MRCS May 1/52 Flashcards
1
Q
what compound can be used to identify parathyroid glands intraoperatively?
A
methylene blue
2
Q
what drug should be given preoperatively for removal of carcinoid tumour?
A
octreotide
3
Q
what drug should be given preoperatively for removal of phaeochromocytoma?
A
alpha and beta blockade
4
Q
what is dumping syndrome?
A
post gastrectomy
posprandial giddiness, abdo pain
caused by distension of JJM due to food contents with subsequent osmotic expansion and diarrhea, release of insulin causes hypoglycaemic symptoms
5
Q
describe the movement of ions in the myocardial action potential
A
rapid depol: rapid influx of sodium early repol: efflux of potassium plataeu phase: slow influx of calcium final repol: efflux of potassium restoration of ionic conc: slow influx of Na via Na/K ATPase
6
Q
definition of secondary haemorrhage in tonsillectomies?
A
5-10 days after
7
Q
what is it called when bleeding occurs in first 6-8 hrs after tonsillectomy? and what is mx option
A
reactionary/primary haemorrage - return to theatre
8
Q
describe Dieulafoy Lesions
A
AVM in gastric mucosa
9
Q
difference in presentation between anterior and posterior duodenal ulcer?
A
anterior: more likely to erode and cause peritonitis
posterior: might erode into gastroduodenal artery and present with UBGIT
10
Q
what arteries are more likely to be involved in gastric ulcers?
A
left gastric and splenic artery
11
Q
how can H pylori cause ulcers in duodenum
A
increased acidity of the stomach/ddm causes ddm to undergo metaplasia to gastric type epithelium which can then be colonised by H pylori
12
Q
what is the pathophysiology of h pylori gastric ulcers
A
h pylori produces urease which converts urea into ammonia, ammonia then stimulates production of gastrin which increases acidity of stomach, and causes chronic inflammation
13
Q
what are the effects of stimulation of receptors alpha 1, alpha 2, b1, b2, d1, d2
A
a1 and a2 cause vasoconstriction
b1 increases cardiac contractility and HR
b2 causes vasodilation (and bronchodilation)
d1 renal and spleen vasodilation
d2 inhibits release of norad
14
Q
which receptors does adrenaline target?
A
b1 and b2 and a1 and a2
15
Q
which receptors does noradrenaline target?
A
mainly a1, but also a2 b1 b2
16
Q
which receptors does dobutamine target?
A
mainly b1, some b2
17
Q
which receptors does dopamine target?
A
mainly d1 and d2 but also a1/a2 and b1
18
Q
description of mesenteric cysts?
A
smooth, mobile, non tender lumps, usually asymptomatic
19
Q
if pancreatic necrosis is suspected, what is the next step of action to determine management?
A
FNA for cultures to determine infection
20
Q
muscles in lateral compartment of leg
A
peroneus longus and peroneus brevis
21
Q
innervation of peroneous longus
A
superficial peroneal nerve
22
Q
characteristic of babies with choanal atresia?
A
cyanosis during feeds that improve when crying - switch to oropharyngeal airway breathing
23
Q
which muscles in the forearm originate from the common extensor tendon?
A
ECR-B
ED
ECU
EDM
24
Q
which muscles in forearm originate from common flexor trendon?
A
FCU PML FCR FDS pronator teres
25
rise in serum pH leads to rise or fall in serum calcium?
fall, ionised calcium will increase binding to albumin
26
how many % of ECF calcium is in free ionised state and how many % is bound to albumin?
