Cleminson and co-authors are to be commended for their excellent and
comprehensive work, which raises awareness to an important health
issue(1). Breastfeeding has undoubted benefits. However, it is important
to recognise, when promoting the health benefits, of breastfeeding that
breastmilk has very low levels of vitamin D (20IU or
0.5micrograms/litre)(2,3). This places infants, who are exclusively
breastfed, at risk of...
Cleminson and co-authors are to be commended for their excellent and
comprehensive work, which raises awareness to an important health
issue(1). Breastfeeding has undoubted benefits. However, it is important
to recognise, when promoting the health benefits, of breastfeeding that
breastmilk has very low levels of vitamin D (20IU or
0.5micrograms/litre)(2,3). This places infants, who are exclusively
breastfed, at risk of vitamin D deficiency and even rickets. The World
Health Organisation (WHO) recommends that infants be exclusively breastfed
in their first six months. However this would not satisfy a child's daily
vitamin D requirements. Such an infant would receive less than a tenth of
the daily 8.5micrograms recommended by the Department of Health (DoH) for
infants aged 0-6months(3); and required for normal growth(4).
The majority of vitamin D originates from dermal photosynthesis, in
Europe and the USA (5). At latitudes greater than 33 degrees North, there
is insufficient sunlight to generate adequate vitamin D in the winter
months. In Edmonton, Canada (52 degrees North) and Newcastle, UK (54
degrees North); vitamin D dermal photosynthesis is not possible for six
months of the year(6). The magnitude of the problem cannot be overstated.
Hospitalisation for rickets, for those under 15 years, has increased five-
fold in the UK between 1990 and 2011(7). According to the UK National Diet
and Nutrition Survey, 25% of the UK population are vitamin D deficient (25
-hydroxyvitamin D<25nmol/l)(8).
The DoH 2012, NICE 2008/2014 and Scientific Advisory Committee on
Nutrition 2007 guidance recommend that all pregnant and lactating mothers
receive a daily supplement containing 10micrograms of vitamin D
(8,9,10,11). They also advocate that all children from 6 months to 5years
receive vitamin D supplements. However, vitamin D supplementation is
indicated from birth for infants, if the mother did not receive vitamin D
supplements during pregnancy or if they belong to at-risk groups. This
includes those with dark skin types and/or with little sunlight exposure.
UNICEF explicitly supports this NICE guidance within the Baby
Friendly Initiative(12). The US Centre for Disease Control (CDC), for
their part, recommend 400IU daily vitamin D supplementation for all
breastfed infants, from birth(13,14). UNICEF, NICE, DoH and CDC emphasise
the importance of educating mothers and healthcare professionals on the
vital role of supplementary vitamin D for mothers and infants during
lactation. This important message must be promulgated along with the
health benefits of breastfeeding.
1. Cleminson J, Oddie S, Renfrew MJ, McGuire W. Being baby
friendly: evidence-based breastfeeding support. Arch Dis Child Fetal
Neonatal Ed. 2014 Oct 7. pii: fetalneonatal-2013-304873. doi:
10.1136/archdischild-2013 -304873.
2. Vitamin D deficiency Holick NEJM 2007; 357:266-81
4. Jeans PC, Stearns G. Effectiveness of vitamin D in infancy in
relation to the vitamin source. Proc Soc Exp Biol Med 1934; 31:1159-61
5. Braegger C, Campoy C, Colomb V, Decsi T, Domellof M, Fewtrell
M, Hojsak I, Mihatsch W, Molgaard C, Shamir R, Turck D, van Goudoever J;
on Behalf of the ESPGHAN Committee on Nutrition.Vitamin D in the Healthy
European Paediatric Population. J Pediatr Gastroenterol Nutr. 2013;56:692-
701
6. Wacker M, Holick MF. Sunlight and Vitamin D: A global
perspective for health. Dermatoendocrinol. 2013; 5:51-108
7. Goldacre M, Hall N, Yeates DG. Hospitalisation for children
with rickets in England: a historical perspective. Lancet. 2014; 383: 597-
8
We are grateful to Dr Ehrhardt for his response to our recent
paper.(1) It is certainly true that the populations compared are indeed
very different, which generally makes any such comparison fraught with
potential problems in interpretation. However, we would respectfully
point out that we made some allowance for this in our analysis of place of
booking and outcomes. This quite clearly shows adva...
