Harding et al state that the problem of hypernatraemic dehydration in
breastfed babies is attributable to: "the reluctance of midwives to weigh
breastfed infants". They imply that weighing between 72 and 96 hours would
be an effective intervention, but provide no evidence to support this
claim.
It does not surprise me that the views of midwives and consultant
neonatologists differ on this point. Whe...
Harding et al state that the problem of hypernatraemic dehydration in
breastfed babies is attributable to: "the reluctance of midwives to weigh
breastfed infants". They imply that weighing between 72 and 96 hours would
be an effective intervention, but provide no evidence to support this
claim.
It does not surprise me that the views of midwives and consultant
neonatologists differ on this point. Whereas midwives in this country
receive specific training in the management of breastfeeding, most
paediatricians do not. Indeed most are (to coin a political aphorism) "one
club golfers" where the assessment of breastfeeding is concerned: weighing
might be one indicator of a baby’s fluid balance but there are other ways
of assessing the adequacy of breastfeeding, including feed observation.
Given these differences in expertise one might reasonably ask which group
of professionals gave the correct answer!
As Harding et al point out "normal weight loss is at its maximum"
between 72-96 hours after birth. In many midwives’ view (and mine) this
constitutes the strongest argument against weighing a baby who has been
observed to feed well. Demonstrating this weight loss frequently
undermines breastfeeding no matter how carefully the physiology of the
phenomenon is explained. Additionally (particularly in primiparous
mothers) lactogenesis is only just becoming established between 48 and 72
hours. Thus the volume of milk transferred to the infant is still rising
sharply between 72 and 96 hours of age.
Before early weighing can be recommended as a screening test for
hypernatraemic dehydration more information is required. Firstly the
precision of weighing in practice and the accuracy of measured differences
need clarification. In relation to this the predictive value of a weight
change on day 3–4 needs to be ascertained. Secondly the comparative
merits of other methods of assessing breastfeeding need more emphasis (the
American Academy of Pediatrics consensus statement cited by the authors
views weighing as only one aspect of the assessment). Thirdly the nature,
effectiveness and cost of resulting interventions need to be considered
(more than "encouragement to continue" may be needed). Finally the
potential adverse consequences of weighing (alluded to above) need to be
set against any diagnostic benefit.
In summary I fully agree that the prevention of hypernatraemic
dehydration is important but am not persuaded that early weighing is the
answer. In my view better training of health professionals, including
paediatricians, in the management of breastfeeding would go further.
We thank Dr Cliona Ni Bhrolchain for her interest in our study [1] and
for the points she raises, but we disagree with her interpretation.
She is correct in noting that the referrals for eye and cardiac
abnormalities were routed through senior paediatricians, but wrong to
conclude that this would invalidate the results. The same individuals at
each hospital performed this senior review, an...
We thank Dr Cliona Ni Bhrolchain for her interest in our study [1] and
for the points she raises, but we disagree with her interpretation.
She is correct in noting that the referrals for eye and cardiac
abnormalities were routed through senior paediatricians, but wrong to
conclude that this would invalidate the results. The same individuals at
each hospital performed this senior review, and in any case such a
"filter" would not affect the sensitivity of the screening [2], as this is
dependent purely on the rate of abnormalities detected by the primary
examiners. As we state in our discussion, the calculated positive
predictive values may indeed have been improved for both SHOs and ANNPs,
but there is no reason to suspect any selective bias.
In terms of infants failing to attend at the specialist clinics,
validation of our data was performed demonstrating that even if it were
assumed firstly that all such infants were normal, and then secondly that
all such infants had abnormalities, the significance of our findings would
not be affected.
We originally hypothesised that ANNPs are as effective as trainee
paediatricians at detecting hip, eye, and cardiac abnormalities during the
neonatal examination. This we demonstrated, furthermore we found that
ANNPs are more effective in detecting hip and eye abnormalities. Thus we
conclude that in this regard the case for ANNPs is proven.
Tim Lee
Department of Paediatrics,
St James's University Hospital,
Leeds LS9 7TF, UK
Ruth Skelton
Department of Paediatrics,
The General Infirmary at Leeds,
Leeds LS2 9DE, UK
Caryl Skene
Department of Paediatrics,
Hull and East Yorkshire Hospitals NHS Trust,
Anlaby Road,
Hull HU3 2JZ, UK
References
(1) Lee TWR, Skelton RE, Skene C. Routine neonatal examination -
Effectiveness of trainee paediatrician compared to advanced neonatal nurse
practitioner. Arch Dis Child Fetal Neonatal Ed 2001; 85: F100-F104.
