Misc 7 Flashcards
1
Q
What is the mechanism behind dilutional hyponatraemia e.g. in heart failure?
A
Activation of RAAS and also ADH release from posterior pituitary
Both lead to fluid retention but only one of these leads to Na retention so relative hyponatraemia (TBS actually high)
2
Q
3 ways in which patients lose heat intraoperatively?
A
Radiation - from skin (there is also vasolidation which worsens this)
Evaporation - body surfaces and open cavities
Conduction into air and theatre table
Also cold fluids/anaesthetic agents, and shivering prevented due to paralysis
3
Q
Normal response to hypothermia?
A
Symp response - shivering, piloerection, periph vasoconstriction
4
Q
RFs for intra/post op hypothermia?
A
Pre op hypothermia
Worsening ASA grade
Major/exposed or prolonged surgery
Combined GA and regional
5
Q
What is the classic ECG finding in hypothermia and what is it? When is it seen?
A
J - Osborn wave
Usually seen at less than 32 degrees
Upward deflection between QRS and ST
6
Q
Complications of hypothermia in relation to surgery?
A
Coagulopathy
Decreased metabolism and CO
Decreased drug metabolism - prolonged mechanism of action
7
Q
Discuss division of total body water e.g. for 70kg male?
A
TBW = 42L 28L = intracellular 14L = extracellular 11.5L = interstitial 3.5L = intravascular
8
Q
Hartmanns composition?
A
Na 131 Cl 111 K 5 Ca 2 Bicarb (as lactate) 29
9
Q
0.9% NaCl composition?
A
154 Na
154 Cl
10
Q
What is the classification system for traumatic pelvic fractures? What are the 3 types?
A
Young and Burgess
AP compression - open book fracture
Lateral compression
Vertical shear - fall from height, superior displacement of one hemipelvis on the other
11
Q
What level do you apply a pelvic binder at?
A
Greater trochanters
12
Q
Discuss management of major bleeding due to pelvic fracture?
A
Any hypotenisve major trauma should have pelvic binder
Then discuss with IR if active bleeding and pelvic fracture
If no target - preperitnoeal packing
If large vessel injury not amenable to IR - vascular opinion
13
Q
Where do the majority of bleeds come from in pelvic fractures with blunt trauma?
A
Pelvic venous plexus
14
Q
Lethal triad of trauma?
A
Hypothermia, acidosis and coagulopathy
15
Q
What is the difference between Early Total Care and Damage Control Surgery?
A
DCS = haemorrhage control, compression of major cavities and decontamination ETC = early definitive treatment of injuries after period of initial resus
16
Q
Pathophysiology of Type 1 hypersensitivity reactions?
A
Antigens bind to IgE antibodies on mast cells and basophils/eosinophils
Then degranulate to produce histamine, heparin, platelet activating factor
Increase in leukotrienes, prostaglandins
Above cause vasodilation, smooth muscle spasm, capillary leak due to increased vascular permeability and excessive epithelial glandular secreteion
17
Q
Treatment of type 1 hyypersensisitvty reaction?
A
IM adrenaline 500 micrograms (0.5ml 1/1000) - can repeat after 5 mins if doesnt help
Chlorphenamine 10mg IV/IM
Hydrocortisone 200mg IV
IV fluid challenge 500ml
18
Q
How to size guedels and nasopharyngael airways?
A
Guedel = incisor to angle of mandible
NP airway = external nare to tragus
19
Q
What effect may jaundice have on pulse oximetry?
A
Bilirubin can falsely lower reading
20
Q
Complications of colloids?
A
Anaphylaxis
Coagulopathy
21
Q
3 causes of increased CVP?
A
Fluid overload/ventricular failure
Cardiac tamponade
Chronic respiratory disease
22
Q
Level 0 - 3 care?
A
0 = normal ward patient 1 = ward with critical care input 2 = HDU = single organ failure, 2:1 nursing 3 = ICU = multi organ failure, 1:1 nursing
23
Q
Caring for post op trache patient?
A
Humidified oxygen
Regular tube care and suction
Emergency kit availability
24
Q
Under what circumstance would you be fully immune to tetanus?
A
When you’ve had 5 doses - 3 in early months then 2 boosters
25
What causes tetanus?
Clostridium tetani
26
What is the neurotoxin produced by c tetani?
