Look around an NICU and you will see many infants living in incubators. All will eventually graduate to a bassinet or crib but the question always is when should that happen? The decision is usually left to nursing but I find myself often asking if a baby can be taken out. My motivation is fairly simple. Parents can more easily see and interact with their baby when they are out of the incubator. Removing the sense of “don’t touch” that exists for babies in the incubators might have the psychological benefit of encouraging more breastfeeding and kangaroo care. Both good things.
Making the leap
For ELBW and VLBW infants humidity is required then of course they need this climate controlled environment. Typically once this is no longer needed units will generally try infants out of the incubator when the temperature in the “house” is reduced to 28 degrees. Still though, it is not uncommon to hear that an infant is “too small”. Where is the threshold though that defines being too small? Past research studies have looked at two points of 1600 vs 1800g for the smallest of infants. One of these studies was a Cochrane review by New K, Flenady V, Davies MW. Transfer of preterm infants for incubator to open cot at lower versus higher body weight. Cochrane Database Syst Rev 2011;(9). This concluded that early transition was safe for former ELBWs at the 1600g weight cut off.
Infants in this gestational age range with a birth weight <1600g were randomly assigned to a weaning weight of 1600 or 1800 g. Within 60 to 100 g of weaning weight, the incubator temperature was decreased by 1.0°C to 1.5°C every 24 hours until 28.0°C. Weaning to the crib occurred when axillary temperatures were maintained 36.5°C to 37.4°C for 8 to 12 hours. Clothing and bedcoverings were standardized. The primary outcome was LOS from birth to discharge.
What did they find?
A total of 366 babies were enrolled (187 at 1600g and 179 at 1800g. Baseline characteristics of the two groups revealed no statistical differences. Mean LOPS was a median of 43 days in the lower and 41 days in the higher weight group (P = .12). After transition to a crib weight gain was better in the lower weight group, 13.7 g/kg/day vs 12.8 g/kg/ day (P = .005). Tracking of adverse events such as the incidence of severe hypothermia did not differ between groups. The only real significant difference was a better likelihood of weaning from the incubator in the higher group at 98% success vs 92% on the first attempt. Putting. That in perspective though, a 92% success rate by my standards is high enough to make an attempt worthwhile!
The authors have essentially shown that whether you wean at the higher or lower weight threshold your chances of success are pretty much the same. Curiously, weight gain after weaning was improved which seems counter intuitive. I would have thought that these infants would have to work extra hard metabolically to maintain their temperature and have a lower weight gain but that was not the case. Interestingly, this finding has been shown in another study as well; New K, Flint A, Bogossian F, East C, Davies MW. Transferring preterm infants from incubators to open cots at 1600 g: a multicentre randomised controlled trial. Arch Dis Child Fetal Neonatal Ed 2012;97:F88-92. Metabolic rate has been shown to increase in these infants but skin fold thickness has been shown to increase as well in infants moved to a crib. How these two things go together is a little beyond me as I would have thought that as metabolic rate increases storage of tissue would slow. Not apparently the case but perhaps just another example of the bodies ability to overcome challenges when put in difficult situations. A case maybe of “what doesn’t kill you makes you stronger?”
The authors do point out that the intervention was unmasked but the standardization of weaning procedure and garments used in the cribs should have overcome that. There were 36% of parents who did not consent to the study so their inclusion could have swayed the results perhaps but the sample size here was large despite that. That the final results agree with findings in ELBW infants suggests that the results are plausible.
What I think this study does though is tell us overall that weaning at a smaller weight is at least alright to try once one is at minimal settings in an incubator. Will this change your units practice? It is something that at least merits discussion.
One of the first things a student of any discipline caring for newborns is how to calculate the apgar score at birth. Over 60 years ago Virginia Apgar created this score as a means of giving care providers a consistent snapshot of what an infant was like in the first minute then fifth and if needed 10, 15 and so on if resuscitation was ongoing. For sure it has served a useful purpose as an apgar score of 0 and 0 gives one cause for real worry. What about a baby with an apgar of 3 and 7 or 4 and 8? There are certainly infants who have done very well who initially had low apgar scores and conversely those who had higher apgar scores who have had very significant deleterious outcomes including death. I don’t mean to suggest that the apgar scores don’t provide any useful predictive value as they are used as part of the criteria to determine if a baby merits whole body cooling or not. The question is though after 60+ years, has another score been created to provide similar information but enhance the predictive value derived from a score?