(2) Gilbert R, Logan S. Assessing diagnostic and screening tests. In:
Evidenced based paediatrics and child health, edited by Moyer VA, Elliot
EJ, Davis RL et al. BMJ Books 2000; P24-36.
The debate regarding placement of central venous catheter
tips in neonates leaves me puzzled. We have been using percutaneously
placed central venous catheters in our unit since 1978, with the aim of
tip placement to be in the right atrium achieved in approximately 70% of
catheters. I have prospectively maintained records of every baby, their
diagnoses, managements (including central venous cathete...
The debate regarding placement of central venous catheter
tips in neonates leaves me puzzled. We have been using percutaneously
placed central venous catheters in our unit since 1978, with the aim of
tip placement to be in the right atrium achieved in approximately 70% of
catheters. I have prospectively maintained records of every baby, their
diagnoses, managements (including central venous catheter use) and
complications treated here since 1983. These records encompass more than
2000 catheters (the exact number needs to be reconstructed from some paper
records soon) placed in 1687 babies, for a total of 31867 catheter-days up
until 30/06/2001. The longest life of any single catheter has been 99
days. I have never seen the complication of cardiac tamponade from one of
these catheters. Why? Some may suggest we have 'missed' it. I think
not. I would suggest the following:-
(i) All catheters are placed by experienced personell - consultant or
senior registrar
(ii) No catheter is ever left in a position where it does not easily
and repeatedly withdraw blood
(iii) All catheters are injected with radiopaque dye to ascertain tip
placement (the ostensibly 'radiopaque' catheters are not radiopaque, only
less radiolucent than the non-radiopaque catheters, and cannot be clearly
seen within the mediastinal structures[1]). We use by preference, and
virtually exclusively, the radiolucent catheter 'Epicutaneo-cave catheter'
(Vygon).
(iv) Dye injection should preferably continue while the radiograph is
taken so a blush of dye can be seen exiting the end of the catheter,
confirming it is not caught up within interstices in vessels or cardiac
chambers.
The evidence against right atrial placement seems to be based on
anecdotal experience of catheters which are mostly known to be
inappropriately placed, as your correspondent states 'accompanied by
angulation, curvature or looping of the line'. I would not like to expose
my patients to a 'small risk of thrombosis or hydrothorax' because of some
legal imperative derived from dogmatic pronouncements based on a small
number of adverse experiences. The true problem seems to be failure to
adequately assess line placement, not proper placement free in the right
atrium.
(1) Reece,A, Ubhi,T, Craig,AR, Newell,SJ : Positioning long lines:
contrast versus plain radiography - Arch Dis Child Fetal Neonatal Ed 2001;
84:F129-130
I note with deep interest the article by Dr. Chiswick on the dilemma
surrounding the issues of withdrawal of intensive care from a sick newborn
infant. I would like to highlight one aspect of 'withdrawal' which I felt
was missing in this thought provoking article.
Although the most common scenario entailing withdrawal of intensive
care is either surrounding an 'end of life decision' or 'quality...
I note with deep interest the article by Dr. Chiswick on the dilemma
surrounding the issues of withdrawal of intensive care from a sick newborn
infant. I would like to highlight one aspect of 'withdrawal' which I felt
was missing in this thought provoking article.
Although the most common scenario entailing withdrawal of intensive
care is either surrounding an 'end of life decision' or 'quality of life
decision' (as Dr. Chiswick puts in the article) ,the article does not deal
with the issue of a third, perhaps the most painful, scenario. This is of
a baby who has unfortunately suffered severe organ (usually pulmonary or
neurological) damage in the process of prior intensive care. It is often
possible that these babies come off the ventilator after a prolonged
suffering ,not only for the baby but also for the parents. They may stay
'well' for a period and then often deteriorate from a new insult, like new
infection, even when they are in the baby unit. What do we do then when we
know the futility of reintroducing intensive care? We often counsel the
parents against intensive care on the grounds of a combination of the
inevitability of dying and the even worse quality of life were our new
efforts to succeed. The result is often the 'holding back' of intensive
care.
