Nutrition Month: The Cardiac Newborn

Nutrition and related weight gain are major issues for most of our HLHSers, and for cardiac babies in general. In recognition of Nutrition Month, we have an incredible nutrition series brought to you by Emily LaRose - dietitian at Children's Hospital Los Angeles. Emily's opening post provides a comprehensive look at several nutritional concerns and covers cardiac nutrition from birth to surgery and beyond. Thank you so much Emily for taking the time to provide our families such excellent analysis!

Emily LaRose, MS, RD, CNSC, CSP

Emily is the dietitian in the Cardiothoracic Intensive Care Unit at Children’s Hospital Los Angeles where she works with the medical team and families to provide nutrition for kiddos before and after cardiac surgery. 

Over my nearly 10 years as a registered dietitian, I have worked with children and adults of all ages.  After completing the Neonatal Nutrition Fellowship at Texas Children’s Hospital in 2006, I knew that I was destined to focus on working with infants and young kiddos.  I began in my current role in 2009 and, while I’ve seen a lot, I continue to learn from patients and families all the time.  I am part of a great medical team, and I am in regular contact with colleagues from different hospitals across the country.  Together, we can all work to understand how to help cardiac kiddos grow and thrive.

I have met so many wonderful families that serve as ongoing inspiration for the work our team does everyday.  I am honored to share some of my professional experience with the Sisters by Heart community; I hope you find it helpful.  The postings I make on this site are my own personal opinions and do not reflect the opinions or views of Children’s Hospital Los Angeles.

Since I will be covering a variety of HLHS nutrition topics over the next couple of weeks, I thought that it would make sense to divide the postings by age: the cardiac newborn, infancy into toddler-hood, growing (and sometimes picky) toddlers, and busy school age kiddos.  Happy National Nutrition Month!

The Cardiac Newborn

Usually when babies are admitted to our cardiac intensive care unit, I try to meet with parents to review how we give nutrition to these little ones before and after surgery.  With moms who may still be in the birth hospital and dads who may be shuttling back and forth between hospitals and home, it can sometimes take a little while before we’re able to speak but, all the while, we’re getting nutrition into these little ones as best as we can.

In our first visit, I review how we give nutrition to cardiac babies, and I try to make sure that moms have the support they need to get pumping if they’re planning to feed the baby breastmilk when the time comes.  Often we talk about the progression of nutrition from IV nutrition to oral feedings and everything that comes in between.  I also talk a little about my role as the dietitian on our ICU team since a lot of people aren’t familiar with what a dietitian may do when kiddos aren’t eating.

I thought for this first post I would review some of the nutrition highlights for the cardiac newborn during his or her first hospitalization.  A lot of this information comes directly from what I talk to new parents about so that they know what the nutrition plan is… and so that in the midst of everything going on with the baby, they know that we’re doing what we can to help the baby heal and grow.

The Nutrition Plan

Because blood flow to an HLHS baby’s intestines may not be stable or adequate, intravenous (IV) nutrition is often the first, and possibly only, source of nutrition for these little ones before surgery.  You may hear this called parenteral nutrition (PN) or total parenteral nutrition (TPN); you may hear the word Intralipid as well.  All of these descriptions are talking about the dextrose (sugar/carbohydrate), amino acids (protein), and fat (Intralipid) as well as vitamins, minerals, electrolytes, and other additives that can be given through a vein when feeding into a baby’s tummy isn’t possible.

We can actually get all of the nutrition that a baby needs into a tiny yellow bag and a little white syringe.  It’s not a perfect system (we’d rather feed into baby’s tummy when we can), but it’s a lifesaver- literally.

Once deemed safe, many hospitals have feeding protocols that dictate how and when to start feeding into the baby’s tummy (while the IV nutrition continues).  Most of the time, feedings are started through a small tube that is placed in the baby’s nose or mouth with a tip that sits either in the stomach or in the small intestine.

With the feeding tube in the stomach, feedings may be started continuously (given 24 hours per day) or as small volume bolus feedings every three hours or so- there is no real consensus on which way is better.  With a feeding tube in baby’s intestine, feeds are given continuously.  Eventually, these tube feedings are gradually increased (and the IV nutrition decreased) to meet the baby’s energy and protein needs.

Feeding progress is usually very slow because tummy problems can be common with HLHS.  Babies may have slowed digestion after surgery or abnormal blood flow to their intestines.  They may spit up, have bloody stools, or may be excessively fussy.  While some of these problems may be unavoidable, studies have told us that if we have a gradual feeding plan that we stick with, we can avoid some of these symptoms and make faster progress in the long run.  If we rush a baby to get more nutrition than he or she is ready for, sometimes we end up taking one step forward followed by many steps back.

