Peds Flashcards
Neonates
0-1 month
Infants
1-12 months
Toddlers
12-24 months
Young Children
2-12 years
Key Concept
Neonates and infants have fewer and smaller alveoli, reducing lung compliance.
Neonnates and infants have cartilaginous rib cages making their chest wall very compliant, increasing airway resistance.
Work of breathing is increased, and respiratory muscles more easily fatigue.
These characteristics promote chest wall collapse during inspiration and relatively low residual lung volumes at expiration.
The resulting decrease in FRC limits oxygen reserves during periods of apnea and predisposes neonates and infants to atelectasis and hypoxemia.
In neonates and infants, the effects of reduced FRC may be exagerrated by relatively higher rate of oxygen consumption compared to adults.
Neonates/infants: cc/kg/min
Adults: cc/kg/min
In neonates and infants, the effects of reduced FRC may be exagerrated by relatively higher rate of oxygen consumption compared to adults.
Neonates/infants: 6-8 cc/kg/min
Adults: 3-4 cc/kg/min
AIrway anatomical differences in neonates/infants?
Larger head
Shorter neck
Larger tongue
Narrow nasal passages
Obligate nasal breathers (until about 5 months)
Shorter trachea
Prominent adenoids/tonsils
Anterior/cephalad larynx (glottis at C4 vs C6 in adults)
Longer epiglottis
Waker intercostal and diaphragmatic muscles
Greater resistance to airflow
_ is the narrowest point of the airway in children younger than 5 years of age.
_ is the narrowest point of the airway in adults.
The cricoid cartiladge is the narrowest point of the airway in children younger than 5 years of age.
The glottis is the narrowest point of the airway in adults.
Neonates and infants have _ lung compliance and _ chest wall compliance.
Neonates and infants have REDUCED lung compliance and INCREASED chest wall compliance.
The cardiac output of neonates/infants is dependent on _.
The cardiac output of neonates/infants is dependent on heart rate.
Cardiac stroke volume is relatively fixed by the immature, noncompliant left ventricle in neonates and infants. The cardiac output is therefore very sensitive to changes in heart rate.
Although basal heart rate is greater in neonates and infants than adults, vagal stimulation, anesthetic overdose, or hypoxia can quickly trigger bradycardia with profound reductions in cardiac output.
The immature heart is more sensitive to depression by volatile anesthetics and to opioid induced bradycardia.
The sympathetic nervous system and baroreceptor reflex are also not fully mature. The infant cardiovascular system displays a blunted resposne to exogenous catecholamines.
What factors promote greater heat loss to the enviroment in neonates?
Think skin
Low fat content
Greater surface area relative to weight
Why are neonates predisosed to hypoglycemia?
Relatively reduced glycogen stores
NOTE:
In general, neonates at greatest risk for hypoglycemia are premature or small for gestational age, are receiving total parenteral nutrition, or had mothers with diabetes.
Total body water content of a neonate?
80%
Total body water content of an infant?
70%
Why do nneonates and infants have a faster inhalation induction than adults?
Neonates and infants have relatively greater alveolar ventilation and reduced FRC. This greater minute ventilation to FRC ratio contributes to a rapid increase in alveolar anesthetic concentration. Combined with relatively greater blood flow to the brain.