Are we terminating life in that case ?
This I feel is the grey area between the clear cut 'end of life' and
'quality of life' situations. This is the instance when a parent will need
the most support, information and sympathy from doctors and nurses as they
have seen their baby fight, survive and then die in front of them. This is
all the more difficult for them as sometimes they do not get enough time
to think before giving the consent because the intercurrent illness comes
on quickly.
The other issue is about introducing opiates in these babies after a
decision has been made to withhold intensive care. After we have made a
decision, along with parents, to withhold intensive care the babies often
live for quite a few hours during which he or she almost inevitably goes
through a hideous sensation of slow asphyxia, undoubtedly causing life
long impressions for the parents. Many in this situation would not
hesitate to give opiate analgesics. However, few would give
'unconventional doses' if it is needed - the grounds being that it would
tantamount to
euthanasia. Do we have the right to take this moral high ground once we
have decided, albeit with someone else, not to treat a suffering human
being?
If the parents can give consent for withdrawal or withholding of life
prolonging measures, can they not give consent to curtail suffering once
we have already decided not to treat the baby?
I strongly feel that this requires open and honest debate.
Baumer reports the results of large multi-centre study comparing the
effects of patient triggered ventilation (PTV) with conventional
ventilation (IMV)1. There appears to be no benefit from PTV compared to
IMV in death rate, development of chronic lung disease, pneumothorax rates
and cerebral ultrasound abnormality. In addition, because of an increased
trend toward a higher pneumothorax rate, Baumer conc...
Baumer reports the results of large multi-centre study comparing the
effects of patient triggered ventilation (PTV) with conventional
ventilation (IMV)1. There appears to be no benefit from PTV compared to
IMV in death rate, development of chronic lung disease, pneumothorax rates
and cerebral ultrasound abnormality. In addition, because of an increased
trend toward a higher pneumothorax rate, Baumer concludes that at present,
PTV delivered with either the SLE 2000 or the Dräger babylog 8000
ventilators cannot be recommended for infants of less than 28 weeks
gestation with respiratory distress syndrome (RDS).
However, we are concerned that this may be a premature conclusion
given the significant difference in PTV delivered by the two main
ventilators used and the potential heterogeneity of clinical practice
within the different centres involved, despite agreed ventilation
protocols. Dimitriou et al2 demonstrated that neonates and infants trigger
a significantly lower proportion of breaths using the SLE 2000, an airway
pressure triggered ventilator, compared with the Dräger babylog 8000, an
airflow triggered ventilator that provides synchronised intermittent
positive pressure ventilation (SIPPV). Attempts to optimise the trigger
rate of the SLE 2000 ventilator by increasing pressure sensitivity often
results in auto triggering as discussed by Baumer. Therefore the PTV modes
of the two ventilators are substantially different. This prompts us to ask
whether the findings of this multi centre study are only applicable to PTV
provided by the SLE 2000? Would there have been a different outcome if all
the triggered babies had received SIPPV?
It is not known how many of the 40/213 babies of less than 28 weeks
gestation who had pneumothoraces were receiving SIPPV. As only 11%
(52/465) of all triggered babies ever received SIPPV, we surmise that very
few of the 40 were ventilated in this way. Is it fair to conclude that the
Dräger babylog 8000 has a trend to pneumothorax on SIPPV?
In a separate smaller study Baumer also reports 120 patients in three
centres randomly assigned to either the Dräger babylog 8000 or the SLE
2000 ventilator, and found a non-significant trend to higher pneumothorax
rate, chronic lung disease and death for the former group. But we are not
told how many of the babies were actually on trigger mode (PTV or SIPPV).
They could all have been receiving IMV on the Dräger babylog 8000.
Therefore is it possible that SIPPV is not being tested?
A further finding was a significantly higher rate (124/463) of
triggered babies that departed from their assigned mode of ventilation, 45
of these failing to trigger their ventilator. Were they all on the SLE
2000 ventilator, as Dimitriou2 would predict?
Finally, we note that 10 of the 22 neonatal units each recruited less
than 20 patients over the four year period, one contributing only 1
patient. Could the technique of PTV ventilation in units contributing so
few numbers be different to those enrolling 60-136 neonates over the same
period, despite prior visits from the trial co-ordinator? Would a logistic
regression for morbidity against number of patients contributed from each
unit reveal that the greatest morbidity occurred in units which
contributed fewer patients, rather than those using PTV or SIPPV modes?