The Neonatal Resuscitation and Adaptation Score (NRAS)
Back in 2015 Jurdi et al published Evaluation of a Comprehensive Delivery Room Neonatal Resuscitation and Adaptation Score (NRAS) Compared to the Apgar Score. This new score added into a ten point score resuscitative actions taken at the 1 and 5 minute time points to create a more functional score that included interventions. The other thing this new score addressed was more recent data that indicated a blue baby at birth is normal (which is why we have eliminated asking the question “is the baby pink?” in NRP. Knowing that, the colour of the baby in the apgar score may not really be that relevant. Take for example a baby with an apgar score of 3 at one minute who could have a HR over 100 and be limp, blue and with shallow breathing. Such a baby might get a few positive pressure breaths and then within 10 seconds be breathing quite well and crying. Conversely, they might be getting ongoing PPV for several minutes and need oxygen. Were they also getting chest compressions? If I only told you the apgar score you wouldn’t have much to go on. Now look at the NRAS and compare the information gathered using two cardiovascular (C1&2), one neurological test (N1) and two respiratory assessments (R1&2).
The authors in this study performed a pilot study on only on 17 patients really as a proof of concept that the score could be taught and implemented. Providers reported both scores and found “superior interrater reliability (P < .001) and respiratory component reliability (P < .001) for all gestational ages compared to the Apgar score.”
A Bigger Study Was Needed
The same group in 2018 this time led by Witcher published Neonatal Resuscitation and Adaptation Score vs Apgar: newborn assessment and predictive ability. The primary outcome was the ability of a low score to predict mortality with a study design that was a non-inferiority trial. All attended deliveries were meant to have both scores done but due to limited numbers of trained personnel who could appropriately administer both scores just under 90% of the total deliveries were assigned scores for comparison. The authors sought to recruit 450 infants to show that a low NRAS score (0–3) would not be inferior to a similar Apgar at predicting death. Interestingly an interim analysis found the NRAS to be superior to Apgar when 75.5% of the 450 were enrolled, so the study was stopped. What led the apgar score to perform poorly in predicting mortality (there were only 12 deaths though in the cohort) was the fact that 49 patients with a 1 minute apgar score of 0-3 survived compared to only 7 infants with a low NRAS score.
The other interesting finding was the ability of the NRAS to predict the need for respiratory support at 48 hours with a one minute apgar score of 0-3 being found in 39% of those on support compared to 100% of those with a low NRAS. Also at 5 minutes a score of 4-6 for the apgar was found in 48% of those with respiratory support at 48 hours vs 87% of those with a similar range NRAS. These findings were statistically significant while a host of other conditions such as sepsis, hypoglycemia, hypothermia and others were no different in terms of predictive ability of the scores.
An Even Bigger Study is Needed
To be sure, this study is still small and missed just over 90% of all deliveries so it is possible there is some bias that is not being detected here. I do think there is something here though which a bigger study that has an army of people equipped to provide the scoring will add to this ongoing story. Every practitioner who resuscitates an infant is asked at some point in those first minutes to hour “will my baby be ok?”. The truth is that the apgar score has never lived up to the hope that it would help us provide an accurate clairvoyant picture of what lies ahead for an infant. Where this score gives me hope is that a score which would at the very least help me predict whether an infant would likely still be needing respiratory support in 48 hours provides the basic answer to the most common question we get in the unit once admitted; “when can I take my baby home”. Using this score I could respond with some greater confidence in saying “I think your infant will be on support for at least 48 hours”. The bigger question though which thankfully we don’t have to address too often for the sickest babies at birth is “will my baby survive?”. If a larger study demonstrates this score to provide a greater degree of accuracy then the “Tipping Point” might just be that to switching over to the NRAS and leaving the apgar score behind. That will never happen overnight but medicine is always evolving and with time you the reader may find yourself becoming very familiar with this score!
It has been a few months now that I have been serving as Chair of the Fetus and Newborn Committee for the Canadian Pediatric Society. Certain statements that we release resonate strongly with me and the one just released this week is certainly one of them. Guidelines for vitamin K prophylaxis in newborns is an important statement about a condition that thankfully so few people ever experience. To read the statement on the CPS website click here.