We are grateful to Dr Ehrhardt for his response to our recent
paper.(1) It is certainly true that the populations compared are indeed
very different, which generally makes any such comparison fraught with
potential problems in interpretation. However, we would respectfully
point out that we made some allowance for this in our analysis of place of
booking and outcomes. This quite clearly shows advantage to women booking
in Level 3 Services, compared to those booking in Level 2 services whether
or not they were transferred (aOR: 0.79 (0.63; 0.98)).
In a related paper using more recent national data and instrumental
variables using the nearest hospital to the mother's residence to describe
the base populations, we also come to the same conclusion for this group
of extremely preterm births.(2)
Although not perfect corrections for a complex situation these two
findings provide some reassurance that our conclusions are valid.
Yours sincerely
Neil Marlow
1. Marlow N, Bennett C, Draper ES, et al. Perinatal outcomes for
extremely preterm babies in relation to place of birth in England: The
EPICure 2 Study. Archives of Disease in Childhood Fetal and Neonatal
Edition 2014;99:F181-8
2. Watson SI, Arulampalam W, Petrou S, et al. The effects of
designation and volume of neonatal care on mortality and morbidity
outcomes of very preterm infants in England: retrospective population-
based cohort study. BMJ Open 2014;4(7):e004856.
Thank you for your response to our research "Non-invasive
measurements of ductus arteriosus flow directly after birth".
We agree with Dr. Hutchon that a caesarian section can influence the
respiratory transition of a newborn infant. As such, our results reflect
the transition after elective caesarian section with cord clamping within
1 minute after birth, which...
Thank you for your response to our research "Non-invasive
measurements of ductus arteriosus flow directly after birth".
We agree with Dr. Hutchon that a caesarian section can influence the
respiratory transition of a newborn infant. As such, our results reflect
the transition after elective caesarian section with cord clamping within
1 minute after birth, which we have indicated is a limitation of our study
as stated in the Discussion section of our manuscript. However, as cord
clamping was delayed between 30-60 s after birth, most newborns will have
commenced breathing before the cord was clamped. While many guidelines
suggest a fixed time interval of 1-3 minutes between birth and cord
clamping, this is not physiological and is only relevant to individual
infants because most infants will have commenced breathing within this
time. We agree that infants that did not started breathing sufficiently
before cord clamping could have had a less efficient transition, but our
small sample size prohibits a more detailed subgroup analysis. However, as
all of these infants had a normal "clinical" transition and did not
require respiratory support or any other specialized medical care, we feel
that the potential influence of cord clamping before the start of
breathing had no significant clinical impact. With regard to the WHO
advice, the observations from Bhatt et al. show that the timing of cord
clamping is probably less important than the occurrence of breathing
before the cord is clamped.(1)
It would be interesting to compare the transition of neonates after
vaginal delivery to our results. However, no data within the first 10
minutes after vaginal delivery is present as our report is the first to
assess hemodynamic changes during this time frame. This study may
therefore be regarded as a starting point for future research on
hemodynamic changes directly after birth.
As we have described in a previous publication, aeration of the lung
and the consequent rise in preload is most likely responsible for the
increase in left ventricular output (LVO).(2) The increase in preload will
cause a pressure gradient to exist over the Ductus Arteriosus (DA) and
foramen ovale (FO). As Dr. Hutchon suggests the resulting shunt over the
FO could explain differences between LVO and right ventricular output
(RVO). However, we must stress that the simple mathematical calculation of
adding or subtracting mean blood flows and outputs from a group of
infants, which were measured using echocardiography at different time
points is not a legitimate way of making comparisons. The values stated in
our manuscript are mean values and although they were all measured within
a small time range, it is not possible to make these measurements
simultaneously. As these parameters are very dynamic and change over time,
ideally they should be measured simultaneously and comparisons should be
made in individual infants rather between groups means. Furthermore,
Doppler derived measurements of absolute volume are based on several
assumptions and cardiac output can range from 150 ml/kg/min to 273
ml/kg/min for LVO and from 200 to 310 ml/kg/min for RVO in term neonates
depending on the site of measurement, the vascular diameter and Doppler
method used.(3) As such we believe that the calculation of shunting across
the FO as done by Dr. Hutchon is based on too many assumptions for any
valid conclusions to be drawn. We consider that our figures are neither an
anomaly nor a sign of a disrupted transitional circulation, but merely
reflect the suboptimal assessment of absolute volumes with
echocardiography.
This is the main reason that we did not focus on the absolute
differences between LVO and RVO at the described time points. Instead we
used the Doppler derived measurements to assess differences over time
during the first 10 minutes after birth in LVO, RVO and blood flow shunt
over the DA. Furthermore, we calculated the ratio between DA right-to-left
vs. left-to-right flow based on the velocity time integral of the flow
patterns. As this is a dimensionless parameter that is not influenced by
assumptions or inaccuracies in the measurement of vessel diameter, it is
more appropriate to use for investigations into the hemodynamic
transition.