Tetanospasmin
27
Differences between exotoxin and endotoxin?
```
Exo= gram pos or neg, immunogenic
Endo = gram neg only, non-immunogenic
```
28
Alpha 1 activation causes?
Vasoconstriction and increased duration of contraction
29
Beta 1 activation causes?
Positive inotropy and chronotropy with minimal vasoconstriction
30
Beta 2 activation causes?
Vasodilation
31
Dopamine1/2 activation causes what?
Kidneys - induces diuresis
32
What is dobutamine most useful for and why?
Beta 1/2 activation to cause improved cardiac contractility and reduce afterload
33
Why is norad preferred in e.g. septic shock?
Acts primarily on alpha 1 to cause vasoconstriction with relatively little tachycardia
34
2 ways of calculating MAP?
(SBP + (2xDBP))/3
| (COxSVR) + CPP
35
What is CVP monitoring useful for?
Gives indication of volume status (cardiac filling)
36
What is preload?
Ventricular filing - how fmuch its stretched pre systole (end of diastole)
37
Why would you consider ET intubation for mechanical ventilation?
Airway reasons - low GCS, facial/upper airway trauma etc., obstruction from inhalation smoke etc
Breathing - respiratory failure due to lung pathology, due to neuromuscular failure or to manage head injuries
38
Just intubated somoene and they are still hypoxic? What do you do?
call for help, apply 100% O2
Check tube position, if in doubt take it out
Check tube blockage
Check for kinking/disconnection
Manually bag to assess compliance - ?bronchospasm
Rule out pneumothorax
Check ventilator working properly
39
Define ventilation?
Tidal volume x respiratory rate
40
3 basic types of mechanical ventilation?
Prsesure controlled
Volume controlled
Pressure suport - supports patients own work of breathing
41
Normal tidal vlume by weight?
7ml/kg
42
Immediate, early and late complications of mechanical ventilation?
Immediate - airway trauma, failure, dental damage
Early - baro/volume trauma - pneumothorax/pneumoed/emphysema, raised intrathoracic pressure and reduced preload leading to CV collapse
Late - VAP, respiratory muscle atrophy, tracheal stenosis, tracheal fistula
43
3 rerquirements for weaning ventilation?
Resolution of intiial reason for ventilation
Adequate gas exchange - reducing O2 req
Adquate resp drive and power - spontaneous breathing trials
44
Managing new AF (acute) that doesnt resolve with correction of cause?
If stable - oral cardioversion e.g. amiodarne, digoxin
| If unstable - DC or chemical cacrdiovert
45
Give 4 specific post op complications of open AAA repair?
Abdo copmartment syndrome
Bleeding
Lower limb ischaemia
Post op ileus
46
What postiion for remove central line? Why?
Head down or supine
| To reduce risk of air embolus
47
How might teunnelled lines need to be removed?
In theatre - larger incision needed to dissect to plastic retaining cuff
48
5 causes of ischaemia?
```
Obstruction of arterial supply
Obstruction of venous outflow e.g. compartment syndrome
Anaemia
CO poisoning
Pulmonary disease and poor oxygenation
```
49
Likelihood of reinfarction if major surgery within 1 month post MI? Vs over 6 months?
30%
| vs 5%
50
Clopidogrel lasts for how long?
8 days - lifespan of platelets
51
Mechanisms of actino of aspirin?
COX 1 (blocks thromboxane A2 formation, platelet aggregation) and COX 2 (analgesia ,antiinflammatory/pyriexa) inhibition
52
Mechanism of action of clopidogrel?
Prevents platelet aggregation oby irreversibly inhibitring plaetelet ADP receptor
53
What are the 2 phases of metabolic response to injury?
Ebb - decreased CO, metabolic rate, energy expenditure and temperature
Flow - catabolic then anabolic phase
54
Risks/beenfits of NJ tubes?
Good - thinner, less uncomfortable, less risk of aspiration
| Bad - more prone to kinking/blockign, may need radiological insertion
55
What kind of enteral feeding is preferred in pancreatitis and why?
NJ
| Because bypasses DJ flexure, reducing secretion of cholecystokinin (which worsens pancreatic inflammatory process)
56
How is respiratory quotient calculated?
CO2 excreted / O2 consumed
57
WWhat is usually in an epidural?
