Ebook A manual of neonatal intensive care (5/E): Part 1

The fifth edition includes evidence-based advice wherever possible, and
the material has been expanded to include sections on antenatal diagnosis,
intrapartum monitoring, risk management, common postnatal ward problems and skin disorders. Advice on counselling and prognosis is included
throughout.
Key features:
★ Provision of concise, up-to-date information in an accessible style
★ “Key points” sections to aid rapid assimilation of information
★ Reference to evidence-based medicine or the physiological basis behind
management decisions to enable readers to evaluate the advice given
★ Complete redesign of the layout and update of the material with many
new sections

Janet M Rennie is Consultant and Senior Lecturer in Neonatal Medicine,
Elizabeth Garrett Anderson Obstetric Wing, University College London
Hospitals, London, UK.
Giles Kendall is Consultant in Neonatal Medicine, Elizabeth Garrett
Anderson Wing, University College London Hospitals, and Honorary
Senior Lecturer in Neonatal Neuroimaging and Neuroprotection, Institute
for Women’s Health, University College London, London, UK.

5th edition

A Manual of Neonatal Intensive Care provides invaluable guidance
for trainees in paediatrics, neonatology and neonatal nursing and forms a
useful ready-reference for the practising paediatrician and nurse.

A Manual of Neonatal Intensive Care

The fifth edition of this highly successful and well-regarded book has been
completely revised and restructured, but continues to provide the busy paediatrician or nurse working in neonatal intensive care units with sound and
practical advice on the diagnosis and management of common neonatal

problems. A Manual of Neonatal Intensive Care is unique in style,
providing guidance in a clear, readable and accessible format.

A Manual of Neonatal
Intensive Care
fifth edition

Rennie
Kendall

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A Manual of Neonatal
Intensive Care

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A Manual of Neonatal
Intensive Care
Fifth edition
Janet M Rennie MA MD FRCP FRCPCH FRCOG DCH
Consultant and Senior Lecturer in Neonatal Medicine, Elizabeth Garrett Anderson
Obstetric Wing, University College London Hospitals, London, UK
Giles S Kendall BSc(Hons) MB BS MRCPCH PhD
Consultant in Neonatal Medicine, Elizabeth Garrett Anderson Wing, University
College London Hospitals, London, UK
Honorary Senior Lecturer in Neonatal Neuroimaging and Neuroprotection, Institute
for Women’s Health, University College London, London, UK

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CRC Press
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Contents
Abbreviationsxiii
Prefacexvii
Acknowledgementsxvii

Part 1Organization and delivery of care
1 Epidemiology and neonatal outcomes
2
Epidemiology: definitions in perinatal medicine
2
Neonatal outcomes
4
References
7
Further reading
7

Web links
7
2 Organization of neonatal care
8
Definition of levels of care
8
Provision of intensive care facilities
10
References11
3 Clinical governance, risk management and legal aspects
of neonatal practice
12
Clinical governance
13
Serious untoward incident reporting and investigation
13
Medical negligence
13
Consent14
Death15
Further reading
17

Part 2 Pregnancy and early neonatal life
4 Maternal–fetal medicine for the neonatologist
20
Prenatal diagnosis of fetal disease
20
Maternal conditions affecting the fetus
23

Hypertension in pregnancy
26
Multiple pregnancy
26
Immunological conditions
27
Placental insufficiency
27
Preterm membrane rupture
27
Prelabour rupture of the membranes at term
27
Induction of labour
28
Intrapartum monitoring
28
Mode of delivery
30
References31
Further reading
31
Further information
31
5 Genetic disease
32
Good ‘handles’ for genetic diagnosis
33
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6

7

8

9

Further reading
34
Web links
34
Neonatal resuscitation and stabilization
35
Physiological adaptation at birth
35
Neonatal resuscitation
36
Resuscitation equipment
36
Practice of neonatal resuscitation
40
Special situations in neonatal resuscitation
45
Problems with resuscitation
45

First-hour care after resuscitation
47
References50
Further reading
50
Nursing, monitoring and transport of the sick neonate
51
Thermal control
51
Minimal handling
53
Monitoring55
Clinical and laboratory monitoring
60
Neonatal transport
62
References63
Physical examination of the newborn
64
Timing of the examination
65
The examination
65
Reference66
Further reading
66
Web link
67
Congenital anomalies and common postnatal problems
68