Similar story to vaccinations
Prior to the American Academy of Pediatrics in 1961 proclaiming that all newborns should receive IM Vitamin K at birth the incidence of Vitamin K deficient bleeding was 0.25 – 1.7%. Think about that for a moment. A new parent could expect that 1/100 babies roughly might have intestinal bleeding or worse an intracranial hemorrhage due to an insufficient amount of vitamin K levels in the newborn. The types of bleeding could be categorized into three different time epochs. Early onset (occurring in the first 24 hours post-birth), classic (occurring at days 2 to 7) and late onset (at 2 to 12 weeks and up to 6 months of age).
With a rate that high detractors of providing Vitamin K at birth would say “why should we give it; I haven’t heard of any baby getting such bleeding?” Looking at it another way though, why don’t you see congenital rubella or kids with measles much these days? It’s due to vaccination. Thankfully as a Neonatologist, I don’t see Vitamin K deficient bleeding since most parents provide Vitamin K to their babies at birth. If you went back to the era prior to 1961 when widespread supplementation of Vitamin K began in the US, I imagine it would not have been too uncommon to hear about a baby who had bleeding issues after birth. Just because we don’t hear about German Measles much anymore doesn’t mean the virus causing it doesn’t still exist!
How Effective is Vitamin K?
How effective is Vitamin K administration at birth in preventing hemorrhagic disease of the newborn (HDNB)? Studies estimate an incidence of 0.25 per 100000 live births or 1 in 400000 babies vs the 1/100 risk without any vitamin K. That is one effective intervention! At this point I would ask those families that are still concerned about giving Vitamin K to their infants if this is a risk they can accept? If they refuse Vitamin K and there is a significant bleed how will they react?
The Change in this CPS Statement From the Past
In the last statement on Vitamin K, the authors suggested that the oral route was a reasonable option. Instead of giving 1 mg of Vitamin K IM one would dose it as 2 mg orally and then repeat at 2-4 weeks and then 6-8 weeks. In looking at the effectiveness though it is worth noting that while we can assure that families will get the first dose, as with any medication that needs repeat dosing there is the risk of forgetfulness leading to missed dosing down the road. In fact when the authors looked at the risk of late HDNB they found the following “The relative risk for VKDB, when comparing PO versus IM vitamin K administration in these two studies, was 28.75 (95% CI 1.64 to 503.45) and 5.97 (95% CI 0.54 to 65.82), respectively .”
The outcome of course remains rare but the risk based on two studies was almost 30 times higher than if IM dosing was given.
On this basis IM is recommended.
Having said all this I recognize that despite all this information, some families will choose for a number of reasons to still opt for the oral dose. As the statement suggests we need to encourage such use when a family refuses IM vitamin K. The 30 fold risk compared to IM administration is magnitudes lower than the approximate 1/100 risk of giving nothing at all!
In the end I believe that one case of intracranial hemorrhage from inadequate vitamin K is too much. This one vitamin indeed could save a life.
It is hard to believe but it has been almost 3 years since I wrote a piece entitled A 200 year old invention that remains king of all tech in newborn resuscitation. In the post I shared a recent story of a situation in which the EKG leads told a different story that what our ears and fingers would want us to believe. The concept of the piece was that in the setting of pulseless electrical activity (where there is electrical conductance in the myocardium but lack of contraction leaves no blood flow to the body) one could pick up a signal from the EKG leads when there is in fact no pulse or perfusion to vital organs. This single experience led me to postulate that this situation may be more common than we think and the application of EKG leads routinely could lead to errors in decision making during resuscitation of the newborn. It is easy to see how that could occur when you think about the racing pulses of our own in such situations and once chest compressions start one might watch the monitor and forget when they see a heart rate of 70 BPM to check for a corresponding pulse or listen with the stethoscope. I could see for example someone stopping chest compressions and continuing to provide BVM ventilation despite no palpable pulse when they see the QRS complex clearly on the monitor. I didn’t really have much evidence to support this concern but perhaps there is a little more to present now.
A Crafty Animal Study Provides The Evidence
I haven’t presented many animal studies but this one is fairly simple and serves to illustrate the concern in a research model. For those of you who haven’t done animal research, my apologies in advance as you read what happened to this group of piglets. Although it may sound awful, the study has demonstrated that the concern I and others have has is real.
