Could this be the perfect home apnea monitor?

Could this be the perfect home apnea monitor?

A question that we are asked from time to time is whether a home apnea monitor should be purchased after discharge from the hospital.  The typical parent is one who has experienced the ups and downs of apnea of prematurity and is faced with the disturbing notion of coming off monitors and going home.  “What if he has an event at home and I don’t know”?  This leads to a search on the web for home monitors which finds numerous options to choose from.  This is where things get interesting from a North American perspective.

In the two centres I have worked at in Canada our answer to such a question is to save your money and not buy one.  Contrast this with two families I know in the US who were sent home by the hospital with home apnea monitors.  How can the advice between the two nations be so different?  I suspect the great risk of a lawsuit in the US is responsible at least in part but it may have to do with risk tolerance as well.

What does the evidence say?

First off, one might surmise that the use of a home apnea monitor helps hospitals move patients to the home faster than those centres that don’t prescribe them.  A 2001 Cochrane systematic review on the subject noted that this was not the case and determined that out of nearly 15000 neonates studied the greatest predictor of sending such babies home on monitors was physician preference.

In the largest home monitoring study of its kind, the Collaborative Home Infant Monitoring Evaluation (CHIME) demonstrated some very important information.  First off, ex-preterm infants have events and some of them quite significant after discharge.  What the study which followed discharged infants at risk of SIDS in the home environment found though was that term infants also have events although less severe.  Does this mean that everyone should run out and buy such monitoring equipment though?  No!  The main reason was that while the study did show that events may continue after discharge, it failed to show that these events had any relation to SIDS.  The apneic events noted in hospital disappeared long before the arrival of a risk for SIDS.  They really are separate entities.

The other issue with such monitors pertains to false alarms which can lead to sleepless nights, anxiety in parents and eventual abandonment of such technology.  This led the AAP in 2005 to declare that they did not endorse such practice.  Having said that, it is clear from my own experience with two US ex-preterm infants that this practice remains alive and well.

Could this be the solution?

One of my followers sent me this tonight and I have to say at the very least I am intrigued.  The device is called the Owlet and was featured in this article  The Sock That Could Save Your Babies Lifeowlet-baby-on-back-with-phone-connected

Watch the video here.

This monitor has me a little excited as it brings the home apnea monitor into the modern era with smart phone connectivity and at the same time helps the developers of this technology use data collected every two seconds to get a clearer picture on breathing patterns in infants that have been sent home.  The saturation monitor in a sock is at the core of this technology which is meant to keep the probe in a relatively stable location.  It brings another angle to the concept of wearable tech!    What I find most interesting is the claim by the manufacturer that the device has a false alarm rate similar to that of a hospital saturation probe which would make it quite reliable.

I note though that the product has not received FDA approval yet (at least on the source I looked at) but is being worked on.  The challenge though is whether this will truly make a difference.  It may well have an excellent detection rate and it may in fact detect true apnea leading to bradycardia and cyanosis.  What it won’t do though is change the natural history of these events once home.  It may capture them very well but I suspect the four events that the mother in the video describes may have been self resolving if she hadn’t intervened.  We know from the CHIME study that the events seen in the home did not lead to death from SIDS so I see no reason why these would be different.

Is it useless?

I suppose that depends on your perspective.  From a data collection point, obtaining data every two seconds in a cloud based storage environment will allow this company to describe the natural history of respiratory patterns in ex-preterm infants better than I suspect has ever been done before.  From a population standpoint I suppose that is something!  At an individual level I suppose it depends on your strength of “needing to know”.  This may well be the best monitor out there and it may one day be the most reliable.  Will it save your baby’s life?  I doubt it but might it give you piece of mind if it false alarms very infrequently?  I think it just might but based on the low likelihood of it changing the outcome of your baby you won’t see me recommending it.  If I come across one make no mistake about it, I will want to play with it myself!

 

 

 

 

 

Walk but don’t run to reduce apnea of prematurity

Walk but don’t run to reduce apnea of prematurity

Now that I have caught your attention it is only fair that I explain what I mean by such an absurd title.  If you work with preterm infants, you have dealt with apnea of prematurity.  If you have, then you also have had to manage such infants who seemingly are resistant to everything other than being ventilated.  We have all seen them.  Due to increasing events someone gives a load of methylxanthine and then starts maintenance.  After a couple days a miniload is given and the dose increased with the cycle repeating itself until nCPAP or some other non-invasive modality is started.  Finally, after admitting defeat due to persistent episodes of apnea and/or bradycardia, the patient is intubated.  This, in the absence of some other cause for apnea such as sepsis or seizures is the methylxanthine resistant preterm infant.  Seemingly no amount of treatment will amount to a reduction in events and then there is only so much that CPAP can do to help.