40% free ionised
| 50% bound to albumin
27
work up for hyperparathyroidism
ECG
bloods: FBC RP chlor bicarb CMP iPTH, Vit D
24h urine calcium
imaging
28
drug causes of hypercalcaemia
thiazide diuretics, Vit D excess, antacid excess, lithium
29
biochemical picture of pri hyperparathyroidism
```
correct calcium - high
phosphate - low
PTH - high or abnormally normal (not surpressed)
chlor - mildly high
bicarb - low
pH - low
Alk phos - high
24hr urinary calcium - high
```
30
what is the half life of PTH
3-5 mins
31
indications for surgery in pri hyperparathyroidism
```
very high calcium
hyper calciuria
<30% crt clearance
1x life threatening hypercalcaemia episode
nephrolithiasis
age <50
osteoporosis
```
32
biochemical picture of secondary hyperPTH
high PTH
low or normal Calcium
high phosphate
low Vit D
33
what genetic syndrome assoc with parathyroid hyperplasia?
MEN1, sometimes MEN2
34
what to suspect if PTH >1000
parathyroid carcinoma
35
blood supply of parathyroid glands
inferior thyroid arteries
36
where are the superior parathyroid glands located usually?
1st tracheal ring
37
what incision normally used for parathyroidectomy?
traverse incision 2cm about sternal notch
38
complications to watch out for post parathyroidectomy?
haematoma and airway obstruction
hypoparathyroidism - hypocalcaemia
damage to RLN - stridor
39
what to do if postthyroidectomy patient starts to show signs of airway obstruction
inform senior KIV anaesthetist
prepare crash cart, oxygen mask
tracheostomy kit
KIV release neck sutures and relieve haematoma
40
what oral supplement to give post parathyroidectomy?
1alpha-calcidol
41
name of structure that drains submandibular gland?
whartons duct
42
which familial cancer syndrome is associated with extra teeth?
gardner's
43
which thyroid carcinoma characteristically shows more invasion and affects older women?
anaplastic carcinoma
44
What are 3 categories in the spectrum of breast cancer
1) hyperplasia with or without atypia
2) carcinoma in situ
3) invasive carcinoma
45
Describe breast hyperplasia w/ and w/o atypia and the increased risks of cancer
Simple ductal hyperplasia without atypia does not carry increase risk
But if atypia is found then up to 5x increase risk of breast ca, if severe atypia then up to 10x and and be mix with DCIS
46
5 classifications of breast cancer
1) histology type
2) TNM staging
3) cellular differentiation grading
4) HER/ER/PROG receptor status
5) pre or post menopausal
47
How is DCIS often picked up
May or may not be a/w palpable mass, often found on screening mammography
48
Describe the spread of DCIS
Not yet breached basement membrane, thus will show a branching pattern as it is confined within the ducts
49
What is comedo necrosis
Large cells with pleomorphic nuclei and luminal necrosis
50
Treatment options of DCIS and the considerations
Wide location excision with 2mm margins
KIV adjuvant RT after WLE if lesion is large or high grade
KIV mastectomy if DCIS is large/multifocal or central
KIV sentinel node biopsy if mastectomy done
KIV adjuvant tamoxifen
51
What is lobular carcinoma in situ
Not actually cancer, often incidental finding on histology but associated with increased risk of developing cancer
52
Described the increased risks of invasive cancer if LCIS is found with and without radiological changes
If a/w radiological changes then 30% of synchronous invasive cancer
If no radiological changes, 30% of developing breast ca in 15 years
53
Management options if LCIS is found
In young women: surveillance mammography
If high risk due to fmhx, KIV prophylactic surgery
In older women: might not need to do anything
54
what are the 5 subtypes of invasive ductal carcinoma
```
No specific type - 80%
Medullary
Mucoid
Papillary
Tubular ductal
```
55
Which type of invasive ductal carcinoma a/w feeling spongy
Medullary type
56
Which type of invasive ductal breast cancer has finger like projections, how is it treated as ?
Papillary, treated as DCIS
57
Which type of invasive breast carcinoma is more a/w bilateral breast cancer?
Invasive lobular carcinoma
58
What is the characteristic histological pattern seen in invasive lobular carcinoma
“Indian file” pattern, streaks of malignant cells
59
Invasive lobular carcinoma is often seen on mammography T or F?
F
60
What is inflammatory carcinoma, how is it treated
Breast cancer with local invasion a/w inflammation - poor prognosis, often aggressive. Treated with chemotherapy, mastectomy and axillary node clearance.
