Doctors Academy - Physiology COPY Flashcards
(157 cards)
1
Q
What physiological responses to do you get post surgery?
A
Reduce water and produce glucose
2
Q
What proportion of salivary gland secretions is secreted from the submandibular and parotid glands
A
25% parotid
majority submandibular
3
Q
what is the mechanism of action of glucocorticoids
A
they bind to intracellular glucocorticoid receptors located on the nucleus
(made from cholesterol in the adrenal cortex)
4
Q
Which main group of receptors does adrenaline bind to
A
Adrenaline binds to Alpha 1, alpha 2, beta 1, beta 2 but has more of an action on Beta 1 & 2
5
Q
Which receptor does Nor adrenaline a selectively bind to?
A
Alpha 1
6
Q
Which receptor does dobutamine selectively bind to?
A
Beta 1
7
Q
Which receptor does dopamine selectively bind to?
A
D-1 and D-2
8
Q
what is the effect of receptors binding to Alpha 1
A
- vasoconstriction (leads to increase BP and increased contractility of the heart)
- Prostate contraction
- bladder relaxation
- pupil dilation (constriction of radial muscles)
9
Q
what is the effect of receptors binding to Beta 1
A
- Heart - This is a positive ionotrope for the heard - increased cardiac contractility and Heart Rate
- Kidneys - Increased angiotensin and Increased renin secretion which lead to increased BP
Summary: Increased HR, heart contractility and BP
10
Q
what is the effect of receptors binding to beta 2
A
- bronchodiltion
- decreased GI motility and tone.
- Also acts on the liver to activate gluconeogenisis
- relaxes uterine muscle wall
11
Q
what is the effect of receptors binding to D-1
A
renal and spleen vasodilation
12
Q
what is the effect of receptor binding to D2
A
inhibits release of nor adrenaline
13
Q
what is the equation to measure renal plasma flow
A
Renal plasma flow = PAH (Urine) x urine flow / PAH (Artery) - PAH (vein)
14
Q
which clotting factors does warfarin affect
A
2, 7, 9, 10 and protein C + S
15
Q
Which of the following is the equivalent of cardiac preload?
A
End diastolic Volume
16
Q
How is MAP calculated
A
MAP= Diastolic pressure+ 1/3(Systolic pressure- Diastolic pressure)
17
Q
How is Cerebral Perfusion Pressure calculated
A
CPP = MAP - ICP
18
Q
What does TXA inhibit
A
Plasmin
19
Q
what is the antidote to midazolam toxicity
A
flumazenil
20
Q
what is the antidote to systemic effects of priolocaine?
A
Methylene Blue
21
Q
What laboratory test can be done to identity a fluid as CSF
A
Beta 2 transferrin assay
22
Q
what therapeutic agent is commonly used in the treatment of carcinoid syndrome
A
Octerotide
23
Q
What is the action of somatostatin and where is it released
A
released by the pancreas
- decreases pancreatic and gastric secretions
- inhibits growth hormone
- delays gastric emptying
24
Q
What is the action of gastrin
A
Stimulates gastric acid secretion and incrases gastric motility
25
What is the action of CCK and where is it released
Released from Duodenum (I cells in upper small intestine)
increases pancreatic secretions
stimulates gall bladder contraction and bile release
decreases gastric emptying
26
What is the action of secretin and where is it released
released from S cells in upper small intestine
* stimulates pancreatic secretions of water and bicarb
* decreasees gastric acid secreition
27
what is the action of VIP and where is it released
released in small intestine / pancreas
stimulates pancreatic secretions
decreases gastric acid secretion
28
What is the action of Alpha 2 agonists
relaxes smooth muscle tone of the GI tract and decreases motility
29
What are the 4 zones of the adrenal gland and what do they excrete
From outer to inner: GFRm ACD
1. Zona glomerulosa - aldosterone
2. Zona Foliculata - Glucocorticoid
3. Zona Reticularis - dehydroepiondosterone
4. Medula - Epinephrine + nor epinephrine
30
What clotting factors does Heparin affect
2 (Thrombin) & 10
31
What clotting factors does warfarin affect
2, 7, 9, 10
32
What clotting factors does DIC affect
1, 2, 5, 8, 11
33
What clotting factors does Liver disease affect
1, 2, 5, 7, 9, 10, 11
34
JVP wave:
## Footnote
What do the a, c, x v and y waves correspond to on the JVP waveform?
