Good Things Come in Small Packages: Unique Neonatal/Infant Features

Outline

1. Abusive head trauma
2. Traumatic thoracic injuries
3. Congenital diaphragmatic anomalies
4. Abdominal effects upon respiratory system

Abusive Head Trauma (AHT)
Formerly known as “Shaken Baby Syndrome”
First described in 1974 by Dr. John Caffey
Injuries include:

• Subdural hematoma
• Long bone fractures
• Retinal hemorrhages
• Posterior rib fractures

Injury results from:

• Impact
• Acceleration-Deceleration

Acceleration-Deceleration
Anatomic features increase susceptibility

• Large head in relation to body
• Inadequately supported head
• Weak neck muscles

Results in vigorous movements of intracranial contents
Shear forces result in diffuse axonal injury (DAI) and subdural hemorrhage
DAI leads to cerebral edema

ABUSIVE HEAD TRAUMA IN CHILDREN

Impact

• Most children who suffer fatal abusive head trauma also have an impact injury
• Often the constellation of injuries are from impact and acceleration-deceleration

Outcomes
30% of victims die from AHT
Survivor suffer:

• Motor deficits
• Sensory deficits
• Epilepsy
• Pound for pound, Neuro injuries in this age group have a poorer recovery because the brain cannot adapt or recruit healthy neurons (in a brain that has not as yet been exposed to learning/memory)

Chest Trauma
Children develop serious injuries without external signs
Most common injuries include:

• Pulmonary contusions
• Rib fractures
• Pneumothorax

Blunt trauma responsible for 80 to 85% of pediatric thoracic injuries

MECHANISM OF PEDIATRIC TRAUMA

Final Diagnosis & Mortality
Chest Trauma
More compliant chest wall due to incomplete ossification and higher cartilage

• Energy is transferred to underlying structures
• Rib fractures are rare

Chest trauma only represents 15% of Peds Trauma overall, but has a relatively high mortality
Due to elasticity of the mediastinum- leads to displacement of:

• Lung
• Tracheobronchial tree
• Vascular structures

Pulmonary contusion leads to

• Hemorrhage
• Edema
• Consolidation

PEDIATRIC THORAX

CDH

• Prenatal dx more common
• If dx’d before 14 weeks- prognosis poor

Diaphragmatic Development

• Diaphragm develops around week 5 of fetal life
• Pleuroperitoneal canals remain open until about 8 weeks
• Two main defects- Bochdalek and Morgagni
• Frequently diagnosed prenatally

PEDIATRIC THORAX

Post-natal Rx of CDH

• Honeymoon period
• Intubate stomach first, try to delay on positive pressure
• ECMO/NO/OSCIL-LATOR RX may be critical to survival

Respiratory Failure
Abdominal defects once repaired lead to increased intraabdominal pressure
Pulmonary function can decline from increased intraabdominal pressure

• Diaphragm is elevated and flattened
• Abdominal muscles limited in ability to move diaphragm

Diaphragm is the major muscle of respiration- stoked by abdominal wall
Intraabdominal pressure is raised after treatment of

• Gastroschisis
• Omphalocele
• Congenital Diaphragmatic Hernia

Abdominal Wall Defects- Major Developmental- Omphalocele vs Gastroschisis