Phys/Anat facts Flashcards
Where is EPO produced in the neonate
The liver is the predominant site of erythropoietin secretion in the fetus. In adults and children, the kidney is the main site.
What nutrients are absorbed in the duodenum
Ions! calcium, magnesium, phosphate
+ iron, folic acid.
What nutrients are absorbed in the proximal 100-200cm of small intestine:
CHO, protein, water-soluble vitamins
What nutrients are absorbed throughout small intestine
monoglycerides and fatty acids as micellar complexes; medium chain TG directly into the portal circulation.
What nutrients are absorbed in the distal ileum
B12, bile acids, Ca2+
How is Ca2+ absorbed through the gut?
- Duodenum and upper jejunum: active vitamin D-dependent transport (more efficient, less Ca
- Ileum: passive vitamin D-independent, paracellular diffusion (less efficient, more Ca).
Vitamin A deficiency – symptoms
ocular signs known as xerophthalmia, of which the earliest sign is night blindness.
Vitamin D deficiency – symptoms
.
rickets, hypocalcaemia, hypophosphataemia.
Vitamin E deficiency –symptoms
tocopherol (vitamin E) deficiency can be associated with a progressive sensory and motor neuropathy (proprioreceptive), spinocerebellar ataxia, retinal degeneration (pigmented retinopathy and loss of vision), and a haemolytic anaemia.
Vitamin K deficiency –symptoms
bleeding diathesis
What influences the magnitude of L>R shunt in ASD?
Size of defect + RV/LV compliance
What causes 3rd heart sound
Rapid ventricular filling- volume overload conditions
What part of the heart does pulmonary wedge pressure (5-12mmHg) approximate?
Indirect measure of the mean left atrial pressure. A catheter (e.g. Swan-Ganz catheter) is floated through the right heart into a branch of the pulmonary artery and the balloon is inflated, occluding the artery and blocking the incoming flow of blood. The tip of the catheter, which lies beyond the balloon, is connected to a pressure transducer. As this column of blood is connected to the left atrium via a bed of pulmonary capillaries and pulmonary veins, the pressure measured by the catheter tip will reflect the distal LA pressure (normally 5-12 mmHg).
What part of the heart does pulmonary wedge pressure (5-12mmHg) approximate?
Indirect measure of the mean left atrial pressure. A catheter (e.g. Swan-Ganz catheter) is floated through the right heart into a branch of the pulmonary artery and the balloon is inflated, occluding the artery and blocking the incoming flow of blood. The tip of the catheter, which lies beyond the balloon, is connected to a pressure transducer. As this column of blood is connected to the left atrium via a bed of pulmonary capillaries and pulmonary veins, the pressure measured by the catheter tip will reflect the distal LA pressure (normally 5-12 mmHg).
When do the paranasal sinuses develop/become pneumatized?
Birth- only ethmoidal sinuses are pneumatized
Maxillary sinuses are not pneumatized until 4 years of age
Sphenoidal sinuses present by age 5, frontal sinuses develop at age 7-8
What is the narrowest component of the upper airway in infants
Subglottis
What is FEF25-75 used to measure
FEF25-75 (maximum mid-expiratory flow rate) = flow in smaller airways, most effort dependant portion of curve, measures milder obstruction.
Patterns on spirometry with obstructive (extrathoracic & intrathoracic, fixed & variable) diseases
Obstruction- ↓ FEV1, N FVC, ↓ FEV1/FVC ratio
- Bronchodilator response: >12% change in FEV1 dx
- Provocation test: >15-20% change methacholine, histamine, saline
Fixed obstruction- flattening of curve both insp & exp
- glottic/subglottic lesion
Variable extrathoracic obstruction: flattening only on INSPIRATION (curve is upper)
- laryngeal/tongue pathology
Variable intrathoracic obstruction: flattening only on EXPIRATION (curve is lower)
- bronchomalacia/lower tracheal pathology
Sawtooth pattern- neuromuscular disease
Small hump in loop-
Patterns on spirometry with restrictive disease
Restrictive ↓FEV1, ↓FVC, N FEV1/FVC ratio
Patterns on spirometry with poor technique, cough- operator effects
Define normal sleep phases/cycle
Cycles 90-120min
- Infants 40mins
- Young children 50-60mins
- NREM (stage 1-4)
Stage 1 lightest
Stage 2 intermediate sleep 40-50% total sleep time
Stage 3 and 4 deep/restful sleep (20% time) - REM sleep = Rapid Eye movement
20% of adult sleep, 50% of infant sleep
- Low muscle tone, decreased TV/irregular breathing
- Nightmares/dream
- Consolidation of memory/plasticity
Define stages of sleep/normal durations
Normal napping
1 year old 2 naps per day
2 year old 1 nap per day
5 year old No napping
Normal sleeping
Approximate = 16 – age (only from birth to sleep time 9hrs, stable in adolescents)
Birth 16 hours
2 years 14 hours
6 years 10 hours
18 years 8 hours
Adult 7 hours
What are common changes to sleep patterns with age
There is a gradual decline in the average 24 hour sleep duration from infancy through adulthood
Average adolescent still requires 9-9.25 hours of sleep per night
Naps typically cease at age 5 years
Decline in the relative percentage of REM sleep from birth (50%) to early childhood into adulthood (25-30%)
SWS – peaks in early childhood, drops off abruptly after puberty, and then further decreases
Why is NO administered via ETT as close to patient as possible?
NO is usually fed into the ventilator tubing as close to the patient as possible, limiting the mixing time between O2 and NO- forms toxic compounds i.e NO2 (can damage resp tract)
