Viva 6

This is a procedure viva. The two examiners will ask you specific questions regarding the situation below. You will be asked to demonstrate as well as explain some of your answers.

As the Intensivist at a regional hospital, you are asked to the Emergency Department to assist in the resuscitation of a 10-day-old infant that has presented in a moribund state. The child was the product of a normal pregnancy, and was delivered vaginally at 38 weeks. There were no significant problems and the child was discharged at 24 hours, having initiated breast feeding. There has been a history of diarrhea and vomiting in the family for the past 5 days.

The child is grey in colour, making weak crying noises, and has a respiratory rate of 50 breaths per minute.

How would you assess this child’s circulation?

This is really a question about the assessment of the severity of hypovolemia.

(5-6% loss of body weight)
(7-10% loss of body weight)
(over 10% loss of body weight)

2 or more of:

  • Restlessness or irritability.
  • Sunken eyes (also ask the parent).
  • Thirsty and drinks eagerly.
  • Poor skin turgor; after pinch test the skin fold is visible for less than 2 seconds.

2 or more of:

  • Abnormally sleepy or lethargic.
  • Sunken eyes.
  • Drinking poorly or not at all.
  • Very poor skin turgor; after pinch test the skin fold is visible for longer than 2 seconds.
  • Weak rapid pulse
  • Cool or blue extremities
  • Hypotension
  • Rapid breathing
  • Sunken anterior fontanelle.
What would your initial management be?
(Follow up question: How would you determine the volume of resuscitation fluid required?)
  1. Assess the need for intubation.
    - At this stage, senior assistance from somebody expert in paediatric critical care is required, as the intubation may be difficult.
  2. Administer 100% oxygen.
  3. Establish venous access.
  4. Think about sedation and analgesia to support tolerance of invasive therapies
    (also decreases demands on the cardiac output)
  5. Send ABG to help electrolyte correction
  6. Fluid resuscitation:
    1. Remember normoglycaemia. According to the examiner's comments, "failure to immediately treat the hypoglycaemia was a fatal error" in Question 7 from the second paper of 2016. 
    2. Replacement of volume in dehydration:
      • Formula: Vol = % Dehydration x body weight x 10 (in mls). 
        The volume resuscitation formula given here is found in Question 7 from the second paper of 2016.
        NICE guidelines (Neilson et al, 2015) recommend isotonic crystalloid like 0.9% NaCl.
      • The college recommend ("add 100 ml of 50% dextrose to 900 ml 0.9% NaCl")
  7. Empiric antibiotics if sepsis is suspected, within 1 hour.
  8. Cultures of blood and urine.
    Consider antivirals if there is suspicion of viral meningitis or encephalitis
  9. Transfer and retrieval: The best place to care for a critically ill child is a large children's hospital with lots of experienced staff. An important plan of your plan of management will be sending your patient to such a place.
Shortly after the first attempt at venous access, the child becomes unconscious and bradycardic to a rate of 50.
What is the next most appropriate step?
  • CPR. 
  • You need not have a pulseless infant to start chest compressions; if they are bradycardic to below 60, CPR should commence.
How would you perform CPR on a child this age?
  • In all sized children, the depth of compression is one third of the AP diameter- but the technique changes: from
    • "Two finger" technique for neonates, for single rescuers
    • "Both thumbs"  technique for neonates, for trained group rescuers (the hands encircle the chest)
    • For young children, the heel of one hand may be used
  • AHA recommends about 980 compressions per minute
[optional: Can you demonstrate the chest compression technique on this mannequin?]
How will you choose the right endotracheal tube for this child?
What depth of ETT insertion do you expect?

Four formulae need to be recalled:

  • Uncuffed tube diameter: size (mm) = age (years) / 4 + 4
  • Cuffed tube diameter: size(mm) = age (years) / 4 + 3.5
  • Depth of insertion (cm) for ETT = age (years) / 2 + 12
  • Depth for a nasal tube (cm) = age (years) / 2 + 15
What instructions will you give to the airway operator, with respect to tidal volume and resp rate?
  • 30 breaths per minute. Tidal volumes are 5 to 8 mL/kg, i.e. 15 to 24 ml for this 3kg 10-day-old
  • "Coordinate chest compressions with ventilations at a ratio of 3:1 and a rate of 120 events per minute to achieve approximately 90 compressions and 30 breaths per minute" is how the AHA put it.
You have no vascular access. What are your options?
  • In infants, scalp veins are fair go.
  • The umbilical vein can be used up to 1 week after birth.
  • Intraosseous access should be established as soon as it is clear that other forms of access are going to be too fiddly or too difficult.
  • Oh's Manual recommends the use of a 10ml syringe attached to a three-way tap as the best method of achieving rapid boluses of controlled volume.
It is time for the first rhythm check. How will you choose the energy on the defibrillator?
  • Defib energy is 4J/kg, which means:
    • 12J for a 3kg neonate
    • 40J for a 10kg infant (1-yr-old)
    • 80J for a 20kg preschooler
The rhythm is PEA, rate of 80. What drugs will you ask for, and which doses?
  • Adrenaline; the dose is 10 mcg/kg, i.e. 30 mcg for a neonate.
What other assessment is necessary at this stage?
  • The trainee should run through the ABCDE algorithm again, and then address the 4Hs and 4Ts.

  •  Children typically arrest because of hypoxia or hypotension, but some mention needs to be made of:

    • the possibility of electrolyte disturbance (considering the Hx of diarrhoea)

    • the possibility of hypoglycaemia

What volume replacement boluses will you use?
  • 10ml/kg is the correct volume; i.e. 30ml per bolus in a 3kg infant
The BSL is 1.0 mmol/L. How would you correct this?
  • Glucose 50% ; the dose is 1 ml/kg.
ROSC is achieved. What essential post resuscitation care is required?
  • Transfer to a NICU/PICU 

  • This will require aeromedical retrieval

  • To get there, a paediatric ventilator will need to be organised (there may be a wait)

  • the ETT position needs to be confirmed with Xray

  • Secure venous access needs to be established 

  • Bloods need to be sent (looking for other correctable factors)

  • Family need to be conselled
  • Staff potential also need to debrief

Disclaimer: the viva stem above may be an original CICM stem, acquired from their publicly available past papers. Or, perhaps it is a slightly altered version of the original CICM stem. Or, it is a completely original viva stem, concocted by the monstrously amoral author of Deranged Physiology for nothing more than his own personal amusement. In either case, because the college do not make the main viva text or marking criteria available, almost everything here has been confabulated. It might sound like a plausible viva and it could be used for the purpose of practice, but all should be aware that it does not represent the "true" canonical CICM viva station.