The matter of whether left-to-right shunting across the FO is a
normal physiological process is an interesting point and one that hasn't
really been addressed previously, mostly because it was previously
considered to be a one way valve. Nevertheless, as the two ventricles act
as two independent pumps working at different outputs throughout fetal
life, we consider that it is unrealistic to expect that the ventricles
will immediately synchronize their outputs at birth. Instead we believe
that there will be a period of adjustment during the immediate newborn
period and theoretically bidirectional flows in both the FO and the DA
would allow both ventricular outputs to come into balance without
triggering systemic hypotension or pulmonary hypertension.
References
(1) Bhatt S, Alison BJ, Wallace EM, Crossley KJ, Gill AW, Kluckow M,
et al. Delaying cord clamping until ventilation onset improves
cardiovascular function at birth in preterm lambs. J Physiol 2013;591:2113
-26.
(2) van Vonderen JJ, Roest AA, Siew ML, Blom NA, van Lith JM, Walther
FJ, et al. Noninvasive measurements of hemodynamic transition directly
after birth. Pediatr Res 2014;75:448-52.
(3) de Waal KA. The methodology of Doppler-derived central blood flow
measurements in newborn infants. Int J Pediatr 2012;2012:680162.
We are sorry to hear that colleagues at the Royal Free Hospital felt
that our analysis of the data they provided did not reflect the realities
of what is happening in their neonatal unit.
We have already made significant changes to the processes for the
2013 data, which is expected to be published this October. NNAP now
includes entries in either of the locations within the badger system
("daily data" or "ad h...
We are sorry to hear that colleagues at the Royal Free Hospital felt
that our analysis of the data they provided did not reflect the realities
of what is happening in their neonatal unit.
We have already made significant changes to the processes for the
2013 data, which is expected to be published this October. NNAP now
includes entries in either of the locations within the badger system
("daily data" or "ad hoc forms") as indicating that an ROP screen took
place. Furthermore, we have worked with the software supplier so that
within the current version of the software an entry in the daily data to
indicate that an ROP screen took place now automatically opens an ad hoc
form, where the rest of the details of the ROP screen can be entered.
We hope that these measures, and others such as the inclusion of post
discharge ROP screens conducted at the correct time, will help NNAP and
its participant units to highlight good practice, as well as identifying
any units where adherence to national guidance is not yet complete.
We also agree that training users in data entry, ensuring staff
understand the significance of data entry and reviewing data prior to its
use for national audit, is crucial for the audit to be effective.
Finally, it is good to hear that the unit is reviewing its processes
in response to the NNAP findings, as the main aim of the audit is to
ensure best practice is shared to improve care for newborns.
The letter by Neil Finer and others raises important questions around
quality and completeness of data used for national benchmarking.
The authors criticise the quality of NNAP data used in the published
2012 report. They show in one unit where there were inaccuracies due to
data not being entered into the Badger system. They give examples of how
the Badger system possibly contributed to the problem by not aler...
The letter by Neil Finer and others raises important questions around
quality and completeness of data used for national benchmarking.
The authors criticise the quality of NNAP data used in the published
2012 report. They show in one unit where there were inaccuracies due to
data not being entered into the Badger system. They give examples of how
the Badger system possibly contributed to the problem by not alerting
users adequately to missing data.
The NNAP project gives the neonatal community in UK a unique
opportunity to analyse whole population data. I hope these reported
problems with NNAP data are not seen as a reason to stop national audit
and benchmarking but as a reminder of the need to take seriously the
collection of better data. It is inevitably an iterative process and NNAP
is continuing to evolve and improve. The neonatal community must continue
to support the very important role of a national benchmarking project.
The requirements of NNAP are published and units should have in place
systems to ensure timely collection of important data.
Clevermed is committed to working with users, and with NNAP, to
assist in the collection of data that are complete and of good quality, as
well ensuring timely and correct downloads.
Since 2012 the 'idiosyncrasies' referred to in the letter have
already been addressed within the new version of the software (BadgerNet)
and further improvements are due for release. There are also many more
lists, dashboards and reports that help users check the quality and
completeness of their data. I believe that the quality and completeness
of ROP screening data within the system has already improved significantly
since 2012.
More than 80% of units have changed (at no charge) to the new version
of the software and Clevermed aims to complete the migration by the end of
2014 when the older Badger 3 will no longer be supported.