61
What is the risk of breast and ovarian cancer with BRCA1 and BRCA2 mutations
Breast: BRCA1 = 70% BRCA2 = 55%
Ovarian: BRCA1 = 30-60% BRCA2 = 10-30%
62
What is the recommended management for patients with high family history risk of breast ca and genetic mutation
Annual exam and mammography and consider prophylactic mastectomy with reconstruction
63
what is the link between hodgkin’s lymphoma patients and breast cancer, how should they be managed
Might have prev irradiation to the chest to treat HL, manage as per high genetic risk group with annual exam and mammography
64
What is taken into account in the nottingham prognostic index and what is the range of scores
NPI = 0.2 * size of tumor in cm + tumour grade (1 2 3) + lymph node involvement (1 2 3)
Ranges from 2.02 to over 6
65
How is regional staging done in breast cancer
Examination of axilla, US +/- US guided biopsy, if US negative then proceed with sentinel lymph node biopsy
66
Describe the process of sentinel lymph node biopsy
Radioactive compound e.g. technitium 99 colloid is injected into subareolar plexus preoperatively
Then followed by patent blue V dye.
During op, geiger meter is used to find radiactive nodes, guided by blue dye -> excise all sentinel nodes until no more radiactive or blue nodes
Send for histology either while pt is under GA or postop
If postive, patient to undergo axillary clearance
67
which clotting parameter will vit K def cause a derangement in?
APTT and PT - increased
68
what kind of ankle fractures can be treated conservatively? - what are the options?
stable fractures e.g. Weber's A (moon boot, WBAT)
| and some Weber's B (below knee cast, NWB x6/52)
69
what is osteopetrosis
dysfunction in osteoclast and bone resorption causing increased bone density
70
would acute tubular necrosis respond to fluids?
no
71
What is a bochdalek hernia?
Congenital diaphragmetic hernia with abdominal content inside thorax, may be a/w ipsilateral lung hypoplasia. Usually left posterior sided
72
What is a morgagni hernia
Hernia of the diaphragm at the foreman of margagni - anteriorly where sternum and diaphragm meet
73
What is a littres hernia?
Hernia of a meckel’s diverticulum
74
Where are chordae tendinae found?
Ventricles
75
What are chordae tendinae attached to
They hold the valve leaflets closed and attached to papillary muscle in the ventricle
76
Where are pectinae muscles found
Atrium, more in left
77
Contents of anterior mediastinum?
Thymus, fat, lymph nodes
78
Contents of middle mediastinum
Pericardium, heart
Aortic root
Arch of azygos vein
Main bronchi
79
Contents of posterior mediastinum
```
Oesophagus + vagus nerve
Thoracic aorta + thoracic duct
Azygos vein
Sympathetic nerve trunks
Splanchnic nerves
```
80
What is found at the mid inguinal ligament point?
Deep inguinal ring
81
Layers of scrotum from skin and what are they a continuation of from the anterior abdominal wall?
Skin -> dartos muscle (scarpa’s fascia) -> external spermatic fascia (ext oblique) -> cremasteric muscle and fascia (int oblique muscle and fascia) -> internal spermatic fascia (transversalis fascia) -> parietal tunica vaginalis (peritoneum) -> visceral tunica vaginalis (peritoneum)
82
Origin of anterior interosseous nerve and what it supplies
From median nerve
Supplies FPL, pronator quadratus, radial half of FDP
No cutaneous sensory innervation
83
Origin of posterior interosseous nerve and what it supplies
Radial nerve
Motor: ECRB, ED, EDM, ECU, supinator, EPB, EPL, EI
Sensory: no cutaneous sensory innervation
84
Where is calcitonin released from
Thyroid gland
85
what are acceptable margins for breast conserving surgery?
1mm for invasive disease, 2mm for DCIS
86
Common sites of distant mets for breast cancer?
