MCQ OnExamination Flashcards
(464 cards)
1
Q
The openings in an HME filter are about 0.2microm, given that viruses and bacteria can be smaller than that how do they filter them out?
A
Though a seive action the Brownian motion of particles means that they do not slip through
2
Q
Tell me about pyloric stenosis?
A
Usually week 3-5 of life, male 6:1. Characteristic projectile vomit with hypoCl, hypoK metab alkalosis.
Hungry and keen to feed
3
Q
Where is most thyroid hormone stored in the thyroid gland?
A
Thyroglobulin
4
Q
Post partum what happens to ABG, blood volume, CO, gastric emptying and WBC?
A
ABG normal within a few days
Blood volume normal after 6 weeks
CO both SV and HR take 6-8 weeks to normalise
Gastric emptying reduced for 48hrs post partum
WBC normalise over 4-6 weeks
5
Q
What are the characteristics of a drug that has low hepatic extraction ratio?
A
Drug clearance insensitive to changes in liver blood flow
Clearance very sensitive to protein binding, intrinsic metabolism and excretion
No first pass metabolism if given PO
6
Q
Is lung compliance high or low in neonates? and Children?
A
Neonates high because of soft chest wall but after 1 year the value is lower
7
Q
How does FEV1/FVC vary with age?
A
High as children, slowly decreases to old age
8
Q
How is the carotid body altered in neonatal period?
A
At birth the response to hypoxia is blunted but get their normal sensitivity over a matter of days or weeks
9
Q
How long after birth are HbF mostly superceded by HbA?
A
6 months
10
Q
Whats the effect of anticholinergics on the lower oesophgeal sphincter?
A
Decreases tone
11
Q
Why do you get postural hypotension in early pregnancy?
A
Progesterone causes reduced SVR
12
Q
What happens with angiotensin II in pregnacny?
A
Increases therefore increasing water and sodium retention
13
Q
What happens with iron levels in pregnancy?
A
Iron levels fall but transferrin and TIBC rise
14
Q
What is TXA a synthetic analgoue to?
A
Amino acid Lysine,
15
Q
How does TXA work?
A
it binds to plasminogen preventing plasmin formation and displaces plasminogen from thrombin
It may also have anti-inflammatory effects and improve plt fn
16
Q
By how much did CRASH 2 say mortality was improoved by TXA?
A
If given with 8 hours ARR 1.5%
17
Q
Is mycoplasma associated with pneumothorax?
A
No
18
Q
What are normal pressures in RA, RV, PA and pulm occlusion pressure?
A
RA 0-12
RV2-25
PA 12-25
Occ pressure 8-12
19
Q
What is A-mode and B-mode US?
A
A-mode is the single line in the scan, B-mode (what you see normally) is many many A-mode images
20
Q
How does increased pulmonary venous pressure affect lung compliance?
A
decreases compliance
21
Q
What is normal lung compliance?
A
About200ml/cmH2O (combined with chest wall complaince which is about 70-80ml/cmH2O)
22
Q
What is the most sensitive measure of mild COPD?
A
FEF 25-75% which is the forced exp flow between 25 and 75% of an FVC manoeuvre. It corresponds to the airflow in the bronchioles. Can be difficult to interpret if the FVC is way off from predicted
23
Q
Post extubation stridor is apparently a frequent complication of intubation !? occuring in 2-16%. What are the risk factors?
A
Female, intubated >36hrs, excessive cuff pressure, large tube size, tracheal infection
24
Q
When should a ACEi be stopped after it has been started acutely?
A
If cr increases by >20%
25
If someone in cardiac arrest is on a thiazide what electrolyte abnormality should be empirically corrected in refractory VF?
Mg
26
What drugs are affected by the acetylator status of the patient?
Fast 40%, slow 60% of pop
| Hydralazine, isoniazid, suphonamides, procainamide are all affected
27
What is the dose of adrenaline in cardiac arrest in children?
10microg/kg, use 1:10000 soln
28
What is the energy substrate used by the heart at rest?
50-70% is fatty acids, 30% glucose.
29
The superior pharyngeal nerve arises from which cranial nerve?
Vagus
30
How many branches does the superior laryngeal nerve have and what do they innervate?
small external- cricothyroid muscle
| large internal gives sensation to larynx above cords
31
A parameteric test requires normal distribution. what are their outputs?
P-value
32
Do parametric tests themselves measure give an analysis of variance?
No, ANOVA is required for rhat and is used to test multiple groups of parametric data
33
What is the pH aim in TCA overdose bicarb bolus?
pH>7.4
| If doesnt work can try glucagon, adrenaline and Mg
34
What is the best way to reverse thrombolysis-if that is something you need to do?
FFP and TXA
35
When should the thickness of a burn be examined?
Secondary survey
36
How are additional fluids calculated in a paediatric burn?
% burn xweight x4 same as adults
37
What is the definition of 1st dgree, 2,3 and 4th degree burn?
1st- supericialonly epidermis
2nd- partial thickness- epidermis and dermis
3rd- full thickness sub cut tissue inc hair follicles and sebaceous glands
4th complete- tendon, muscle, bone affected
38
In WPW is a wide or narrow complex expected?