For this study 54 newborn piglets (equivalent to 36-38 weeks GA in humans) were anesthetized and had a flow sensor surgically placed around the carotid artery. ECG leads were placed as well and then after achieving stabilization, hypoxia was induced with an FiO2 of 0.1 and then asphyxia by disconnecting the ventilator and clamping the ETT. By having a flow probe around the carotid artery the researchers were able to determine the point of no cardiac output and simultaneously monitor for electrical activity via the EKG leads. Auscultation for heart sounds was performed as well.
The results essentially confirm why I have been concerned with an over reliance on EKG leads.
Of the 57 piglets, 14 had asystole and no carotid flow but in 23 there was still a heart rate present on the EKG with no detectable carotid flow. This yields a sensitivity of only 37%. Moreover, the overall accuracy of the ECG was only 56%.
Meanwhile the stethoscope which I have referred to previously as the “king” in these situations had 100% sensitivity so remains deserving of that title.
What do we do with such information?
I think the results give us reason to pause and remember that faster isn’t always better. Previous research has shown that signal acquisition with EKG leads is faster than with oximetry. While a low heart rate detected quickly is helpful to know what the state of the infant is and begin the NRP pathway, we simply can’t rely on the EKG to tell us the whole story. We work in interdisciplinary teams and need to support one another in resuscitations and provide the team with the necessary information to perform well. The next time you are in such a situation remember that the EKG is only one part of the story and that auscultation for heart sounds and palpation of the umbilical cord for pulsation are necessary steps to demonstrate conclusively that you don’t just have a rhythm but a perfusing one.
I would like to thank the Edmonton group for continuing to put out such important work in the field of resuscitation!
Hi, my name is Diane Schultz and Michael has asked me to write a series of posts on his blog about Kangaroo Care (KC). Seeing as I am one of the Champions (they call you that, but sometimes the word begins with a B) for KC in my unit, I was thrilled. I thought I would begin with an introduction as to why I want to write about this.
I have been a Neonatal Nurse for 29 years working in the NICU at St. Boniface Hospital in Winnipeg. I felt that I had always given good care to the families but did not really make connections with them.
I was fortunate enough to meet Dr. Susie Ludington about 10 years ago at an Academy of Neonatal Nursing conference. She was a general session presenter and was speaking about Kangaroo Care. The first thing she said was “My goal is Kangaroo Care 24/7”. All I could think of was WTF!? I would have to listen to this Nutbar for an hour? Our unit had been doing KC for years but only occasionally and usually the parent would ask for it, we certainly did not promote it or do it with our more fragile infants.
After listening to Dr. Ludington present, my world changed. What she said hit a cord; she presented benefit after benefit with rationale and evidence that made complete sense to me. I felt guilty I had not been doing this at work and guilty that I had not held my own daughters this way. I am now lucky to be able to call Dr. Ludington a friend, and know she has changed my life.
Now, there is a lot of evidence out there touting the benefits of KC, but the real way to understand and believe in it is to do it. KC creates its own evidence. Every time I bring out a medically fragile infant to be held in KC, I know that this is the right place for that infant to be: with their parent being held. You can see the relaxation on all of their faces (decreasing cortisol), the infant is able to go into a deep sleep (promotes brain maturation), and the family is able to connect in the best way possible. I feel KC is as important as anything else we do at the bedside and is an extremely necessary therapy.
Promoting KC in my unit has benefited me at so many levels; I believe it has actually saved my career and given me a focus that I didn’t have before. You can’t help but make connections with your families, and these families are able to make connections with their little ones. KC is also a very important part of Family Integrated Care, as this is something that the family can contribute to their child’s care.
I also couldn’t be more proud of my unit; the staff I have the pleasure to work with are some of the best health care professionals around. They make every effort to bring our fragile infants out for KC and it has become part of our culture in our NICU. KC happens in our unit with almost all of our infants, the only exceptions being actively cooling babies and infants with chest tubes. We have also created a Standard Work Protocol so all medically fragile infants come out the safest way possible without creating extra stress on the infant or family.
In my series of posts I will present the many benefits of KC for infants and their families and share some of my experiences. I hope you will be able to take something away from this, begin to try KC in your own unit, and create your own evidence.