Look around you. Technology is increasingly becoming pervasive in our everyday lives both at home and at work. The promise of technology in the home is to make our lives easier. Automating tasks such as when the lights turn on or what music plays while you eat dinner (all scripted) are offered by several competitors. In the workplace, technology offers hopes of reducing medical error and thereby enhancing safety and accuracy of patient care. The electronic health record while being a nuisance to some does offer protection against incorrect order writing since the algorithms embedded in the software warn you any time you stray. What follows is a bit of a story if you will of an emerging technology that has caught my eye and starts like many tales as a creative idea for one purpose that may actually have benefits in other situations.
In 2012 students in Australia rose to the challenge and designed a digital stethoscope that could be paired with a smartphone. The stethoscope was able to send the audio it was receiving to the smartphone for analysis and provide an interpretation. The goal here was to help diagnose childhood pneumonia with a stethoscope that would be affordable to the masses, even “Dr. Mom” as the following video documents. Imagine before calling your health line in your city having this $20 tool in your hands that had already told you your child had breath sounds compatible with pneumonia. Might help with moving you up the triage queue in your local emergency department.
Shifting the goal to helping with newborns
Of course breath sounds are not the only audio captured in a stethoscope. Heart sounds are captured as well and the speed of the beats could offer another method of confirming the heart is actually beating. Now we have ECG, pulse oximetry, auscultation and palpation of the umbilical stump to utilize as well so why do you need another tool? It comes down to accuracy. When our own heart rates are running high, how confident are we in what we feel at the stump (is that our own pulse we are feeling?). In a review on measurement of HR by Phillipos E et al from Edmonton, Alberta, auscultation was found to take an average of 17 seconds to produce a number and in 1/3 of situations was incorrect. The error in many cases would have led to changes in management during resuscitation. Palpation of the umbilical cord is far worse. In one study “cord pulsations were impalpable at the time of assessment in 5 (19%) infants, and clinical assessment underestimated the ECG HR with a mean (SD) difference between auscultation and palpation and ECG HR of − 14 (21) and − 21 (21) beats min –1″. In another study, 55% of the time providers were incorrect when they thought the HR was under 100 BPM. This leaves the door open for something else. Might that something be the digital stethoscope?
How does the digital stethoscope fare?
Kevac AC et al decided to look at the use of the Stethocloud to measure HR after birth in infants >26 weeks gestational age at birth. The opted to use the ECG leads as the gold standard which arguably is the most accurate method we have for detecting HR. The good news was that the time to signal acquisition was pretty impressive. The median time to first heart rate with the stethoscope was 2 secs (IQR 1-7 seconds). In comparison the time for a pulse oximeter to pick up HR is variable but may be as long as one minute. In low perfusion states it may be even longer or unable to pick up a good signal. The bad news was the accuracy as shown in the Bland Altman plot. The tendency of the stethoscope was to underestimate the EKG HR by about 7 BPM. Two standard deviations though had it underestimate by almost 60 BPM or overestimate by about 50 BPM. For the purposes of resuscitation, this range is far to great. The mean is acceptable but the precision around that mean is to wide. The other issue noted was the frequent missing data from loss of contact with the patient. Could you imagine for example having a baby who has a heart rate of 50 by the stethoscope but by EKG 100? Big difference in approach, especially if you didn’t have EKG leads on to confirm. The authors note that the accuracy is not sufficient and felt that an improvement in the software algorithms might help.
Another go at it
So as suggested, the same group after having a new version with improved software decided to go at it again. This time Gaertner VD et al restricted the study to term infants. Forty four infants went through the same process again with the stethoscope output being compared to EKG lead results. This time around the results are far more impressive. There was virtually no difference between the ECG and the stethoscope with a 95% confidence interval as shown in the graphs with A being for all recordings and B being those without crying (which would interfere with the acquiring of HR). A maximal difference of +/- 18 BPM for all infants is better than what one gets with auscultation or palpation in terms of accuracy and let’s not forget the 2 second acquisition time!
Should you buy one?
I think this story is evolving and it wouldn’t surprise me if we do see something like this in our future. It certainly removes the element of human error from measuring. It is faster to get a signal than even the time it takes to get your leads on. Where I think it may have a role though is for the patient who has truly no pulse. In such a case you can have an EKG HR but the patient could be in pulseless electrical activity. Typically in this case people struggle to feel a pulse with the accuracy being poor in such situations. Using a device that relies on an actual heart contraction to make a sound provides the team with real information. Concurrent with this technology is also the rise of point of care ultrasound which could look at actual cardiac contractions but this requires training that makes it less generalizable. Putting a stethoscope on a chest is something we all learn to do regardless of our training background.
