The Collapsed Neonate

You're sat in the theatre coffee room debating with your esteemed colleagues whether or not direct laryngoscopy should remain the plan A of plan A, when your bleep screeches into life.

"Neonatal emergency in resus"

You neck the remainder of your coffee and jump to your feet, making eye contact with your wingman ODP who nods and heads off to grab the paediatric kit bag.

While jogging to the emergency department you start to consider the possible pathologies that might result in a neonate being brought into resus.

You arrive to a sea of chaos, with nurses, paediatricians and ED docs all clucking around a terrified mother holding a bundle of blankets with two very tiny and rather grey-looking feet poking out.

"How old?" you ask into the mayhem.

"Seven days," shouts back the ED consultant as she tries again to find a vein, "Normal delivery, term, four kilos, suddenly collapsed this morning".

What should you be considering at this stage?

This is a seven day old baby, and there is a limit to how many problems present this badly so soon after an otherwise uncomplicated birth.

The four big things to consider:

Sepsis
Cardiac
Trauma
Metabolic disease*

If you're looking at a very small, very sick baby, early antibiotics are always a good idea.

*REMEMBER GLUCOSE

You clamber round to the head end of the bay and start tearing open tiny breathing systems and facemasks with your ODP.

"What are the sats?"

"Can't get a trace," the paeds ED nurse replies, watching the blue line meandering listlessly across the angrily alarming screen, "Blood pressure won't read either."

"Has someone got a pulse?"

"Decent enough brachial," reassures the ED reg holding the arm steady for venous access, "Cool we've got a line and a gas, can someone run this please?"

What should you do with oxygen for this baby?

In the initial assessment phase, if you have any suspicion of apnoeas or respiratory failure, do not limit oxygen
Use a facemask with paediatric Mapleson C or Ayre's T piece
Provide supporting breaths if concern about apnoeas

You can worry about pulmonary hypercirculation and oxygen toxicity later, for now your main concern is preventing hypoxic brain damage.

While the blood gas is processing you gently support baby's breathing with the facemask, doing your best to reassure the mother that her baby is in the right place.

"Sats are 95% on the right arm," calls out the nurse, and you allow yourself to relax just a little.

"Have we got a fluid bolus going?"

"40 mls going in now."

"Great, and temperature?"

"36.8°C."

What are your priorities for initial cardiovascular resuscitation?

For a clearly very unwell, shocked baby with poor perfusion and pulses, prioritise the following:

IV access
IO access if more than two failed attempts at IV
5-10 ml/kg balanced crystalloid fluid bolus
Repeat up to total of 40 ml/kg if fluid-responsive*
Peripheral adrenaline boluses for profound shock despite fluid boluses
Peripheral adrenaline infusion can start at 0.1 mcg/kg/min
Early escalation to intubation and ventilation if cardiovascular or respiratory collapse
If heart rate over 200 then follow appropriate SVT/arrhythmia guideline
Consider hydrocortisone 2.5 mg/kg in refractory shock or suspected adrenal dysfunction

*Caution and reduce dose if any evidence or suspicion of heart failure.

What would make you suspect heart failure?

Cardiomegaly
Gallop rhythm
Hepatomegaly

If present, your possible diagnoses to consider include:

Congenital heart disease
Myocarditis
Cardiomyopathy

If the liver is increasing in size, stop giving fluid.

The blood gas returns

The ED registrar walks back into the bay with the familiar scrap of receipt paper you've all been waiting for.

"Here's the gas guys:

pH is 7.18
CO2 is 5
Hb is 129
Glucose is 2.6
Lactate is 9

Okay I need someone fixing glucose?"

The ED nurse nods.

How should you replace this child's blood glucose?

Start with 10% glucose bolus at 2 ml/kg
Then infusion of 4-6 mg/kg/min
Recheck at regular intervals

"Thank you, have we managed to get a blood pressure reading?"