What Next?

Other strategies have been attempted to deal with such infants but sadly none have really stood the test of time.  Breathing carbon dioxide might make sense as we humans tend to breathe quickly to excrete rising CO2 but in neonates while such a response occurs it does not last and is inferior to methylxanthine therapy.  Doxapram was used in the past and continues to be used in Europe but concerns over impacts on neurodevelopment have been a barrier in North America for some time.  Stimulating infants through a variety of methods has been tried but the downside to using for example a vibrating mattress is that sleep could be interfered with and there are no doubt impacts to the preterm infant of having weeks of disturbed sleep states on developmental outcomes.

What if we could make our preterm infants walk?

This of course isn’t physically practical but two researchers have explored this question by using vibration at proprioceptors in the hand and foot.  Such stimulation may simulate limb movement and trick the brain into thinking that the infant is walking or running.  Why would we do this?.  It has been known for 40 years that movement of limbs as in walking triggers a respiratory stimulatory effect by increasing breathing.  This has been shown in adults but not in infants but this possibility is the basis of a study carried out in California entitled Neuromodulation of Limb Propriceptive Afferents Decreases Apnea of Prematurity and Accompanying Intermittent Hypoxia and Bradycardia.  This was a small pilot study enrolling 19 patients of which 15 had analyzable data.  The design was that of alternating individual preterm infants born between 23 – 35 weeks to receive either vibratory stimulation or nothing and measuring the number and extent of apnea and bradycardia over these four periods.  In essence this was a proof of concept study.

The stimulation is likened to that felt when a cell phone vibrates as this was the size of device used to generate the sensation.  iphone-6s-plus-home-screen-heroThe authors note that during the periods of stimulation the nurses noted no signs of any infant waking or seeming to be disturbed by the sensation.  The results were quite interesting especially when noting that 80% of the infants were on caffeine during the time of the study so these were mostly babies already receiving some degree of stimulation

Should we run out and buy these?

The stimulation does appear to work but with any small study we need to be careful in saying with confidence that this would work in a much larger sample.  Could there have been some other factor affecting the results?  Absolutely but the results nonetheless do raise an eyebrow.  One thing missing from the study that I hope would be done in a larger sample next time is an EEG.  The authors are speculating that by placing the vibration over the hand and foot the brain is perceiving the signal as limb movement but it would have been nice to see the motor areas of the brain “lighting up” during such stimulation.  As we don’t have that I am left wondering if the vibration was simply a form of mild noxious stimulus that led to these results.  Of course in the end maybe it doesn’t matter if the results show improvement but an EEG could also inform us about the quality of sleep rather than relying on nursing report of how they thought the baby tolerated the stimulus.  I know our nursing colleagues are phenomenal but can they really discern between quiet and active sleep cycles?  Maybe some but I would guess most not.  There will also be the naysayers out there that will question safety.  While we may not perceive a gentle vibration as being harmful, with such a small number of patients can we say that with certainty?  I am on the side of believing it is probably insignificant but then again I tend to see the world through rose coloured glasses.

Regardless of the filter through which you view this world of ours I have to say I am quite excited to see where this goes.  Now we just have to figure out how to manage the “real estate” of our infant’s skin as we keep adding more and more probes that need a hand or a foot for placement!

Your address may be the most important thing when it comes to Synagis and RSV.

Your address may be the most important thing when it comes to Synagis and RSV.

As I said in another post on this topic I have been a huge advocate of RSV prophylaxis since my days as a Pediatric resident. When I started my residency we were not using Palivizumab (Synagis) and I recall admitting 10+ patients per day at times with bronchiolitis.  With the use of passive immunization this rate dropped dramatically in Manitoba although rates in other areas of the country may have not seen such significant impacts.  Manitoba may be somewhat different from many areas due to the communities in Nunavut being so impacted when RSV enters these areas and can infect many of the children due to crowded living conditions and inability to really isolate kids from one and other.  The lack of benefit in other areas though, has no doubt led to controversy among practitioners who often wonder if giving 5 IM injections during the RSV season is indeed worth it.  The real question has not necessarily been does it work but to whom should it be given so that you get the most benefit.

