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)
Median nerve supplies all motor in flexor compartment except
- Thenar compartment
- 2x Lumbricals (LOAF)
EXCEPT FCU and medial half of FPD
Erbs vs Klumpkes palsy
E before K
Erbs = upper brachial plexus C5-6, porters tip hand, adducted/medialy rotated, pronated/externally rotated
- affects deltoids, biceps, brachialis,
Klumpkes = lower brachial plexus C8-T1
- Claw hand- intrinsic hand muscles/ulnar flexors weak, unopposed
- +/- Horners, vasoactive changes
What nerve supplies anatomical snuffbox sensation
Radial
What muscles does the ulnar nerve supply?
Medial 2 lumbrical = flex the MCP, extend the IP joints of little + ring fingers
Interossei = abduct and adduct the fingers
Hypothenar muscles
Adductor pollicis
When does a childs eGFR reach adult levels (per equivalent BSA)?
2 yrs
Example of ‘two hit hypothesis’ in paediatric cancers?
Retinoblastoma
two mutations (two hits) of key genes in the control of cell division occurring in a retinal neuro-ectodermal cell were necessary for the development of retinoblastoma
What is the main advantage of whole genome sequencing when compared to whole exome sequencing?
Intrinsic mutations are detected
Most common injury in NAI?
Metaphyseal corner fracture
Which cells produce Anti-Mullerian Hormone?
Sertoli cells
Say no to mother
Mechanism of action of Sildenafil?
cGMP-specific phosphodiesterase inhibitor
Mechanism of action of Sildenafil?
cGMP-specific phosphodiesterase inhibitor
Management of EPSE with metaclopramide (oculogyric crisis)
Benztropine (anti-cholinesterase)
What gene is responsible for the cardiovascular phenotype in Williams syndrome?
ELN
‘Elvin Facies’
Blood findings in C1Einh/HAE?
Low C4, low C1-esterase inhibitor level, low C1-esterase inhibitor function
Which CSF metabolite is the most sensitive marker of inflammation?
Neopterin
Which autoinflammatory condition is associated with a gene defect in pyrin?
Familial mediterranean fever
‘Family festive pyre = pyrin’
What anti-epileptic drug demonstrates irreversible inhibition of GABA transaminase?
Vigabatrin
What is the term for the point of maximal absorption of a solute by the renal tubule?
Transport maximum
What protein is affected in NMO?
Aquaporin 4
What cell type accounts for increased immunity provided by conjugated pneumococcal vaccines in comparison to un-conjugated pneumococcal vaccines?
CD4
Where does the oesophagus originate from? What is its length at birth, when does it reach adult length?
Post-pharyngeal forgut
Length of esophagus is 8-10 cm at birth and doubles in the first 2-3 years of life to reach 25cm in adult
When is swallowing first seen?
Swallowing seen as early as 16-20 weeks in utero
-Polyhydramnios is the hallmark of lack of normal swallowing or esophageal upper GI obstruction
What are the landmarks surrounding the oesophagus?
Relation to adjacent structures
Prevertebral fascia posteriorly
Trachea/ L mainstem bronchus/ heart anteriorly
Fixed at origin
Mobile throughout mediastinum
Structure of stomach? Innervation?
Wall: mucosa>submucosa>muscularis>serosa
Epi: simple columnar
2x sphincters:
- LES (smooth muscle)
- pyloric (allows passage into duodenum once fluid consistency- ‘chyme’)
Stomach is surrounded by parasympathetic (stimulant) and sympathetic (inhibitor) plexuses which regulate both the secretions activity and motor activity of the muscles
Interstitial cells of Cajal are specialised pacemaker cells located in the wall of the stomach, small intestine and large intestine – responsible for migrating motor complex which result in waves in peristalsis
The epithelium and lamina propria are by tubular glands
Cells in stomach- what hormones/enzymes released?
Oxynctic/parietal cells: HCL (upper stomach)
Chief cells: pepsinogen (activated by HCL, deactivated alakaline in duodenum)
Enterochromaffin like cells: histamine (lower stomach)- regulate digestive hormones
G cells: gastrin
Mucous cells: mucus