Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Primary FRCA > Physiology > Flashcards

Physiology Flashcards

1
Q

CSF flow

A 
Lateral ventricle —>
Interventricular foramen of Munro —>
3rd ventricle —> 
Aqueduct of Sylvius —>
4th ventricle —>
Medial and lateral Foramina of Magendie and Luschka —>
Subarachnoid space
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Air embolism

A

Gold standard for detection is TOE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Blood flow during exercise

A

Blood supply to skeletal muscle increases from 1-4ml/100g/min at rest to 50-100ml/100g/min at exercise
Main mechanism is local autoregulation - hypoxia, hypercarbia, NO, K ions, adenosine and lactate
Overrides the sympathetic-driven vasoconstriction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Anterior pituitary hormones

A

Are glycoproteins which share a common ALPHA subunit and have unique BETA subunits

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Shunt in pregnancy

A

15% in lateral position

14% in supine position

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Starling forces in the lung

A

Interstitial oncotic pressure = 17mmHg
Capillary hydrostatic pressure = 13mmHg (arteriolar end), 6mmHg (venous
end)
Interstitial hydrostatic pressure = 0 to slightly negative
Capillary oncotic pressure = 25mmHg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Intracellular ions

A 
Potassium 150mmol/L
Phosphate 100mmol/L
Magnesium 20mmol/L
Sodium 15mmol/L
Chloride 10mmol/L
Calcium 100nnmol/L
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

ASA grades

A 
I = healthy, non-smoking, minimal/no alcohol consumption 
II = mild, well-controlled systemic disease without symptoms. Includes: pregnancy, BMI 30-40, smoker, social alcohol consumption, well-controlled lung disease, HTN or DM
III = moderate to severe systemic disease with substantive functional limitations. Includes BMI >40, COPD, poorly controlled HTN/DM, alcohol dependence, pacemaker, reduced EF, hepatitis 
IV = severe systemic disease that is a constant threat to life e.g. CVA/TIA/MI in past 3mths, stents, IHD, severely reduced EF, sepsis etc
V = moribund patient not expected to survive without operation 
VI = brain-dead organ donor
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

IV fluids

A 
3% NaCl - 513mmol/L Na
5% NaCl - 856mmol/L Na 
0.9% NaCl - 154mmol/L Na 
Hartmanns- 131mmol/L Na
0.45% NaCl + 5% Glucose - 77mol/L
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

TBW in neonates

A

Approx 75% of total body weight

Higher circulating volume per unit mass and lower percentage body fat than older children

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Solubility of CO2 in blood

A

Solubility factor = 0.03mmol/L/mmHg or 0.225mmol/L/kPa at 37’C
20x more soluble than O2
0.5ml/kPa in 100mls of blood = 3mls per 100mls in venous blood (PCO2 6.1kPa) and 2.5mls per 100mls arterial blood (PCO2 5.3kPa)
Henry’s Law: number of particles in solution is proportional to the partial pressure at the liquid surface
Content is higher in deoxygenated blood than oxygenated blood at a given PCO2 because reduced Hb is a better buffer of H ions as it is less acidic (Haldane Effect)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Changes in pregnancy

A

Total blood volume increases
Plasma volume increases proportionately more than red cell volume so Hb decreases
Hct and packed cell volume decrease
Increased production of T3 and T4 and TBG so plasma conc of free thyroid hormones remains constant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Changes with hypothermia

A 
Decreased insulin production so hyperglycaemia can occur 
Decreased P50 of Hb 
Increased myocardial irritability 
Decreased coagulation 
Decreased metabolic rate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Calcium

A

Normal plasma conc = 2.5mmol/L
At higher pH, plasma proteins become ionised and bind more Ca so free ionised Ca conc decreases
Extracellular, unbound Ca influences PTH secretion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Iron

A

Is bound to transferrin in its ferric form (Fe3+)
2 molecules carried per transferrin molecule
Daily loss in a man is 0.5-1mg mainly in the faeces
Iron deficiency —> hypochromic microcytic anaemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Pseudocholinesterase

