Can Sustained Inflation Improve Epinephrine Absorption During Neonatal Resuscitation?

6 days ago
3 min read

One of the most rewarding parts of research isn't proving yourself right.

It's asking the next important question.

That is exactly how this study came to life.

It started with one presentation...

Earlier this year, our team published the first study comparing endotracheal tube (ETT) and supraglottic airway (SGA )administration of epinephrine in a neonatal piglet model.

We wanted to answer a simple but important question:

If vascular access is not yet available during neonatal resuscitation, could a supraglottic airway become an effective route for delivering epinephrine?

The results were intriguing.

Although plasma epinephrine concentrations were similar between the different airway routes, endotracheal administration produced a much stronger cardiovascular response than supraglottic delivery.

Like many good studies, it answered one question—but immediately created another.

One question changed everything

While presenting these results at an international meeting, Professor Gianluca Lista asked a fascinating question.

"If you delivered a sustained inflation immediately after epinephrine, wouldn't it push the medication deeper into the lungs and improve absorption?"

It was a brilliant physiological hypothesis.

A sustained inflation could potentially:

distribute epinephrine more evenly throughout the lungs,
increase contact with the alveoli,
improve pulmonary absorption,
and ultimately produce a stronger cardiovascular response.

It made perfect sense.

So we decided to test it.

Putting physiology to the test

In our new study, newborn piglets received epinephrine through either:

an endotracheal tube,
a supraglottic airway,
or the same routes immediately followed by a 20-second sustained inflation.

We carefully measured:

plasma epinephrine concentrations,
heart rate,
blood pressure,
carotid blood flow,
and other markers of cardiovascular function over the first ten minutes after administration.

If sustained inflation truly improved pulmonary drug delivery, we expected to see faster absorption and stronger physiological effects.

The answer surprised us

It didn't.

Adding a sustained inflation did not improve epinephrine absorption.

It also failed to improve:

heart rate,
blood pressure,
carotid blood flow,
or any of the major pharmacodynamic responses.

In fact, endotracheal administration alone remained the most effective airway route, while supraglottic administration continued to produce lower and delayed plasma concentrations and weaker cardiovascular responses.

Sometimes, the most important scientific finding is that a logical intervention simply doesn't work.

Why negative studies matter

Science often celebrates positive results. / But negative studies are just as valuable.

They prevent clinicians and researchers from pursuing ineffective strategies, refine our understanding of physiology, and help focus future research on ideas that truly have the potential to improve patient care.

This study tells us that simply increasing airway pressure with a sustained inflation is not enough to enhance pulmonary absorption of epinephrine.

That insight moves the field forward.

Where do we go from here?

The search for better drug delivery during neonatal resuscitation is far from over.

Future research may explore:

different epinephrine doses,
alternative drug formulations,
aerosolized or nebulized delivery,
improved supraglottic airway designs,
or entirely new vasopressor strategies.

Every experiment brings us one step closer to understanding how to deliver life-saving medications more effectively during the most critical moments of a newborn's life.

Sometimes progress comes from confirming a hypothesis.

Sometimes it comes from disproving one.

Both move science forward.

Reference

Zhou M, Liu J-Q, Ramsie M, et al. Effect of sustained inflation on pharmacokinetics and pharmacodynamics of endotracheal and supraglottic airway epinephrine in a neonatal piglet model. Pediatric Research (2026).

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