"It's intermittent but a few minutes ago the systolic was 95."

What investigations should you be sending off?

Blood gases (arterial ideally but venous or capillary if that's all you can get)
Blood sugar
Full blood count
Coagulation screen
LFTs
Renal function
Blood culture
Request chest xray
ECG
Ammonia*

*This is essentially to answer the question of 'is this an inborn error of metabolism'?

Should you give antibiotics?

Yes, a collapsed neonate warrants broad spectrum antibiotic cover in the initial resuscitation phase.

Something very broad with viral cover such as:

Cefotaxime (50mg/kg)
Amoxicillin (60mg/kg)
High dose aciclovir

Is usually a good plan, but as always follow your institution's protocol.

Despite fluids, oxygen, antibiotics and glucose this baby doesn't seem to be getting any better, and the lactate is now 13 mmol/litre on the blood gas.

"What do we think is causing this?"

"Well he's seven days old, temperature is okay, no rashes, chest sounds clear. Do we think this might be cardiac?"

"Coarctation would explain the sats difference between the arms, and the weak femorals."

What specific features would make you think of duct dependent congenital heart disease?

Cyanosis not responding to oxygen
Femoral pulses significantly weaker than brachial
Different saturations on right arm to either leg
Heart murmur
Cardiomegaly on chest xray

Have a low threshold to start prostin, as this is the only treatment that will solve this problem, and will do relatively little harm if something else is going on.

What cardiac conditions could this be?

This could be a duct-dependent lesion, or another cardiac problem altogether.

Duct-dependent lesions

Coarctation
Interrupted aortic arch
Hypoplastic left heart syndrome
Transposition of the great arteries

Other

SVT
Myocarditis
Cardiomyopathy

You're going to need an echo to find out for sure.

You've discussed with your local paediatric intensive care team who have agreed to retrieve the child, and advise you start prostin (a.k.a. alprostadil or prostaglandin E1) in the meantime.

What dose should you start prostin at?

The following are ball-park figures to give you an idea of the sort of numbers we're talking about - you should of course follow the guidance specific to your institution.

5 nanograms/kg/minute if clinically stable
20 if absent femoral pulses
50 if severely shocked

This can be titrated up to 50-100 if response is inadequate, but this needs senior paediatric or cardiology input first.

What are the adverse effects of prostin?

Can trigger apnoea
Can cause hypotension

The ED consultant catches your eye and asks whether you think you should intubate this child.

What are the indications for intubation and ventilation in a collapsed neonate?

Evidence of persistent pre-ductal hypoxaemia
Severe respiratory distress
Apnoea
Shock
Ongoing seizures
Raised intracranial pressure

What are the indications for intubation and ventilation in this instance?

Severe persistent acidosis
Apnoeas
If you need to transfer a child and are running more than 15 nanograms/kg/minute of prostin

Prostin doses > 10-20 nanograms/kg/min are likely to cause apnoea and so you want to start thinking about intubation and ventilation.

What should you consider when intubating this child?

PEEP can help a struggling left ventricle
Likely to be unstable on induction, use ketamine rather than propofol
Have vasopressors ready - peripheral low dose adrenaline is your friend

What are the non-cardiac things to consider?

Sepsis - Group B strep, E. coli, Herpes Simplex, Pertussis
Metabolic - urea cycle defect, organic acidaemia, mitochondrial disorder
Trauma - intracranial bleed, intra-abdominal bleed

You successfully induce the child with ketamine and rocuronium, intubate smoothly without causing the child to desaturate, and stabilise them on the ventilator.

The dose of prostin is increased, and eventually the retrieval team arrive to transfer the child to the tertiary centre PICU for consideration of operative management.

The following morning, you hear back from the PICU consultant.

Echocardiography confirmed critical coarctation of the aorta, with severely impaired systemic perfusion following ductal closure, that has (for now) improved dramatically with the prostin.

Well done you.