A 
Found in:
Plasma 
Placenta 
Kidney
Brain 
Pancreas

Synthesised in the liver

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Rate dissociation of water

A

Is 10^-14 = [H+] x [OH-]

So [H+] is 10^-7 mol/L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Blood supply to different organs

A

Brain: 50ml/100g/min

Carotid bodies: 2000ml/100g/min

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Meissner’s corpuscles

A

Rapidly adapting cutaneous mechanoreceptors which respond to light touch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Uric acid

A

Is filtered by the glomerulus

Reabsorbed and secreted by PCT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Surgical 3rd nerve palsy

A

Causes pupillary dilatation due to compression of parasympathetic supply to pupil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

CSF composition

A

Protein conc 0.5% of plasma protein conc
Lower pH due to reduced protein buffering
Higher chloride conc to maintain electro neutrality

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Closing capacity

A

Does not change with position

But FRC increases on standing so CC less likely to encroach on FRC

24
Q

ODC

A

Shifted to the right in anaemia to facilitate offloading of O2
Cannot he used to determine oxygen carrying capacity

25
Q

Kety-Schmidt technique

A

Measures CBF using difference between arterial and venous conc of a tracer eg N2O

26
Q

Aldosterone

A

Causes water and Na retention in equal amounts so does not change urine osmolality

27
Q

Changes during exercise

A

CO increase 5-10x
Skeletal muscle blood flow increase 20-30x due to precapillary sphincter relaxation by local auto regulation
Partial pressure gradient for O2 into mitochondria increases x2
O2 offloading from Hb increase 2-3x

28
Q

SVR

A

= k (MAP - CVP) / CO

29
Q

Cardiac AP

A

Takes 0.2s to travel through atria
Conduction is slowest at the AVN
Travels between atria via Bachmann’s bundle

30
Q

Circulatory changes at birth

A

1st breath generates negative pressure of 50cmH2O
PVR falls by >80% so increased PA pressure and increased blood flow to LA
DA closes due to increased O2 levels and low PG within 24hrs
PFO fuses within 48hrs due to reversal in atrial pressures
SVR and MAP increase
Blood flow in IVC falls (due to loss of placenta blood supply)
Hypoxia, hypercarbia, acidosis and hypothermia will increase pulmonary vascular resistance and cause a right to left shunt or persistent foetal circulation

31
Q

Atrial stretch receptors

A

Type A discharge during systole

Type B discharge during diastole

32
Q

Increase in atrial pressure

A

Can increase HR via Bainbridge reflex
can decrease HR via baroreceptor reflex
Increase/decrease depends on initial HR (will decrease if high, increase if low)

33
Q

Atrial contraction

A

Right atrium contracts before left atrium

34
Q

Ventricular contraction

A

LV contracts before RV

35
Q

Afterload

A

= the tension developed in the ventricular wall during systole
Anrep effect increases SV when afterload is high by increasing LVEDV
Likely to be low in heart failure due to low intraventricular pressure
Higher in a hypertrophied ventricle because of increased radius (La Place’s Law: P = 2T/r)

36
Q

Electrolyte abnormalities and cardiac function

A

Hypokalaemia makes the membrane potential more negative so it is less excitable but has more automaticity and increases QT interval
Hyperkalaemia makes the membrane potential less negative so it is closer to TP
Hypercalcaemia makes the TP less negative, decreases conduction velocity and shortens refractory period
Hypermagnesaemia increases PR interval

37
Q

2,3-DPG

A

Binds to beta chains of Hb
Formed in RBCs from a byproduct of glycolysis
Thyroid hormones, GH and androgens increase levels

