“Ad-Libbing” In the NICU: Cue-Based and Infant-Driven Feeding Methods

Jae Kim, MD, PhD / May 2019


The more I speak around the country, the more I become smitten with the immediacy of the moment, and veer away from my slides and script to interject a pearl or observation that comes to mind, or to reflect what I think the audience needs to hear at that time. That introduces a spontaneity that keeps me and the audience fresh and spiriting a live moment. Ad libbing those moments are outwardly complex events, but doing it more often makes them more subconscious and intuitive.

This is also true when we eat. We don’t tell all our 50 muscles that are responsible for swallowing food to act in a concerted way without impairing our ability to breathe effectively and safely. If you own a pet you will see that they will sleep when they feel like it, stretch and stroll when the demand comes, and eat whenever they need. They follow their urges. Although as adults we lean towards eating scheduled two to three meals per day with some snacking in between, each meal is calibrated based on our immediate hunger or urge (actually, there is evidence that the size of our plates can alter our intake (!) so I may not be completely accurate here).

For preterm infants, gastric tube feeding results in the override of instincts, and plants a fixed amount of feeding into their stomachs. When oral feeds are being established, we have a choice to determine when these feeds will be adjustable based on hunger cues. Most algorithms are very structured until the very end when they release the infant to follow their urges, go “ad lib,” and feed more intuitively and naturally. The growing trend toward cue-based or infant-driven feeding is now well established. Feeding preterm infants by schedule is an artificial construct that we imposed for initiation of safe feeding to these vulnerable infants, but needs to transition to natural urge feeding as soon as possible. The problem is that there is still debate on how and when that can take place.

The challenges with demand feeding in a hospitalized setting like the NICU is that nursing becomes challenged with an imprecise pattern of feeding. The ability to feed three infants on a 3:1 assignment who are all on the spectrum of oral feeding progression is no small feat. This balancing act is a wonder to witness as some seasoned nurses can juggle the cares, warm the feedings, and oral feed train their charges with such poise. The urge to simply put a feeding down the enteral tube and move onto the next baby is hard to resist. These heavy assignments really need to be considered in the larger context of what is best for feeding infants.

I have long been suspicious that we were not quite there with infant feeding when infants were taken off our structured protocols and then put on ad lib feeding varying time and volume for the feedings. A good number of these infants would expand their feeding repertoire immediately, and drastically varying the timing of their feeding and their volumes, often jumping by more than 20-30% from their previous feeding goals. Recently our NICU, under the expert guidance of our awesome occupational therapists (OT) team, Erika Clemens and Cindy Ritter, crafted an new cue-based feeding algorithm called “Wee Feeds” that combines the evidence out there in gradually allowing an infant to pick up their skills at oral feeding, and coordinate all those muscles to make an efficient swallow occur. Only when this is patterned and robust, permit a charge towards ad lib feeding. This new algorithm has ad lib feeds introduced much earlier in the feeding timeline than ever before for us. We have been wonderfully pleased with the success of the algorithm so far in as much as the bedside appreciation of the intuitiveness of the feeding approach, as it really helps set the stage for most of our infants in becoming proficient before voluminous and frequent feeding is upon them. We will be analyzing our data shortly, and plan to share those results in the near future.

I have had a longstanding beef that how we manage feeding is imprecise, and that the OTs in our unit can offer much more richness to our feeding practices. For instance, when I perform rounds in our NICU, I will ask how the night went. The housestaff will tell me that oral feeding did not go well overnight. Okay, I say, how bad was it? Then a pause follows as further details were not gleaned. I turn to the bedside nurse and ask the same question. Suddenly details follow that color the night events. The baby wanted to feed, but once they got started they lost interest and fell asleep. They were stimulated to wake up, took a few mLs more, and then spit up a bit right after. The feeding was continued a bit longer and then the infant started turning away from the nipple. When the baby was placed back on the bed after the short feeding, the infant proceeded to throw up all of the feed that they took for the protracted 20 minute feeding. “Well, details do matter in oral feeding,” I say to the housestaff. I tell them to use the EATTMOR mnemonic (something our SPIN team came up with) to help characterize feeding in the most colorful way. What went well or wrong: Energy, Aversion, Tone, Tempo, Maturity, Oromotor coordination, and/or Reflux. These features matter because they tell us what the feeding experience looked like and what we may need to prescribe for next actions, sometimes polar opposites of each other. A baby who is refluxing is different from a baby who is simply too young and not cueing well, who is different from one who can’t pace (tempo) their feeding well.

Earlier and more efficient feeding through quality improvement cue-based feeding programs may have positive effects not only on feeding outcomes but also on length of stay.1 Exciting recent attempts to provide oromotor training with non-nutritive sucking with specific devices appear to speed up the oral feeding timeline to full feeds and reduce length of stay.2 Of course, then, the opposite is true too. Poor or slow feeding may be associated with a whole slew of negative outcomes. Over-aggressive feeding can lead to poor regressive feeding behavior, the most serious being feeding aversion. Our preterm infant graduates keep toddler feeding clinics alive. I still don’t know from the literature if it is better to orally feed frequent partials or limit to successful full oral feeds before advancing, although I am tending now towards the latter. When to pull the trigger on “ad libbing” is still unclear, or whether to limit volume or limit time intervals first is not clear.

I wrote a comment in the past that we are all baby whisperers because we get good at understanding the cues of our infants. This is never more true than to know that cry is for food or that the movements, stare, or stretch of the neck are not so subtle signals of a speechless infant wanting to have their milk, now! Next time you want to feed a baby, listen to the whispers and then let them ad lib it!

Suggestions to go

  1. Develop and implement an infant-driven or cue-based feeding protocol
  2. Talk the OT talk, describe feedings in detail, think EATTMOR
  3. Staff accordingly for the baby’s and nurse’s sake. Infants undergoing oral feeding require significantly more attention to properly and safely feed them
  4. Never overfeed please. Think water boarding…
  5. Respect reflux.



  1. Fry TJ, Marfurt S, Wengier S. Systematic Review of Quality Improvement Initiatives Related to Cue-Based Feeding in Preterm Infants. Nurs Womens Health. 2018 Oct;22(5):401-410. doi: 10.1016/j.nwh.2018.07.006. Epub 2018 Aug 21. Review. PubMed PMID: 30138603.
  1. Song D, Jegatheesan P, Nafday S, Ahmad KA, Nedrelow J, Wearden M, Nemerofsky S, Pooley S, Thompson D, Vail D, Cornejo T, Cohen Z, Govindaswami B. Patterned frequency-modulated oral stimulation in preterm infants: A multicenter randomized controlled trial. PLoS One. 2019 Feb 28;14(2):e0212675. doi: 10.1371/journal.pone.0212675. eCollection 2019. PubMed PMID: 30817764; PubMed Central PMCID: PMC6394921.


About the Author

Jae Kim is an academic neonatologist and pediatric gastroenterologist and nutritionist at UC San Diego Medical Center and Rady Children’s Hospital of San Diego. He has been practicing medicine for over 23 years both in Canada and the USA. He has published numerous journal articles, book chapters, and speaks nationally on a variety of neonatal topics. He is the Director for the Neonatal-Perinatal Medicine Fellowship Program at UC San Diego and the Nutrition Director of an innovative multidisciplinary program to advance premature infant nutrition called SPIN (Supporting Premature Infant Nutrition, spinprogram.ucsd.edu). He is the co-author of the book, Best Medicine: Human Milk in the NICU. Dr. Kim is a clinical consultant with Medela LLC.