Oxygenation in High Risk Newborns

Preterm newborn

Born after 20 weeks and before 38 weeks gestation.

Decisions about resuscitation efforts are based on gestational age and sometimes weight of the newborn. 

Grey zone

22 weeks gestation.

Resuscitation decisions during this time are not clear cut.

Pulmonary complications

Most critical physiologic adaptation for preterm infants

Pulmonary complications reasons

Surfactant: Decreased before 28 weeks, uses more energy 

Alveoli unable to fill and assist in oxygenating vascular bed

Weak musculature: Decreased strength in their diaphragm and intercostals, decreases muscle control in their blood vessels

Pulmonary complications result in…

Respiratory Distress Syndrome (RDS)

Respiratory Distress Syndrome presentation

• Grunting

• Flaring 

• Retractions

• Tachypnea

• Cyanosis

• Diminished breath sounds

• Hypoxic 

RDS pharmacological treatments

Surfactant - Curosurf

Betamethasone or Dexamethasone

Curosurf (poractant alfa)

Type of surfactant that is given after the baby is born through the endotracheal tube

Betamethasone/Dexamethasone

Steroid to speed up surfactant production, decreases brain bleeds and necrotizing enterocolitis

RDS non pharmacological support

Ventilation: Skin to skin is encouraged when possible

Apnea of prematurity

Infant stops breathing for periods of time > 20 seconds likely due to less developed neuro system and weak airway muscles.

Will see drops in the heart rate and hypoxia as a result.

Apnea of prematurity treatments

Stimulation

Caffeine: Given PO or IV, used to decrease periods of apnea

Patent Ductus Aterious (PDA)

Incomplete constriction of the duct due to decreased oxygen.

This affects respiratory status by increasing oxygen needs and causing need for increased ventilator settings.  Persistent heart murmur audible.

PDA treatments

• First: Watchful waiting

• If no closure: 

  • NSAIDS

  • Endomethycine

  • Surgical intervention

Neuroprotection

Administer MgSO4 to mother to help prevent cerebral palsy in preemies at birth.

(What else is it administered for? to stop preterm labor, preeclampsia)

Mag Sulfate treatment criteria

Gestational age > 23 but less than or equal to 31 6/7 weeks

Singleton or multiple pregnancy at risk for delivery within the next 30 mins to 24 hrs

Mag Sulfate administration

• IV loading dose: 4-6 g / 30 mins

Hourly rate: 2g/hr

Mag Sulfate assessments

Watch for signs of hypermagnesia which include:

Lethargy

Hypotonia

Poor suck

Decreased or absent reflexes

Increased respiratory distress

Periods of apnea

Small for gestational age

Infant whose birth weight is at or below the 10^th percentile

SGA oxygenation

Fetal hypoxia or perinatal asphyxia caused by decreased placenta functioning. Placenta tends to be smaller as a result of decreased perfusion from vasoconstriction caused by:

HTN, preeclampsia, smokers, polycythemia

Polycythemia

chronic intrauterine hypoxia increases RBC production leads to increased blood volume & elevated H&H 

(Hct >65% - normal is 51-56%, Hgb >22g/dL – normal is 14-20g/dL)

Polycythemia symptoms

Redness, tachycardia, CHF, respiratory distress syndrome, seizures

Polycythemia goals/treatment

Goal is to decrease Hct to normal levels - often this occurs naturally with time

Treatment – Partial Exchange Transfusion – only if necessary

Large for gestational age

Infant whose birth weight is at or above the 90^th percentile

LGA oxygenation

Oxygenation issues these infants experience may have to do with their size (often macrosomic > 4,000grams) and the maternal process (DM) that caused the accelerated growth or the difficulties a large size has on vaginal delivery

Infants of diabetic mothers

• Often LGA, but can also be SGA

  • Hypoglycemia – Trouble controlling blood sugars because they had high insulin levels in utero, resolves in 24 hrs

The work of trying to regulate the low blood sugar can cause respiratory distress. 

LGA complications

Shoulder dystocia - Head is delivered, but shoulder gets stuck

Transient tachypnea of the newborn (TTN) – increased risk in LGA babies due to higher C-section rates. (Also more common in pre-term infants – 34-37 weeks) Leftover fluid in the lungs, inadequate clearing of the airways, increased work of breathing, GFRs, temporary 24-48 hours

Post maturity

Born after 42 weeks gestation

Morbidity rates increase

Post maturity general appearance

Long and thin, head appears large, skin thick & peeling, long fingernails and may have meconium stained fluid, yellow skin color

Post maturity oxygenation

Fetal hypoxia/perinatal asphyxia due to lack of oxygen from decreased placental functioning. Remember placenta has a shelf life – expiration date. 

Meconium aspiration syndrome (MAS)

Meconium aspiration syndrome (MAS)

• Asphyxia in utero can cause increased peristalsis of intestines, relaxation anal sphincter, and passage of meconium in amniotic fluid.

• Meconium is a thick material that can be inhaled into the distal airways in utero or with the first gasp of air.  

• The thickness of meconium causes a ball-valve effect in the alveoli, trapping air in the alveolus creating distension and preventing adequate gas exchange.

Pneumothorax is a major complication as alveoli over distend, rupture, and air enters into the pleural space. 

Pneumothorax S&S

Sudden and acute respiratory distress, cyanosis/pallor, diminished breath sounds on affected side, asymmetrical chest expansion

Pneumothorax care

Chest tube

Oxygen 

Auscultate breath and heart sounds

Asphyxia

Perinatal asphyxia results from deprivation of oxygen to the fetus during the birth process that causes physical harm, usually to the brain.

Apgar’s can be reflective of the severity of asphyxia

Mild asphyxia

Apgar 5-7

Moderate asphyxia

Apgar 3-4

Severe asphyxia

Apgar 0-2

Code pink

Neonatal Resuscitation Program (NRP)

Resuscitation using algorithm

10% of newborns need some type of resuscitation with only 1% needing a full code