Common findings in day-to-day practice
69
Reference76
Further reading
76
Web links
77

Contents

Part 3Nutrition and fluid balance
10 Fluid and electrolyte balance
80
Neonatal renal function and physiology
80
Water81
Sodium86
Potassium88
Hydrogen ions and bicarbonate
88
Calcium and phosphate
89
Magnesium90
Practical fluid and electrolyte management
90
References91
Further reading
92
11 Neonatal enteral nutrition
93

Infant nutrient requirements
93
Which milk to give?
97
Anti-infection agents
98
Healthy low birth weight babies
101
Sick low birth weight babies
103

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Contents

References104
Further reading
105
Web link
105
12 Parenteral nutrition
106
Composition of parenteral nutrition solutions
106
Intravenous feeding solutions

110
Route of infusion
110
Monitoring of intravenous feeding
110
Complications of parenteral nutrition
111
Acknowledgement112
References112
Further reading
112

Part 4Diseases and their management
13 Acute disorders of the respiratory tract
114
Respiratory physiology
114
Differential diagnosis of neonatal respiratory disease
123
Respiratory distress syndrome; hyaline
membrane disease
127
Treatment of respiratory distress syndrome
133
Continuous positive airways pressure
139
Mechanical ventilation: intermittent positive
pressure ventilation
140
Ventilation142

Sudden deterioration on intermittent positive
pressure ventilation
150
Gradual deterioration on intermittent positive
pressure ventilation
151
Transient tachypnoea of the newborn
154
Meconium aspiration
155
Pulmonary interstitial emphysema, pneumothorax,
pneumomediastinum157
Massive pulmonary haemorrhage
161
Persistent pulmonary hypertension of the newborn
162
Pulmonary hypoplasia
165
Congenital malformations affecting the respiratory tract
166
References167
Further reading
168
14 Chronic lung disease
170
Aetiology170
Natural history
172
Clinical features
172

Investigations172
Differential diagnosis
173
Histology173
Radiology173
Interventions for chronic lung disease
173
Wilson–Mikity syndrome
178
References179
Further reading
179
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Contents

Web link
179
15 Apnoeic attacks
180
Definition of apnoea and periodic breathing
180
Clinically significant apnoea
180
Recurrent apnoea of prematurity

181
Pathophysiology181
Radiology183
Treatment183
References184
Further reading
184
16Infection
185
Infection control in neonatal units
185
Host defences in the newborn and
the inflammatory response
186
Bacterial infection in the newborn
188
Maintenance of homeostasis
196
Virus infections
206
Congenital infections
210
Effect of perinatal maternal infections
212
References215
Further reading
216
17 Neurological problems
217
Assessment of the nervous system

217
Convulsions in the newborn
217
Hypoxic ischaemic encephalopathy
220
Focal vascular lesions
224
Extracranial haemorrhage
224
Intracranial haemorrhage
225
Preterm white matter injury/periventricular
leukomalacia230
Neonatal hypotonia
232
Nerve palsies
232
Central nervous system malformations
233
References235
Further reading
235
18 Metabolic disorders, including glucose homeostasis
and inborn errors of metabolism
236
Glucose metabolism in the newborn
236
Clinical causes of hypoglycaemia
239
Unusual causes of neonatal hypoglycaemia

243
Neonatal hyperglycaemia
244
Inborn errors of metabolism
244
Causes of severe early metabolic disease
247
References252
Further reading
252
19 Endocrine disorders
253
The neonate with ambiguous genitalia
253
Congenital adrenal hyperplasia
255
Thyroid problems
257
Further reading
258

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Contents

20 Neonatal jaundice and liver disease
259
Physiology260
Bilirubin biochemistry
260
Bilirubin encephalopathy (kernicterus)
261
Differential diagnosis of neonatal jaundice
263
Causes of unconjugated hyperbilirubinaemia
263
Breast feeding and jaundice
264
Some specific causes of unconjugated
hyperbilirubinaemia265
Prolonged neonatal jaundice
266
Prolonged unconjugated hyperbilirubinaemia
266
Conjugated hyperbilirubinaemia
266
Treatment of neonatal jaundice
269
References272
Further reading
272
21 Gastroenterological problems
273
Basic physiology of the fetal and neonatal gut
273