Bone -> lung -> liver
87
Options for breast conserving surgery
WLE or oncoplastic resections
88
Margins necessary for breast conserving surgery
1mm for invasive cancer
| 2mm for DCIS
89
What should be done after breast conserving surgery
Adjuvant RT
90
Contraindications to breast conserving surgery
Large cancers >4cm or large tumour:tissue ratio
Multifocal
Central tumours
Male
Recurrence after previous conserving surgery
If not eligible for RT
91
Risks to counsel patient for breast conserving surgery
```
Recurrence
Need for reexision if margins not met
Unpredictable scarring
Change in breast shape
Poor cosmesis if >10% tissue removed
```
92
Describe simple and modified radical mastectomy
Simple mastectomy - removal of nipple and all breast tissue
| If also doing axillary clearance then = modified radical mastectomy
93
What is a radical mastectomy
Mastectomy that includes removal of pectoralis muscles and axillary nodes
94
Risks to counsel patient on for mastectomies
```
Anaesthesia and surgical risks
Haematoma, seroma
Frozen shoulder
Disease recurrence
PSY effects
```
95
Risks to counsel for axillary clearance
Lymphodema on ipsilateral arm
Nerve damage - numb inner arm, lats dorsi, serratus anterior, pectoral nerves
Shoulder stiffness
Haematoma, seroma
96
Difference between primary and adjuvant hormonal therapies, indications?
Primary hormonal therapy = no surgery. Indicated for patients where surgery is contraindicated, better outcomes if cancer strongly ER positive
Adjuvant = after surgery to reduce risk of recurrence/mets
97
4 methods of hormonal therapy in breast cancer
SERMs = e.g. tamoxifen
aromatase inhibitors e.g. letrozole
LHRH antagonist
Ovarian ablation
98
Describe indications of SERMs vs aromatase inhibitors in breast cancer
SERMs more indicated in pre-menopausal women
| AI is more for postmenopausal women unless giving with LHRH antagonist as well
99
Why is letrozole contraindicated in premenopausal women
Causes hyperstimulation of ovarian oestrogenesis due to gonadotrophin feedback
100
Side effects of tamoxifen
```
Hot flushes
Vaginal dryness
Increased VTE risk
Weight gain
Rare - endometrial cancer, cataract
```
101
What is the optimal duration of therapy for tamoxifen, what happens if beyond?
5 years - increase endometrial cancer risk if beyond that
102
Risk of aromatase inhibitor?
Osteoporosis
103
Indications for radiotherapy in breast cancer?
After breast conserving surgery (invasive or DCIS)
If large breast cancer (>4cm, ≥3 nodes involvement, grade 3 cancer, lymphovascular invasion)
Can do RT to axillary if decline surgical clearance
104
Risks to counsel for RT for breast cancer
```
Skin changes - erythema, thickening, cellulitis, edema, necrosis
Osteonecrosis of rib
Radiation damage to heart/lung
Lymphodema if on axillary
Distortion to breast due to thicken skin
```
105
When is chemotherapy considered in breast cancer
Younger, premenopausal
If ER negative
Poor prognosis
Lymph node positive
106
How to investigate for distant mets of breast cancer
Bone - CMP, alk phos, xrays, bone scan, MRI
Lung - xray, CT, cytology
Liver - LFTs, US, biopsy
Brain - imaging
107
what kind of ankle fractures can be treated conservatively? - what are the options?
stable fractures e.g. Weber's A (moon boot, WBAT)
| and some Weber's B (below knee cast, NWB x6/52)
108
what is osteopetrosis
dysfunction in osteoclast and bone resorption causing increased bone density
109
would acute tubular necrosis respond to fluids?
no
110
best option for large bowel obstruction due to ascending colon carcinoma?
right hemicolectomy with ileocolic anastamosis
111
what is the lymph drainage of the vocal cords?
nil - watershed area
112
what is the artery that supplies the posterior duodenal wall and its origin
gastroduodenal artery
113
what lies between the two origins of pronator teres?
median nerve
114
where does the radial and ulnar artery bifurcate?
brachial artery @ antebrachial fossa
