The verdict is in! Feed faster or slower if born at

The verdict is in! Feed faster or slower if born at <32 weeks & <1500g?

I presented this topic as a fellow many years ago after a paper came on the scene suggesting better outcomes with a faster approach. The paper Randomized trial of “slow” versus “fast” feed advancements on the incidence of necrotizing enterocolitis in very low birth weight infants. was plagued by the same issue as others created around those years which was a small number of patients at the lowest gestational ages. Any differences in sub analyses were difficult to really believe as the outcomes could have easily been explained by chance. Having said that, many centres began advancing feeds a little faster than the typical 20 ml/kg/d in favour of 30 ml/kg/d. It would take some time to coordinate a trial large enough to really answer questions about relevant issues such as time to developmental outcomes, time to full feedings and rates of NEC and the time appears to be now.

The SIFT trial

This trial was the result of a great deal of coordination between 55 different centres. For inclusion, infants had to be <1500g and <32 weeks gestational age at birth. Once the decision was made to advance feeds, babies were randomized to receive increases of 18 mL/kg/d vs 30 ml/kg/d. The primary outcome was survival without mod-erate or severe neurodevelopmental disability at 24 months CGA. What is striking about the study is its size. The number of babies in the fast arm was 1394 while 1399 in the slower group. In terms of having sufficient numbers of infants who were at the earliest gestational ages they were able to accomplish this as shown in this table.

Importantly when looking at the primary outcome 87.4% of infants in the faster group vs 88.7% in the slower group were followed up for assessment. It is also worth mentioning that this is even more impressive in terms of retention when one considers that about 6% in both arms died before assessment.

What were the findings then?

There was no difference in the primary outcome or for that matter each of its’ competing parts.

The authors in a secondary analysis did show a very marginal significant finding favouring slow feeds with respect to motor outcome. I concur with the authors though that given the small effect size and the “fishing” for results this likely is simply a chance finding. I can’t think of any reason why that would be the case either from a biological standpoint.

Not surprisingly another significant finding was shorter durations to reach full feeds (10 vs 7 days) and days on TPN at 11 vs 9 in the slow vs fast groups. In spite of having less need for central venous access, the authors were unable to show a reductoin in late onset sepsis or NEC.

Does it change your management?

I suppose that depends on what your management currently is. If you are like our centre and already advancing feedings by 30 ml/kg/d then I suspect not much. If you are in a slow centre one can take away from this study that at the very least you can lessen your patient’s need for central venous access and TPN. Based on this study and my suspicion that there will be no bigger trial forthcoming, whatever you decide to do this is about the best data that you will be getting.

The verdict is in! Feed faster or slower if born at

Can Human Milk Oligosaccharides Prevent NEC?

Any regular reader of this blog will know that human milk and the benefits derived from its consumption is a frequent topic covered. As the evidence continues to mount it is becoming fairly clear that the greater the consumption of mother’s own milk the better the outcomes appear to be with respect to risks of late onset sepsis or BPD as examples. Moving to an exclusive human milk diet has been advocated by some as being the next step in improving outcomes further. While evidence continues to come suggesting that replacement of fortification with a human based instead of a bovine based fortifier may improve outcomes, the largest studies have been retrospective in nature and therefore prone to the usual error that such papers may have.

What is evident though as the science pursues this topic further is that the risk of necrotizing enterocolitis or NEC is not zero even with a human milk diet. Why is that? It might be that some risks for NEC such as intestinal ischemia or extreme prematurity simply are too much to overcome the protective effect of breastmilk. Perhaps though it could be related to something intrinsic in the breastmilk that differs from one mother to another with some producing more protective milk than others.