Local anaesthetic and opiate
| ee.g. bupivocaine and fentanyl
58
What are the 4 stages of pain sensation transmission? Which drugs act at each?
1 - transduction - e.g. NSAIDs
2 - transmission - LA
3 - modulation - TENS
4 - perception - opioids
59
Where are pancreatic pseudocysts usually found?
In leser sac, obstructing epiploi foraemn of winslow withi inflammatory adhesions
60
4 methods of drainage of pancreatci psueodcysts?
Percutaneous/IR
Endoscopic - via posterior wlal of stomach
Open pseudocystogastrostomy
Open psuedocystojejunostomy if inferior
61
Complicatinos of chronic pancreatitis?
```
Psueodcyst
Peripancreatic fluid collections
DM
Malnutrtition
Biliary obstruction
Fistula formation - pancreatic ascites
```
62
RFs for breast cancer?
```
Early menarche, late menopause
Increasing age
FH/genetics
Nulliparous or late 1st baby
Smoking
Obesity
Use of HRT
Prev breast Ca
```
63
What is BRCA 1 associated with?
Breast, ovarian and fallopian Ca
64
What is BRCA 2 associated with?
Breast, pancreatic Ca, melanoma
65
What is the breast sceening programme?
Mammogram ervery 3 years from 50 to 71 routinely
66
How is sentinel node biopsy performed?
Radio isotope/blue dye injected to subdermal layer around areola pre-op - at surgery sentinel lymph node identified with dye/geiger counter and excised, frozen section - if positive all LNs removed
67
What is DCIS?
Most common non invasive breast Ca, microcalcifications, histologically looks like abnormal cells within BM
68
What is the difference between simple and skin sparing mastectomy?
In simple, whole breast taken. In skin sparing, nipple-aerolar complex is preserved
69
What layer is dissected down to in WLE breast Ca? What is placed on this layer?
Down to pectoral fascia
| Titanium clips placed on fascia to facilitate accurate radiotherapy
70
What are the levels of axillarry LNs?
```
1 = inferolateral to pect minor
2 = posterior to pect minor
3 = superomedial to pect minor
```
71
Complications of masteectomy?
```
Primary haemorrhage or haematoma
Wound infection
Skin flap necrosis
Wound dehiscence
Numb scar
Cosmetically poor scar
Seroma formation
Long thoracic or thoracodorsal nerve damage
Tumour recurrence
```
72
What 2 parts of the breast are rebuilt post mastectomy?
Breast mound
| Nipple areolar complex
73
Options for rebuilding breast mound?
Implant alone
Implant and flap e.g. lat dorsi myocutaneous flap
Autologous flap alone
74
Options for rebuilding nipple areolar complex?
Nipple reconstruction - usually done 6 months after treatment finished
Tattooing for areolar reconstruction
75
What are 3 kinds of flaps for breast reconstructino?
TRAM
DIEP
SGAP/IGAP (super/inf gluteal artery perforators)
76
Role of radiotherpay in breast cancer?
Offered to everyone who has had WLE to reduce recurrence
| Recommended if tumour over 5cm, positive resection margins, 4 or more pathological nodes in axilla, node positive
77
Local complications of radiotherapy in breast cancer?
Skin erythema or permanent discolouration
Lymphoedema
Swelling of remaining breast tissue
78
Discuss oestrogen receptors in breast cancer?
ER = 70% of breast cancers
Pre-menopausal - block production with tamoxifen for 5 years
Post-menopausal - block peripheral conversion with letrozole/anastrazole
79
What is herceptin used for?
Monoclonal Ab Trastuzumab used for HER-2 positive cancers
80
Is ER positivity a good thing in breast Ca? What about HER-2?
ER is good
HER-2 is bad
with respect to recurrence
81
First differential to rule out in acute flank/loin pain?
Rupture AAA
82
Potential outcomes of a mid ureteric stone?
```
Resolution
Ongoing colic
Obstruction
Obstruction and infection
Haematuria
SCC (if longstanding)
```
83
3 sites of stone obstruction in kidney stones?
Pelvi-ureteric junction
Pelvic brim, where ilaics cross
Vesico-ureteric junction
84
Causes of renal stones?
```
MEtabolic states
Abnormal anatomy eg horseshoe
Infections e.g proteus
Gastric e.g. IBD
Dehydration
High BMI, diet
```
85
Why does proteus cause renal stones?