Given the heterogeneity of the units involved and the significant
difference in ventilators used, we think that it is premature to dismiss
SIPPV on the Dräger babylog 8000 in neonates less than 28 weeks gestation
with RDS. We agree with Baumer that further studies are required, and
extend his conclusion by saying that PTV with the SLE 2000 (n=411) rather
than SIPPV from the Dräger babylog 8000 ventilator (n=52), cannot be
recommended in this group.
MARGARITA BURMESTER, ANDY PETROS
Intensive Care Units, Great Ormond Street Hospital London WC1N 3JH, UK
1. Baumer JH. International randomised controlled trial of patient
triggered ventilation in neonatal respiratory distress syndrome. Arch Dis
Child Fetal Neonatal Ed 2000;82:F5-10.
2. Dimitriou G, Greenough A, Laubscher B, Yamaguchi N. Comparison of
airway pressure triggered and airflow triggered ventilation in very
immature infants. Acta Paediatrica 1998;87:1256-60.
I am reassured by Dr Lee et al’s response indicating that the same secondary screeners worked in both hospitals in their study. I am not so convinced that their interpretation of sensitivity is correct but this does not affect their conclusions, as there is no reason to suspect that the secondary screeners acted differently at the two hospitals. With that information I accept that they have indeed prove...
I am reassured by Dr Lee et al’s response indicating that the same secondary screeners worked in both hospitals in their study. I am not so convinced that their interpretation of sensitivity is correct but this does not affect their conclusions, as there is no reason to suspect that the secondary screeners acted differently at the two hospitals. With that information I accept that they have indeed proved their point.
The letter from Dr Mantadakis addresses the important issue of the
absence of randomised studies on the clinical effectiveness of the
interventions used to prevent the possible severe sequelae of fetal
alloimmune thrombocytopenia. Studies in small series are suggestive of
some benificial effect of the current interventions like high dose
intravenous immunoglobulin to the mother or intrauterine transfusion of
HPA compat...
The letter from Dr Mantadakis addresses the important issue of the
absence of randomised studies on the clinical effectiveness of the
interventions used to prevent the possible severe sequelae of fetal
alloimmune thrombocytopenia. Studies in small series are suggestive of
some benificial effect of the current interventions like high dose
intravenous immunoglobulin to the mother or intrauterine transfusion of
HPA compatible platelets. However, many in the field share concerns that
the quality of evidence available to the clinical community is not meeting
the standards required today. We therefore support her call for a multi-
centre study as the only way forward to achieve further improvements in
the management of this severe condition which is effecting 1 in 1000
neonates.
We read the recent article by Embleton et al with interest.[1] We accept their conclusion that foot length is an accurate predictor of
nasotracheal tube length in neonates, and is at least as accurate as the
conventional weight based estimation. We however wish to point out that
palpation of the tip of the endotracheal tube (ETT) in the suprasternal
fossa continues to provide the simplest means to ens...
We read the recent article by Embleton et al with interest.[1] We accept their conclusion that foot length is an accurate predictor of
nasotracheal tube length in neonates, and is at least as accurate as the
conventional weight based estimation. We however wish to point out that
palpation of the tip of the endotracheal tube (ETT) in the suprasternal
fossa continues to provide the simplest means to ensure its correct
placement during emergency tracheal intubation when weighing the neonate
or measuring its foot length may not be practical or appropriate.[2,3] Given
that the “safety zone” for the tracheal tube tip placement in neonates is
only ~2.5 cms, the natural tendency is for the ETT to be located too
distally.[3] The placement of the ETT tip in the suprasternal fossa helps
avoid the consequences of intubation of the right main bronchus. We have
found this method useful in achieving optimal placement of the ETT for
emergency intubation as well as for elective intubation and surfactant
instillation in high-risk neonates (e.g. birth weight £1000 grams, those
with congenital diaphragmatic hernia). We have observed that if the tip of
the tube can not be felt in the suprasternal fossa,it is too far down into
the right main bronchus. If the position of the ETT is confirmed to be in
the airway, withdrawal of the tube by a centimeter achieves its optimal
placement.Confirmation of the suprasternal location of the tip of the ETT
is facilitated by minimal forward and backward gentle movement of the tube
at the nares or the lip depending on the route of intubation.Prospective
assessment of this simple technique is warranted.