Secretors vs Non-secretors

When it comes to the constituents of breastmilk, human milk oligosaccharides or HMOs are known to be secreted into breastmilk differently depending on whether a mother has a secretor gene or not. this has been demonstrated recently in HMOs affecting the microbiome in infants Association of Maternal Secretor Status and Human Milk Oligosaccharides With Milk Microbiota: An Observational Pilot Study. HMOs are capable of a few things such as stimulating growth of beneficial microbes and acting as “receptor decoys” for pathogenic bacteria. Previous rat models have also demonstrated their potential to reduce NEC in rat models. Essentially, mothers who have the secretor gene produce more diverse types of HMOs than mothers who are secretor negative.

The Type of HMO May Be the Key To Reducing NEC Wejryd E et al in 2018 published Low Diversity of Human Milk Oligosaccharides is Associated with Necrotising Enterocolitis in Extremely Low Birth Weight Infants This paper was an offshoot of the PROPEL study on the use of prophylactic probiotcs to reduce severe morbidities. Babies were all born between 23 + 0 to 27 +6 weeks and all infants received exclusive breastmilk. All fortification was with a bovine product. Breastmilk samples were obtained from 91 mothers of 106 infants at 2 weeks, 28 days after birth and finally at 36 weeks PMA and the HMO content analyzed.

What came out of the study were a couple very interesting findings. The first is that when analyzing the HMOs present in breastmilk at 2 weeks and comparing those who developed NEC to those who did not there was one significant difference. Lacto-N-difucohexaose I (LNDH I) had a median level of 0 (IQR 0-213) from the milk of those mothers who had infants affected by NEC. There were no differences observed for any other HMOs.

Also of interest was the greater diversity of HMOs present in the breastmilk samples of mothers whose infants did not develop NEC. This was present at all time points.

How Could This Be Useful?

If a broader array of HMOs is associated with less risk of NEC and the presence of LNDH I carries the same association it opens the door to the next phase of this research. Could provision of LNDH I in particular but moreover a wide array of HMOs to mother’s milk reduce the occurrence of NEC? This will need to be tested of course in well designed randomized trials but this type of fortification could be the next step in what we add to human milk to enhance infant outcomes. Given that it may be difficult to determine in short order whether women have these HMOs already a broad based fortification strategy assuming insufficient amounts of HMOs would be best. A quick search on clinicaltrials.gov shows that there are 101 trials in children looking at HMOs at the moment so more information on this topic is certainly on the way. Could HMOs be the magic bullet to help reduce NEC? Just maybe!

Keeping up with the Kardashians: Should you eat your placenta after delivery?

Keeping up with the Kardashians: Should you eat your placenta after delivery?

The medical term for this is placentophagy and it is a real thing. If you follow the lay press you may have seen that originally this was promoted by Kourtney Kardashian who did this herself and then by Kim who planned on doing the same after delivery. See Did Kourtney Kardashian Eat Her Placenta?

This is not completely without basis as many readers will be thinking already that they have heard about the health benefits of doing the same. Reports of improved mood and reductions in the baby blues following ingestion of placenta as well as improvements in breast milk production have led to this growing practice. The evidence for this up until recently though was quite old and fraught with poorly design of such studies. The bigger driver however has been word of mouth as many women having heard about the promises of better mood at the very least have thought “why not? Can’t hurt.”

What I will do in this post is run through a little background and a few recent studies that have shed some light on how likely this is to actually work.

Where did the idea come from?

Animals eat their placentas after delivery. It turns out that unprocessed placenta is quite high in the hormone prolactin which is instrumental for breastfeeding. Given the large amount of this hormone as well as the number of other hormones present in such tissue it was thought that the same benefits would be found in humans. Eating unprocessed human tissue whether it is put in a capsule or not is unwise as unwanted bacteria can be consumed. In fact, a case of GBS sepsis has been linked to such a practice in which the source of the GBS was thought to be due to contaminated unprocessed maternal placenta that had been ingested. Buser GL, Mat´o S, Zhang AY, Metcalf BJ, Beall B, Thomas AR. Notes from the field: Late-onset infant group B streptococcus infection associated
with maternal consumption of capsules containing dehydrated placenta.