Conflict of Interest:
Dr Andrew Lyon works with, and receives payment from, Clevermed Ltd.
We read with interest the article by Rolland et al regarding a
retrospective natural history study of the PDA in a cohort of preterm
infants in a unit which conservatively managed the presence of a PDA after
24 hours(1). We have concerns about the data analysis and the conclusions
drawn. In particular we question the decision to exclude infants who died
within the first 72 hrs and the subsequent exclusion of infants who d...
We read with interest the article by Rolland et al regarding a
retrospective natural history study of the PDA in a cohort of preterm
infants in a unit which conservatively managed the presence of a PDA after
24 hours(1). We have concerns about the data analysis and the conclusions
drawn. In particular we question the decision to exclude infants who died
within the first 72 hrs and the subsequent exclusion of infants who died,
due to inability to determine the date of PDA closure. Out of the total
cohort (103 infants) 12 died and were excluded in the first 72 hrs and a
further 13 subsequently died and were excluded meaning that almost 25% of
the cohort died without having their ductal status documented. As the
authors themselves acknowledge, a significant number of these infants died
from complications that may be related to a PDA, including pulmonary
haemorrhage, intraventricular haemorrhage, unresponsive respiratory or
multisystem failure and NEC. It is misleading to exclude these from the
natural history cohort and this approach by other authors in the past has
led to a potential misrepresentation of the harm that may occur as a
result of a persisting DA. There are several published natural history
series showing significant and strong associations with morbidity and
mortality if all-cause mortality is left in the cohort for analysis
purposes(2,3). Of the total group of 103 infants in this study only 59
(57%) have certain documentation of ductal closure. The balance of 44
infants either died (26 infants) or did not have spontaneous closure
documented using the gold standard of an echocardiogram. 7 infants had a
persisting PDA at discharge which is of itself not a benign outcome with
potential for increased mortality in the first year(2) and a possible
requirement for surgical closure. If it is assumed that all of the
unaccounted for patients had a PDA, the spontaneous closure rate is
actually only 57% - 16% lower than that reported in the conclusion of this
paper of 73%.
The premise of Rolland et al is that early ductal shunting is not
important, whereas work by our group suggests that the first 24-48 hours
may be the most important time for ductal related morbidity. Lack of early
assessment of the hemodynamic effects of a PDA in the first 72 hrs of life
often results in failure to recognise the association between early PDA
and morbidity/mortality. There is clear benefit to early/prophylactic
treatment of a significant PDA including reduced pulmonary haemorrhage and
intraventricular haemorrhage(4). We have recently published a trial of
targeted early treatment vs placebo demonstrating reduction in pulmonary
haemorrhage and reduced later treatment of PDA(5). Benefits from later
treatment after 3 days are less clear and as identified by many authors
should be the subject of well performed RCT's. Performing a cohort study
and excluding infants who have uncertain ductal status and suffer an
adverse outcome is problematic. An alternative conclusion to the data
presented is that a significant number of infants in this cohort died from
potential duct related complications such as pulmonary haemorrhage and
that earlier identification and treatment may have avoided this.
Concluding from the data presented that the exposure to the risk of
therapeutic intervention to close a PDA is not warranted based on
spontaneous closure rates of a selected surviving sub-group is not
justified.
References:
1] Rolland A, Shankar-Aguilera S, Diomand? D et al. Arch Dis Child Fetal
Neonatal Ed
Published Online First: 28 August 2014 doi:10.1136/archdischild-2014-
306339
2] Noori S. McCoy M. Friedlich P et al. Failure of ductus arteriosus
closure is associated with increased mortality in preterm infants.
Pediatrics 2009;123(1):e138-44.
3] Sellmer A, Vandborg Bjerre J,T+Rahbek Schmidt M et al. Morbidity and
mortality in preterm neonates with patent ductus arteriosus on day 3. Arch
Dis Child Fetal Neonatal Ed 2013 Nov;98(6):F505-10.
4] Fowlie PW, Davis PG, McGuire W. Prophylactic intravenous indomethacin
for preventing mortality and morbidity in preterm infants.[Update of
Cochrane Database Syst Rev. 2002;(3):CD000174; PMID: 12137607]. Cochrane
Database Syst Rev 2010;CD000174.
5] Kluckow M, Jeffery M, Gill A et al. A randomised placebo-controlled
trial of early treatment of the patent ductus arteriosus. Arch Dis Child
Fetal Neonatal Ed 2014;99:F99-F104.
We read with interest the recent publication by Motta and colleagues
(1). Their data pertaining to use of fresh frozen plasma (FFP) in the
neonatal intensive care unit are helpful.
