physiological basis of resuscitation at...
TRANSCRIPT
Physiological basis of resuscitation at birth
NLS 2016
Learning outcomes
• A basic understanding of the physiology of birth asphyxia provides a logical approach to resuscitation
• It explains why we do what we do, and the importance of order in which we do it
NLS 2016
Adults havecardiac arrests
Children have respiratory arrests
NLS 2016
Important Factor affect breathing at birth
• Small
• Wet
• Lungs full of fluid
NLS 2016
At birth – Babies…
• Are prone to hypothermia
• have unexpanded lungs
• take 10 min for O2 saturation to reach 90%
• have capacity for agonal gasping breaths
• have high cardiac glycogen stores
NLS 2016
Stimuli for the first breath
• Cord obstruction
• Temperature change
• Physical stimulation
NLS 2016
What happens with the first breaths?
NLS 2016
Push fluid from airway and alveoli
First breaths
Establish
resting lung volume
NLS 2016
Aeration of the lungs
NLS 2016
0.3 sec0.0 sec 0.6 sec
Lind J. Initiation of breathing in the newborn infant. J Ir Med Assoc 1962 Apr;50:88-93
Radiographs of first breath
Response to hypoxia
• Animal experiments – Fetal lamb
- Breathing changes
- Level of consciousness
- Blood pressure
- Heart rate
- PO2 / PCO2
NLS 2016
10 30 40
Pa O2
minutes
© Northern Neonatal Network
160
120
80
40
00
Breaths
20
Primaryapnoea
Terminalapnoea
Respiratory center Normal breaths (but
suppressed spinal center stimulation
Spinal center stimulation Gasping breaths
10 30 40
Pa O2
Pa CO2
Heart rate
minutes
© Northern Neonatal Network
Blood Pressure
160
120
80
40
00
Breaths
20
During Primary apneoa circulation is
maintained – By shutting down
circulation to non essential areas
If the baby cannot breath
Inflate the lungs
NLS 2016
10 30 40
Pa O2
Pa CO2
Heart rate
minutes
© Northern Neonatal Network
Blood Pressure
160
120
80
40
00
Breaths
Birth
If no intervention, what will
happen? – Baby will die
10 20 30 40
Pa O2
Pa CO2
Heart rate
minutes
© Northern Neonatal Network
Blood Pressure
160
120
80
40
00
Breaths
Birth
LungAeration
Ventilation
Chest compressions
Primaryapnoea
Terminalapnoea
Understanding thephysiology is vital
NLS 2016
In Summary
• Primary apnoea and secondary apnoea
• Physiological changes in both
• Appropriate interventions
NLS 2016
10 20 30 40
Pa O2
Pa CO2
Heart rate
minutes
© Northern Neonatal Network
Blood Pressure
160
120
80
40
00
Breaths
Birth
LungAeration
Ventilation
Chest compressions