Cleft lip and palate
275
Oesophageal atresia and tracheo-oesophageal fistula
275
Congenital diaphragmatic hernia
276
Intestinal obstruction
277
Exomphalos278
Gastroschisis278
Necrotizing enterocolitis
278
Isolated bowel perforation
283
Short bowel syndrome
283
Gastro-oesophageal reflux
284
The baby with persistent vomiting
284
Persisting diarrhoea
285
Haematemesis, melaena and bloody stools
in the newborn
285
Hirschsprung’s disease
286
References286
Further reading
286

22 Congenital heart disease in the neonatal period
287
The fetal circulation
287
Changes in the circulation at birth
288
Presentation of heart disease
289
Investigations290
Heart murmurs in asymptomatic babies
291
Congenital heart disease presenting as
shock with acidosis
294
Congenital heart disease presenting as
heart failure
295
Treatment of heart failure in the newborn
296
Individual conditions which can cause
heart failure or shock
296
Cyanotic heart disease
300
Arrhythmias in the neonatal period
305
References306
Further reading
306

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23 Neonatal haematology
307
Anaemia in the neonate
307
Haemolytic disease of the newborn
311
Guidelines for direct antiglobulin test-positive babies
315
Bleeding and bruising
316
Neonatal thrombosis
321
References322
Further reading
322
Web links
322
24 Genitourinary problems
323
Urine323
Renal failure
324
Urinary tract infection

326
Congenital nephrotic syndrome
326
Renal malformations
326
Genitourinary tract anomalies
330
References331
Further reading
331
25 Eye disorders
332
Retinopathy of prematurity
332
Buphthalmos (neonatal glaucoma)
335
Cataract336
Conjunctivitis336
Strabismus336
References336
Further reading
336
26 Skin disorders
337
Common benign neonatal skin disorders
338
Other miscellaneous neonatal skin conditions
339
Birthmarks and vascular disorders
340

Further reading
341
27 Orthopaedic and bone disorders
342
Fractures342
Dislocations343
Skeletal malformations
343
Further reading
346
Web link
346
28 Neonatal abstinence syndrome
347
Maternal opiate abuse
347
References350
Further reading
350

Contents

Part 5 Procedures and their complications
29 Procedures and iatrogenic complications
Neonatal procedures
Blood sampling and cannulation
Umbilical catheterization
Intraosseous lines
Endotracheal intubation

352
352
352
356
358
358

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Contents

Urine collection
362
Cerebrospinal fluid collection
363
Reference364
Further reading
364

Part 6 Useful information
Appendix 1 Growth charts
366
Appendix 2 Assessing the ill neonate
369
Respiratory severity scoring

369
Clinical Risk Index for Babies – CRIB II score
371
Further reading
371
Appendix 3 Normal blood pressure
372
Term neonates
372
Preterm infants
372
References374
Appendix 4 The neonatal electrocardiogram
375
Rate and rhythm
375
The axis
375
Information about the atria
376
Information about the ventricles
376
Appendix 5 Normal biochemical values in the newborn
379
Appendix 6 Haematological values in the newborn
382
References383
Appendix 7 Normal cerebrospinal fluid values
in the newborn
384

Traumatic lumbar puncture
384
Reference384
Index
385

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Abbreviations
ACTH
adrenocorticotrophic hormone
ACV
assist control ventilation
ADH
antidiuretic hormone
AED
antiepileptic drug
AFPalpha-fetoprotein
ANP
atrial natriuretic peptide

APTT
activated partial thromboplastin time
ARF
acute renal failure
ASD
atrial septal defect
BAPM
British Association of Perinatal Medicine
BP
blood pressure
BPD
bronchopulmonary dysplasia
CAH
congenital adrenal hyperplasia
CCAM
congenital cystic adenomatoid malformation
CDH
congenital diaphragmatic hernia
CHD
congenital heart disease
CLD
chronic lung disease
CMVcytomegalovirus
CNS
central nervous system
CNST
Clinical Negligence Scheme for Trusts
CONS
coagulase-negative staphylococci
CP

cerebral palsy
CPAP
continuous positive airways pressure
CRP
C-reactive protein
CSF
cerebrospinal fluid
CSVT
cerebral sinovenous thrombosis
CTG
cardiotocogram (cardiotocography)
CVC
central venous catheter
CVP
central venous pressure
CVS
chorionic villus sampling
CXR
chest X-ray
DAT
direct antiglobulin
DDH
developmental dysplasia of the hip
DEHSI
diffuse excessive high signal intensity
DIC
disseminated intravascular coagulation
DMSA
dimercaptosuccinic acid
DPGdiphosphatidylglycerol