Orthodromic and antidromic are possible, orthodromic in 70% and antidromic in the rest. Therefore narrow complex is to be expected
39
If someone with WPW comes with a narrow complex tachy how treat? And more advanced interventions?
Carotid sinus massage
NEVER adensoine if AF underlying as this can ppt VF
If shocked can DCCV with amiodarone
Avoid Verapamil
40
When is the best respiratory phase to see a pneumothorax?
End exp
41
Is FEF 25-75% under patient control?
No but the FVC is so where you define it starting and ending may affect your interpreation
42
Is eosinophilia useful in delineating between intrinsic and extrinsic asthma?
No, elevated commonly in both
43
The anterior pituitary produces what? Which subunits are similar and which different?
Produces glycoproteins with similar alpha subunits but unique beta subunits
44
Hormones of anterior pituitary?
LH, FSH, ACTH, GH, TSH
45
RIFLE classification- what is 'loss'
Loss is complete loss of renal fn for 4 weeks
46
What are some syndromes that make airway management difficult
Crouzon, cystic hygroma, Edward's, Goldenhar, Hurler's
47
What are the cardiovascular changes in HRS?
Increased CO, low BP, reduced SVR and renal vasoconstriction
48
What are the diagnostic criteria for HRS?
Cirrhosis, Cr >133, no improvment of Cr after 2/7 of albumin and stopping nephrotoxics, no shock, no proteinuria
49
What are the ECG changes in profound hypothermia T<28?
J waves prolonged PR, QRS and QTc, ectopics deteriorating into VT/VF
50
Give some L->R shunt conditions
ASD, VSD, PDA, coarc, AVSD and AS/PS
51
What are common cyanotic R->L shunt conditions?
ToF, transposition, anomalous PV drainage, tricuspid atresia, hypoplastic L heart
52
What are the four phases of a Valsalva?
1. Inc venous return from intra-thoracic vessels with associated dec HR and inc BP
2. High intra-thoracic pressure reduces venous reutrn, HR inc, BP dec tending to normal
3. release of pressure causes pooling of blood in lungs dec BP and HR remains high
4. reflex brady back to baseline as venous return stabilises
53
What is the classic blood picture of Addison's?
HypoNa, Hyper K (30% normal), metab acid withnormal AG, hypoglycaemia
54
What sort of RTA is Addison's?
type 4
55
Causes of adrenal insufficiency?
Autoimmune, withdrawal of steroids, TB, meningococcal haemorrhage into glad (Waterhouse-Friderichsen), HIV, Malignancy infiltration
56
What anaesthetic drugs are contra-indicated in porphyria?
Thiopentone and Etomidate
57
What are the advantages of goal directed fluid therapy?
Redues length of stay by 1.16 days, no different in criticl care, reduces renaland resp failure and post op wound infection
58
Can St John's Wort cause seretonin syndrome? What about Amitriptyline?
Yes and yes
59
Low plasma cholinesterase is associated with what?
Liver and renaldisease pregnancy, burns, hyper or hypothyroid
60
What sort of wave is used to calibrate the pressure transducer signal?
A square wave signal
61
What sort of frequency response should the transducer system have relative to the fundamental frequency?
10 times
62
What is the optimal damping factor for a pressure transducer cirtuit?
0.6-0.7
63
What is the ideal tubing to use in a pressure transducer?
stiff, less than 1.2m and of large diameter
64
How does T3 and T4 bind to thyroxine binding globulin and albumin?
Bind to both, very avidy to TBG but TBG only has a low capacity. Albumin has a larger store but T3/T4 less avidly binds.
65
How do brachial plexus injuries usually arise and how is it assocaited with clavicular fracure?
It is usually a traction injury but can occasionally be associated with a clavicle fracture
66
What nerve roots for Erb's palsy?
C5/6/sometimes 7
67
What does a T1 brachial plexus injury look like?
Klumpke's palsy weak flexors of wrist and fingers and intrinsic hand muscles. Loss sensation forearm. Can be associated with Horner's syndrome
68
What nerve root injury associated with winged scapula?
C567
69
TPN is suspended in soya bean oil. Whatis the ratio of nitrogen to potassium and magnesium?
1g nitrogen to 5-6mmo K and 1-2mmol Mg
70
What are the three zones of the adrenal cortex?
Zona glomerulsa, fasiculata, reicularis
71
What do each of the zones of the adrenal cortex produce?
Zona glomerulosa- outer most ->aldosterone
Fasciculata- glucocot-> cortisone, corticosterone, deoxycorticosterone (most physiologically active is cortisol)
Reticularis-> androgens-> DHEA and androstenedione
72
The adrenal medulla secretes mainly what?
Adrenaline with a little noradrenaline
73
What is the sympathetic innervation of the adrenal glands?
pregang symp nerve fibres from T5-11 mediated by cholinergic nicotinic transmission
74
What can a lupus mother cause in a neonate due to transmission of products through placenta?
Anti-Ro and La antibodies can cause neonatal lupus syndrome which usually cause arrhythmia most commonly complete block
75
What drugs to avoid in porphyria?
Definite:Barbiturates, phenytoin,
Possible: ketamine, atracurium, lignocaine, steroid
76
What are the advantages of HFNO?
