Neonatology Flashcards
(39 cards)
What is the definition of preterm? Define the different levels of severity.
Preterm: babies born alive <37 weeks of gestation
- Moderate-late preterm: 32-37 weeks
- Very preterm: 28-32 weeks
- Extremely preterm: <28 weeks
(According to the lecture, extreme prematurity = <30 weeks)
It is for this reason that induction of labour or C/S should not be planned <39 weeks unless medically indicated to prevent iatrogenic prematurity.
What is the definition of low birth weight? Define the levels of severity.
- Low birth weight (6%): <2500g
- Very low birth weight (1%): <1500g
- Extremely low birth weight (<1%): <1000g
What is the definition of term?
37-42 weeks of maturity
What are the factors of PPROM?
- *Maternal**
- Ascending infection
- Cervical incompetence
- Smoking
- *Fetal**
- Polyhydramnios
- Breech
What are the risk factors for preterm labour?
- *Maternal factors**
- Maternal age <15 yeras of >40 years
- Low body weight
- History of preterm delivery
- Primigravida
- Pre-eclampsia
- Extra-uterine infections
- Social causes: alcohol, smoking, drugs, domestic violence, stress etc.
Pregnancy-related factors
- Uterus
>> Overdistension from fibroids, multiple gestation or polyhydramnios
>> Uterine abnormalities
>> Uterine trauma
- Membranes
>> Chorioamnionitis
>> PPROM
- Placenta
>> Abruptio
>> Previa
- Fetus
>> Multiple gestation
>> Chromosomal abnormalities
>> Congenital abnormalities
- Cervix
>> Cervical incompetence
>> Cervical trauma/surgery
What are the risk factors for chorioamnionitis?
- PPROM
- Prolonged rupture of membranes (>24 hours)
- Preterm labour with or without ROM
- GBS carriage of the mother
- Bacterial vaginosis of the mother
What are the complications of prematurity to the baby?
Acute complications
- Respiratory
>> Respiratory distress syndrome
>> Apnea of prematurity
>> Pneumothorax
- Patent ductus arteriosus
- Necrotizing enterocolitis
- Intraventricular hemorrhage
- Hypoglycemia, hypocalcemia and electrolyte disturbances
- Hypothermia
- Dehydration
- *Chronic complications**
- Bronchopulmonary dysplasia
- Retinopathy of prematurity (ROP)
- Post-NEC complications: short bowel syndrome
- Periventricular leukomalacia >> quadriplegic cerebral palsy
- Post-hemorrhagic hydrocephalus
- Developmental delay
- Osteopenia of prematurity
What is the presentation of respiratory distress syndrome?
Features of respiratory distress (tachypnea >60, tachycardia, nasal flaring, expiratory grunting, use of accessory muscles, intercostal and subcostal insucking) within 4 hours of delivery with difficulty waning off oxygen
What are the typical CXR findings of RDS?
- Ground-glass appearance of fine reticular, homogenous shadows
- Hazzing out of the cardiac shadow
- Air bronchogram
How does one manage a case of RDS?
- Stabilize the patient: ABC, fluid resuscitation if necessary
- Look out for anemia and malnutrition
- Nasal CPAP
-
IPPV/HFOV (intermittent positive pressure ventilation, high frequency oscillation ventilation)
>> Prolonged and frequent apnea
>> Severe hypoxemia
>> CO2 retention
>> Respiratory fatigue - Surfactant replacement with exosurf VS. survanta
>> Maternal steroids given 24-48 hours prior to delivery helps prevent RDS
Most patients with ?RDS also receive antibiotics since congenital pneumonia and RDS are clinically and radiologically indistinguishable.
What is necrotizing enterocolitis?
Intestinal inflammation associated with focal or diffuse ulceration and necrosis, primarily affecting the terminal ileum and colon
Mucosal damage and enteral feeding –> bacterial growth –> bowel necrosis, gangrene and perforation
What are the risk factors for NEC?
- Prematurity
- Enteral feeding with formula (breast milk can be protective)
- Asphyxia, shock, sepsis
How does NEC present?
- Poor feeding
- Bile-stained vomiting
- Frank/occult blood in stool
- Abdominal distension
- Diminished bowel sounds
- Signs of bowl perforation
>> Peritonitis
>> Shock
>> DIC
>> Sepsis
What are the typical AXR findings for NEC?
- Intramural gas: pneumatosis intestinalis
- Distended bowel loops
- Fixed bowel loops
- Thickened bowel wall
- Portal tract gas
- Free gas (“Football sign”)
How does one manage a case of NEC?
- *Prevention in pre-emies**
- Cautious feeding regime
- Breastfeeding
- Early treatment for PDA and polycythemia
Treatment
- NPO with parenteral nutrition
- Vigorous IV fluid resuscitation
- Decompression with NG tube
- Antibiotics
>> Ampicillin, gentamicin +/- metronidazole x 7-10 days)
- Supportive ventilation and circulation
- *- Serial AXRs to detect early perforation**
- Surgical resection of necrotic bowel, perforation and strictures
- *Possible complications**
- Intestinal obstruction
- Short gut syndrome
What is intraventricular hemorrhage?
Hemorrhage in the periventricular subependymal germinal matrix, usually occurring within 72 hours of delivery
How common is RDS?
14% of all LBW infants
How common is IVH?
~25% of lal LBW infants
What are the risk factors for IVH?
- Prematurity <32 weeks
- BW <1500mg (very low birth weight)
- Need for vigorous resuscitation at birth
- Pneumothorax
- Respiratory distress syndrome
- Hemodynamic instability
How may IVH present?
Most are asymptomatic
- Apnea
- Bradycardia
- Altered level of consciousness
- Hypotension
- Seizures
- Acidosis
- Bulging fontanelle with separation of sutures
- Shock
What are the complications of IVH?
- *Acute**
- Post-hemorrhagic hydrocephalus
- Post-hemorrhagic infarction
- Cyst formation
- Extension of bleed
- Death
- *Chronic**
- Epilepsy
- Cerebral palsy
- Visual and hearing impairment
- Developmental delay
- Intellectual disability
Routine head USG screening for all preterm infants <32 weeks or <1500g throughout NICU stay to screen for IVH – In Canada.
What is retinopathy of prematurity (ROP)?
Vasoproliferative retinopathy
- Nasal retina vascularization completion: 36 weeks
- Temporal retina vascularization completion: 40 weeks
- Due to high oxygen exposure after birth, disrupting the vascularization process
>> The most common cause of blindness in preterm infants
>> Treatment: laser, cryotherapy
Hwo does ROP present?
- Retinal hemorrhage
- Retinal fibrosis and detachment
- Blindness