A Big Change in The Last Year

In 2015 the CPS published a revised statement entitled Preventing hospitalizations for respiratory syncytial virus infection.  This statement included a significant change to the recommendation for those who should receive the product.

  • In preterm infants without CLD born before 30 + 0 weeks’ GA who are <6 months of age at the start of RSV season, it is reasonable (but not essential) to offer palivizumab. Infants born after 30 + 0 weeks’ GA have RSV admission rates that are consistently ≤7% (Figure 3), yielding a minimum number needed to treat of 18 (90 doses of palivizumab to prevent one RSV admission) if one assumes 80% efficacy and five doses per infant. Therefore, palivizumab should not be prescribed for this group.

Gone are recommendations for treating those from 30 – 32 weeks and moreover 33- 35 weeks if meeting certain conditions.  There is a provision for those in Northern communities to expand these criteria to 36 0/7 weeks if such infants would require medical transport to receive care for bronchiolitis.  What is not really clear though is what is meant by Northern communities in terms of criteria to determine suitability exactly.

Incidentally, the criteria are not so different than the AAP statement from August 2014.  In their version of the statement they state:

“The burden of RSV disease and costs associated with transport from remote locations may result in a broader use of palivizumab for RSV prevention in Alaska Native populations and possibly in selected other American Indian populations.”

The American guideline also states that it is for those infants who are “well” and under 29 weeks that RSV prophylaxis is appropriate but from 29 – 32 weeks use should be restricted to those babies who are on oxygen at 28 days of life.

AAP News Release From This Week

As stated above there are those who have always been sceptical of the true cost benefit of RSV prophylaxis and I would imagine those individuals must have latched on to the following report. Otherwise healthy premature infants 29 weeks gestation and over unlikely to benefit from palivizumab

The authors of this study found that while during the RSV season admission for RSV bronchiolitis was lower from 29 – 32 weeks in those infants who had received Synagis. This would argue that it should be given in this group except for the fact that as the authors state it was a “wash” since hospitalization for non-RSV bronchiolitis in the same population was increased by a similar amount.  In essence if you didn’t get RSV you wound up getting something else that still put you in hospital.  The conclusion here is that the decision to drop the criterion for prophylaxis to under 29 weeks is supported since from 29 – 32 weeks you can’t prevent hospitalization from viruses that take the place of RSV.

A Few Thoughts Though Before We Conclude It Has No Place

As I stated upfront I am not totally free of bias having seen a very large impact up here in Manitoba.  What I worry about though is that we have in medicine a tendency to try and capture the “gist” of a guideline rather than committing it in its entirety to memory.  We can’t help ourselves as the volume of information we are asked to remember is growing daily.  What this may lead to however is changes to our practice that may expose vulnerable infants.  The AAP guideline was designed to recommend changes for the otherwise healthy infant under 29 weeks.  What I think we are really talking about are the truly exceptional babies.  In our institution babies born at less than 29 weeks and certainly those closer to 24 weeks often spend as much as a month on CPAP. At 28 days even if the patient were on room air it might only be due to the fact that they were on distending pressure.  Put them on nasal prongs and they would qualify.

Another important consideration is the remote location point.  figure35-enHere in Canada the majority of the population lives along the border with the US.  Take a look though at our population density and you can see that for our Aboriginal (Indian) and Inuit populations as well as all those living in the north we have a significant need to protect them.  Living conditions in these places involve overcrowding and high smoking levels both ideal breeding grounds for transmission of RSV and an intolerance to handling the inflammation in your bronchioles.  The same is likely true of many parts of Alaska for my US readers.

It would be too easy to simply state “I only need to give Synagis to those babies under 29 weeks now” but that would do a disservice to the populations in our remote communities both here and in the US.

In case you are wondering, I am not employed by the makers of Synagis here or in the US nor do I have any financial or conflicts otherwise.  I am someone I suppose who has seen the difference of before and after and while I will let others debate the merits of giving Synagis from 29 – 32 weeks and above, I wrote this as a reminder that not all populations are the same and therefore we should not paint all susceptible patients with one brush.

Micropreemie Lives Matter

Micropreemie Lives Matter

It seems the expression “(insert a group) lives matter” is present everywhere these days so I thought I would join in after a moving experience I had today.  For those of you who have been with the blog since the beginning you would have seen a number of posts that if you follow them in time, provide a glimpse into the transformation that Winnipeg has seen over the last year or so.