Reduced anatomical dead spaceby increasing pharyngeal washout
Reduce work of breathing
Element of CPAP
Improvesmucociliary clearance
77
What are the changes in pregnancy that mean seizure frequency increases?
Compliance, altered pharmacokinetics and normal hormonal changes means seizures are more likely
78
What are the effects of anaesthetic drugs on SSEP and MEP in spinal surgery?
Sevo
79
What column does the SSEP travel in?
dorsal columns (ascending)
80
In inter-hospital transfers what do the guidelines say about hyperventilation, GCS drop and need for intubation?
If GCS<8 intubate. If GCS drops by 2 prior to transfer consider intubation. If M score drops by 2 then must intubate
Hyperventilation 4.5-5 if no raised ICP 4-4.5 if raised
81
Where is the classic mass of pyloric stenosis felt?
just to right of midline
82
At what level do the R phrenic nerve and IVC penetrate the diaphragm?
T8
83
Where does the azygoud vein and aorta penetrate the diaphragm?
T12
84
In ABO incompatibility what are the mechanisms of antibody-mediated reactions?
Intravascular and extravascular
85
What are the steps in intravascular ABO incompatibility reaction?
IgM, IgG, Anti-A or B activate the complement cascade by the classical pathway resulting in free haemoglobin in the bloodstream
86
How does an extra-vascular ABO incompatibility come about?
Intact RBC are removed from circ by mononuclear phagocytes in liver and spleen. Any cell coated with igG or C3 is broken down resulting in bilirubin, urobilinogen etc Caused by IgG, anti-D and other rhesus ab
87
What does a non-immune haemolytic reaction look like in blood transfusion?
RBC are damaged before hitting the veins, result in asymptomatic haemoglobinuria nad haemoglobinaemia
88
What may happen to someone with C1 inhibitor deficiency in blood transfusion?
May get angio-oedema from standard plasma products
89
What is a normal urine output for a 7 year old in ml/kg/hr?
1
90
How does gabapentin work?
Alpha 2 delta Ca channel subunit acting on Ca channels and NMDA receptors to increase production of GABA
91
What are Moclobemide and Tranylcypromine?
MAOIs though the latter is the dirtier of the two
92
Risk of anaphylaxis per 100k administrations for chlorhex, sux, teic, co-amox?
Chlorhex- 0.78
Sux 11.1
Teic- 16.4
Co-amox 8.7
93
The bundle of His has three fascicles, R and ant L and post L. What does bifasicular block mean?
R and either ant or post L block
94
What axis deviation does L ant hemi-block cause?
L axis (post L block causes R axis)
95
What is Moxisylyte?
a alpha 1 blocker for Raynaud's
96
With regards CPX what is the anaerobic threshold that conveys poorer outcomes?
<11ml/kg/min
97
In a severly unwell patient, what can be said of RR and a lactate >1.5?
RR is very sensitive but not specific at all. Onviously if you're sick your RR will be up but if you run the same is true.
Lact >1.5 is associated with a higher mortality
98
What does diabetic autonomic neuropathy usually affect?
Parasymp system with particular vagal disturbance. Troubling nocturnal diarroea, postural hypotension (30mmHg), gastroparesis, painless urinary retention, lower pulse on standing and pupils sluggish
99
Where is ADH synthesised?
Supra-optic nucleus of hypothalamus as a precursor molecule which is taken to the posterior pituitary where it is released
100
What channel does ADH act on in kidney?
Aquaporin 2 (ADH also stimulated by nicotine!)
101
Features of life-threatening asthma
PEF <33%
SpO2 <92%
PaO2<8
silent chest, cyanosis, poor resp effort, reduced GCS
102
What is the role of calcitonin?
reduces Ca by inhibiting absorption in intestine and renal tubules and inhib osteoclastic action. It inhib PO4 reabsorption in renal tubules
103
Can low PO4 cause central pontine muelinolysis?
Yes
104
In ROTEM define
1. clotting time
2. clot formation time
3. alpha angle
Clotting time is time from baseline to 2mm amplitutde
formation time- time for amplitude to inc from 2->20mm
Alpha angle is tangent to waveform at 2mm amplitude
105
in ROTEM what is A5 and A10?
Amplitude at 5 and 10min
106
What is a normal urine fractional excretin of Na? What causes it to be high and low?
1% is normal. of zero use if on diuretics
Less that 1% can be pre-renal but also seen in hepatic and cardiac failure
More than 1% intrinsic renal injury but not always
107
What causes renal red-cell casts?
Diseases affecting glomerulus- IgA neh, lupus nephritis, Goodpastures, Granulomatosis with polyangiitis
108
What are the causes of renal white-cell casts?
interstitial cell kidney disease such as pyeloneph and parenchymal infection
109
When do you see eosinophils in urine?
AIN which is caused by allergic reaction usually to drugs
110
What is a respiratory quotient?
Te ratio of CO2 produced by the volume of O2 per unit time
111
What is a noraml resp quotient?
0.8
112
What is the RQ of fat, protein, ethyl alcohol, pure carbs?