The British Committee for Standards in Haematology transfusion
guidelines (2) suggest that any neonates with significant coagulopathy
[e.g. prothrombin time (PT)/activated partial thromboplastin time (APTT)
ratio >1.5] and signif...
We read with interest the recent publication by Motta and colleagues
(1). Their data pertaining to use of fresh frozen plasma (FFP) in the
neonatal intensive care unit are helpful.
The British Committee for Standards in Haematology transfusion
guidelines (2) suggest that any neonates with significant coagulopathy
[e.g. prothrombin time (PT)/activated partial thromboplastin time (APTT)
ratio >1.5] and significant risk of bleeding (e.g. preterm and/or
intubated, previous periventricular haemorrhage), FFP is indicated. We
believe that this practice may lead to over-transfusion of FFP.
We have recently published data pertaining to the extremely premature
neonatal population (n = 183) born < 27 weeks' gestation on day 1 of
life (3). In this large patient cohort, we observed similar clotting times
to those reported by Motto and co-workers(Table 3) (1) in their similar
but smaller patient population. In our cohort, median (range 25th-75th
percentile) prothrombin time (PT) and activated partial thromboplastin
time (APTT) values were 20.2 (17.8-24.1) and 67.4 (56.3-88.4) seconds,
respectively.
Unfortunately, timing of both cranial sonography and specific
laboratory assessments of haemostasis were not described by Motto et al
(1). Coagulation tests were performed pre FFP transfusion, only 42% of
which occurred in first 3 days of life, with remainder occurring at later
postnatal age. Most intraventricular haemorrhage occurs within first 72
hours of life. The timing of blood sampling may influence results of
coagulation parameters, as coagulation values change with gestational age
(4). The association/lack thereof between IVH and coagulation values is
difficult to establish given lack of clarity regarding timing of both
events.
We agree with the authors that FFP should be used cautiously given
paucity of evidence for effectiveness of these transfusions. Given that
extremely premature infants have median coagulation values > 1.5 ratio,
review of FFP transfusion guidelines is warranted, as many additional
infants may have had FFP without good indication.
(1)Department of Paediatrics, Rotunda Hospital, Dublin, Ireland
(2)Department of Haematology, Rotunda Hospital, Dublin, Ireland
References
1. Motta M, Del Vecchio A, Perrone B, Ghirardello S, Radicioni M.
Fresh frozen plasma use in the NICU: a prospective, observational,
multicentred study. Arch Dis Child Fetal Neonatal Ed. 2014 Mar 19. doi:
10.1136/archdischild-2013-304747. [Epub ahead of print]
2. Gibson BE, Todd A, Roberts I, Pamphilon D, Rodeck C, Bolton-Maggs
P, Burbin G, Duguid J, Boulton F, Cohen H, Smith N, McClelland DB, Rowley
M, Turner G; British Commitee for Standards in Haematology Transfusion
Task Force: Writing group. Transfusion guidelines for neonates and older
children. Br J Haematol. 2004 Feb;124(4):433-53.
3. Neary E, Okafor I, Al-Awaysheh F, et al. Laboratory coagulation
parameters in extremely premature infants born earlier than 27 gestational
weeks upon admission to a neonatal intensive care unit. Neonatology
2013;104:222-7.
4. Andrew M, Paes B, Milner R, et al. Development of the human
coagulation system in the healthy premature infant. Blood 1988;72:1651-7.
We congratulate the authors on this study of neonatal transitional
circulation performed so quickly after birth. The authors state that the
ductal flow ratio reported in their study reflects pulmonary and
haemodynamic transition and can be used to monitor neonatal transition in
healthy infants. The implication is that their study describes a
physiological transition in healthy term infants, but we que...
We congratulate the authors on this study of neonatal transitional
circulation performed so quickly after birth. The authors state that the
ductal flow ratio reported in their study reflects pulmonary and
haemodynamic transition and can be used to monitor neonatal transition in
healthy infants. The implication is that their study describes a
physiological transition in healthy term infants, but we question that
this is the case.
Delivery by elective caesarean section is not a physiological birth
but it does permit the neonate an atraumatic birth. We are particularly
concerned that the transition may have been disrupted by the timing of
cord clamping which was between 30 and 60 seconds. While this is
considered delayed cord clamping by some, most guidelines recommend a
minimum of 60 seconds have elapsed before the circulation is interrupted
by cord clamping. The WHO advises 3 minutes.(1) Not all of the babies in
the series had established respiration before clamping and cord clamping
before the onset of respiration has a marked effect on cardiac output.(2)
It is therefore questionable that the mean and range of results published
represents a normal transition in healthy infants.