Prior to that point, 24 weeks was a cutoff for resuscitation that had been in place for some time and after a great amount of deliberation and thought was changed to 23 weeks.  This did not come without a great deal of angst and a tremendous amount of education and teamwork that our nurse educators and clinical leads were so instrumental in helping to role out.  The experience was outlined in a couple of posts that you may find interesting if you didn’t catch them the first time.  The first was Winnipeg hospital now resuscitating all infants at 22 weeks! A media led case of broken telephone. and the second being Winnipeg Hospital About to Start Resuscitating Infants at 23 weeks!

Since these two posts we have certainly had our fair share of experience as we have seen far more babies than anticipated but the region has met the challenge head on and although the numbers are small we appear to have not only more survivors than expected but all but one infant had gone home without O2 and all have been demand feeding at discharge.  While we await the 18 month outcomes, the results thus far appear reassuring.

A Special & Memorable Visit

Then today, a visit occurred from the first of such infants who is now just over a year of age.  He was bright eyed, smiling, interactive and by his parent’s account, has normal tone and assessments thus far by physiotherapy.  His presence in the NICU put smiles on faces and at least for myself made me think of the expression “Micropreemie Lives Matter”.  He was a baby that everyone predicted would not survive and then when he did, that he would be grossly developmentally impaired which he does not appear to be in the least.  His presence in the unit no doubt gives everyone who doubted the merits of moving down this path reason to pause.

Before you accuse me of wearing rose coloured glasses, make no mistake I know that he will not represent the outcome for everyone.  In fact at one of our hospitals two of such infants have died while we await the 18 month outcomes for the other survivors.  What his presence does though, is remind us or at least me that good outcomes are possible and in the case of our experience in Winnipeg may be more common that we thought they would be.

Black Swans and Human Nature

When I have spoken to audiences about the path forward when resuscitating such ELGANS I have often commented on the “Black Swan” effect.  blackswanThis was very nicely described by Nassim Taleb and described the human trait to react to unusual events with extreme reactions.  An example is no one wanting to fly in the months after the world trade centre bombing when statistically this may have been the safest period in history to fly.  Similarly, we as a team need to avoid the extreme reaction of saying that we should not be resuscitating such small infants when a bad outcome occurs.  As I have told many people, we know these patients will not all survive, we know a significant number will have adverse development yet not all will and at least in our small sample thus far the babies would appear to be doing better overall than anticipated.  If we know that bad outcomes will occur then why do we hear the questions come when they do such as “why are we doing this?”, “maybe we should rethink our position on 23 week infants”.  It happens because we care and we hate seeing families and their babies go through such painful experiences.  What we cannot do though for the sake of those such as our visitor today is react with a “Black Swan” reaction and steer the ship so to speak in the previous direction we were in.  There are survivors and they may do well and that is why I say “Micropreemie Lives Matter”.

In the paper by Rysavy the overall finding at 23 weeks was that 1 out of 6 would survive without moderate or severe disability.  What do we do as we increase our experience if the trend bears out that our outcomes are better?  How will we counsel families? Will we continue to use the statistics from the paper or quote our own despite us being a medium sized centre?

The Big Questions

As our experience with such infants increases we will also no doubt see a change in our thoughts about infants at 24 weeks.  I have seen this first hand already with a physician commenting today that 24 weeks is not such a big deal now!  This brings me to the big question (which I will credit a nurse I work with for planting in my head in the last two weeks) which is for another time to answer as this post gets a little lengthy but is something to ponder.  As our outcomes for 23 weeks improve and so do our results at 24 weeks (which is bound to happen with the more frequent team work in such situations) will our approach to infants at 24 weeks change.  In our institution we generally follow the CPS guidelines for the management of infants at extremely low GA and offer the choice of resuscitation at 24 weeks.  As outcomes improve at this GA will we continue to do so or will we reach a threshold where much like the case at 25 weeks we inform families that we will resuscitate their infant without providing the option of compassionate care?

It is too early to answer these questions conclusively but they are very deserving of some thought.  Lastly, I would like to thank the parent who came by today for inspiring me and to all those who will follow afterwards.

 

Do we need so many shots to prevent RSV bronchiolitis?

Do we need so many shots to prevent RSV bronchiolitis?