Proteus cleaves urea to alkalaize urine
| This reduces solubility of PO4, prompting formation of struvite (magnesium ammonium phosphate stone)
86
5 kinds of renal stones?
```
Calcium oxalate
Calcium pyrophosphate
Struvite
Cystine
Uric acid
```
87
Differences between smooth and skeletal muscle?
```
Smooth = circumferential, autonomic (voluntary) and lines walls of viscera
Smooth = calmodulin, skeletal = troponin (calcium binding protein)
```
88
How is micturition controlled neurologically?
Storage phase - SNS - L1-3 relaxes detrusor and contracts internal sphincter
Micturition - PNS - S2-4 contracts detrusor and relaxes internal sphincter
External sphincter is under somatic control
89
3 ways of defining AKI?
UO under .5ml/kg for 6 hours
Creat rise over 26 in 48 hours
Creat rise in over 1.5x baseline in 1 week
90
Give 6 indicitions for renal replacement therapy?
```
Refractory hyperkalaemia
Fluid overload
Severe acidosis
Complications of uraemia e.g. pericarditis
Acute poisonoing
CKD 5
```
91
Divisions of types of renal replacement therapy?
Intermittent - haemodialysis, peritoneal dialysis
| Continuous - haemofiltration, haemodiafiltration, renal transplant
92
What is dialysis disequilibrium syndrome?
Acute onset of neurological symptoms in patients undergoing dialysis, due to rapid change in serum osmolality causing cerebral oedema
93
What is a naevus?
Benign proliferation of normal constituent cells of skin
94
Give 4 kinds of naevi?
Melanocytic
Vascular e.g. strawberry, port wine
Epidermal - warty
Connective tissue - Shagreen patch in TS
95
Act governing tissue donation in UK?
Human tissue act 2004
96
Indication for renal transplant?
End stage renal disease regardless of cause
97
Contraindications for renal transplant?
Malignancy that is not curative or not been in remission for 5 years
Untreated HIV/AIDS
IHD with 5 year predicted death of 50% or more
Chronic or persistent infection
Unlikely to comply w medications, regular class A drug taker etc
98
Where are transplanted kidneys normally put? Where does tranpslanted ureter go?
RIF
| Anastamosed to kidney
99
Blood supply/venous drainage of transplanted kidneys?
External iliac arery and vein
100
What are the main stages of organ recovery e.g. kidney?
Warm ischaemic - from when donor circulation stops to when perfusion solution flowing
Cold ischaemic - from when perfusion solution flowing to when kidney transplanted into recipient (kidney is on ice for transplant and shold be tx within 24 hours)
101
What is perfusion solution and what is it used for?
Ice cold solution of solutes, pH buffers, adenosine, membrane stabilisers etc to keep kidney viable
102
How is immunosuppression achieved with regards to transplant surgery?
At time - pred and an anti-CD drug of some sort
Maintenance triple therapy - pred, calcineurin inhibitor (tacro/serolimus/ciclosporin) and purine synthesis inhibitor (azathioprine)
103
Complications of immunosuppression associated with transplant?
```
Nephro/hepatotoxicity/neurotoxicity
Leukopenia
Skin changes
HTN, fluid retention
Effects of steroids
Malignancy e.g. skin
Infections esp atypicals
```
104
What is acute transplant rejection, what are the subdivisions and why does it happen? Treatment?
Accellerated if within first week, acute if within 100 days
T cell mediated, diffuse infiltration/arteritis/tubulitis etc
Treat with steroids at high dose
105
Why does chronic transplant rejection occur?
Humeral system - graft fibrosis and atrophy
106
Features of renal transplant rejection?
Pain, swelling, redness at site
Temperatures
Decreasing urine output and worsening renal function
Fluid retentino
107
How is renal transplant rejection diagnosed?
Biopsy
108
Complications of renal transplant other than rejection/complications of immunosuppression?
Delayed primary function - may be due to long cold ischaemic time or re-perfusion injury
Vascular - anastamotic leak, thrombosis, stenosis, vessel kinking
Urological - urine leak, ureteric stricture
Lymphocele - may need drainage
109
What is primary donor dysfunction in e.g. renal transplant?