The normal fetal circulation is well described with the two
ventricles pumping in parallel, the right ventricular output being
significantly more than the left and the flow across two shunts, right to
left in the ductus arteriousus and right to left across the foramen ovale.
The normal neonatal circulation is also well described with equal outputs
by both ventricles and closed shunts. A closer look at the results
suggest some anomalous flow not readily compatible with the end result of
the neonatal circulation. For example at ten minutes the mean right
ventricular output is 343 mls/kg/min and mean left ventricular output is
212 mls/kg/min and the DA flow is 8mls/kg/min left to right. (ratio R to
L =0.9). Where does the right ventricle get the 343 output as only 212 -
8 are reaching the systemic circulation and returning to the right atrium.
Also if the pulmonary blood flow is 343+8 = 351, the excess of 141 must
be spilling left to right across the foramen ovale. Reverse flow in the
foramen ovale is described but has not been quantified. We question that
these flows are evidence that this heart is now close to transitioning to
a parallel ventricular pattern with equal outputs. Reverse flow across the
foramen ovale of 141 is contributing to over 40% of the right ventricular
output. This blood has just been through the pulmonary circulation and is
oxygenated but is now returning to the right ventricle to be pumped
through the pulmonary circulaton once more. Such flow is completely
inefficient. Can the authors explain this anomaly in physiogical terms or
could this finding in fact be a demonstration that the early clamping at
under 60 seconds sometimes before the onset of respiration has indeed
disrupted the transitional circulation ?
Reference
1. World Health Organization (WHO), US Agency for International
Development (US AID), Maternal and Child Health Integrated Program
(MCHIP). (2013). Delayed cord clamping of the umbilical cord to reduce
infant anaemia. Updated 2013. Available from:
http://www.mchip.net/node/1562 (Accessed June 12, 2014).
2. Bhatt S, Alison BJ,Wallace EM, Crossley KJ, Gill AW, Kluckow M, et al.
Delaying cord clamping until
ventilation onset improves cardiovascular function at birth in preterm
lambs. J Physiol 2013 591(Pt
8): 2113-26.
We congratulate the authors on this study of neonatal transitional circulation performed so quickly after birth. The authors state that the ductal flow ratio reported in their study reflects pulmonary and haemodynamic transition and can be used to monitor neonatal transition in healthy infants. The implication is that their study describes a physiological transition in healthy term infants, but we question that this is the case.
Delivery by elective caesarean section is not a physiological birth but it does permit the neonate an atraumatic birth. We are particularly concerned that the transition may have been disrupted by the timing of cord clamping which was between 30 and 60 seconds. While this is considered delayed cord clamping by some, most guidelines recommend a minimum of 60 seconds have elapsed before the circulation is interrupted by cord clamping. The WHO advises 3 minutes.(1) Not all of the babies in the series had established respiration before clamping and cord clamping before the onset of respiration has a marked effect on cardiac output.(2) It is therefore questionable that the mean and range of results published represents a normal transition in healthy infants.
The normal fetal circulation is well described with the two ventricles pumping in parallel, the right ventricular output being significantly more than the left and the flow across two shunts, right to left in the ductus arteriousus and right to left across the foram...
We congratulate the authors on this study of neonatal transitional circulation performed so quickly after birth. The authors state that the ductal flow ratio reported in their study reflects pulmonary and haemodynamic transition and can be used to monitor neonatal transition in healthy infants. The implication is that their study describes a physiological transition in healthy term infants, but we question that this is the case.
Delivery by elective caesarean section is not a physiological birth but it does permit the neonate an atraumatic birth. We are particularly concerned that the transition may have been disrupted by the timing of cord clamping which was between 30 and 60 seconds. While this is considered delayed cord clamping by some, most guidelines recommend a minimum of 60 seconds have elapsed before the circulation is interrupted by cord clamping. The WHO advises 3 minutes.(1) Not all of the babies in the series had established respiration before clamping and cord clamping before the onset of respiration has a marked effect on cardiac output.(2) It is therefore questionable that the mean and range of results published represents a normal transition in healthy infants.