DPL
dipalmitoyl lecithin
DZdizygotic
EBM
expressed breast milk
ECF
extracellular fluid
ECGelectrocardiogram
ECMO
extracorporeal membrane oxygenation
EDD
expected date of delivery
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Abbreviations

EDF
end-diastolic flow
EEGelectroencephalogram
ELBW
extremely low birth weight
EPOerythropoietin
ETT
endotracheal tube
FBC

full blood count
FDP
fibrin degradation product
FFP
fresh frozen plasma
FHR
fetal heart rate
FISH
fluorescent in-situ hybridization
FRC
functional residual capacity
GBS
group B beta haemolytic streptococcus
GFR
glomerular filtration rate
GMH-IVH germinal matrix–intraventricular haemorrhage
hCG
human chorionic gonadotrophin
HCV
hepatitis C virus
HDN
haemolytic disease of the newborn
HELLP
hypertension, elevated liver enzymes and low platelets
HFNC
high-flow nasal cannula
HFOV
high frequency oscillatory ventilation
HIE
hypoxic ischaemic encephalopathy

HIV
human immunodeficiency virus
HPA
human platelet antigen
HMD
hyaline membrane disease
HTLV
human T-cell lymphotropic virus
HVS
high vaginal swab
IAP
intrapartum antibiotic prophylaxis
ICH
intracranial haemorrhage
ICP
intracranial pressure
IEM
inborn error of metabolism
IMV
intermittent mandatory ventilation
IPL
intraparenchymal lesion
IPPV
intermittent positive pressure ventilation
IUGR
intra-uterine growth restriction
IVintravenous
IVC
inferior vena cava
IVH

intraventricular haemorrhage
IVIG
intravenous immunoglobulin
LBW
low birth weight
LP
lumbar puncture
MAP
mean airway pressure
MAPCA
major aortopulmonary collateral arteries
MAS
meconium aspiration syndrome
MCAD
medium chain acyl-CoA dehydrogenase
MCT
medium chain triglyceride
MCUG
micturating cysto-urogram
MRI
magnetic resonance imaging
MRSAmeticillin-resistant Staphylococcus aureus
MZmonozygotic
NCEPOD
National Confidential Enquiry into Patient Outcome and Death
NCPAP
nasal continuous positive airway pressure

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Abbreviations

NEC
necrotizing enterocolitis
NGnasogastric
NHSLA
NHS Litigation Authority
NICE
National Institute for Health and Clinical Excellence
NICU
neonatal intensive care unit
NIPE
Newborn and Infant Physical Examination
NNAP
National Neonatal Audit Programme
NNU
neonatal unit
NO
nitric oxide
NPSA
National Patient Safety Agency
NSC
national screening committee
NT
nuchal translucency

PAPP-A
pregnancy-associated plasma protein A
PCR
polymerase chain reaction
PCV
packed cell volume
PDA
patent ductus arteriosus
PEEP
positive end expiratory pressure
PHVD
post-haemorrhagic ventricular dilatation
PIE
pulmonary interstitial emphysema
PIH
pregnancy-induced hypertension
PIP
peak inspiratory pressure
PKUphenylketonuria
PN
parenteral nutrition
PPHN
persistent pulmonary hypertension of the newborn
PPROM
preterm premature rupture of the membranes
PSV
pressure support ventilation
PT
prothrombin time
PTV

patient trigger ventilation
PUJ
pelvi-ureteric junction
PUV
posterior urethral valve
PVH
periventricular haemorrhage
PVL
periventricular leukomalacia
RBC
red blood cell
RCOG
Royol College of Obstetricians and Gynaecologists
RCPCH
Royal College of Paediatrics and Child Health
RDS
respiratory distress syndrome
ROP
retinopathy of prematurity
RSV
respiratory syncytial virus
RV
right ventricle
RVT
renal vein thrombosis
SGA
small for gestational age
SIMV
synchronized intermittent mandatory ventilation
SIPPV

synchronized intermittent positive pressure ventilation
SNRI
serotonin–norepinephrine reuptake inhibitors
SSRI
selective serotonin reuptake inhibitors
SVC
superior vena cava
SVT
supraventricular tachycardia
expiratory time
Te
TGV
thoracic gas volume
inspiratory time
Ti
TPN
total parenteral nutrition