A wave - atrial contraction
C wave.- closure of tricuspid
X wave - atrial relaxation
V wave - venous filling
Y wave - Tricuspid opening
35
JVP Waveform:
What do absent A waves mean?
They are a sign of atrial fibrilation
36
JVP Waveform:
what do large a waves mean?
* Right ventricular Hypertrophy
* Tricuspid Stenosis
37
JVP Waveform:
what do cannon "a" waves represent
these are seen in complete heard block
38
JVP Waveform
what does a slow "y" descent mean
* Tricuspid stenosis
* Right atrial myxoma
39
JVP Waveform
What does a steep "y" descent mean?
* Right ventricular failure
* Constrictive pericarditi
* Tricuspid regurgitation
40
In what organ are Oxyphil cells found?
Parthyroid gland
41
in what organs are chief cells found
The stomach and the parathyroid glands (here they produce PTH)
42
In what organ are principl cells found
Kidneys (in the collecting duct of the nephron)
43
In what organ are chromaffin cells found
adrenal medulla
44
where are parafolicular c cells found
in the tyroid
45
for what pathology is a metaiodobenzylguanidine scan used?
this is specifically used for identifying phaeochromocytomas. in general it is the investigation of choice for neuroendocrine cells
46
In what condition are Auer Rods found
Leukema (AML)
47
In what condition are Hurthle cells found ?
Hashimotos Thyroiditis
48
In what condiion are Orphan Annie Nuclei found
Papillary Thryoid cancer
49
In what conidion are asteroid bodies found
Sarcoidosis
50
In what organ are hassels corpuscles found
Thymus gland
51
In what part of lymphocytes are B cels and T cells made
B cells are made in the cortex and T cells are made in the paracortex
52
What drugs do you need to stop prior to surger and when do you need to stop them?
1. Stop all anticoagulation prior to surgery
1. Warfarin 5 days pre op
2. Clopidogril 5-7 days pre op
2. On the day of surgery stop:
1. ACE inhibitors
2. Diruetics
3. Change steroids to IV Hydrocortisone
4. NSAIDS
l
53
what type of drugs can you continue for surgery?
1. Asthma medication
2. Parkinsons medication
3. antiepileptic medication
4. cardiac mediation
5. thryoid medication
6. cancer medication
7. immunosurpressents
8. all analgesia except NSAIDS
54
Genetics
What is the inheritance pattern of Cystic Fibrosis and Sickle Cell disease?
Autosmoal resessive
55
Genetics
What is the inheritance pattern of haemophilla
x linked rescessive
56
if a joint aspiration shows positively birefringent rhomboid crystals under polarized light microscopy what is the diagnosis?
Pseudogout (calcium pyrophosphate crystals)
57
if a joint aspiration sample shows negitively birefringent needle shaped crystals on light microscopy what is the diagnosis
gout (sodium urate crystals)
58
What are the causes of gynocomastia
* Testicular tymour
* Hyperthryoidism
* liver cirrhosis
* acromegaly
* Kallman's, Klinefelter's syndrome
* ectopic tumour secretion
* haemodialysis
Drug causes: (DISCKO)
D - digoxin
I - isoniazid
S - spirolactone
K - ketoconizole
O - oestrogen
59
what is the best measure of left ventiruclar contracility
Ejection fraction (if \<30% be concenered)
60
What are the features of MEN type 1
Three P's
1. Parathyroid pathology : Parathyroid adenomas
2. Pituitary pathology - prolantinoma / ACTH / Growth hormone
3. Pancreas pathology - pancreatic tumour
61
what is the most common presentation of MEN type 1
hypercalcameia
62
what are the classic featres of MEN type 11a
* Phaeocrhomocytoma (high BP)
* Medullary Thryoid cancer (Hypercalcaemia)
* Hyperparathyroidism
63
what are the classic features of MEN 11b
Same as MEN 11a + mucosal neuromas
* Phaemochromocytoma
* Medullary thyroid cancer
* hyperparathyroidism
* Mucosal neuromas
64
what are the classic features found on a post splenectomy blood film?