PATOLE SK, JOG SM, WHITEHALL JS
References
(1) Embleton ND, Deshpande SA, Scott D, Wright C, Milligan DWA. Foot
length, an accurate predictor of nasotracheal tube length in neonates Arch
Dis Child Fetal Neonatal Ed 2001; 85: F60-F64.
(2) Finer NN. Flexible fiber-optic bronchoscopy. In: Spitzer AR, ed.
Intensive Care of the fetus and neonate. St. Louis: Mosby, 1996: 531-7.
(3) Kuhns LR, Poznaski AK. Endotracheal tube position in the infant. Jr
Pediatr 1971; 78:991-6.
We read with interest the excellent review by Dr Ng on the fetal and neonatal hypothalamic-pituitary-adrenal axis.(1) Although the issue of antenatal administration of steroids is addressed in a separate section of the paper it is practically restricted to their antenatal use for the prevention of respiratory distress syndrome and other complications of prematurity.
We read with interest the excellent review by Dr Ng on the fetal and neonatal hypothalamic-pituitary-adrenal axis.(1) Although the issue of antenatal administration of steroids is addressed in a separate section of the paper it is practically restricted to their antenatal use for the prevention of respiratory distress syndrome and other complications of prematurity.
We would agree that this is the commonest reason for giving steroids antenatally. However albeit rare there are other indications for their administration during pregnancy for purely maternal reasons. An example is the mother who has undergone renal transplantation, where steroids may be given for prolonged periods.
Some 20 years ago we reported 5 babies (2),whose mothers being recipients of of renal transplants had received 10 mg/day of prednisone throughout pregnancy. Umbilical cord plasma cortisol levels ranged from 12.8 microgram/dl to 16.3 microgram/dl. Synachthen test yielded normal adrenal response in all but one where there was no rise of cortisol level at 30 and 60 minutes. This baby received a 10 day ACTH course following which a new Synachthen test yielded a normal resonse. We mention this experience to draw attention to other situations where adminstration of steroids may be rquired during pregnancy. We think that Dr Ng should have addressed these issues too.
References
1. Ng PC. The fetal and neonatal hypothalamic-pituitary-adrenal axis. Arch Dis Child Fetal Neonatal Ed 2000;82:F250-F254
2. Dellagrammaticas HD, Parkin JM. Maternal renal Transplantation-complications in the newborn baby. Paediatriki 1980;43:364-373
Dr HD Dellagrammaticas MD, FRCPCH
Dr Nicoletta Iacovidou MD
NICU, 2nd Department of Paediatrics University of Athens Aglaia Kyriakou Children's Hospital Athens, Greece
Lees et al report that advanced nurse practitioners (ANNPs) are
significantly more effective than trainee paediatricians in detecting
abnormalities on neonatal examination. This is an important finding but
the paper raises some methodological and clinical issues.
The authors report the sensitivity of the examinations. Given the
intrinsic trade off between sensitivity and specificity, it would...
Lees et al report that advanced nurse practitioners (ANNPs) are
significantly more effective than trainee paediatricians in detecting
abnormalities on neonatal examination. This is an important finding but
the paper raises some methodological and clinical issues.
The authors report the sensitivity of the examinations. Given the
intrinsic trade off between sensitivity and specificity, it would be
helpful if both parameters were presented, together with likelihood
ratios. The table gives the likelihood ratios for "positive" and
"negative" screening examinations for each test, based on the assumption
that all children in each hospital were screened. All 95% confidence
intervals for ANNPs and trainee paediatricians overlap.
LR +ve (95% CI)
LR -ve (95% CI)
Hips: Trainee
13.1 (9.5-16.5)
0.28 (0.14-0.47)
ANNP
10.4 (8.5-11.9)
0.04 (0.01-0.21)
Eyes: Trainee
231.0 (60.2-772.0)
0.7 (0.36-0.88)
ANNP
589.5 (224.8-1440.9)
0 (0.0-0.39)
Heart: Trainee
215.0 (75.9-577.7)
0.61 (0.39-0.8)
ANNP
1117.0 (179.9-6736.0)
0.5 (0.24-0.76)
The second issue is that 53/5027(1.05%) are classified as having
abnormal hips, approximately ten times the risk of established dislocation
in an unscreened population. The clinically appropriate definition of
"abnormal hip" used here must include many children whose hips would have
"normalised" without intervention. This may signficantly bias estimates of
test performance.