I think they could be on to something here but perhaps a little more evidence and in particular a study in the preterm infant would be helpful to demonstrate similar accuracy.
I don’t envy our nurses who care for babies withdrawing from various opiates and other substances. These assignments are definitely a challenge and require a great deal of patience and depending on the shrillness of an infant’s cry a good set of earplugs. Nonetheless we do our best with these infants to keep them calm and avoid as much stimulation as we can as we attempt to minimize the excitability of their nervous system.
Over 40 years ago the Finnegan Neonatal Abstinence scoring system was developed to assist medical teams by providing as objective a system as possible to compare one infant to another and determine when and if a patient should be treated pharmacologically. Unfortunately there is a problem inherent with this scoring system. It is the same problem that exists when you don’t have a blinded research trial. Imagine you are caring for an infant and you were given no history about drug exposure. How might you score a patient like that compared to one in which you are told has been exposed to illicit substances? Your senses are heightened and moreover if you were told this baby is “withdrawing terribly” or “is awful at night” you are biased. How are you likely to score such a patient when they are “on the edge” of being counted as a 1 or a 0 in a category? I bet in many cases, especially if you haven’t taken care of many such patients you err on the side of caution and score them on the high side. It is human nature. When the possible outcome of failing to recognize a withdrawing patient is a seizure, no one wants to be on when it happens having their scoring questioned. Have a look at the scoring tool though.
There is a lot of stuff in there to check off! What if it could be simpler?
The ESC Tool
In early May, news began to break of an abstract being presented at the Pediatric Academic Society meeting. The news story from the AAP can be found here. The ESC tool is a three question tool used to assess whether an infant requires treatment for withdrawal.
E – Eat (is an infant is able to eat 1 or more ounce per feeding)
S – Sleeping (sleep for an hour or longer undisturbed)
C – Console (Be consoled in 10 minutes or less.)
If all three criteria are met, the patient does not need treatment. If one or more criteria are not met the housestaff are notified and first non-pharmacologic and then pharmacologic means are employed if necessary to control symptoms.
The authors did something quite interesting. They looked at 50 patients with 201 hospital days with prenatal exposures to opiates and applied the ESC criteria to guide treatment. Concurrently they captured the Finnegan scores but did not use them to guide treatment.
The findings I hope you will agree are quite interesting!
“FNASS scores indicated starting morphine in 30 infants (60%). Morphine was actually started on only 6 patients (12%) (p< 0.0001) based on the ESC approach. The FNASS led protocol directed initiating or increasing meds on 24.6% of days compared to 2.7% of days using the ESC approach (p< 0.0001). The FNASS approach directed that morphine was either not started or decreased on 65.8% of days compared with 94.4% of days using the ESC approach (p< 0.0001). There were no readmissions or reported adverse events.
Pretty amazing but…
The ESC approach greatly reduced the need for treatment and as the authors state there were no readmissions or reported adverse events. What we don’t know and will be needed I suspect before anyone will adopt this strategy (which I have to say again is so much simpler that current approaches) is how these children do in the long run. If the system is undertreating withdrawal, could we see downstream impacts of a “kinder and gentler” approach? One outcome that will be reported soon in the next month is length of stay. I am eagerly awaiting further results as I for one think that a simpler approach to these patients may be just what the doctor ordered. I think the nurses might thank us as well but we will see just how appropriate it is!
The Abstract reporting these findings can be found below
I have often said that if this came to pass as a mandatory requirement that I would make an announcement shortly thereafter that I was moving on to another career. I think people thought I was kidding but I can put in writing for all to see that I am serious! The subject has been discussed for some time as I can recall such talks with colleagues both in my current position and in other centres. The gist of the argument for staying in-house is that continuity is improved over that period and efficiency gained by avoiding handovers twice a day . How many times have you heard at signover that extubation will be considered for the following morning or to keep the status quo for another issue such as feeding until the next day. No doubt this is influenced by a new set of eyes being in the unit and a change in approach to being one of “putting out fires” overnight. The question then is whether having one Neonatologist there for 24 hours leads to better consistency and with it better outcomes. With respect to PICUs the AAP has previously recommended that 24 hour in-house coverage by an intensivist be the standard so should Neonatology follow suit?