* Howell jolly bodies
* heinz bodies
* Poikilocytes (target cells)
* pappenheimer bodies
* Erythrocyte containing siderotic granules
65
What physiological changes do you get in responce to Cardiogenic shock? i.e. what happens to Systemic vascular resistance, HR, cardiac output etc
increased SVR (vasoconstriction in response to low BP)
increased HR (sympathetic response)
Increased Pulmonary Pressures
decreased cardiac output
decreased blood pressure
66
What physiological changes do you get in responce to hypovolemic shock?
blood volume depletion
increased SVR
increased HR
decreased cardiac output
decreased blood pressure
67
What physiological changes do you get in responce to septic shock? i.e. what happens to Systemic vascular resistance, HR, cardiac output etc
reduced SVR
increased HR
normal/increased cardiac output
decreased blood pressure
68
69
What part of the adrenal glands do phaeochormocytomas affect?
THe medulla of the adrenal gland
70
What are the symptoms of an acute haemolytic transfusion reaction and how would you diagnose this?
Symptoms include: Fever, Loin pain tachycardia and low BP.
Diagnosis: Direct Coombes test
71
What is the most common cause of hypercalcaemia in inpatients
Most Common - Malignancy
Second most common - primary hyperparathyroidism
72
Which receptor do Clonadine and Methyldopa selectively bind to?
Alpha 2
73
Which receptor does Salbutamol selectively bind to?
Beta 2
74
What is the effect of subtances binding to Alpha 2 receptors?
Relaxes smooth muscle tone of GI tract and decreased motility
75
What diuretics act on the:
* Proximal convuluting tubule
* Ascending Limb
* Proximal Distal Convoluting tubule
* Distal Convuliting Tubule
* Collecting Duct
* PCT: Manitol and Dopamine
* Ascending Limb: Furosomide
* Proximal DCT: Thiazides
* Distal DCT: Spironolactone
* Collecting Duct: Vasopressin antagonists
76
What substances are reabdorbed in the:
* Proximal convuluting tubule
* Ascending Limb
* Proximal Distal Convoluting tubule
* Distal Convuliting Tubule
* Collecting Duct
Proximal Convoluting Tubule:
* Antibiotics
* Glucose
* Bicarb
* Amino acids
Descending Limb: Water
Ascending Limb: Sodium Chloride
Proximal DCT: Calcium
Distal DCT: sodium + potassium
77
What would move the o2 dissociation curve to the left and to the right?
78
what is the mode of action of bisphosphinates?
decreases osteoclast activity by inhibiting osteoclast progenitor development and promotign osteolast appoptosis
79
What type of hypersensitivity reaction is Asthma / Hay fever and what is the cell mediator responsible?
Type 1 reaction - IgE responsible
80
What type of hypersensitivity reaction is autoimmune haemolytic anemia and what is the cell mediator responsible?
Type 2 - IgG and IgM mediated
81
What type of hypersensitivity reaction is SLE and what is the cell mediator responsible?
Type 3 - IgG, IgA and IgM mediated
82
What type of hypersensitivity reaction is Graft vs host disease and what is the cell mediator responsible?
Type 4 - T cell mediated
83
what are the 3 phases of gastric acid secretion and which produces the most acid?
1. Cephalic phase (smell / taste of food) - 30% acid production
2. Gastric Phase (Distension of the stomach) - 60% acid production
3. Intestinal Phase (food in duodenum) - 10% acid production
84
What are the hormonal changes in cushings disease and what are the common features?
Increased Cortisol and Incrased ACTH
* weight gain
* increased gluconeogenisis
* bitemporal vision loss
85
What are the hormonal changes that occur in addisons disease and what are the common features
Low aldosterone and Low cortisol --\> Low Sodium and high potassium
* Fatigue
* weight loss
* pigmentation
86
What are the hormone changes in Conns syndrome and what are the common features?
High aldosterone
* high sodium --\> water retention
* HTN
* Low potassium --\> muscle weakness and cramps
87
What do you give to a patient with Von Willebrands Disease pre operatively?
Desmopressin
88
Where is the majority of iron found in the body?
haemoglobin
89
what is the normal value for ICP ?
10-12mmHg
90
what is the normal value for Cerebral perfusion pressure?
70-90mmHg
91
What effect does CO2 have on the vessels of the brain
vasodilation
92
what ventilatory action should be taken in a patient with a head injury and high ICP ?
Controlled hyperventilation
93
94
What electrolyte disturbances cause torsades de pointes and what is the treament?
Hypokalemia and Hypomagnesemia
Treatment: IV Magnesium sulphate
95
which acute phase protein is most likely to increase in a patient with severe sepsis?
ferratin
96
what is the most important urinary acid base buffer
phosphate
97
How does PTH incraese serum calcium levels
it activtes vitamin D to increase absorbtion of calcium from the small intestine
98
what is the cause of pernicious anemia
Autoimmune antibodies to pariatal cells
99
what do pariatal cells secrete?