```
Carb 1
Fat 0.7
Protein 0.9
Ethyl alc
0.67
```
113
From where does the azygous vein arise and end?
Left ascending lumbar vein draining posterior thorax and oesophagus joining directly onto SVC
114
What drugs potentiate non-depolarising muscle relaxants?
Inh anaesthetics, amionglycosides and tetracyclines, hyperMg
115
Drugs that can be removed by filter?
Aspirin, ethylene glycol,Li, methanol, procainamide, theophylline, vanc, carbamaz
116
When is FFP recommended in major haemorrahge? Dose?
If Fib<1g, PT/APTT >1.5x
| Dose 15-30ml/kg
117
Can you get fibrinogen concentrate?
No,its not licenced in the uk
118
If patient has Eisenmenger's will O2 help oxygenation?
The answer says yes because O2 is a pulmonary vasodilator and will reduce the R->L shunt
119
Can steroids cause a metabolic alkalosis?
Yes
120
How does adrenal insufficiency result in distributive shock?
There are fewer alpha 1 receptor expression on arterioles due to low cortisol resulting in vasodilatation
121
How is osmolality measured?
Depression of freezing point as this is directly correlated to the concentration of solutes
122
Above what level is amylase virtually diagnostic of pancreatitis?
1000
123
What are other causes of raised amylase apart from pancreatitis?
Ruptured panc cyst, perf peptic ulcer, cholecystisi, mesenteric infarction, mumps, pregnancy
124
Does octriotide reduce mortatliy in pancreatitis?
No
125
In cocaine overdose what would you use first line for agitation and hypertension? Second line? What is contraindicated?
First benzo then CCB like nifedipine
| BB contra because of unopposed alpha effects resulting in worse htn
126
How does unopposed alpha stimulation lead to hypertension?
Balance between alpha 1 (constrict) and beta 2 (dilate) is reached. If unselected BB reduces B1 but also B2 then alpha 1 wins out leading to worse vasoconstriction
127
Does midazolam work on GABA A or B?
A
128
What is the bioavailability of midazolam?
40%
129
When transferring a patient in an ambulance what should monitoring be?
Non-invasive cuff useless
Should be able to see and hear screen
Needed for level 1-3 patients
Should be mounted either at level of or below patient
130
How does SNP work? Problems withit?
Prodrug causing arterial and venous dilatation, reduce BP and reflex tachy
Problems- breaksdown in sunlight making it dark brown/blue (from straw colour), also tachyphylaxis
131
What are the voltage criteria for LVH?
S in V3 and R in aVL >24mm in men and 20 in women
R in I and S in III >25mm
Sin V1 + R in V5or6 >35mm
Mostly used S wave depth in V1 + tallest R wave height in V5-V6 > 35 mm
132
What does lead II look at on ECG?
Inferior (posterior) part of heart
133
What are the poor prognostic factors in OOHCA?
Sepsis, CVA, cancen, dementia, 2 or more chronic diseases, cardiac disease, CPR >5min
134
If patient makes it to hospital afer OOHCA what are the poor prognostic indicators?
Coma after CPR, hypotension, pneumonia or AKI, need for intubation, NYHA III or IV and older age
135
Symptoms and signs of seretonin syndrome?
Fever, confusion, clonus, hyperrelex, tremor, rigidity, hyperydrosis, shivering
136
Which breakdown product of codeine accumulated in renal impairment?
Morphine 6 glucuronide
137
When does sux cause hyperK?
Burns after 24 hrs, neuromusc disease inc tetanus, malig, hypovol shock, prolonged immobilisation
138
Why is adrenaline given in VF?
Preferential distribution of blood to coronary and ceebral circulation
139
What information is gathered during CPX?
12 lead with ST analysis, O2 consump and CO2 prod, MV, O2 sats, NIBP and subjective measure of exertion including Borg score (which is just that)
140
Which murmur would you expect in carcinoid syndrome and whats the underlying pathophys?
Tricuspid regurg (also PR) 50%have cardaic involvement usually R side with plaque-like thickening of valvular cusps being the issue
141
What dose of paracetamol allowed if 33-50kg, 10-33kg?
33-50 15mg/kg not exceeding 3g
| 10-33 15mg/kg not exceeding 2g
142
Class I antiarrhythmics all inhibit Na influx and slow phase 0 depolarisation are negaively inotropic and slow conduction velocity but what is the difference between Ia, b and c?
a- procainamide- increase refractory period
b- reduces refractory period
c - no effect on refractory period
all rely on K channel efflux regulation
143
In fat embolism what causes the rash? Can fat be seen in urine?
Can be seen in urine but who is looking?
| Rash is petechial directly secondary to fat emboli
144
acute intermittent porphyria- inheritance
Auto dom
145
What enzyme is missing in acute intermittent porphyria?
porphobilinogendeaminase means a build up of ALA and PBG which are increased in urine ( other conditions like variegate porphyria and coproporphohyria can also have these products present so the presence of elevated PBG ppts genetic testing)
146
Is ketamine safe in AIP?
Controversial but in high doses it has been implicated
147
What is the bioavailability of oral digoxin and how does it work?