The consequences associated with both missing true cases and over-
referring normal children need to be traded against one another. Childre
referred have the potential to overload the diagnostic services and may
suffer long term effects from parental anxiety generated. In addition,
over referral from screening examinations may lead to over treatment of
normal children. "Diagnostic" assessments are themselves test that are
seldom 100% specific: the greater the number of children referred for
diagnostic assessment, the greater the number who will be unnecessarliy
treated.
Presentation only of sensitivity leads the authors to suggest that
skill mix at routine neonatal examination is more effective. However,
calculation of specificity and likelihood ratios may lead to a less clear
cut conclusion.
Harding et al state that the problem of hypernatraemic dehydration in breastfed babies is attributable to: "the reluctance of midwives to weigh breastfed infants". They imply that weighing between 72 and 96 hours would be an effective intervention, but provide no evidence to support this claim.
It does not surprise me that the views of midwives and consultant neonatologists differ on this point. Whe...
Dear Editor,
We thank Dr Cliona Ni Bhrolchain for her interest in our study [1] and for the points she raises, but we disagree with her interpretation.
She is correct in noting that the referrals for eye and cardiac abnormalities were routed through senior paediatricians, but wrong to conclude that this would invalidate the results. The same individuals at each hospital performed this senior review, an...
Dear Editor,
The debate regarding placement of central venous catheter tips in neonates leaves me puzzled. We have been using percutaneously placed central venous catheters in our unit since 1978, with the aim of tip placement to be in the right atrium achieved in approximately 70% of catheters. I have prospectively maintained records of every baby, their diagnoses, managements (including central venous cathete...
Dear Editor
I note with deep interest the article by Dr. Chiswick on the dilemma surrounding the issues of withdrawal of intensive care from a sick newborn infant. I would like to highlight one aspect of 'withdrawal' which I felt was missing in this thought provoking article.
Although the most common scenario entailing withdrawal of intensive care is either surrounding an 'end of life decision' or 'quality...
Editor,
Baumer reports the results of large multi-centre study comparing the effects of patient triggered ventilation (PTV) with conventional ventilation (IMV)1. There appears to be no benefit from PTV compared to IMV in death rate, development of chronic lung disease, pneumothorax rates and cerebral ultrasound abnormality. In addition, because of an increased trend toward a higher pneumothorax rate, Baumer conc...
Dear Editor
I am reassured by Dr Lee et al’s response indicating that the same secondary screeners worked in both hospitals in their study. I am not so convinced that their interpretation of sensitivity is correct but this does not affect their conclusions, as there is no reason to suspect that the secondary screeners acted differently at the two hospitals. With that information I accept that they have indeed prove...
The letter from Dr Mantadakis addresses the important issue of the absence of randomised studies on the clinical effectiveness of the interventions used to prevent the possible severe sequelae of fetal alloimmune thrombocytopenia. Studies in small series are suggestive of some benificial effect of the current interventions like high dose intravenous immunoglobulin to the mother or intrauterine transfusion of HPA compat...
Dear Editor,
We read the recent article by Embleton et al with interest.[1] We accept their conclusion that foot length is an accurate predictor of nasotracheal tube length in neonates, and is at least as accurate as the conventional weight based estimation. We however wish to point out that palpation of the tip of the endotracheal tube (ETT) in the suprasternal fossa continues to provide the simplest means to ens...
We read with interest the excellent review by Dr Ng on the fetal and neonatal hypothalamic-pituitary-adrenal axis.(1) Although the issue of antenatal administration of steroids is addressed in a separate section of the paper it is practically restricted to their antenatal use for the prevention of respiratory distress syndrome and other complications of prematurity.
We would agree that this is the commonest...
Dear Editor
Lees et al report that advanced nurse practitioners (ANNPs) are significantly more effective than trainee paediatricians in detecting abnormalities on neonatal examination. This is an important finding but the paper raises some methodological and clinical issues.
The authors report the sensitivity of the examinations. Given the intrinsic trade off between sensitivity and specificity, it would...
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