The normal fetal circulation is well described with the two ventricles pumping in parallel, the right ventricular output being significantly more than the left and the flow across two shunts, right to left in the ductus arteriousus and right to left across the foramen ovale. The normal neonatal circulation is also well described with equal outputs by both ventricles and closed shunts. A closer look at the results suggest some anomalous flow not readily compatible with the end result of the neonatal circulation. For example at ten minutes the mean right ventricular output is 343 mls/kg/min and mean left ventricular output is 212 mls/kg/min and the DA flow is 8mls/kg/min left to right. (ratio R to L =0.9). Where does the right ventricle get the 343 output as only 212 - 8 are reaching the systemic circulation and returning to the right atrium. Also if the pulmonary blood flow is 343+8 = 351, the excess of 141 must be spilling left to right across the foramen ovale. Reverse flow in the foramen ovale is described but has not been quantified. We question that these flows are evidence that this heart is now close to transitioning to a parallel ventricular pattern with equal outputs. Reverse flow across the foramen ovale of 141 is contributing to over 40% of the right ventricular output. This blood has just been through the pulmonary circulation and is oxygenated but is now returning to the right ventricle to be pumped through the pulmonary circulaton once more. Such flow is completely inefficient. Can the authors explain this anomaly in physiogical terms or could this finding in fact be a demonstration that the early clamping at under 60 seconds sometimes before the onset of respiration has indeed disrupted the transitional circulation ?
Reference 1. World Health Organization (WHO), US Agency for International Development (US AID), Maternal and Child Health Integrated Program (MCHIP). (2013). Delayed cord clamping of the umbilical cord to reduce infant anaemia. Updated 2013. Available from: http://www.mchip.net/node/1562 (Accessed June 12, 2014). 2. Bhatt S, Alison BJ,Wallace EM, Crossley KJ, Gill AW, Kluckow M, et al. Delaying cord clamping until ventilation onset improves cardiovascular function at birth in preterm lambs. J Physiol 2013 591(Pt 8): 2113-26.
Dear Editor
I would like to thank Dr's Madar and Kariholu for their interest in the
recent review article on use of ultrasound to assess the haemodynamic
status of the sick neonate(1,2). They raise an important point that
highlights the current disconnect between the recognition of the
usefulness of ultrasound in general for assessment of sick neonates and
the lack of availability of suitable training courses to learn th...
Dear Editor
I would like to thank Dr's Madar and Kariholu for their interest in the
recent review article on use of ultrasound to assess the haemodynamic
status of the sick neonate(1,2). They raise an important point that
highlights the current disconnect between the recognition of the
usefulness of ultrasound in general for assessment of sick neonates and
the lack of availability of suitable training courses to learn these
skills. They further propose that ultrasound is an essential skill for the
neonatologist and thus a training syllabus in neonatal functional cardiac
assessment should be developed, and foreshadow the incorporation of this
training into neonatal training programs.
Neonatology is not alone in this realisation and there is a steady push to
incorporate ultrasound to help guide clinical care into many specialty
training programs ranging from intensive care, accident and emergency to
surgery and renal medicine(3). Separation of the use of point of care
ultrasound to guide clinical care from a high level consultational
ultrasound to exclude structural pathology is key to gaining acceptance
for the use of ultrasound in this way. In Neonatology it is important to
avoid describing a focused clinical cardiac ultrasound as an
echocardiogram, as this is a term that is usually interpreted as meaning a
high level cardiology based examination, with different expectations and
outcomes. In Australia and New Zealand we have developed a point of care
ultrasound training program for both cardiac and cranial ultrasound(4).
The course has a basic and an advanced module and is based on the
following principles:
1] A physics and safety module
2] An initial introductory theory and hands on course
3] Self directed learning, logbooking and supervision of ultrasound in a
clinical neonatal setting
4] Logbook and competency assessment
5] Reaccreditation requirements
We have found that learning neonatal ultrasound in this "apprenticeship"
setting, similar to that of learning neonatology generally, results in
clinicians who have a clear understanding of the uses and limitations of
ultrasound use in the NICU. Contrary to concerns raised by traditional
users of ultrasound in the neonatal unit, we have found that not only is
physiological management of the sick neonate made easier, but that
significant structural cardiac defects are often identified earlier in the
neonatal course than had been the case before the increased use of
ultrasound to guide clinical care. We have not as yet mandated this
training as part of the national neonatal training program, mainly because
we are unable to guarantee access to training to all trainees. This will
change as the critical mass of neonatologists using ultrasound increases.
I encourage Dr's Madar and Kariholu to engage with colleagues interested
in developing a neonatal ultrasound training program in the United Kingdom
and make it a reality.