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thyrotrophin receptor stimulating antibody
thyrotrophin releasing hormone
thyroid–stimulating hormone
tuberculin skin test
transient tachypnoea of the newborn

twin–twin transfusion syndrome
umbilical artery catheter
ultrasound scan
urinary tract infection
umbilical venous catheter
vascular endothelial growth factor
volume guarantee
vitamin K deficiency bleeding
very low birth weight
ventricular septal defect
volume targeted ventilation
vesico-ureteric junction
white blood cell (count)
Wolff–Parkinson–White syndrome

Abbreviations

TRAb
TRH
TSH
TST
TTN
TTTS
UAC
USS
UTI
UVC
VEGF
VG
VKDB

VLBW
VSD
VTV
VUJ
WBC
WPW

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Preface
Preface to the 5th edition
Unbelievably, it is now over 30 years since the publication of the first edition of A
Manual of Neonatal Intensive Care (1981). In that time, generations of residents
and neonatal nurses have come to rely on the book as a source of sound practical
advice with an explanation of the reasons behind the recommended course of action.
As before, we have aimed to distill the wisdom acquired from long experience into
a readable text supplemented with lists and tables. In a rapidly advancing field such
as this, some management strategies are controversial and lack an evidence base, and
in this situation we have suggested the course of action which we have found most
helpful while briefly outlining the alternatives. We hope that all who read and use the
book will find it helpful, and that it will stimulate their enthusiasm for neonatology,
a specialty which is challenging, varied and exciting. No working day on a neonatal
unit is ever the same; but an understanding of normal neonatal physiology and the
common response of the newborn to illness can help everyone who works in this
pressurized environment to respond and plan treatment appropriately. That has been

our aim in writing the book. We have referred to the baby as he and the mother as she
for simplicity, and hope that this does not offend the reader.

Acknowledgements
There were times during the period between the publication of the fourth edition and
delivery of the material for this fifth edition when the team at Hodder Arnold, and
more recently CRC Press, must have despaired of ever seeing the book published.
Thanks are due to Gavin Jamieson for his unending patience and encouragement and
to Francesca Naish for finally setting us deadlines which we managed to meet. Our
colleagues at UCLH have remained as supportive as ever. We would like to thank
Fiona Maguire and Elizabeth Erasmus for input into the chapters on parenteral and
enteral nutrition, respectively. We gratefully acknowledge the work of Cliff Robertson,
sole author of the first three editions. Particular thanks are due to our spouses, Ian
Watts and Kin Yee Shiu, and to the younger generation of Kendalls, Han Se and Lin
Mei, who have seen their father less than ever over the last year or so.
Janet Rennie, Giles Kendall
London
June 2012
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Part 1

Organization and
delivery of care
1 Epidemiology and neonatal outcomes

2

2 Organization of neonatal care

8

3 Clinical governance, risk management and
legal aspects of neonatal practice

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1

Epidemiology and neonatal
outcomes
Key points
■■
■■
■■

Around 7% of all births are of low birth weight (<2500 g) or preterm (<37
completed weeks of pregnancy).
About 15 per 1000 pregnancies are twin pregnancies, but 25% of all babies with
very low birth weight (<1500 g) are twins or higher multiples.
The outcome for babies born at 25 weeks of gestation or less has improved, but
there is still a high risk of death, with motor and/or learning difficulty in a high
percentage of the survivors.

■■ Epidemiology: definitions in perinatal medicine
Neonatologists need knowledge and understanding of current international, national
and local statistics in order to provide adequate information during the counselling of
parents when there is the expectation of a preterm or complicated birth. To make sense
of the published statistics it is first essential to define the terms that are commonly
used in perinatal medicine (Fig. 1.1).
Preterm: any baby born below 37 weeks’ completed gestation, i.e. less than
259 completed days of gestation, measured from the first day of the last normal
menstrual period. Extreme preterm is often used to describe delivery below 26
weeks’ completed gestation.
■■ Low birth weight: a baby with a birth weight of less than 2500 g (up to and
including 2499 g).
■■ Very low birth weight: birth weight of less than 1500 g.
■■ Extremely low birth weight (ELBW): birth weight of less than 1000 g.
■■ Stillbirth: a stillborn baby is defined as a baby born after the 24th week of
pregnancy who did not show any signs of life at any time after being born. If there
are no signs of life at birth, a baby born before 24 weeks’ gestation is classed as a
miscarriage. The stillbirth rate (see below) is the number of stillbirths expressed per
1000 live births and stillbirths.
■■ Live birth: a birth at any gestation (including below 24 weeks) where the baby
shows signs of life after delivery.

■■ Neonatal death: the death of a neonate born with signs of life (see above) within
the first 28 days after delivery. It is often subdivided into early neonatal death
within the first 7 days of life and late neonatal death occurring after the 7th day
but before the completed 28th day of life.
■■

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}

Late fetal death
(stillbirth)
Perinatal
Early neonatal
Late neonatal
Neonatal
Post neonatal
Infant

day

week

28
days

}

Rate
expressed as
deaths per
1000 total
births

deaths per
1000 live
births

year

Fig. 1.1 Definition of stillbirth and infant mortality rates

Epidemiology: definitions in perinatal medicine

Birth

Infant mortality rate: the number of infants dying within the first year of life per
1000 live births.
■■ Perinatal mortality rate: the number of stillbirths and neonatal deaths in the first
week of life per 1000 total births (live and stillborn).
■■

The Millennium Development Goal is to achieve a two-thirds reduction in mortality in
children younger than 5 years by 2015; there was a worldwide reduction of 3.1 million
neonatal deaths between 1990 and 2010. Most of the deaths still occur in sub-Saharan

Africa or south Asia, with less than 1% of the deaths in high-income countries.
The value of understanding the outcomes of babies born prematurely extends beyond
the counselling of parents and families. Such studies allow the guidance of health and
social care provision, both in the perinatal period and extending into childhood.
Around 7% of all births in the UK are of babies with birth weight <2500 g, and
about 1.2% of all births are of babies <1500 g. The percentage of ELBW babies
has risen considerably from 0.27% in 1983 to around 0.5% in 2009. Unfortunately
national data in England and Wales did not record gestational age until 2005, when
the linkage with the NHS numbers for babies was established. Data are available for
Scotland from the early 1970s and show a steadily rising trend with an increase in the
number of multiple preterm births.
The availability of gestational age-specific mortality data for England and Wales
shows that there is, as expected, a steadily declining mortality as gestational age
increases, with the exception of post-dates babies of 42 weeks (Fig. 1.2). Note the
logarithmic scale on the y-axis.
Within the UK, the mortality figures vary considerably by the ethnic origin of the
mother, and international comparisons of perinatal mortality data are often performed.
The World Health Organization has recommended that babies of gestational age below
22 weeks and birth weight below 500 g should be excluded from comparisons between
countries because of differences in incidence and reporting of births of such babies.
Valuable information about the outcome of extremely preterm babies born in
England and Wales is available from the two EPICure studies. These were prospective,
geographical studies which included all deliveries below 26 weeks, for 1995 and 2006.
The survival figures for babies admitted to the neonatal intensive care unit (NICU)
born below 26 weeks are shown in Fig. 1.3; improvement in survival is seen between
the 1995 and 2006 cohort, which is significant at 24 and 25 weeks’ gestation.
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Deaths per 1000 live births,
logarithmic scale

1000
Early neonatal
Neonatal
Infant

100

10

1

0

22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42
and
Gestational age (completed weeks)
over
Source:
ONS
childhood
mortality
statistics,
unpublished
data

Fig. 1.2 Infant mortality by gestational age, babies born in 2008, England and Wales.
Source: ONS childhood mortality statistics, unpublished data. Data from Office of National
Statistics, compiled by Allison Mc Farlane; from Rennie and Robertson (2012) with permission

100

EPICure 1 (1995)

90

EPICure 2 (2006)

Per cent survival

80
*p = 0.0006

70
60

*p = 0.002

50
40
30
20

*ns
n = 2/4

*ns
n = 26/45

10

Epidemiology and neonatal outcomes

0
22 weeks

23 weeks

24 weeks

Gestational age at birth

25 weeks

Fig. 1.3 Outcome of babies born
below 26 weeks’ gestation

There are, however, limitations in the applicability of national geographical outcomes
due to small numbers of the most extreme preterm infants and changing patterns of
neonatal care with time (use of surfactant, antenatal steroids, temperature control,
increased use of non-invasive ventilation, centralization of care, minimal handling, etc.).

