This post is a bit of a catch up, to mention articles that are worth reading, but which I didn’t have time to write a full post about, in particular studies that could have a positive impact on clinical care.
Let’s stop monitoring gastric residual volumes… please!
Measuring how much liquid is left in the infant’s stomach, just before the next feed, is a practice based on good intentions, but no evidence. Good-intention-based-medicine has, unfortunately, often been proved ineffective, or even harmful, especially when compared to evidence based medicine. This study from Israel (Riskin A, et al. The Impact of Routine Evaluation of Gastric Residual Volumes on the Time to Achieve Full Enteral Feeding in Preterm Infants. The Journal of pediatrics. 2017;189:128-34). showed the same as other studies, that the only clinically detectable impact of measuring gastric residuals is to slow down how fast babies are progressed to full feeds, without any clinical benefit.
If you give babies more nutrition, they grow more.
One of many studies that show that being more “aggressive” in early nutrition has positive impacts on weight growth, but also head circumference growth, and, perhaps, long term body composition.
Genoni G, et al. Nonrandomised interventional study showed that early aggressive nutrition was effective in reducing postnatal growth restriction in preterm infants. Acta Paediatr. 2017;106(10):1589-95. Approaching recommended standards for nutritional intakes improves usual measures of postnatal growth restriction, which are based mostly on weight.
The word “aggressive” bugs me here, the idea that trying hard to approach an intra-uterine delivery of nutrients, and approximate intra-uterine growth is somehow “aggressive” strikes me as wrong-headed. If we are to reduce the obvious negative impacts of being born far too soon, we must ensure that corporal and cerebral growth approaches normal values; not just in terms of quantity, but also quality. You can certainly have quantity without quality, but can you have adequate good growth, without enough overall weight gain?
If they grow more, are they smarter?
The next study addresses some of the same issues: Raghuram K, et al. Head Growth Trajectory and Neurodevelopmental Outcomes in Preterm Neonates. Pediatrics. 2017. Infants who had better head growth in the neonatal and the post-discharge follow up period had better developmental outcomes, Infants with poorer head growth in the neonatal period, up to discharge, were affected (i.e. had poorer developmental outcomes), and their head growth correlated with their body weight increase.
I think the first barrier to overcome is to ensure that weight, head, and length growth are close to normal intra-uterine values, then we need to evaluate what that means for details of body composition and developmental outcomes. I will come back to this issue soon!
At last, something better than amphotericin B?
This planned phase 3 study was stopped early because of inadequate numbers. Which is a great shame as we really needed to know if there was something better than AmphoB, which there probably is. In this study, micafungin was as effective as Amhpotericin B, and did not have more adverse events. Benjamin DK, Jr., et al. A Phase 3 Study of Micafungin Versus Amphotericin B Deoxycholate in Infants with Invasive Candidiasis. Pediatr Infect Dis J. 2018.
I have often seen minor adverse effects of Ampho B, and doses are often limited because of the concern about adverse events, most AE’s are minor, but a safer, equally effective antifungal would be a great addition. The echinocandin group, including micafungin, seem to be good candidates, with known pharmacokinetics, and a good safety profile. This phase 3 comparative trial showed little difference in efficacy or safety, but was underpowered for both, with only 30 babies in total (2:1 micafungin:amphotericin). Hats off to Danny Benjamin for trying to get this done, but a great problem in our community that we cannot do adequately powered trials to answer important question like this.
Thank you, Thank you for highlighting the gastric residue ‘thing’, I am constantly trying to stop our staff from relying on aspirates as a marker of feed intolerance, – there are SO many papers which don’t show it usefulness but just hindrance to reaching full feeds……
I will be sharing this post far and wide…….
I have worked in a unit which never measured residuals, with faster feeding and no more intestinal distress than other units. I have also worked in a unit which switched from routine measurement of residuals to a policy of never measuring residuals, with the expected result: fewer interruptions of feeds, and no impact on NEC, but shorter TPN.
Hope you are successful!
I’m skeptical about the thought that there are an abundance of studies regarding the impact of residuals on time to full feeds in infants. There are only 2 that I know of in babies, Torazza’s RCT in 2015 and this Riskin study. Torazza’s study shows a trend towards statistical significance in terms of increasing time to full feeds as a result of the practice of routine residual measurement, but NOT statistical significance. The Riskin study is pretty damning, however.
I’m actually struck by the paucity of overall evidence for the use of residuals for determining feeding intolerance, NEC, or SIP compared to how common this practice is in Neonatology units throughout the world. The evidence as you both say, does show that residuals are pretty useless.
In our unit, we have not been able to convince our staff of the lack of usefulness of residuals. We have, however, been able to convince our RNs to only report residuals to the Doctors when they are 50% of the previous feed, rather than the 20% that they were reporting prior. If they are <50%, the RNs can just re-feed. Interestingly, our time to full feeds seems to have decreased. Sarah, this may be a useful intervention for "weaning" your unit from the concept of routine measurement of residuals. Bravo Keith!
There is a review from 2014 of the literature surrounding the practice, Li YF, et al. Gastric residual evaluation in preterm neonates: a useful monitoring technique or a hindrance? Pediatr Neonatol. 2014;55(5):335-40 https://www.ncbi.nlm.nih.gov/pubmed/25129325. Which comes to a sort of null conclusion, that we have no evidence one way or the other, the studies you mention were published after that review, and I think the preponderance of the poor quality evidence we have is that routinely measuring and reacting to gastric residuals is more harmful than helpful.
I do have a question…..what gestational age is this article talking about? What ages were used in the study? I can’t imagine how huge our little 23-25 weekers bellies would be with not checking residuals and how much aspiration we would possibly have. Thanks, Peggy
The study doesn’t actually say how many of the most immature babies were included; I have worked in one unit which had not checked a residual in 20 years, including the most immature babies, and another where residuals were checked religiously (I use that adjectve advisedly). The only difference that was evident was that it took longer to reach full feeds in the second NICU, with no apparent benefit.
In my current NICU we changed from a policy of routine residual volume checks, to no checks at all with the change in feeding protocol. This included all the most immature babies as well as the more mature ones. The nurses are expected to (and do) evaluate feeding tolerance, using their clinical skills to evaluate abdominal distension and tenderness, and regurgitation frequency, but without measuring the volume (or colour) of residuals.
This led to better nutritional outcomes, with no increase in complications. So you can decrease the frequent interruption of feeds (which often occurred at night when the resident was called and stopped feeds for an increase in residual volumes), that is stimulated by an increase in measured volume of residuals, even in the most immature babies, without risk.