70% available
direct and indirect actions
direct inhib Na/K ATPase rasising intracellular Na which increases intra cellular Ca->inotrope
Indirect- acetylcholine release prolong AV and budle of His refractory period
148
What ECG changes are seen with digoxin treatment (not toxicity)
longer PR, ST depression, T wave flat and short QT
149
Are steroids evidence based in thyroid storm
yes
150
Give examples of prodrugs and their active metabolites
Enalapril- enalaprilat
Diamorph- 6 monoatcylmorphine
codeine-morphine
parecoxib-> Valdecoxib
151
In CKD incidence of gout is unchanged. What happens ith 25-hydroxycholecalciferol?
25-hydroxycholecalciferol remains unchanged, vit D converts it to 1,25-hy...
RBC life is also reduced in CKD
152
What are the effects of hyperglycinaemia? (TURP absorption syndrome)
Fluid overload, acute hypoNa, cardiac toxicity (infarction), AKI (hyperoxaluria) and transient blindness (min-24r)
153
What is the advantage of thermodilution over indocyanine green dilution in PA catheter estimation of CO?
In thermodilution there's no recirculation peak
154
What are the equivalent doses to 5mg Pred in hydrocort, dex, methyl pred
Hydrocort 20mg
Dex 750microg
Methylpred 4
155
Which local anaesthetic is metabolised to O-Toluidine resulting in methaemoglobinaemia?
Prilocaine
156
How many Murphy eyes on an uncuffed RAE?
2, only one on cuffed
157
What characteristics means a drug can pass the BBB?
```
Molecular weight of drug <600 daltons
Degree of ionisation (non-polar)
Lipid solubility
Protein binding, and
Tertiary structure
```
158
What is the ALS protocol for arrest if T<30?
Give 3x shocks if shockable. If doesn't work warm them up.
| If 30-35C double length of time between drugs
159
What is ethylene oxide?
Industrial steralisation gas, used for plastics and sutures. Things like Iodine and Chlorhex only disinfectants
160
What is a platelet life span and what chemicals of note do they contain?
Adenosine di-phosphate and serotonin. 9-10days
161
Which organ has the biggest art->venous O2 extraction?
Heart- 80% at rest 90% during exercise
162
Half life od IV Mg
4 hours
163
How does Mg vasodilate?
Magnesium amplifies the release of prostacyclin by vascular endothelium
164
How does WHO say you should kill prions?
autoclave at 121°C for 30 minutes with 1N NaOH then autoclave them normally
165
Which BB have intrinsic sympathomimmetic properties?
Labetalol and Pindolol (along with others you've not heard of)
166
Water soluble BB don't enter the brain, which ones are they?
Atenolol, Sotolol and others you've never heard of
167
A positive congo-red stain is indicative of what disease?
Amyloidosis
168
What does a cholinergic crisis look like?
Hyperstimulated so diarrhoea, cramps, N+V secretions++, miosis, fasiculations
169
What does organophosphate poisoning look like?
Anticholinergic posion- so similar to a cholinergic crisis- hypersalivation, diarrhoea, miosis, etc
170
Can Carbimazole be used in pregnancy and in breast feeding?
Yes
171
With what is SIADH associated?
```
Drugs, (e.g. carbamazepine)
Selective serotonin reuptake inhibitors (SSRIs)
Head injury
Tumours
Pneumonia, and typically with
Oat cell lung cancer.
```
172
What happens to the RV in tetralogy of fallot?
hypertrophy
173
What happens to LV in PDA?
Hypertrophy
174
How long after thrombolysis is LP/epidural allowed?
10 days at least
175
What is the safes metal in MRI?
Chrome
176
What % of nec fasc is type 1 and type 2?
Type 1 80% polymicrobial
| Type 2 mono
177
What time frames do acute and chronic rejection occur?
Acute first 6/12 chronic thereafter
178
How is tissue rejection mediated in acute and chronic rejection?
Acute- T cell mediated
179
How does chronic rejection occur and present?
cell-mediated and antibody-mediated immune attack
| Fibrosis is the hallmark with slowly increasing Cr
180
What is a normal CO2 and bicarb at term in pregnancy?
CO2 32 (4.3), HCO3 21
181
Does vecuronium have active metabolites?
Yes, accumulate in renal failure
182
Intubating dose of Vecuronium?
0.1mg/kg (least histamine release of all relaxants)
183
What is qSOFA?
```
Low blood pressure (systolic equal or less than 100mmHg): 1 point
High respiratory rate (greater or equal to 22 breaths per minute): 1 point
Altered mentation (GCS<15): 1 point
```
184
What are the clotting changes in pregnancy?
Upregulation of all factors, plt normal, relative anaemia (50% inc in blood vol, 20-30% inc in RBC)
185
What happens to WBC in preg?
Slowly increase to about 9.5 at term
186
Does abdo radiotherapy cause pancreattis?
YEs but chronic rather that acute (is that right)?
187
Drugs associated with pancreatitis
Steroid, thiazide, GLP1, valproate, azathioprine
188
Amino amide LA
```
Lidocaine
Bupivacaine
Ropivacaine
Prilocaine
Levobupivacaine, and
Mepivacaine.
```
189
Amino ester LA
Chloroprocaine
Procaine
Tetracaine, and
Articaine.