■■ Neonatal outcomes
In surviving infants born extremely preterm, a number of significant medical
morbidities are seen which appear largely unchanged across the 10 years between
EPICure 1 and 2 (Fig. 1.4). Although cerebral palsy (CP) has long been monitored as

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80

Neonatal outcomes

1995

Per cent discharges

2006
60
p = 0.008

p = 0.045
40

20

0
Scan abn

Treated ROP

O2 at 36w

Home O2

Fig. 1.4 Major neonatal morbidities at discharge in infants born
<26 weeks. abn, abnormal; ROP, retinopathy of prematurity; w, weeks

an adverse outcome of preterm birth, and there is no doubt that there is an increased
risk of CP in extremely preterm babies, far more survivors of preterm birth are disabled
by their learning problems.
Severe motor outcomes such as CP are relatively rare, affecting approximately
10% of very low birth weight babies. In EPICure 1, in infants born at less than 26
weeks, 14% of surviving babies showed moderate motor disability and 4% severe
motor disability. Cognitive outcomes appear to be a continuum of disability, with a
very significant fall away in cognitive outcomes in babies born at less than 32 weeks
of gestation (Fig. 1.5). However, when assessed by the requirement for special
educational needs provision in school, the effects of even mild degrees of prematurity
can be detected (Fig. 1.6).
120

Kaufman-ABC MPC

110

n=
24 73 144

27 23 39 67

92 103 162 252 397 414 348 415 465 917 289 100

100
90
80
70

Mean + SEM
Bavarian Study 4.8 years

60
50

EPICure Study 6 years
adjusted for comparison GCA

22

24

26

30
32
34
36
28
Gestational age (weeks)

38

40

42

Fig. 1.5 Cognitive outcomes following preterm birth. ABC MPC, Assessment Battery for Children
Mental Processing Composite; GCA, general conceptual ability; SEM, standard error of the
mean. With permission from Marlow et al. (2005)

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Proportion with SEN (log scale)

0.8
0.6
0.4

0.2

0.5

0.05
24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43
Estimated gestational age (weeks)

Epidemiology and neonatal outcomes

Fig. 1.6 Percentage of children with special educational needs (SEN) by gestation at delivery
(note the logarithmic scale). Redrawn from Mackay et al. (2010). From Rennie and Robertson
(2012) with permission

It should also be recognized that the assessment of neurodisability following extreme
preterm birth varies dependent on the age of assessment. Although severe disability is
readily detectable early, some of the milder forms of disability are not detectable until
later childhood. In addition to adverse motor and cognitive outcomes, more detailed
follow-up has demonstrated significantly increased behavioural symptoms (especially
social, thought and attention difficulties), emotional disorders such as anxiety and
depression, and autistic-like disorders. Our understanding of how prematurity affects
individuals into adult life is currently very limited.
When discussing outcomes with families it is important to recognize that it takes
knowledge and experience to pitch the information at the right level, to include enough
detail to explain but not confuse; overall we aim to be ‘honest but not cruel’. Trainee
paediatricians are often asked about a baby’s prognosis, partly because they are present
on the neonatal unit at all hours of the day and night and partly because parents like
to canvass a second opinion. It cannot be stressed too often that much damage can
be done by inaccurate and ill-timed advice. As in any other area of neonatology, if in
doubt, ask! Encourage your consultants to document what they have already told the
parents and to let you sit in on the counselling sessions. Always remember that there is a
huge spectrum of disability, that there are always exceptions, and that quality of life is a
value judgement. Conflicting advice gives rise to anger and bitter resentment in parents.
In discussing the outcome after preterm birth, survival rates depend where you
start, e.g. survival of all/live born/admitted to NICU. As a rule of thumb, in surviving
infants the rates of serious impairments are currently:
23 weeks – 60% (mean IQ 72)
24 weeks – 60% (mean IQ 76)
■■ 25 weeks – 40% (mean IQ 80).

■■
■■

However, recognize that outcomes are:
1.individual and therefore quoting a mass of statistics is of limited value
2.different for boys and girls
3.related to birth weight, and birth weight for gestation as well as gestation alone.

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