They secrte intrinsic factor and HCL
100
what can low intrinsic factor cause
low B12
101
What are the features of Type 1 and Type 2 respiritory disease
Type 1 = Low O2, Normal or low CO2
Type 2 = Low O2, High CO2
102
What type of lung disease is present with an FEV/FVC ratio of \<70%? and what are some expamples of causes?
Obstructive lung disease
E.g. COPD, Asthma, bronchiectasis, CF
103
What type of lung disease would be present if the FEV / FVC ratio was \>70% and what are some example causes?
Restrictive lung disease
E.g. fibrosis, sarcoidosis, CCF, Obesity
104
if the question gives a history of a male with multiple recent chest infections and no vas defferens what do they have?
Cystic fibrosis
105
in DIC what clotting factors are rapidly consumed?
Factor 5 and 8
106
which drugs lead to decreased renin secretion
betal blockers
NSAIDS
107
What is the substrate of renin
angiotensinogen
108
what is the typical value for GFR?
125ml / min
109
what percentage of sodium is reabsorbed within the nephron
90%
(65% in the PTC, 10% in DCT, 25% in loop of henle)
110
what is the equation for calculating GFR?
GFR = (Urine concentration x urine volume) / plasma concentration
111
what are the 4 phases of wound healing and what cells are predominantly present in each
1. Haemostasis (Seconds / minutes): Platlets
2. Inflammation (days): Neutrophils
3. regeneration (Weeks): Fibroblasts
4. remoddeling (years): myofibrobasts
112
# Define the following terms regarding lung capacity:
1. Tidal Volume
2. Inspiratory reserve volume
3. Expiratory reserve volume
4. REsidual volume
5. Functional residual capacity
6. Vital Capacity
7. Total lung capacity
8. Forced vital capactiy
1. **Tidal Volume** - volume of air inspired and expired during each ventilatory cycle at rest
2. **Inspiratory** **reserve** **volume** - maximum volume of air that can be forcibly inhailed following normal inspiration
3. **Expiratory** **reserve** **volume** - maximum volume of air focibly exhailed following normal expiration
4. **Residual** **volume** - volume of air remaining in the lungs after a maximal expiration
5. **Functional** **residual** **capacity** - volume of air remaining in the lungs at the end of a normal expiration
6. **Vital** **Capacity** - maximum volume of air forcibly exhailed after maximal inspiration
7. **Total** **lung** **capacity** - volume of air in the lungs at the end of maximal inspiration
8. **Forced** **vital** **capactiy -** volume of air that can be maximally forecfully exhailed
113
What does a FEV/FEC ratio of \<70% indicate and give examples of conditions that would cause this?
Obstructive respiratory cause
e.g. COPD, Asthma, Bronchiectasis, CF
114
What does a FEV/FEC ratio of \>70% indicate and give examples of conditions that would cause this?
Restrictive disease
e.g. fibrosis, sarcoidosis, CCF, obesity
115
What causes the first, second, third and fourth heart sounds?
First: AV valves shutting (heard best at the apex)
Second: Closure of aortic and pulmonary valves
Third: Rapid ventricular filling
Fourth: Ventricular distention due to stiff ventricles and foreful atrial contraction. This is a sign of ventricular hypertrophy or HF
116
how does arterial carbon dioxide levels affect cerebral blood flow?
high carbon dioxide levels increase cerebral blood flow
117
what are the causes of hypercalcaemia
Mnemonic for the causes of hypercalcaemia:
CHIMPANZEES
C alcium supplementation
H yperparathyroidism
I atrogentic (Drugs: Thiazides)
M ilk Alkali syndrome
P aget disease of the bone
A cromegaly and Addison's Disease
N eoplasia
Z olinger-Ellison Syndrome (MEN Type I)
E xcessive Vitamin D
E xcessive Vitamin A
S arcoidosis
118
what is the pathophysiology of graves disease?
IgG antibodies are formed against the TSH receptors on the thyroid gland
119
how does hyperventilation affect calcium levels and what symptoms does it cause?
Hyperventilation causes decreased calcium levels which leads to twitching and peri oral parasthesia
120
what are the causes of severe and moderate thrombocytopenia?