What happens when you process placenta by steaming and drying?

This would be the most common way of getting it into capsules. This process which renders it safe to consume may have significant effects on reducing hormonal levels.This was found in a recent study that measured oxytocin and human placental lactogen (both involved positively in lactation) and found reductions in both of 99.5% and 89.2%, respectively compared versus raw placenta. I would assume that other hormones would be similarly affected so how much prolactin might actually wind up in these capsules after all?

Clinical Randomized Double Blind Controlled Trial

Twenty seven women from Las Vegas were recruited into a pilot trial (12 beef placebo vs 15 steamed and dried placenta) with the authors examining three different outcomes across three studies. The first study Effects of placentophagy on maternal salivary hormones: A pilot trial, part 1 looked at a large number of salivary hormones at four time points. Plasma samples were taken as well to determine the volume of distribution of the same. First samples were at week 36 of gestation then within 4 days (96 h) of birth followed by days 5–7 (120–168 h) postpartum and finally Days 21–27 (504–648 h) postpartum. All consumption of capsules was done in the home as was collection of samples. As per the authors in terms of consumption it was as follows “two 550 mg capsules three times daily for the first 4 days; two 550 mg capsules twice daily on days 5 through 12, and then to decrease the dose to two 550 mg capsules once daily for the remainder of the study (days 13 through approximately day 20 of supplementation).

Outcomes

No difference was found between salivary concentrations of hormones at any time point other than that with time they declined following birth. Curiously the volume of distribution of the hormones in serum was slightly higher in the placenta capsule groups but not enough to influence the salivary concentrations. It was felt moreover that the amount of incremental hormone level found in the serum was unlikely to lead to any clinical response.

The second study was on mood Placentophagy’s effects on mood, bonding, and fatigue: A pilot trial, part 2. Overall there were no differences for the groups but they did find “some evidence of a decrease in depressive symptoms within the placenta group but not the placebo group, and reduced fatigue in placenta group participants at the end of the study compared to the placebo group.”

The last paper published from the same cohort is Ingestion of Steamed and Dehydrated Placenta Capsules Does Not Affect Postpartum Plasma Prolactin Levels or Neonatal Weight Gain: Results from a Randomized, Double-Bind, Placebo-Controlled Pilot Study. This study specifically addressed the issue of prolactin levels and found no difference between the groups. Neonatal weight gain was used as a proxy for breastmilk production as it was thought that if there was an effect on breastmilk you would see better weight gain. About 80% in both groups exclusively breastfed so the influence of formula one can’t take out of the equation. In the end weight gain was no different between groups although a trend to better weight gain was seen in the placebo group.

To eat or not to eat that is the question?

What is clear to me is that the answer to this question remains unclear! What is clear is that I don’t think it is wise to consume raw placenta due to the risks of bacterial contamination. Secondly, the levels of hormones left in the placental preparation and the most common preparation of steaming and drying leave hormone levels that are unlikely to influence much at all from a biochemical standpoint. It also seems that breastmilk production and neonatal weight gain aren’t influenced much by consumption of these pills.
The issue though in all of this is that while the previous research was of low quality, the current research while of better quality is at a low volume. These were pilot trials and not powered to find a difference likely. The finding in the subgroup of some effect on mood at the end of the study does leave some hope to those that believe in the power of the placenta to help. Would a larger study find benefit to this practice? My suspicion from a biochemical standpoint is not but that one may feel a benefit from a placebo response.
Should you go out and have your placenta prepared for consumption? If you have Kardashian like wealth then go for it if you think it will help. If you don’t then I would suggest waiting for something more definitive before spending your money on placentophagy.

It’s time to approach nutrition in extreme preemies as if it were a drug

It’s time to approach nutrition in extreme preemies as if it were a drug

One of the benefits of operating this site is that I often learn from the people reading these posts as they share their perspectives.  On a recent trip I was reunited with Boubou Halberg a Neonatologist from Sweden whom I hadn’t seen in many years.  I missed him on my last trip to Stockholm as I couldn’t make it to Karolinska  University but we managed to meet each other in the end.  As we caught up and he learned that I operated this site he passed along a paper of his that left an impact on me and I thought I would share with you.