A Tale of Two Periods
My friends in Calgary, Alberta underwent a change in practice in 2001 in which they transitioned from having an in-house model of Neonatologist coverage for 24 hours a day to one similar to our own centres where the Neonatologist after handover late afternoon could take call from home. An article hot off the presses entitled Twenty-Four hour in-house neonatologist coverage and long-term neurodevelopmental outcomes of preterm infants seeks to help answer this question. The team undertook a retrospective analysis of 387 infants born at < 28 weeks gestational age during the periods of 1998-2000 (24 hour period, N=179 infants) vs 2002 – 2004 (day coverage, N= 208 infants) with the goal of looking at the big picture being follow-up for developmental outcome at 3 years. This is an important outcome as one can look at lots of short term outcomes (which they also did) but in the end what matters most is whether the infants survive and if they do are they any different in the long term.
As with any such study it is important to look at whether the infants in the two periods are comparable in terms of risk factors for adverse outcome. Some differences do exist that are worth noting.
Increased risk factors in the 24 hour group
Smaller birthweight (875 vs 922 g)
Confirmed sepsis (23% vs 14%)
Postnatal steroids (45% vs 8%) – but duration of ventilation longer in the day coverage group likely due to less postnatal steroids ( 31 vs 21 days)
All of these factors would predict a worse outcome for these infants but in the end for the primary outcome of neurodevelopmental impairment there was no difference. Even after controlling for postnatal steroids, birth weight, sex and 5 minute apgar score there was still no difference.
What might this mean?
Looking at this with a glass is half full view one might say that with all of the factors above predicting worse outcome for infants, the fact that the groups are not different in outcome may mean that the 24 hour model does indeed confer a benefit. Maybe having a Neonatologist around the clock means that care is made that much better to offset the effect of these other risk factors? On the other hand another explanation could also be that the reason there is no difference is that the sample just isn’t big enough to show a difference. In other words the size of the study might be underpowered to find a difference in developmental outcome.
One of the conclusions in this study is that the presence of a Neonatologist around the clock may have led to earlier extubation and account for the nearly 10 day difference in duration of ventilation. While I would love to believe that for personal reasons I don’t think we can ignore the fact that in the earlier epoch almost 50% of the babies received postnatal steroids compared to 8% in the later period. Postnatal steroids work and they do so by helping us get babies off ventilators. It is hard to ignore that point although I woudl like to take credit for such an achievement.
For now it would appear that I don’t feel compelled to stay overnight in the hospital unless it is necessary due to patient condition necessitating me having my eye on the patient. I am not sure where our field will go in the future but for now I don’t see the evidence being there for a change in practice. With that I will retire to my bedroom while I am on call and get some rest (I hope).
Aside from me donning the costume in the above picture for the Kangaroo Challenge 2017 I learned something new today. Before I get into what I learned, let me say that I had the opportunity to put so many smiles on parents faces by walking around in this full body costume that I am grateful to Diane for finding this costume and Sue (you both know who you are) for purchasing it. Handing out cookies to the parents and children at the bedside and seeing them smile while knowing that they were under significant stress gave me the opportunity to interact with parents in a very different way than I am accustomed to as a Neonatologist so I am so thankful to have had that experience and yes if called upon I will do it again!
I posted the above picture on my Facebook page and to my surprise many of the comments led me to believe that Kangaroo Care is still something that needs a little nudging to get the word out about. I found this actually quite surprising given how immersed we are in Winnipeg with this strategy. When I think about new interventions in Neonatology it is synonymous in virtually all cases with an influx of dollars to achieve usher in the new program. Here is a program that is virtually free but only requires a commitment from families to spend the time at the bedside with their baby in the NICU.
I have been asked by many of my nursing colleagues to write something about Kangaroo care on this site and so here it is…
What is it?
You have likely heard of Kangaroo Care and you may have even seen some children receiving it in your hospital. Why is this so important?
Kangaroo Care (KC) or Skin to Skin Care (STS) is an ideal method of involving parents in the care of their premature infant. It fosters bonding between parents and their hospitalized infant, encourages the family to be with their child and thereby exposes them to other elements of neonatal care that they can take part in. While we know that many units are practising Kangaroo Care there is a big difference between having KC in your unit and doing everything you can to maximize the opportunity that your families have to participate.
There is much more to KC than simply holding a baby against your chest. For a demonstration of KC please watch the accompanying video and show it to any one in your units that may need a visual demonstration. This excellent video is from Nationwide Children’s Hospital and walks you through all of the important steps to get it right and maximize benefit.
Before you reach the conclusion that KC only serves to enhance the parental experience it does so much more than that. The practice began in Bogota Columbia in 1979 in order to deal with a shortage of incubators and associated rampant hospital infections. The results of their intervention were dramatic and lead to the spread of this strategy worldwide. The person credited with helping to spread the word and establish KC as a standard of care in many NICUs is Nils Bergman and his story and commentary can be found here http://bit.ly/1cqIXlm
The effects of KC are dramatic and effective to reduce many important morbidities and conclusively has led to a reduction in death arguably the most important outcome. An analysis of effect has been the subject of several Cochrane Collaboration reviews with the most recent one being found here.
