federation of Pediatric Intensive and Critical Care Societies, 2026.PMID 41869844
- [5]Russell, Russell T Pediatric traumatic hemorrhagic shock consensus conference recommendations The journal of trauma and acute care surgery, 2023.PMID 36245074
- [6]CRASH-2 trial collaborators 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 Lancet (London, England), 2010.PMID 20554319
- [7]Borgman, Matthew A Tranexamic acid in pediatric hemorrhagic trauma The journal of trauma and acute care surgery, 2023.PMID 36044459
- [9]Neff, Lucas P Massive Transfusion in Pediatric Patients Clinics in laboratory medicine, 2021.PMID 33494884