(1).Kluckow M Use of ultrasound in the haemodynamic asessment of the
sick neonate. Arch. Dis. Child. Fetal Neonatal Ed. 2014 99:F332-F337;
doi:10.1136/archdischild-2013-304926
(2). John Madar, Ujwal Kariholu. Cardiac assessment using echocardiography
in the sick neonate - An unmet need for a training syllabus for aspiring
neonatologists.Arch. Dis. Child. Fetal Neonatal Ed. 2014
(3). Moore CL and Copel JA. Point of care ultrasonography. N Engl J Med.
2011 Feb 24;364(8):749-57
(4). http://www.asum.com.au/newsite/Education.php?p=CCPU-Neonatal
Cleminson and co-authors are to be commended for their excellent and comprehensive work, which raises awareness to an important health issue(1). Breastfeeding has undoubted benefits. However, it is important to recognise, when promoting the health benefits, of breastfeeding that breastmilk has very low levels of vitamin D (20IU or 0.5micrograms/litre)(2,3). This places infants, who are exclusively breastfed, at risk of...
Dear Editor
We are grateful to Dr Ehrhardt for his response to our recent paper.(1) It is certainly true that the populations compared are indeed very different, which generally makes any such comparison fraught with potential problems in interpretation. However, we would respectfully point out that we made some allowance for this in our analysis of place of booking and outcomes. This quite clearly shows adva...
Response to "Physiological transition ?"
Thank you for your response to our research "Non-invasive measurements of ductus arteriosus flow directly after birth".
We agree with Dr. Hutchon that a caesarian section can influence the respiratory transition of a newborn infant. As such, our results reflect the transition after elective caesarian section with cord clamping within 1 minute after birth, which...
We are sorry to hear that colleagues at the Royal Free Hospital felt that our analysis of the data they provided did not reflect the realities of what is happening in their neonatal unit.
We have already made significant changes to the processes for the 2013 data, which is expected to be published this October. NNAP now includes entries in either of the locations within the badger system ("daily data" or "ad h...
The letter by Neil Finer and others raises important questions around quality and completeness of data used for national benchmarking.
The authors criticise the quality of NNAP data used in the published 2012 report. They show in one unit where there were inaccuracies due to data not being entered into the Badger system. They give examples of how the Badger system possibly contributed to the problem by not aler...
We read with interest the article by Rolland et al regarding a retrospective natural history study of the PDA in a cohort of preterm infants in a unit which conservatively managed the presence of a PDA after 24 hours(1). We have concerns about the data analysis and the conclusions drawn. In particular we question the decision to exclude infants who died within the first 72 hrs and the subsequent exclusion of infants who d...
We read with interest the recent publication by Motta and colleagues (1). Their data pertaining to use of fresh frozen plasma (FFP) in the neonatal intensive care unit are helpful.
The British Committee for Standards in Haematology transfusion guidelines (2) suggest that any neonates with significant coagulopathy [e.g. prothrombin time (PT)/activated partial thromboplastin time (APTT) ratio >1.5] and signif...
Dear Sir,
We congratulate the authors on this study of neonatal transitional circulation performed so quickly after birth. The authors state that the ductal flow ratio reported in their study reflects pulmonary and haemodynamic transition and can be used to monitor neonatal transition in healthy infants. The implication is that their study describes a physiological transition in healthy term infants, but we que...
Dear Sir,
We congratulate the authors on this study of neonatal transitional circulation performed so quickly after birth. The authors state that the ductal flow ratio reported in their study reflects pulmonary and haemodynamic transition and can be used to monitor neonatal transition in healthy infants. The implication is that their study describes a physiological transition in healthy term infants, but we question that this is the case.
Delivery by elective caesarean section is not a physiological birth but it does permit the neonate an atraumatic birth. We are particularly concerned that the transition may have been disrupted by the timing of cord clamping which was between 30 and 60 seconds. While this is considered delayed cord clamping by some, most guidelines recommend a minimum of 60 seconds have elapsed before the circulation is interrupted by cord clamping. The WHO advises 3 minutes.(1) Not all of the babies in the series had established respiration before clamping and cord clamping before the onset of respiration has a marked effect on cardiac output.(2) It is therefore questionable that the mean and range of results published represents a normal transition in healthy infants.
The normal fetal circulation is well described with the two ventricles pumping in parallel, the right ventricular output being significantly more than the left and the flow across two shunts, right to left in the ductus arteriousus and right to left across the foram...
Show MoreDear Editor I would like to thank Dr's Madar and Kariholu for their interest in the recent review article on use of ultrasound to assess the haemodynamic status of the sick neonate(1,2). They raise an important point that highlights the current disconnect between the recognition of the usefulness of ultrasound in general for assessment of sick neonates and the lack of availability of suitable training courses to learn th...
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