To summarize though, the use of KC or STS care has resulted in the following overall benefits to premature infants at discharge or 40 – 41 weeks’ postmenstrual age:
mortality (typical RR 0.68, 95% CI 0.48 to 0.96)
nosocomial infection/sepsis (typical RR 0.57, 95% CI 0.40 to 0.80)
hypothermia (typical RR 0.23, 95% CI 0.10 to 0.55)
KMC was found to increase some measures of infant growth, breastfeeding, and mother-infant attachment
To put this in perspective, medicine is littered with great medications that never achieved such impact as simply putting your child against your chest. This is another shining example of doing more with less. This is not to say that modern medicine and technology does not have its place in the NICU but KC is simply too powerful a strategy not to use and promote routinely in the NICU.
Please join me in championing this wonderful technique and make a difference to all of our babies!
A sample of our parent letter to promote KC is found in the link below.
The infant car seat challenge(ICSC) is a test which most definitely fits the definition of a battleground issue in Neonatology. After publishing the Canadian Pediatric Practice point on the same topic I received interesting feedback through the various social media forums that I frequent. While some were celebrating the consensus of the statement as verification that a centres’ non practice of the test was acceptable, others seriously questioned the validity of the position. The naysayers would point out that extremely infrequent events unless intentionally tracked may be difficult to pick up. In the case of the ICSC, if a few patients were to suffer a hypoxic event leading to an ALTE or worse after discharge, could the ICSC have picked out these babies and prevented the outcome? The evidence for adverse events associated with the use of car seats as discussed in the position statement is poor when using autopsy records over decades but when many clinicians can point to a failed ICSC picking up events, the thought goes that they “caught one”. Does catching one make a difference though?
The Well Appearing Infant
Shah et al in their recent paper Clinical Outcomes Associated with a Failed Infant Car Seat Challenge attempt to address this very point. They performed a retrospective study of 148 patients who were either <37 weeks GA or < 2500g at birth. The study was made possible by the fact that all such infants in their hospital admitted to a well newborn area meeting these criteria by policy must have an ICSC prior to discharge. Keep in mind that these were all infants who were on the well newborn service since they were asymptomatic. The definition of an event in this group was one or more of pulse oximeter saturation ≤ 85% for > 10 seconds, apnea > 20 seconds, bradycardia < 80 bpm for > 10 seconds, or an apnea or bradycardia event requiring stimulation. The failure rate was 4.5% which is very similar to other reported studies.
Why did they “fail”?
Failure of the ICSC was owing to desaturation 59%
Combination of 2 in 11%
What is interesting about these results is what happened to these infants after admission to the NICU in that 39% were identified with apnea (48% in preterm vs 17% in term infants). These events were in the supine position which is a curious finding since the ICSC was designed to find risk of cardiorespiratory stability in a semi-recumbent position. This has been shown previously though.
What does it all mean?
The infants in this study ultimately had more NG feeding, prolonged length of stay and septic workups after failing the ICSC that comparable infants who passed. At first blush one would read this article and immediately question the validity of the CPS position but then the real question is what has this added to the “pool of knowledge”. That infants may fail an ICSC at a rate of 4.5% is already known. That such infants may demonstrate apneic events has also been shown before and a study like this may help to support those clinicians who feel it is still imperative to find these infants in order to achieve a safe discharge. I think it is important to put these findings in the context of what would have happened if such a unit did not routinely test these types of babies. As all were seemingly well and I presume feeding with their families, they would have been discharged after 24-48 hours to home. We have no evidence (since they have not compared this sample to a group who did not have such testing) that if these babies were discharged they would have faired poorly.
The supporters of the ICSC would point to all the support these babies received by admitting them for 6-8 days, providing NG feeding and ruling out sepsis that they were unsafe for discharge. The other possible way to look at it was that the infants were subjected to interventions that we have no evidence helped them. Whether any of these infants had a positive blood culture justifying antibiotics or needed methylxanthine support is not mentioned. Judging however by the short length of stay I suspect that none or few of these infants needed such medication as I would expect they would have stayed much longer had they needed medical treatment for apnea.
I do commend the authors for completing the study and while it does raise some eyebrows, I don’t see it changing at least my position on the ICSC. While they have described a cohort of patients who failed the ICSC nicely, the fundamental question has been left unanswered. Does any of this matter? If you look well, are feeding well and free of any clinically recognizable events but are late preterm or IUGR can the ICSC prevent harm? This has not been answered here and perhaps the next step would be for a centre that has abandoned the ICSC to follow their patients after discharge prospectively and see whether any adverse outcomes do indeed occur. Any takers?