When we think about treating an infant with a medicinal product, we often think about getting the right drug, right dose and right administration (IV, IM or oral) for maximum benefit to the patient.  When it comes to nutrition we have certainly come a long way and have come to rely on registered dietitians where I work to handle a lot of the planning when it comes to getting the right prescription for our patients.  We seem comfortable though making some assumptions when it comes to nutrition that we would never make with respect to their drug counterparts.  More on that later…

A Swedish Journey to Ponder

Westin R and colleagues (one of whom is my above acquaintance) published a seven year retrospective nutritional journey in 2017 from Stockholm entitled Improved nutrition for extremely preterm infants: A population based observational study.  After recognizing that over this seven year period they had made some significant changes to the way they approached nutrition, they chose to see what effect this had on growth of their infants from 22 0/7 to 26 6/7 weeks over this time by examining four epochs (2004-5, 2006-7, 2008-9 and 2010-11.  What were these changes?  They are summarized beautifully in the following figure.

Not included in the figure was a progressive change as well to a more aggressive position of early nutrition in the first few days of life using higher protein, fat and calories as well as changes to the type of lipid provided being initially soy based and then changing to one primarily derived from olive oil.  Protein targets in the first days to weeks climbed from the low 2s to the mid 3s in gram/kg/d while provision of lipid as an example doubled from the first epoch to the last ending with a median lipid provision in the first three days of just over 2 g/kg/d.

While figure 3 from the paper demonstrates that regardless of time period there were declines in growth across all three measurements compared to expected growth patterns, when one compares the first epoch in 2004-2005 with the last 2010-11 there were significant protective effects of the nutritional strategy in place.  The anticipated growth used as a standard was based on the Fenton growth curves.

What this tells us of course is that we have improved but still have work to do.  Some of the nutritional sources as well were donor breast milk and based on comments coming back from this years Pediatric Academic Society meeting we may need to improve how that is prepared as growth failure is being noted in babies who are receiving donated rather than fresh mother’s own milk.  I suspect there will be more on that as time goes by.

Knowing where you started is likely critical!

One advantage they have in Sweden is that they know what is actually in the breast milk they provide.  Since 1998 the babies represented in this paper have had their nutritional support directed by analyzing what is in the milk provided by an analyzer.  Knowing the caloric density and content of protein, carbohydrates and fats goes a long way to providing a nutritional prescription for individual infants.  This is very much personalized medicine and it would appear the Swedes are ahead of the curve when it comes to this.  in our units we have long assumed a caloric density of about 68 cal/100mL.  What if a mother is producing milk akin to “skim milk” while another is producing a “milkshake”.  This likely explains why some babies despite us being told they should be getting enough calories just seem to fail to thrive.  I can only speculate what the growth curves shown above would look like if we did the same study in units that actually take a best guess as to the nutritional content of the milk they provide.

This paper gives me hope that when it comes to nutrition we are indeed moving in the right direction as most units become more aggressive with time.  What we need to do though is think about nutrition no different than writing prescriptions for the drugs we use and use as much information as we can to get the dosing right for the individual patient!

Use of A Rescue Exclusive Human Milk Diets in Infants < 1250g. The Winnipeg Experience

Use of A Rescue Exclusive Human Milk Diets in Infants < 1250g. The Winnipeg Experience

Exclusive human milk (EHM) diets using either mother’s own milk or donor milk plus a human based human milk fortifier have been the subject of many papers over the last few years. Such papers have demonstrated reductions is such outcomes as NEC, length of stay, days of TPN and number of times feedings are held due to feeding intolerance to name just a few outcomes. There is little argument that a diet for a human child composed of human milk makes a great deal of sense. Although we have come to rely on bovine sources of both milk and fortifier when human milk is unavailable I am often reminded that bovine or cow’s milk is for baby cows.