I have been a huge advocate of RSV prophylaxis since my days as a Pediatric resident. When I started my residency we were not using Palivizumab (Synagis) and I recall admitting 10+ patients per day at times with bronchiolitis.  With the use of passive immunization this rate dropped dramatically in Manitoba although rates in other areas of the country may have not seen such significant impacts.  Manitoba may be somewhat different from many areas due to the communities in Nunavut being so impacted when RSV enters these areas and can infect many of the children due to crowded living conditions and inability to really isolate kids from one and other.  The lack of benefit in other areas though, has no doubt led to controversy among practitioners who often wonder if giving 5 IM injections during the RSV season is indeed worth it.  The real question has not necessarily been does it work but to whom should it be given so that you get the most benefit.

A Big Change in The Last Year

In 2015 the CPS published a revised statement entitled Preventing hospitalizations for respiratory syncytial virus infection.  This statement has caused a great deal of controversy at least among those I have spoken with due to its significant departure from the previous recommendations. As per the statement:

  • In preterm infants without CLD born before 30 + 0 weeks’ GA who are <6 months of age at the start of RSV season, it is reasonable (but not essential) to offer palivizumab. Infants born after 30 + 0 weeks’ GA have RSV admission rates that are consistently ≤7% (Figure 3), yielding a minimum number needed to treat of 18 (90 doses of palivizumab to prevent one RSV admission) if one assumes 80% efficacy and five doses per infant. Therefore, palivizumab should not be prescribed for this group.

Gone are recommendations for treating those from 30 – 32 weeks and moreover 33- 35 weeks if meeting certain conditions.  There is a provision for those in Northern communities to expand these criteria to 36 0/7 weeks if such infants would require medical transport to receive care for bronchiolitis.  What is not really clear though is what is meant by Northern communities in terms of criteria to determine suitability exactly. Incidentally, the criteria are not so different than the AAP statement from August 2014.

Do We Need So Many Shots?

Just at the end of 2016 though Lavoie P et al in Vancouver, BC published a letter outlining their experience with a modified schedule of either 3 or 4 doses of palivizumab during the RSV season.  Included in the letter are their criteria for determining the number of doses and importantly pharmacokinetic data demonstrating the effectiveness of such schedules in achieving protective titres.  pharmacokineticsThe 3 dose schedule was used for those infants born between 29 0/7 and 35 weeks gestational age who had a risk factor score of 42 or more. Interestingly at the end of the RSV season, depriving such infants of 1 or 2 doses did not appear to impair the ability of the infant to maintain protective levels.

From a clinical standpoint the outcome data during this period examining 514 (3 dose) and 666 (4 dose) patients similarly suggests that they were indeed protected from disease.  In the 3 dose cohort only 1 patient was hospitalized with RSV during the dosing period and 1 infant afterwards.  In the 4 dose group, 10 were hospitalized with RSV  during the dosing schedule and a set of twins afterwards.  Aside from these known RSV infections, an additional 7 and 18 patients were hospitalized with bronchiolitis without viral identification during the dosing schedule with no cases of bronchiolitis afterwards.  Taken altogether and assuming that all cases were indeed RSV bronchiolitis the authors conclude that the overall rates are no different than those seen with a 5 dose schedule.

Is Something Rotten In The State of Denmark?

There is something peculiar here though.  There is no doubt that palivizumab must have gone through rigorous pharmacokinetic testing in order to determine the correct number of doses needed. For a 3-4 dose regimen to provide the same coverage in terms of antibody titres seems strange to me. I would love to believe the data but there is a skeptic in me. Secondly with respect to counting hospital admissions is this exhaustive in terms of including all hospitalization a in BC or at only some sites? Clarity is needed before considering such changes to practice.  Strangely it has been several months since this experience was published and there has been no discussion of it at least locally.*  Something as dramatic as this should have sparked some discussion and the absence of such leaves me questioning what am I missing?
From the standpoint of reducing interventions and pain in the neonate I am intrigued by these findings.  Parents as well would no doubt be happier with 3-4 IM injections over 5.  The additional benefit is no doubt financial as this product while effective does carry a significant cost per dose.  As you can see I have my doubts about the reproducibility of the results but it does at least offer some centres that have not been as enthusiastic about palivizumab something to consider. For some, the BC approach just might be the right thing.

  • I indicate that there has been little discussion locally of the article discussed.  There has indeed been discussion both here and in other Canadian provinces.  What I meant by that comment is that among my colleagues in Neonatology and Infectious Diseases and housestaff I have had only one discussion.