Positive pressure ventilation puts infants at risk of developing chronic lung disease (CLD). Chronic lung disease in turn has been linked many times over, as a risk for long term impacts on development. So if one could reduce the amount of positive pressure breaths administered to a neonate over the course of their hospital stay, that should reduce the risk of CLD and by extension developmental impairment. At least that is the theory. Around the start of my career in Neonatology one publication that carried a lot of weight in academic circles was the Randomized Trial of Permissive Hypercapnia in Preterm Infants which randomized 49 surfactant treated infants to either a low (35-45) or high (45-55) PCO2 target with the thought being that allowing for a higher pCO2 should mean that lower settings can be used. Lower settings on a ventilator would lead to less lung damage and therefore less CLD and in turn better outcomes. The study in question did show that the primary outcome was indeed different with almost a 75% reduction in days of ventilation and with that the era of permissive hypercapnia was born.
The Cochrane Weigh in
In 2001 a systematic review including this and another study concluded that there was insufficient evidence to support the strategy in terms of a benefit to death or chronic lung disease. Despite this lack of evidence and a recommendation from the Cochrane group that permissive hypercapnia be used only in the context of well designed trials the practice persisted and does so to this day in many places. A little lost in this discussion is that while the end point above was not different there may still be a benefit of shorter term ventilation.
A modern cohort
It would be unwise to ignore at this point that the babies of the late 90s are different that the ones in the current era. Surfactant and antenatal steroid use are much more prevalent now. Ventilation strategies have shifted to volume as opposed to pressure modes in many centres with a shift to early use of modalities such as high frequency ventilation to spare infants the potential harm of either baro or volutrauma. Back in 2015 the results of the PHELBI trial were reported Permissive hypercapnia in extremely low birthweight infants (PHELBI): a randomised controlled multicentre trial. This large trial of 359 patients randomized to a high or low target pCO2 again failed to show any difference in outcomes in terms of the big ones “death or BPD, mortality alone, ROP, or severe IVH”. What was interesting about this study was that they did not pick one unified target for pCO2 but rather set different targets as time went on reflecting that with time HCO3 rises so what matters more is maintaining a minimum pH rather than targeting a pCO2 alone which als0 reflects at least our own centre’s practice. There is a fly in the ointment here though and that is that the control group has a fault (at least in my eyes)
Day of life
In the original studies of permissive hypercapnia the comparison was of a persistent attempt to keep normal pCO2 vs allowing the pCO2 to drift higher. Although I may get some argument on this point, what was done in this study was to compare two permissive hypercapnia ranges to each other. If it is generally accepted that a normal pCO2 is 35-45 mmHg then none of these ranges in the low target were that at all.
How did these babies do in the long run?
The two year follow-up for this study was published in the last month; Neurodevelopmental outcomes of extremely low birthweight infants randomised to different PCO2 targets: the PHELBI follow-up study. At the risk of sounding repetitive the results of Bayley III developmental testing found no benefit to developmental outcome. So what can we say? There is no difference between two strategies of permissive hypercapnia with one using a higher and the other a lower threshold for pCO2. It doesn’t however address the issue well of whether targeting a normal pCO2 is better or worse although the authors conclude that it is the short term outcomes of shorter number of days on ventilation that may matter the most.
The Truth is Out There
I want to believe that permissive hypercapnia makes a difference. I have been using the strategy for 15 or so years already and I would like to think it wasn’t poor strategy. I continue to think it makes sense but have to admit that the impact for the average baby is likely not what it once was. Except for the smallest of infants many babies these days born at 27 or more weeks of gestation due to the benefits of antenatal steroids, surfactant and modern ventilation techniques spend few hours to days on the ventilator. Meanwhile the number of factors such chorioamniotitis, early and late onset sepsis and genetic predisposition affect the risks for CLD to a great degree in the modern era. Not that they weren’t at play before but their influence in a period of more gentle ventilation may have a greater impact now. That so many factors contribute to the development of CLD the actual effect of permissive hypercapnia may in fact not be what it once was.
What is not disputed though is that the amount of time on a ventilator when needed is less when the strategy is used. Let us not discount the impact of that benefit as ask any parent if that outcome is of importance to them and you will have your answer.
So has permissive hypercapnia failed to deliver? The answer in terms of the long term outcomes that hospitals use to benchmark against one and other may be yes. The answer from the perspective of the baby and family and at least this Neonatologist is no.