Challenges with using an exclusive human milk diet.

While it makes intuitive sense to strive for an exclusive human milk diet, there are barriers to the same. Low rates of maternal breastfeeding coupled with limited or no exposure to donor breast milk programs are a clear impediment. Even if you have those first two issues minimized through excellent rates of breast milk provision, there remains the issue of whether one has access to a human based fortifier to achieve the “exclusive” human milk diet.

The “exclusive” approach is one that in the perfect world we would all strive for but in times of fiscal constraint there is no question that any and all programs will be questioned from a cost-benefit standpoint. The issue of cost has been addressed previously by Ganapathy et al in their paper Costs of Necrotizing Enterocolitis and Cost-Effectiveness of Exclusively Human Milk-Based Products in Feeding Extremely Premature Infants. The authors were able to demonstrate that choosing an exclusive human milk diet is cost effective in addition to the benefits observed clinically from such a diet. In Canada where direct costs are more difficult to visualize and a reduction in nursing staff per shift brings about the most direct savings, such an argument becomes more difficult to achieve.

Detractors from the EHM diet argue that we have been using bovine fortification from many years and the vast majority of infants regardless of gestational age have little challenge with it. Growth rates of 15-20 g/kg/d are achievable using such fortification so why would you need to treat all patients with an EHM diet?

A Rescue Approach

In our own centre we were faced with these exact questions and developed a rescue approach. The rescue was designed to identify those infants who seemed to have a clear intolerance to bovine fortifier as all of the patients we care for under 1250g receive either mother’s own or donor milk. The approach used was as follows:

A. < 27 weeks 0 days or < 1250 g
          i. 2 episode of intolerance to HMF
ii. Continue for 2 weeks

This month we published our results from using this targeted rescue approach in Winnipeg, Human Based Human Milk Fortifier as Rescue Therapy in Very Low Birth Weight Infants Demonstrating Intolerance to Bovine Based Human Milk Fortifier with Dr. Sandhu being the primary author (who wrote this as a medical student with myself and others. We are thrilled to share our experience and describe the cases we have experienced in detail in the paper. Suffice to say though that we have identified value in such an approach and have now modified our current approach based on this experience to the following protocol for using human derived human milk fortifier in our centre to the current:
A. < 27 weeks 0 days or < 1250 g
i. 1 episode of intolerance to HMF
ii. Continue for 4 weeks
B. ≥ 27 week 0 days or ≥ 750g
i. 2 episodes of intolerance to HMF
ii. Continue for 4 weeks or to 32 weeks 0 days whichever comes sooner

We believe given our current contraints, this approach will reduce the risk of NEC, feeding intolerance and ultimately length of stay while being fiscally prudent in these challenging times. Given the interest at least in Canada with what we have been doing here in Winnipeg and with the publication of our results it seemed like the right time to share this with you.  Whether this approach or one that is based on providing human based human milk fortifier to all infants <1250g is a matter of choice for each institution that chooses to use a product such as Prolacta.  In no way is this meant to be a promotional piece but rather to provide an option for those centres that would like to use such products to offer an EHM diet but for a variety of reasons have opted not to provide it to all.

The verdict is in! Feed faster or slower if born at

Is there such a thing as too much protein for preemies?

A strange title perhaps but not when you consider that both are in much need of increasing muscle mass.  Muscle takes protein to build and a global market exists in the adult world to achieve this goal.  For the preterm infant human milk fortifiers provide added protein and when the amounts remain suboptimal there are either powdered or liquid protein fortifiers that can be added to the strategy to achieve growth.  When it comes to the preterm infant we rely on nutritional science to guide us. How much is enough?  The European Society For Pediatric Gastroenterology, Hepatology and Nutrition published recommendations in 2010 based on consensus and concluded:

“We therefore recommend aiming at 4.0 to 4.5 g/kg/day protein intake for infants up to 1000 g, and 3.5 to 4.0 g/kg/day for infants from 1000 to 1800 g that will meet the needs of most preterm infants. Protein intake can be reduced towards discharge if the infant’s growth pattern allows for this. The recommended range of protein intake is therefore 3.5 to 4.5 g/kg/day.”