Failure of donor organ to function in absence of any other obvious cause
110
1 year graft survival of renal transplants? Better or worse than other kinds?
Over 90% This is better than the other kinds
111
Symptoms of BPH?
Filling - frequency, urgency, nocturia
Voiding - hesitancy, incomplete voiding, terminal dribbling, poor stream
Other - retention, freq UTIs, haematuria, bladder stones
112
Invstigating BPH?
```
Exam incl PR
IPSS - prostate symptom score
urine dip
PSA
TRUS (trans rectal US)
IVU - IV urography
voidingi charts
urodynamics
```
113
Management of BPH?
Conservative - bladder training, avoiding drinks before bed, exercise, patient support etc
Medical - alpha blockers/5a reductase inhibitors
Surgery - TURP, open prostatectomy, laser enucleation
114
RFs for prostate Ca?
Age, Afrocaribbean/African, Obesity, FHx, diet
115
Scoring/grading system for prostate Ca?
Gleason score
116
Management of prostate Ca?
Stratify into local, locally advanced and advanced with MDT
Options include serveillance, radio/brachyterhapy, hormonal therapy (gosurelin, flutamide), TURP, chemo or steroids, radical prostatectomy or high intensity focused US/cryotherapy
117
Complications of TURP?
```
Bleeding
Infection
TURP syndrome
Retention or incontinence
Retrograde ejaculation
Strictures
Erectile dysfunction
```
118
Where are the urethral sphincter muscles in relation to the prostate?
```
Internal = above gland, at bladder neck
External = below gland, in deep perineal pouch
```
119
What is the prostatic utricle?
Small blind ended pouch opening in centre of seminal colliculus - openings of ejaculatory ducts are either side of utricle
120
Causes of bilateral parotid swelling?
Infection - viral e.g. mumps, bacterial e.g. TB
Inflammation - sarcoid/sjogrens
Metabolic - cirrhosis, cushings, myxoedema, bulimia, diabetes, malnutrition, gout
Local - sialectasis
Drugs - thiouracil, isoprenaline, high oestrogen OCP
121
Causes of unilateral parotid swelling?
Any of bilateral plus:
Cancer - benign or malignant
Stones or external ductal compression
122
What is pseudoparitomegaly and what causes it?
Mimics parotid swelling
| Due to either masseter hypertrophy or periauricular lymphadenopathy
123
Are stones more common in submadibular, sublingual or parotid glands? Why?
Submandibular - because saliva here has higher mucous content and increased concentration of calcium/phosphate than saliva of the others
Also submandibular secretion is against gravity, causing stasis
124
How might parotid/submandibular stones differ?
Parotid often small and multiple, 50% within gland
| Most submandibular are larger, solitary and intraductal
125
Pathology of salivary gland calculus formation?
Saliva is rich in calcium and phosphate
| Slow flow predisposing
126
Are salivary stones usually radio opaque?
Yes - majority of submandibular, and most parotid ones
127
Discuss parotid cancers?
Most benign e.g. pleomorphic adenoma or Whartins tumour, small amount malignant e.g. mucoepidermoid carcinoma or adenoid cystic carcinoma
128
Complications of parotidectomy?
Immediate - CN7 palsy, greater auricular nerve damage (and earlobe numbness)
Early - haematoma, infection
Late - Freys gustatory sweating, salivary fistula
129
What is Freys syndrome and why does it happen?
Gustatory facial sweating in region of auriculotemporal nerve (V3 branch) in response to gustatory stimulus
Due to autonomic nerve rewiring - following injury to auriculotemporal nerve as it reattaches to sweat glands in skin via symp fibres (rather than salivary gland)
130
What does the auriclotemporal nerve come from and what does it normally do?
V3 branch
| Usually PNS to parotid secretion/salivation, and SNS to face for sweating/flushing
131
What are the innervations of the rotator cuff muscles?
Supra and infraspinatus - suprascapular nerve
Subscapularis - subscapular nerve (also teres major)
Teres minor - axilalry nerve
132
Outline how you would test all the myotomes?
```
C5 - shouulder abduction/elbow flexion
C6 - wrist extension/elbow flexion
C 7- elbow extension
c8 - finger flexion
T1 - finger abduction
L2- hip flexion
L3 - knee flexion
L4 - ankle dorsiflexion
L5 - EHL
S1 - ankle plantarflexion
```
