Prematurity Flashcards
(15 cards)
Prematurity
A baby born before 37 completed weeks of gestation.
Prenatal gestational age is assessed based on what 4 parameters?
a) First day of LMP- very reliable if dates are remembered
b) Fetal Quickening- Perception of fetal movement by the mother.
* Date of 1st reported fetal activity by mother (18–20 wks for primigravida, 16–18 wks for multigravida).
c) Physical examination of the mother
* Fundal height- measure size of uterus, which corresponds to gestational age in weeks between 12 and
36 weeks for a vertex fetus.
* McDonald’s rule: use HOF to calculate the duration of pregnancy in weeks or months.
In months: fundal height measurement (in cm) × 2 /7 = duration of pregnancy in months
in weeks: fundal height measurement (in cm) × 8/7 = duration of pregnancy in weeks
d) Prenatal ultrasound
e) History of assisted reproduction: If pregnancy resulted from ART
Catergories of prematurity
There are two major categories:
a) Indicated preterm births (25% of all preterm births) include deliveries prompted by concerns regarding
maternal or fetal well-being.
b) Spontaneous preterm births (70% of all preterm deliveries) include deliveries that follow either
spontaneous labor or PPROM. Preterm labor - 40%-50% and PPROM-25%
Classification of prematurity based on gestational age
a) Extremely preterm <28 weeks
b) Very preterm 28 wks to 31 wks + 6days
c) Moderately preterm 32 wks to 33 wks + 6days
d) Late preterm 34 wks to 36 wks + 6 days
e) Preterm <37 weeks
Birthweight classification
a) Extremely low birthweight (ELBW)- less than 1000g (<1kg)
b) Very low birthweight (VLBW)- Bwt 1000g-1499g
c) Low birthweight (LBW)- Bwt 1500g- 2499g
d) Normal birthweight neonate Bwt 2500-3999g
e) Macrosomia–Bwt 4000g and above
Causes of prematurity
– as for preterm labour
Manifestations of prematurity
a) Weight is 2500 g or less
b) Usually, length is less than 44 cm
c) Head circumference disproportionately exceeds that of the chest.
d) Soft skull bones with wide sutures & posterior fontanelle
e) Soft and flat pinnae of ears.
f) Eyes are kept closed
g) Skin is;
Thin, red & shiny, due to lack of subcutaneous fat
Covered by lanugo and vernix caseosa.
h) Muscle tone is poor.
i) Plantar deep creases are not visible before 34 weeks.
j) Undescended testicles
k) Labia minora are exposed because the labia majora are
not in contact. There is a tendency of herniation.
l) Nails are not grown right up to finger tips
Diagnosis of prematurity
Dsis of prematurity is done by assessing GA at birth.
This is done by using Ballard scoring system
6 physical parameters: Skin, Lanugo hair, ear
(Pinna and Recoil), genitalia, sole creases, breast.
6 neuromuscular parameters: arm recoil, scarf
sign, popliteal angle, dorsiflexion, heel to ear and
wrist window + ventral suspension
Examination of premature baby
Completely undress the baby, ensure that the baby does not become
hypothermic.
Examine the following:
General appearance, Colour of baby, skin lesions
Observe and palpate the abdomen
Plot anthropometry (weight, length and head circumference)
Palate, genitalia, hips, hernia sites and anus (position/patency)
Spontaneous activity of infant
Red reflex in both eyes
CVS: Palpate all pulses, heart sounds and murmur
R/S: Signs of respiratory distress( nasal flaring, grunting resprations,
recessions, laboured breathing & cyanosis), patency of upper airway
Spine
Neurological: Do a Ballard score for premature (plot on standard
growth chart)
Head control by pulling to sit
Moro, grasp and suck reflex
Truncal control in ventral position
Palpate anterior fontanelle
Complications of a preterm neonate
- Asphyxia- due to anatomical and functional immaturity
- Intraventricular hemorrhage (IVH)- resulting from intense congestion of the choroid
plexus which may produced by anoxia - Hypothermia- due to reduced subcutaneous as well as brown fat, and very often fails to
maintain thermoneutral range of temp - Pulmonary syndrome- This includes:
a) Pulmonary edema
b) Intra-alveolar hemorrhage results from the effects of hypoxia
c) Respiratory distress syndrome (RDS)- major causes of death in preterm babies born before 34 weeks due to
deficient lung surfactant leading to pulmonary atelectasis leading to hypoxia & acidosis
d) Bronchopulmonary dysplasia
e) Persistant Pulmonary HTN - Cerebral hemorrhage- due to sev degree of moulding leading to subdural or subarachnoid hemorrhage,
hypoprothrombinemia and hypoxia of fragile subependymal capillaries leading to IVH - Fetal shock
- Heart failure-
- Oliguria, anuria - due to immature kidneys
- Infection- less protective Igs transferred from mother to a preterm baby and so both the humoral and cellular
immune response is poor. Common infections are; bronchopneumonia, meningitis and necrotizing enterocolitis. - Jaundice- hepatic insufficiency lead to inadequate conjugation and a rise in unconjugated bilirubin produced by
the excessive hemolysis - Anemia- due to lack of stored Fe, bone marrow hypofunction and excessive haemolysis
- Retinopathy of prematurity- caused by abnormal neovascularization, related to liberal administration of high
conc of O2 above 40% for a prolonged period (1–2 days) following birth and blindness is due to the formation of
an opaque membrane behind the lens. - Persistent PDA is inversely proportional to gestational age. An ECHO is recommended
Late Preterm Infants causes of morbidity
Late preterm infants (34-37) wks are 6 X more likely to die in the 1st wk of life and 3X more likely to die in the 1st yr
Respiratory distress
Hypothermia
Sepsis
Hypoglycemia
Inadequate feeding/dehydration
Hyperbilirubinemia
Growth and developmental issues
Immature brain
Principles of care for babies requiring special care
- To maintain normothermic- keep delivery room warm, dry and then wrap baby with a warm towel, keep the baby
with mother—skin to skin contact - Adequate humidification to counter balance increased insensible water loss
- Oxygen therapy and adequate ventilation
- To prevent infection
- To maintain nutrition and adequate nursing care
Care of a preterm neonate
immediate management following birth
Clamp cord quickly to prevent hypervolemia and development of hyperbilirubinemia.
Keep cord length long (about 10–12 cm) in case, exchange transfusion is required.
Promptly and gently clear air passage of mucus using a mucus sucker.
Adequate oxygenation through mask or nasal catheter in concentration not exceeding 35%.
Wrap baby including head in a sterile warm towel (keep normothermic 36.5–37.5°C).
Hypothermia and its sequelae: Hypoxia → Hypoglycemia → anaerobic metabolism → metabolic acidosis.
Give vitamin K 1 mg IM to prevent hemorrhagic manifestations.
Family counseling before delivery on: survival rate, short- and long-term complications and treatment options
Administer antenatal steroids for lung maturation and magnesium for neuroprotection
Resuscitation- ABC
Normothermia- premature babies are extremely thermolabile- easily develop hyperpyrexia or hypothermia.
Place smaller babies naked in incubator where temperature at (36–37°C) and humidity of at least 50%.
Or managed under radiant warmer with protective plastic covers.
If not possible maintain room temperature and humidity, and keep baby’s cot warm
Respiratory support: clear the airway and administer O2 via nasal prongs, face mask, CPAP, and endotracheal
intubation and mechanical ventilation
Monitor blood gases at regular intervals
Continuous O2 monitoring with pulse oximeter.
Surfactant replacement therapy is indicated in HMD
Infection: give prophylactic antibiotic therapy to babies are born following PROM.
Prevent or minimize infection
Nutrition and fluids: Human milk is the best for all low birth weight babies.
Colostrum, foremilk, hindmilk and preterm milk enable faster growth of the baby.
Premature babies should fed with the cup or OGT
Total fluid intake (TFI)- first day use 10% dextrose, the next day use ½ RL in 10% dextrose
outline the total fluid intake regimen for preterm babies
starting points:
* <1000g - start at TFI 90ml/kg/day when less than 24 hours of life, Keep NPO.
If and when mother is available, after 24 hours, start EBM at 12ml/kg/day.
If mother is not available or EBM isn’t available please keep NPO up to >24hours of life.
Also start amino acid on day 2.
For ELBW if amono acids are available
Day 1, 12mls/kg/day
Day 2, 24mls/kg/day
Day 3, 36mls/kg/day
* Bwt 1000-1199g starting TFI 80ml/kg/day. Keep NPO on day one but if mother is, available and
expressing, start EBM also at 24 ml/kg/d (to be included to TFI)
* Bwt 1200-1499g starting TFI 70ml/kg/D. If distress is not severe, start EBM 24ml/kg/day
* Bwt 1500 and above- starting TFI 60ml/kg/day. If distress is severe for babies less than 2kg, you can
keep NPO till stable enough. Otherwise these are babies you can start half n half feeds and IVF if they
are stable enough
* HIE babies starting TFI for <24hours old is 40ml/kg/day. Keep NPO
Early feeds can predispose to NEC due to poor perfusion insult of gut contents
* Additional supplements: add MVT after 48hrs, orofer after 28th day
Prognosis of preterm
Survival is directly related to the birth weight.
A baby weighing > 1500 g is most likely to survive by 95%
But meticulous care at birth is more important than birth weight.
With intensive neonatal care, survival rate of a baby weighing 751–1000g is to the extent of 80%.
With gestational age < 23 weeks, mortality is > 97%.
Deaths are due to RDS and other complications and increased incidence of congenital malformations.
Long-term prognosis: Major handicaps (cerebral palsy), hearing loss, behavior disorder, chronic lung disease
and poor growth are observed