190
Difference between amino esters and amino amide?
Amino amides metab in liver whilst esters metab by plasma cholinesterase
191
If VSD at birth what heart sounds do you hear and how is it corrected if cyanotic?
Splitting second heart sound. Most resolve spont but if pulmonary HTN and R->L shunt will need an operation but seldom do well
192
Can a ketostix be negative in DKA?
Yes because of reduced clearance
193
Is there evidence for PPI in variceal haemorrhage?
No
194
When do you start Terlipressin in a haemodynamially stable patient presenting with UGIB?
ASAP is nice recommnedation. Wouldnt in practice atm
195
What happens to lung compliance with age?
In elderly the lung compliance may not change much in health but the chest wall loses its compliance
196
How does dynamic compliance vary with frequency of ventilation?
inversely prop
197
Give some drugs tht have >50% pulmonary metabolism?
basic amines with pKa>8
| Fentayl is an example
198
What does STPD stand for?
Standard temp and pressure, dry
199
How do TCA exert their cardiac effect in overdose?
Slow phase 0 with their quinidine-like action resulting in slow conduction. Other mechanisms include abnormal repolarisation and impaired automaticity, cholinergic blockade and inhibition of neuronal catecholamine uptake
200
When would sodium bicarb be indicated in TCA overdose?
Tachy is ususal and is well tolerated. If QRS>100ms predicts higher chance of arrhythmia and so bicard should be given. It works by alikalinisation of serum which favours dissociation of tricyclic away from cardiac Na channels
201
Albumin half life?
30 days
202
Which is most common cranial or renal DI?
Cranial
203
What happens to DI in pregnancy?
Plaenta makes vasopressinase, this increases symptoms
204
Give examples of rare causes of bronchospasm
Aspergillosis (transient infiltrates, eosinophilia, cough and ashtma)
Carcinoid
Polyarteritis nodosa
205
What is the standard outer diameter of the end of an ETT>
15mm
206
What anaesthetic technique most reduces the stress response to surgery?
GA plus spinal above level of surgery. (said T4 on question so wonder if it always needs to be high)
207
What forms of thyoid hormone resistance are there? They are rare
Generalised and pituitary specific (GrTH and PrTH) They have high T4 and FT3 with normal or high TSH whilst being hypothyroid or hyperthyroid respectively
208
If someone stable on thyroixine for years and suddenly seen to need more it is usually because of another drug. What dugs increase thyroxine metabolism?
Rifampicin, st johns wort, carbamazepine, warfarin
209
What is the fourth heart sound?
High atrial activity in say LVH leading to dilated LA
210
What are the causes of a pathological third heart sound (may be normal <40)
MR/TR,dilated LV, AMI, low pitched (split S2 high)
211
What is the classical finding on auscultation in HTN?
Loud S2
212
What are the grades of hypertensive retinopathy?
G1- arterial narrowing
G2-AV nipping
G3- haem and exudates
G4- all above and papilloedema
213
What does prilocaine do to a pulse oximiter?
Makes it read low due to methaemoglobin
214
What is the gold standard for diagnosing renal artery stenosis, and best investigation?
Gold standard is angiogram but best Ix is MRI renal angiography, the USS RA has many false negatives
215
What would make you think of renal artery stenosis as a cause for HTN?
Refractory HTN to 3 agents >150/90
recurrent pulmonary oedema with normal LV
>20% rse Cr in 2/12 after starting ACEi
216
Which structure has the highest blood flow at rest (ml/min/100g)
```
Carotid body 2000
Brain 54
Heart 87
Tyroid 560
Kidney 420
```
217
What is the gold standard marker, using Fick's principle, for measuring GFR?
insulin clearance
| PAH is used in renal blood flow analysis
218
How much does anaerobic threshold fall between 60-80 years?
10-20%
219
Define anaerobic threshold
The point in exercise where products of anaetobic metabolism can no longer be eliminated
220
Below what anaerobic threshold does mortality increase with surgery?
11ml/kg/min
221
What type of RTA does spiro mimick?
Type 4
222
What is the clinical presentation of botulism?
Descending bilateral weakness with autonomic dysfn (dilated pupils with cranial neuropathies, normal sensation and no fever
223
How does botulism occur?
Clostridium botulinum produces endotoxins which prevent ACh release causing NMJ dysfunction and paralysis
224
normal urine output for neonate, infant, child and adolescent?
N-2-3ml/kg/hr
I- 2
child 1-2
ad 0.5
225
What sort of fast metabolisers are not allowed codeine? Why?
CYP2D6 rapidly metab to morphine putting them at risk
226
Can kids have codeine post op?
Avoid <12yrs and in breastfeeding as it passes via milk. Contra in any child after tonsillectomy for OSA
227
How does PTH exert its effects on osteoclastic and osteoblastic action?
Osteoblasts direclty, oesteoclasts indirectly via RANKL secreted by osteoblasts under control of PTH
228
Neonates compared to adults have what differences in airway and respiration?
Diaphragm main muscle, static compliance is lower
| Epiglottis is higher in neck, narrowest part of airway below flottis, main bronchi divide at equal angles
229
What is the largest contributor numerically to the net filtration pressure in the kidney which allows GFR
Afferent glomerular capillary hydrostatic pressure
230
on which side of the neck is the thoracic duct?