38
Q

Aortic valve opening

A

Occurs when ventricular pressure > aortic pressure, 80mmHg

39
Q

Left ventricle

A

Is 3x thicker than RV

Has papillary muscles on the MV but not aortic valve

40
Q

Veins and venules

A

Capacitance vessels
Hold 2/3 of the circulating volume
Venules have a diameter of 0.01-0.2mm
Veins have diameter of 0.2-5mm
Easily distensible walls so very compliant between 0 and 10mmHg
blood entering venules has pressure of 12-20mmHg
Blood entering veins has pressure of 10mmHg

41
Q

Bohr Equation

A

VD/VT = PaCO2 - PECO2/PaCO2

42
Q

Lung metabolises

A 
Bradykinin
Noradrenaline
Serotonin 
PGE2 and F2a
Leukotrienes 
ATI —> ATII
43
Q

Blood flow to different organs

A

Coronary blood flow = 5% CO, 250ml/min
Renal blood flow = 25% CO, 1.2L/min, 500ml/min/100g
Cerebral blood flow = 15% CO, 700ml/min, 50ml/min/100g (majority to grey matter)
Hepatic blood flow = 25% CO (75% from HPV, 25% from hepatic artery)

44
Q

Muscle spindles

A

Sense muscle length so respond to stretching/contraction of muscles
When they are stretched, they fire via type Ia or II fibres to efferent gamma-motor neurones
These can be altered by descending pathways in the spinal tract
Involved in polysynaptic withdrawal reflex

45
Q

Swallowing

A

Involuntary process
Triggered by bolus of food moving into back of the mouth and sensed by swallowing receptors
The most sensitive are the tonsillar pillars
Soft palate is pulled up
Larynx is pulled up and anterior by the neck muscles
Epiglottis covers the opening of the larynx
Palatopharyngeal folds are pulled medially to prevent larger food pieces from passing
Upper oesophageal sphincter relaxes
Whole process takes 1-2seconds

46
Q

Cholecystokinin

A

Peptide hormone
Produced in the duodenal mucosa by enteroendocrine cells
Production triggered by fats and proteins
Slows GI transit time to increase digestion of fats
Causes release of digestive enzymes from pancreas and bile from gallbladder
Reduces gastric acid secretion
Increases satiety

47
Q

Drugs excreted unchanged in the urine

A 
Aminoglycosides
Cephalosporins
Ephedrine 
Digoxin 
Lithium 
Milrinone/mannitol 
Neostigmine 
Oxytetracycline 
Pencilling
48
Q

Lipid metabolism

A

90% ingested lipids are triglycerides
10-30% are broken down in the stomach, the rest in duodenum and upper jejunum
Bile salts are solubilising agents for fats and aid absorption

49
Q

Cerebral metabolic rate

A

Increases by 8% for every 1’C increase in temperature

50
Q

Lactate

A

Produced from pyruvate in anaerobic metabolism
So 2 molecules produced from 1 glucose
Lactate level rises sharply at 50-80% of VO2 max - in untrained people, lactate level rises sooner
80% is converted back to glucose in the liver via the Cori cycle
Filtered by the kidneys and reabsorbed to a Tmax of 75mg/min

51
Q

Glucagon

A

Stimulated by: cortisol, infection, theophylline, PDE inhibitors
Inhibited by: alpha stimulation, insulin, glucose, ketones, phenytoin and somatostatin

52
Q

Ranitidine

A

Increases pH and decreases volume of gastric secretions
IV dose is 50mg
Not an enzyme inhibitor (unlike cimetidine)

53
Q

Barbiturates

A

Alkalosis increases duration of action because tautomerisation from keto to enol form occurs at higher pH and makes the drug more lipid soluble
Excreted more readily when the urine is alkalinised

54
Q

Thiopental

A 
2mins post IV dose - in vessel-rich tissues
4mins - in muscle 
7mins - in fatty tissue 
Slowly recirculates (half life 8.4hrs)
Can cause demyelination in porphyria
55
Q

Heavy bupivicaine

A

0.5% bupivicaine + 8% dextrose

Primary FRCA (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions