Group sessions - Neonatal lecture Flashcards
Define neonatal period and infancy
Define gestational age, normal gestation time, preterm time
Neonatal period: first 28 days of life
Infancy: first 1 year of life
Gestational age is the time elapsed between the first
day of the LMP and the day of delivery
Normal gestation: 37+0 to 41+6
Preterm: born before 37+0; post-term: born after
41+6.
Define birth weight categories
Define SGA/LGA/Appropriate-for-date
Birth weight categories
≤1000gm = Extremely Low Birth Weight (ELBW)
≤1500gm = Very Low Birth Weight (VLBW)
≤ 2500gm = Low Birth Weight (LBW)
Small-for-date (SGA): BW <10th percentile
Large-for-date (LGA): BW >90th percentile
Appropriate-for-date: BW 10-90th percentile
Define normal newborn growth parameters at 37 and 40 weeks (length and weight)
Define normal head circumference at 40 weeks
Compare fetal vs post-natal circulation
Babies subjected to hypoxia > pulmonary vessel constricted > prolonged asphyxiation > Persistent pulmonary hypertension of the newborn (PPHN)
PPHN happens when your baby’s pulmonary arteries don’t open up enough, so your baby’s brain and organs don’t get enough oxygen.
Consequence of perinatal asphyxiation
Primary apnea: heart rate and BP increase, regular increased breathing/ ventilation
Secondary apnea: HR and BP drops, breathing pattern become erratic
(clinically differentiate the two stages is by tactile stimulation: crying means primary apnea, and no crying means secondary apnea and requires immediate PPV)
Causes of neonatal asphyxiation
In-utero hypoxia
¡ Placental abruptio, placenta praevia, twin-twin transfusion syndrome
Intrapartum hypoxia
¡ Uterine hyperstimulation
¡ Shoulder dystocia
Postnatal hypoxia
¡ Poor respiratory drive e.g. preterm infant, drug-induced
depression
¡ Poor cardiopulmonary function e.g. RDS, meconium
aspiration
Resuscitation methods for neonatal asphyxia
Helps to establish transition from fetal to post-natal circulation as quickly as possible
¡ Keep warm
¡ Airway opening – suction, position neck
¡ Tactile stimulation
¡ Positive pressure ventilation
¡ External chest compression
¡ Drug administration
Cord clamping
- Benefits of delayed clamping
- Drawback
- Timing
Delayed clamping of cord for 30-60 seconds or until
pulsation stops is beneficial
¡ Less iron deficiency anemia
¡ Less intraventricular hemorrhage of preterm infants
Drawback: higher degree of jaundice (1/3 fetal blood still in placental circulation)
Outline the Apgar scores and classes
Interpretation
Scored at 1st and 5th minutes of life
¡ ≥7 normal
¡ ≤3 abnormal
¡ Poor AS associated with neonatal mortality
¡ Poor late AS associated with poor neurological outcome
No need to wait for 1st minute score if resuscitation is needed immediately
Routine postnatal care
Outline care plan
Early skin-to-skin contact
¡ Facilitate early breastfeeding experience
¡ Keeping warm
Temperature regulation: Normal temperature
- Skin: 36.0 – 36.5C
- Rectal (core): 36.5 – 37.5C
- Plastic wrap for pre-term infants
- Incubator care for first hours when baby is nursed naked under observation
Causes of newborn hypothermia
Temperatures that cause lowest metabolic rate in babies
Temperature difference for preterm or low weight babies
Newborn babies are prone to excessive heat loss
¡ “wet” at birth
¡ high surface area to body mass ratio
¡ little insulating fat in preterm/IUGR
¡ little reserves
¡ hypotonic posture in preterm
Thermoneutral zone: temperature range that must be maintained after birth for lowest metabolism rate
Preterm/ low weight: require higher temperature for thermo-neutral zone
Consequences of excessive heat loss and hypothermia
Fluid requirement in newborn
Fluid level changes after birth
Water makes up 75% of body weight in term infant; 85-90% in preterm infants
Physiologic contraction of ECW after birth – diuresis
- 5-7% body weight loss for term infants
- 10% body weight loss for preterm infants
- More weight loss than above ranges require review of feeding
Daily fluid intake
- Follow “normal” breast milk production
- 30-60ml/kg/day
- Increase to 150-160ml/kg/day at the end of the first week
Cord care in newborn
- Outline care plan
- List cord complications
- Cord clamping
- Clean with cool boiled water/ antiseptic solution a few times per day
- Wait for cord is dislodge by 14 days
Complications:
- True knot over cord
- Patent urachus communicating with bladder: allantoid cyst containing urine
- Umbilical granuloma: remnant of umbilical tissue with discharge
- Patent vitelline duct communicating with bowel
- Omphalitis: infection treated with IV Abx
Routine newborn screening plan
Biochemical Screening – umbilical cord blood
- G6PD deficiency (incidence 4.4% in male; 0.5% in
female)
- Thyroid function (TSH) (congenital hypothyroidism -incidence1: 2000-3000)
Universal newborn hearing screening +/- BAEP for work-up investigation
Newborn screening for inborn errors of
metabolism – dried blood spots
- Including 26 inherited metabolic diseases
- e.g. SCID, SMA screening
Newborn prophylaxis plan
IMI vitamin K at birth
- prophylaxis against vitamin K deficiency bleeding (VKDB) of newborn (previously called hemorrhagic disease of newborn)
Immunizations
- HBV at birth (+HBIG if mother is HBsAg
carrier)
- BCG before hospital discharge continue routine immunization program at
- MCHC /private sector
Ophthalmia prophylaxis in some countries (not routinely performed in HK)
- Gonococcal conjunctivitis/ chlamydia trachomatis causing blindness
- Prophylaxis with silver nitrate /iodine /antibiotics eye
cream
vernix caseosum
Vernix caseosa is a white, creamy, naturally occurring biofilm covering the skin of the fetus during the last trimester of pregnancy. Vernix coating on the neonatal skin protects the newborn skin and facilitates extra-uterine adaptation of skin in the first postnatal week if not washed away after birth.
Erythema toxicum is a common rash seen in full-term newborns. It usually appears in the first few days after birth and fades within a week. Up to half of all newborns will have erythema toxicum
A Mongolian spot, also known as slate grey nevus or congenital dermal melanocytosis, is a benign, flat, congenital birthmark with wavy borders and an irregular shape.
A stork bite, also known as a salmon patch, is a cluster of pink to reddish-purple blood vessels (capillaries) that appear on a newborn’s skin on the back of their head or neck. A stork bite is a type of birthmark. Stork bites are harmless and may fade over time. About 50% of adults still have stork bites.
Cephalohaematoma: does not cross suture line, usually caused by repeated compression during vaginal birth
Subapeneurotic hematoma: bleeding under aponeurosis, crosses suture line/ midline, collection of 200-300mL blood, results in anemia and shock, ears are pulled forward from normal position
Scalp edema is a benign ddx
Lymphedema is a chronic localised swelling caused due to excessive accumulation of lymphatic fluid in the interstitium and resulting from defective lymphatic drainage [1]. Lymphedema can be primary or secondary. Primary lymphedema results from developmental abnormalities leading to pathological lymphatics. Secondary lymphedema is an acquired dysfunction of normally developed lymphatics [1] [2]. Congenital subtype of primary lymphedema is defined as swelling that has an onset at birth up to two years [3]. Primary congenital lymphedema affects the lower limbs in the majority of the cases, and unilateral involvement of one of the upper limbs is a rarity
Trisomy 13 (also called Patau syndrome) is a genetic disorder in which a person has 3 copies of genetic material from chromosome 13, instead of the usual 2 copies. Rarely, the extra material may be attached to another chromosome (translocation).
Symptoms include:
* Cleft lip or palate
* Clenched hands (with outer fingers on top of the inner fingers)
* Close-set eyes – eyes may actually fuse together into one
* Decreased muscle tone
* Extra fingers or toes (polydactyly)
* Hernias: umbilical hernia, inguinal hernia
* Hole, split, or cleft in the iris (coloboma)
* Low-set ears
* Intellectual disability, severe
* Scalp defects (missing skin)
* Seizures
* Single palmar crease
* Skeletal (limb) abnormalities
* Small eyes
* Small head (microcephaly)
* Small lower jaw (micrognathia)
* Undescended testicle (cryptorchidism)
common reason for congenital clouding of the cornea is congenital glaucoma
Other major causes of corneal clouding include the following:
* Birth trauma
* Peters anomaly
* Dermoid tumors (limbal dermoids)
* Sclerocornea
* Congenital hereditary endothelial dystrophy (CHED)
* Mucopolysaccharidoses
* Infectious/inflammatory processes
Hirschsprung’s disease (also called congenital aganglionic megacolon) occurs when some of your baby’s intestinal nerve cells (ganglion cells) don’t develop properly, delaying the progression of stool through the intestines.
Imperforate anus or anal atresia is a congenital anorectal malformation (ARM) where a normal anal opening is absent at birth. ARMs comprise of a broad spectrum of defects ranging from minor (e.g., membranous covering) to complex cloacal malformations involving the urinary and genital tracts as well.
Picture: Anal atresia with fistula formation
Hypospadias is a birth defect in boys in which the opening of the urethra is not located at the tip of the penis. In boys with hypospadias, the urethra forms abnormally during weeks 8–14 of pregnancy.
Outline exam of spine and hip in newborn
Back and spine
- Spina bifida, swellings, tethered cord
- Stigmata of underlying spinal defect –midline dimples, mass, tufts of hair, haemangioma
- Deformities e.g. scoliosis
Hips
- Developmental dysplasia of the hip (DDH)/ congenital dislocation of the hip/ hip dysplasia: hip joint attaches the thigh bone (femur) to the pelvis
- Screen with Ortolani and Barlow tests: dislocate and relocate hip
Erb’s palsy
The infant’s arm hangs limply from the shoulder with flexion of the wrist and fingers due to weakness of muscles innervated by cervical roots C5 and C6. Risk factors are macrosomia (large baby) and shoulder dystocia. However, Erb’s palsy may occur following cesarian section.
An easy way to test for this is to check for the Moro reflex (or startle reflex), a natural response present immediately after birth, which disappears by three to four months of age.