Causes of severe thrombocytopenia
* ITP
* DIC
* TTP
* haematological malignancy
Causes of moderate thrombocytopenia
* heparin induced thrombocytopenia (HIT)
* drug-induced (e.g. quinine, diuretics, sulphonamides, aspirin, thiazides)
* alcohol
* liver disease
* hypersplenism
* viral infection (EBV, HIV, hepatitis)
* pregnancy
* SLE/antiphospholipid syndrome
* vitamin B12 deficiency
121
what proportion of calcium filtered at the glomerulus will be reabsorbed by the renal tubles
95%
122
what factors increase gastric acid secretion
Vagal nerve stimulation
Gastrin release
Histamine release (indirectly following gastrin release) from enterchromaffin like cells
123
what are the causes of hyperkalaemia
* Acute renal failure
* Drugs:
* potassium sparing diuretics
* ACE inhibitors
* angiotensin 2 receptor blockers
* spironolactone
* ciclosporin
* heparin
* Metabolic acidosis
* Addison's
* Tissue necrosis/rhabdomyolysis: burns, trauma
* Massive blood transfusion
124
what substances stimulate insulin release
Glucose
Amino acid
Vagal cholinergic
Secretin/Gastrin/CCK
Fatty acids
Beta adrenergic drugs
125
what is the main componant of colloid in the thyroid gland
thyroglobulin
126
what is the bainbridge reflex
this is theincrease in heart rate mediated via the atrial stretch receptors that occurs following a rapid infusion of blood
127
at what level does the aorta bifurcate to give the common iliac arteries
L4
128
What is the treatment of colorectal liver metastasis?
Chemotherapy followed by surgical resection
129
What nerve innervates the SAN
No singular nerve innervates the SAN. It is innervated by a complex plexus of nerves
130
What do you seen on histology of amyloidosis?
apple green birefringence with polarised light
131
What is the treatment for malignant hyperthermia
Dantrolene
132
What is the mechanism of action of renin?
It hydrolysis angiotensinogen to angiotensin 1
133
From what cells is renin released?
Juxtomedullary cells of the kidney
134
What is the most common cause of hyper-chloraemic acidosis?
Iatrogenic causes - over resuscitation with normal saline
135
What drug is contraindicated in broad complex tachycardia
Verapamil
136
What factors increase and decrease gastric acid secretion
**Factors increasing production include:**
Vagal nerve stimulation
Gastrin release
Histamine release (indirectly following gastrin release) from enterchromaffin like cells
**Factors decreasing production include:**
Somatostatin (inhibits histamine release)
Cholecystokinin
Secretin
137
What electrolyte abnormality is most commonly seen in diarrhoea
Hypokalaemia
138
139
What are the causes of high anion gap acidosis
M - Methanol
U - Uraemia
D - DKA / Any ketoacidosis
P - Paraldehyde/phenformin
I - Iron / Isoniazid
L - Lactic acidosis
E - Ethylene glycol
S - Salicylates
140
What are the causes of a normal anion gap acidosis
Gastrointestinal bicarbonate loss: diarrhoea, ureterosigmoidostomy, fistula
Renal tubular acidosis
Drugs: e.g. acetazolamide
Ammonium chloride injection
Addison's disease
141
How does adrenaline affect renin secretion
It causes increased renin secretion
142
What are Desmoid tumours?
Desmoids are proliferations of myofibroblasts and tend to arise from aponeurotic structures Improve
143
what substance acts of the medulla of the adrenal gland to stimulate adrenaline release?
ACTH
144
what is the half life of insulin
\<30mins
145
what substance is used in the treatment of people with von willabrand factor who are bleeding
desmopressin
146
what is the treatment of hypercalcaemia
Calcitonin and IV bisphospinates
147
what substances do pariatal cells secrete
Hydrochloric acid
Calcium
Magnesium
Sodium
Intrinsic factor
148
what acid base disturbance does a PE cause
respiratory alkalosis
149
what is the treatment for a dystonic reaction?
procyclidine
150
Which part of the loop of Henley is impermeable to water?
The ascending limb
151
What condition is HPV 8 associated with?
Karposis sarcoma
152
What condition would you suspect with a raised V/Q
PE
a raised V/Q indicates there is a blocked blood vessel in the lungs
153
What is virchows triad?
1. Hypercoagulobility
2. Endothelial damage
3. Venous stasis
154
What factors decreases renin secretion
1. Beta blockers
2. NSAIDS
155
What is the most common inherited bleeding disorder?
Von willebrands disease
156
What substance is used to measure anatomical dead space
Nitrogen
157
What are psomomma bodies
These are clusters of calcifications