These recommendations are from six years ago though and are based on evidence that preceded their working group so one would hope that the evidence still supports such practice.  It may not be as concrete though as one would hope.

Let’s Jump To 2012

Miller et al published an RCT on the subject entitled Effect of increasing protein content of human milk fortifier on growth in preterm infants born at <31 wk gestation: a randomized controlled trial.  This trial is quite relevant in that it involved 92 infants (mean GA 27-28 weeks and about 1000g on average at the start), 43 of whom received a standard amount of protein 3.6 g/kg/day vs 4.2 g/kg/d in the high protein group. This was commenced once fortification was started and carried through till discharge with energy intakes and volume of feeds being the same in both groups.  The authors used a milk analyzer to ensure consistency in the total content of nutrition given the known variability in human milk nutritional content.  The results didn’t show much to write home about.  There were no differences in weight gain or any measurements but the weight at discharge was a little higher in the high protein group.  The length of stay trended towards a higher number of days in the high protein group so that may account for some of the difference.  All in all though 3.6 or 4.2 g/kg/d of protein didn’t seem to do much to enhance growth.

screenshot-2016-11-22-22-38-20

Now let’s jump to 2016

This past month Maas C et al published an interesting trial on protein supplementation entitled Effect of Increased Enteral Protein Intake on Growth in Human Milk-Fed Preterm Infants: A Randomized Clinical Trial.  This modern day study had an interesting question to answer.  How would growth compare if infants who were fed human milk were supplemented with one of three protein contents based on current recommendations.  The first group of 30 infants all < 32 weeks received standard protein intake of 3.5 g/kg/d while the second group of 30 were given an average intake of 4.1 g/kg/d.  The second group of 30 were divided though into an empiric group in which the protein content of maternal or donor milk was assumed to be a standard amount while the second 15 had their protein additive customized based on an analysis of the human milk being provided.  Whether the higher intake group was estimated or customized resulted in no difference in protein intake on average although variability between infants in actual intake was reduced. Importantly, energy intake was no different between the high and low groups so if any difference in growth was found it would presumably be related to the added protein.

Does it make a difference?

The results of this study failed to show any benefit to head circumference, length or weight between the two groups.  The authors in their discussion postulate that there is a ceiling effect when it comes to protein and I would tend to agree.  There is no question that if one removes protein from the diet an infant cannot grow as they would begin to break down muscle to survive.  At some point the minimum threshold is met and as one increases protein and energy intake desired growth rates ensue.  What this study suggests though is that there comes a point where more protein does not equal more growth.  It is possible to increase energy intakes further as well but then we run the risk of increasing adiposity in these patients.

I suppose it would be a good time to express what I am not saying!  Protein is needed for the growing preterm infant so I am not jumping on the bandwagon of suggesting that we should question the use of protein fortification.  I believe though that the “ceiling” for protein use lies somewhere between 3.5 – 4 g/kg/d of protein intake.  We don’t really know if it is at 3.5, 3.7, 3.8 or 3.9 but it likely is sitting somewhere in those numbers.  It seems reasonable to me to aim for this range but follow urea (something outside of renal failure I have personally not paid much attention to).  If the urea begins rising at a higher protein intake approaching 4 g/kg/d perhaps that is the bodies way of saying enough!

Lastly this study also raises a question in my mind about the utility of milk analyzers.  At least for protein content knowing precisely how much is in breastmilk may not be that important in the end.  Then again that raises the whole question of the accuracy of such devices but I imagine that could be the source of a post for another day.