Assessment of the Neonate
Fred Hill, MA, RRT
Reduction in Pulmonary Reserve
• Thorax is more flexible
• Heart is larger in proportion to
thorax
• Abdominal contents are larger in
proportion to thorax
Breathing and Coughing
• Newborns are “obligate nose
breathers”
• Neonates lack a cough reflex
• Smaller airways, but epithelial cells
are similar in size
• Breathing rate = 30-50 vs 12-20;
premature = 40-60
• Heart Rate = 100-140 vs 60-80
Upper Airway Anatomy
• Tongue is larger in proportion to oropharynx.
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More lymphoid tissues in pharynx.
Larynx is more anterior and higher.
Epiglottis is larger and stiffer in proportion, lies
more horizontal, omega shaped
Cricoid cartilage is narrowest portion of upper
airway (~7 years changes to glottic area)
Carina is only 4 cm below vocal cords
Tracheal diameter: 4 mm vs 16 mm
Other Considerations
• Ribs are more horizontal (not bucket
handle). Rely primarily on diaphragmatic
breathing.
• Breath sounds transmit well due to thin
thoracic wall, but harder to localize
sounds.
Newborn X Ray
Infant X Ray
Other Aspects of Newborn
• Higher metabolic rate: 100 cal/kg vs 4050 cal/kg
• Reactions to medicines not predictable
– High metabolic rate
– Immature liver and kidneys
• High surface area to body weight ratio
Gestational Age Assessment
• Dubowitz Gestational Age Assessment
– 11 physical signs
– 10 neurologic signs
– Useful in the first 5 days of life
• Ballard Gestational Age Assessment
– 6 neurologic signs
– 6 physical signs
– Before 42 hours of life (ideal 30 to 42 hours)
Ballard Gestational Age Assessment
Physical Signs
• Skin
• Lanugo
• Plantar surface
• Ear recoil
• Breast tissue
• Genitalia
Size for Gestational Age
• Two reasons for low-birth-weight infant
– Prematurity
– Growth retardation
• Size for gestational age
– Appropriate for gestational age (AGA)
– Large for gestational age (LGA)
– Small for gestational age (SGA)
Weight vs Gestational Age: Boys
Weight vs Gestational Age: Girls
Signs of Respiratory Distress
• Synchrony of chest/abdomen movements
• Retractions
– Lower chest (lateral ribs)
– Xiphoid (substernal)
• Nasal flaring
• Expiratory grunting
• Cyanosis
• Tachypnea
Respiratory Care Procedures
Fred Hill, MA, RRT
Endotracheal Tube Suctioning
• Two people
– One to perform suctioning
– One to monitor and provide support as
needed
• Depth of catheter insertion determined by
length of ET tube; only to tip
• Size of suction catheter as per ETT size
• Suction pressure: -50 to -80 mm Hg
Suction Catheter Size
Endotracheal Tube
Suction Catheter
2.5
5, 6
3.0
6-8
3.5
8-10
4.0
8-10
Suction Catheter Size
Nonintubated
Suction Catheter
Preemie
5, 6
Term
6-8
Newborn to 6 months
8-10
Oxygen
• Hazards
– Retinopathy of prematurity
– Bronchopulmonary dysplasia
• Oxygen Hood (Oxyhood)
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High flow device
Usually <0.6 FiO2
Flows >7 lpm
Appropriate temperature of gas
• Cannulas: always humidified with newborns,
1/8 to 1 lpm typical flows or 0.2 to 1 lpm
Oxyhood