So when we start feedings, what will we use?

Amy, Michelle, and Karen gave excellent perspectives on breastmilk and breastfeeding earlier this month.  Breastmilk is so amazing and provides so many immune factors, micronutrients, special fats, healthy bacteria, and other benefits to these little ones.  It is super easy to digest, and there are a number of studies out there that talk about how breastmilk can help to prevent some of the digestive problems that preemies and HLHS babies are known for.  It’s truly customized nutrition that formula will never match!

For some moms, however, providing breastmilk may not be an option.  Breast surgery, postnatal complications, certain medical conditions, some medications, and a variety of other factors may make breastfeeding difficult or impossible.  Some moms choose not to breastfeed and that is okay, too.

Using donor breastmilk (from one of the nationally recognized milk banks) can be a good option for especially sensitive infants though it is rarely used long term.    When breastmilk isn’t an option, there are plenty of formulas available for feeding infants with HLHS or for adding calories and protein to breastmilk (fortifying) when needed.

Some hospitals recommend standard formulas (like Enfamil Premium or Similac Advance) while others use semi-elemental or partially hydrolyzed formulas (like Pregestimil, Nutramigen, or Alimentum) in their feeding protocols.  In some cases, even more broken down (elemental) formulas like Elecare or Neocate are needed.  When we’re deciding which formula to use, blood flow to the baby’s belly, prematurity (and birth weight), GI problems or surgeries, and other medical conditions are all things we think about.

Are there cases where breastmilk or one of these formulas can’t be used?

As Michelle and Karen mentioned, chylothorax (or chylous effusion) can add an extra challenge when we’re talking about feeding babies with HLHS.  Chylothorax can actually happen as a result of any surgery around the heart, and treatment almost always includes diet modification.  The primary challenge is to find a way to get the long chain fat out of the baby’s diet while still getting him enough calories to grow.  Unfortunately, long chain fat is the primary fat in breastmilk and infant formula.

IV nutrition is an option and may be used in some cases though, as I’ve mentioned, we try to feed into a baby’s tummy when we can.  Skimmed breastmilk may be an option if enough fat can be removed; other formulas and special types of fat can then be added to the milk so that the infant has what she needs to grow.

If skimmed breastmilk isn’t an option, special formulas (like Enfaport, Monogen, and many others) can be used for oral or tube feedings until the drainage stops.  Treatment usually continues for another two to 10 weeks until the cardiologist is confident that the area where the leak occurred is fully healed.

When can babies start to take feedings by mouth?

As babies recover, their tube feedings will increase and the breathing tube will come out.  Once a baby is fully awake and his or her breathing is stable, we will start to think about letting the baby try some feedings by mouth- usually from a bottle.

Occupational therapists and speech language pathologists may evaluate if the baby is ready, able, and willing to take some nutrition by mouth.  They will come up with treatment plans to help the baby progress to oral feeding as long as the baby is safe to do so.  They observe babies as they eat and work with families to figure out how a baby is responding to feedings- is he sweating a lot, is her breathing rate increasing, is he working too hard, is she able to suck-swallow-breathe safely?

If a baby has a weak cry or is coughing or gagging with his feedings, swallow studies may be ordered to make sure that the breastmilk or formula isn’t going down the airway (aspiration).  In some cases, positional feeding techniques are used to prevent aspiration.  Sometimes feedings may be thickened (using baby cereal or other thickeners) if the baby is aspirating with thin liquids.  For some infants, aspiration makes feeding by mouth unsafe and long-term tube feedings are needed.

With practice, the hope is that the baby will begin to take more and more nutrition by mouth relying less on the feeding tube.  For some babies, eating causes a lot of stress so they may be limited to oral feeding a couple of times per day or for a small amount of time per feeding until they get stronger.

Once the team is confident that the baby is able to eat enough to stay hydrated, we will start talking about taking the feeding tube out.  Some babies learn to take all of their feedings by mouth within a couple of weeks and others take much longer.  Unfortunately, we don’t have great ways to predict who will eat well and who will not.  When a baby can’t eat enough by mouth, but is otherwise ready for discharge, the team may recommend that he go home with full or partial tube feedings.

So how much nutrition do cardiac babies really need?

We have all sorts of ways that we can estimate how much nutrition someone may need- from babies and toddlers to older kids and adults.  There are standard calorie levels for term babies without medical conditions as well as standards for premature babies.  All babies are different and what works for one may not work for another.  Ultimately, for HLHS babies, we rely on four things to give us hints about what a baby’s nutrition needs may be: research, previous experience, healing, and growth.

