'Kids are not small adults ' you will hear it many many times during your pediatric rotation nonetheless great care is needed when caring for young patients
1. Airway:
Epiglottis is floppy and is described as omega shaped, institutes routinely use straight blades(miller) to lift the epiglottis to help in intubation. I found it helpful to insert the blade move tongue to the left and elevate the epiglottis and to slowly withdraw till one sees vocal cords.
Head is large relative to body size so in neonates one may have to put some blankets below the shoulders and only a small ring may be placed below head without elevating head the head is naturally placed in sniffing position
The ventilatory response to hypercapnia is blunted in infants
Hypoxia stimulates respiration
The tongue is large relative to oral cavity
Cricoid is the narrowest part of airway(subglottic) so even if a tube passes easily via vocal cords may get stuck at the level of cricoid so don't forced tube use small size tube
Be very gentle because mucosal edema will narrow the airway to a greater relative extent compared to adults
Tube size= 4+ age/4 reduce .5 size smaller if cuffed tube. Always keep .5 size smaller and .5 size larger.
If using cuffed tube inflate the cuff to ensure the leak just disappears at 20 cm pressure.
Depth - nothing replaces careful auscultation ensuring bilateral breath sounds, however as a rough
guide after 2 year Depth = 12 + age/2
FRC is very close to closing capacity that combined with high oxygen requirement7cc/kg means infants desaturate rapidly
The ribs are horizontal compared and accessory muscles of respiration are poorly developed with diaphragm being the main muscle.
Larynx is more cephalad @ C 3-4
Normal respiratory rate is 35 in neonate
2. Cardiac: both ventricular walls are of same thickness opposed to adults where left ventricle is thicker than right
There is poor lusitrophy and ventricles are relatively stiff so cardiac output is greatly preload
dependent
The sympathetic system is less developed so spinal anesthesia does not produce as much hypotension. Parasympathetic stimulation is well developed so infants respond to noxious stimulation by bradycardia.
Normal heart rate in 120-160 in newborn, 105-135 by 1 yr of age 85-105 by 5 yr age
Systolic Bp is 60-65 in neonate, 90-100 by 1 yr age and and100 by 5 yr of age.
Blood volume is 85ml/kg in full term neonate and 80ml/kg in infants.
Hb at birth is 18-20 g/dl which decreases to 10 g/dl by 10 weeks of life in full term neonate
EKG- at birth the thickness of right ventricle is same as left ventricle so in children EKG shows t wave inversion in leads V1-V3 with RBBB till 8 yr age
BOTH CARDIAC OUTPUT AND VENTILATION ARE RATE DEPENDENT(heart rate and respiratory rate respectively)
3. CNS
Increases proportion of water in brain , blood brain barrier is immature
Increased MAC which is maximum in infants (3.5 for Sevoflorane)
Separation anxiety starts at 6 months
1. Airway:
Epiglottis is floppy and is described as omega shaped, institutes routinely use straight blades(miller) to lift the epiglottis to help in intubation. I found it helpful to insert the blade move tongue to the left and elevate the epiglottis and to slowly withdraw till one sees vocal cords.
Head is large relative to body size so in neonates one may have to put some blankets below the shoulders and only a small ring may be placed below head without elevating head the head is naturally placed in sniffing position
The ventilatory response to hypercapnia is blunted in infants
Hypoxia stimulates respiration
The tongue is large relative to oral cavity
Cricoid is the narrowest part of airway(subglottic) so even if a tube passes easily via vocal cords may get stuck at the level of cricoid so don't forced tube use small size tube
Be very gentle because mucosal edema will narrow the airway to a greater relative extent compared to adults
Tube size= 4+ age/4 reduce .5 size smaller if cuffed tube. Always keep .5 size smaller and .5 size larger.
If using cuffed tube inflate the cuff to ensure the leak just disappears at 20 cm pressure.
Depth - nothing replaces careful auscultation ensuring bilateral breath sounds, however as a rough
guide after 2 year Depth = 12 + age/2
FRC is very close to closing capacity that combined with high oxygen requirement7cc/kg means infants desaturate rapidly
The ribs are horizontal compared and accessory muscles of respiration are poorly developed with diaphragm being the main muscle.
Larynx is more cephalad @ C 3-4
Normal respiratory rate is 35 in neonate
2. Cardiac: both ventricular walls are of same thickness opposed to adults where left ventricle is thicker than right
There is poor lusitrophy and ventricles are relatively stiff so cardiac output is greatly preload
dependent
The sympathetic system is less developed so spinal anesthesia does not produce as much hypotension. Parasympathetic stimulation is well developed so infants respond to noxious stimulation by bradycardia.
Normal heart rate in 120-160 in newborn, 105-135 by 1 yr of age 85-105 by 5 yr age
Systolic Bp is 60-65 in neonate, 90-100 by 1 yr age and and100 by 5 yr of age.
Blood volume is 85ml/kg in full term neonate and 80ml/kg in infants.
Hb at birth is 18-20 g/dl which decreases to 10 g/dl by 10 weeks of life in full term neonate
EKG- at birth the thickness of right ventricle is same as left ventricle so in children EKG shows t wave inversion in leads V1-V3 with RBBB till 8 yr age
BOTH CARDIAC OUTPUT AND VENTILATION ARE RATE DEPENDENT(heart rate and respiratory rate respectively)
3. CNS
Increases proportion of water in brain , blood brain barrier is immature
Increased MAC which is maximum in infants (3.5 for Sevoflorane)
Separation anxiety starts at 6 months
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