L side runs post to LIJ
231
In acute tubular necrosis what nitrogen/Cr ratio, specific gravity, urine osmo and urine Na would you expect?
NH3/Cr 10-20
spec grav <1.01
Urine os <350 and urine Na>40
232
What are key features of severe malaria?
Low GCS/seizure, renal impairemen (Cr>265), acidosis <7.3, ARDS, Hb<80, Spont bleeding, shock, haemaglobinuria, hypoglycaemia
233
Which common toxins can be filtered?
BLAST
| Barbiturates, Li, Alcohol, Salicylates, Theophyllines
234
MEN II which cancers?
Phaeo, Hyperparathyroid and medullary Ca thyroid
235
VWF deficiency, what does it do to PT and APTT?
PT is not invovled with platelets so normal
| APTT is so prolonged
236
What drugs stop labour?
Atosiban (oxy antagonist), terbutaline salbutamol, nifedipine, indomethacin
237
Why is GTN give S/L rather than PO?
High first pass metabolism
238
At what sort of level of aspirin do you think about RRT?
800mg/L
239
what is the effect on glycogen, gluconeogenesis and plasma glucose in catcholamine, corticosteroid and glucagon?
Catechol-glyc down, gluconeo up, glucose up
corticost- glyc up, gluconeo up, glucose up
glucagon - glycogen down, gluconeo up, gluc up
GH glycogen down, plasma glucose up
240
What do the presence of HBV e antigen?
If positive then highly infectious
241
What does HB surface ag mean?
its only seen in someone who has at some point seen the real virus. Ag being present could be acute or chronic
242
HBV surface antigen antibody means?
This is what the vaccine aims to make. It is also what someone who mounts a response makes. The issue with HBV is not everyone mounts a response
243
What does a HBV core ab mean>
Simply means you've had it at some point
244
IgM HBV core ab means what?
Acute infection, lasts for 6/12
245
What gives you a clue that a sickle cell pt has parvovirus as the driver for their anaemia and admission?
Low reticulocytes, in other causes like bleed, haemolytic crisis or splenic sequestration the retics would go up.
246
Afferent and efferent of gag reflex?
Glossopharyngeal aff
| Vagus eff
247
How does Mg help prevent seizure in eclampsia?
Dilates cerebral vessels and prevents vasospasm
248
What is the biochemical signature of Cushing's syndrome?
High urine free cortisol, 71% hypokalaemia and 72% high ACTH with peripheral oedema, personality change and skin pigmentation
249
What cancers can produce ectopic ACTH?
Bronchial carcinoid and small cell lung, pancreatic islet cell, medullary thyroid, thymic and met adeno
250
What happens to aldosterone in Cushing's syndrome?
Goes down
251
In ischaemic stroke when do you intervene with high BP?
?220/110
252
In nephrotic syndrome you become hypercoagulabel, why?
You lose antithrombin III from kidney (increased beta 2 microglobulin and reduced fibrinolysis
253
In ATN what would you expect the urine Na to be?
>30mmol/L
254
What does hypoglycaemia do to prolactin and ADH?
Elevate both
255
How does protamine work?
It binds and inactivates heparin
256
In glycolysis how many ATP molecules per molecule of glucose?
2
257
WHat does AF with CHB look like?
No P waves but regular rhythm. Important as it still needs a PPM and can be missed
258
How is Ca distriubuted in the plasma?
50% ionised, 40% bound (90% of which is on albumin), 10% are bound to anions
259
What neuro findings would you expect in hypoCa?
```
Dementia or overt psychosis
Irritability
Confusion
Hallucinations
Extrapyramidal manifestations (including hemiballismus), and
Seizures.
```
260
What cardiac changes would you expect in hypo Ca?
```
Bradycardia/tachycardia
Signs of heart failure
Prolongation of QT interval
Refractory hypotension, and
Arrhythmias
```
261
How long is a complete test in TEG/ROTEM?
60min
262
Is TEG/ROTEM good for plt function?
No, it doesn't take into account plt inhibition
263
GBS has a 10% mortality, if the cause is campylobacter is that better or orse?
Worse
264
If you MRI GBS whatould you likely see?
Gadolinium enhanced MRI scanning of the spinal cord may show selective anterior root enhancement
265
When is legionella serology useful>
Not in initial phase but if ongoing infection with urine screen negative can be useful after immune reaction has occured
266
What do you find in Conn's?
hypokalaemic alkalosis, low renin hypertension, muscle weakness because of alkalosis
267
What symptoms of SSRI OD?
tremor
drowsiness
nausea, and
vomiting.
268
Efferent in pupillary reflex?
Oculomotor III nerve fibres from the Edinger-Westphal nuclei
269
Which HLH is assciated with higher risk of SJS if given phenytoin?
HLA-B*1502)
270
Why consider vit D if long term pheytoin?
Can cause osteomalacia
271
Causes CSF protein of greater than 1.5 g/L
GBS, bacterial meninigits, TB
272
Does omeprazole inhibit cytochrome p450?