Research tells us that right after cardiac surgery babies have reduced calorie needs.  The physical stress that their little bodies go through causes their metabolism to hibernate (sort of) for a week or so.  After they recover, their nutrition needs increase, and, if they’ve been on bypass, they increase a lot.

Most research suggests that infants with HLHS often require upwards of 10 to 30% more than other term infants though there are infants who grow well on far less than we’d expect (and some who require even more).  Energy needs depend upon how well the baby is able to eat, if he or she is able to absorb the nutrition their being given, how hard he or she is working to breathe, any other medical conditions, and much more.

We think of breastmilk as having about 20 calories per ounce on average though there can be a lot of variability.  Standard formula dilution, with a few exceptions, is also 20 calories per ounce.  For our HLHS babies, we usually find that breastmilk and formula needs to be mixed to at least 24 calories per ounce for babies to grow- but not always.  Sometimes we will increase calories even further to 27 or even 30 calories per ounce to get babies to grow.

In addition to some of the formulas I’d mentioned, hind milk feedings, skimmed fat (from mom’s breastmilk), other protein, fat, and carbohydrate additives may be used to change the nutrition profile or increase the calories in breastmilk or formula.

Ultimately, the baby will tell us how much nutrition he or she needs to grow and thrive.  All babies are a little different and, like medicine, nutrition isn’t an exact science.

What is normal growth for an HLHS baby?

Weight loss just after birth is normal for all babies.  Usually, up to about 10% is expected with the goal of baby regaining his or her birth weight by two weeks of age.  But what is normal for a baby who has had surgery or who has relied on nutrition support?  It’s tough to say and can vary greatly.

Often, when we’re talking about weight gain for a newborn baby, we’re looking for about 20 to 30 grams per day (or about five to seven ounces per week) after the first two weeks of life.  We’re also expecting newborns to grow in length by 1.5 to 2.5 centimeters (1/2 to 1 inch) per month.  Again, these are general goals for all newborn babies; more weight growth may be normal for some babies, less may be normal for others, it depends.

Another consideration is to look at how proportionate a baby is using weight-for-length growth standards (charts).  If a baby is gaining weight well but is not growing longer, he may appear chubbier than other babies his age.  If a baby is gaining weight normally but is growing in length faster than most babies, she may appear thin.  Despite the average standards we use, gaining 15 grams a day may be normal for some babies while gaining 40 grams a day may be ideal for others.

If an infant is getting enough nutrition, in theory these growth goals should be possible.  Unfortunately, that still doesn’t mean that growth is easy or the same for all babies.  Getting enough nutrition to show good growth before it’s time for another surgery is vital, and I know that HLHS babies (and parents) work really hard for every ounce.

Things to think about

1. If you want to breastfeed, start pumping early on to establish your milk supply and continue pumping 8-10 times each day.  Babies usually eat every 2 to 3 hours so pumping on a similar schedule will remind your body to keep making milk even if you baby isn’t feeding just yet.  Breastmilk can be frozen for about 6 months in a regular freezer but make sure to date it so you are sure to use the older milk first.
2. Right after birth through about a week or two after surgery, a cardiac baby’s weights often do crazy things.  We see weight loss in the beginning, a lot of weight gain with fluids, weight loss again… it’s a rollercoaster!  A couple of weeks after surgery is usually a good time to start looking at what your baby’s weight is doing.  He or she may not be gaining weight by leaps and bounds, but the average trend should be positive.

3. Be patient.  Even if everything goes perfectly, it takes awhile for an HLHS baby to get to full feedings (by tube or by mouth); if we rush the process, we often have to backtrack.  Keep in mind that when babies are born, it takes time for them to learn to eat.  HLHS babies have some extra challenges including higher nutrition needs, different breathing requirements, a heart that’s working with fewer parts, digestive problems, recent surgery, etc.

4. A weight gain goal of 20 to 30 grams per day is a guideline but may not be the right amount of weight gain for all babies.  Looking at weight for length on growth charts can be a really helpful way to make sure that a baby is gaining weight proportionately over time.  Your pediatrician (or dietitian) has these growth charts if you want to see them.

5. All babies are different and it’s always okay to ask questions!  If you haven’t met a dietitian and would like to- just ask!  If you have questions about your baby’s nutrition or other medical conditions- just ask!  We’re all here to help.

Thank you, Emily! And stay tuned for next week's post in this series, Nutrition and the Cardiac Infant!