Yes
273
Oseltamivir 150 mg orally bd for 10 days is indicated for H1N1 but what do you give if absorption poor?
Zanamivir 300 mg IV for 10 days
274
When does pyloric stenosis ususualy presnt?
1 month of age
275
spinothalamic tract carries what?
Pain and temp terminating in thalamus
276
Posterior (dorsal) columns carry what?
Light touch and proprioception
277
What does methyl alcohol break down into?
Formic acid
278
What metabolic picture would you expect in methanol poisoning?
metab acid with low bicarb
279
Should digoxin be used in AV block?
No, it makes the block worse
280
Lambert -eaton is associatd with what cancer?
small cell lung
281
What sort of muscle weakness is classical of Lambert Eaton?
muscle weakness which improves with repetition and bulbar palsy
282
Whats the defib energy for paeds?
4J/Kg
283
Drugs that cause SIADH?
```
Selective serotonin reuptake inhibitors (SSRIs) (fluoxetine)
Tricyclic antidepressants
Sulphonylureas
Thiazides, and
Carbamazepine.
```
284
Where is SVR mostly modulated?
In small aterioles. In the pre-capillary artereoles autoregulation ocurs
285
Can phenytoin be used in digoxin toxicity?
Type IB anti-arrhythmics (e.g., phenytoin, lidocaine) can be used if digoxin immune Fab is unavailable or is being prepared and patients have rapid ventricular dysrhythmias unresponsive to supportive measures.
286
what is a gas critical temp?
A temp above which it is impossible to liquify with pressure alone
287
ACEi are teratogenic, what do they cause?
Oligohydramnios and skull deformity
288
How does digoxin work?
Slows conduction in AV node
289
Myasthenia Gravis is ab against ACh or Muscle specific kinase, the total ab count is unrelated to severity of symtpoms. What drug can ppt MG?
Pencillamine (chelating and RA drug)
290
In active cooling post cardiac arrest what temp fluids are 'ideal'
4C
291
Congential adrenal hyperplasia is due to 21-hydroxylase deficiency in 90%. What is the metabolic pattern and when does it present?
At birth, severe salt asting HypoNa, hypo glycaemia and hypotensionn (addisons)
292
What % is propofol protein bound?
98%
293
What receptors does propofol target?
GABA and glyceine
294
What factors increase O2 affinitiy for Hb (L shift dissociation curve)?
```
Hypothermia
Reduced PaCO2
Alkalosis
Reduced 2,3-DPG levels
Carbon monoxide
Methaemoglobinaemia and
Fetal haemoglobin
```
295
What factors decrease O2 affinity for Hb?
```
Elevated PaCO2
Acidosis
Hyperthermia
Elevated 2,3-DPG
Pregnancy
Haemoglobin S
Altitude
```
296
Typical plasma electrolytes in acute renal failure?
```
hyperkalaemia
hypocalcaemia
hypermagnesaemia
hyperphosphataemia
normal or reduced sodium concentration, and
high urea and creatinine concentrations.
```
297
To what is paracetamol conjugated?
Paracetamol is conjugated to glucuronic acid and sulphate under normal conditions
298
Side effects of organophosphate poisoning?
```
Salivation
Lacrimation
Urination
Defecation
(SLUD)
```
299
In child when should CT head be done within one hour?
Suspicion of non-accidental injury
Post-traumatic seizure but no history of epilepsy.
On initial Emergency department assessment, GCS less than 14, or for children under 1 year GCS (paediatric) less than 15.
At 2 hours after the injury, GCS less than 15.
Suspected open or depressed skull fracture or tense fontanelle.
Any sign of basal skull fracture (haemotympanum, 'panda' eyes, cerebrospinal fluid leakage from the ear or nose, Battle's sign).
Focal neurological deficit.
For children under 1 year, presence of bruise, swelling or laceration of more than 5 cm on the head.
300
What is the resting O2 demand for adult, pregnancy at term, sepsis, thyrotoxicosis, neonate at rest?
```
adult at rest 3.5ml/kg/min
Thyrotoxicosis 3.86
Neonate 7
Preg 5
Sepsis 4.5
Dobutaine infusion 4
```
301
What has the biggest impact on how long a LA block lasts?
```
Protein binding
(Bupivacaine 95%
Ropivacaine 94%
Levobupivacaine 97%
Lidocaine 75%
```
302
In what overdoses is repeated charcoal dose useful?
```
carbamazepine
aspirin
dapsone
paraquat
phenobarbitone
quinine, and
theophylline.
```
303
What K would you expect in threophylline OD?
HypoK
304
Why in an estabised T2DM can a glucose of 20 not give glucosuria?
There is adaptation to absorb more glucose above the 11mmol/l usual limit. It is thought to be due to more glucose transport molecules under insulin control.
305
Which cytochrome p450 is most likely to be subject to genetic variation?
CYP2D6
306
Whe would Digibind be considered?
```
Progressive bradyarrythmias not responsive to atropine
Ventricular tachycardia/fibrillation
Potassium greater than 5 mmol/L
Acute ingestion >10 mg in adults
Serum concentration >15 ng/mL.
```
307
Which hormones are secreted from the anterior pituitary?
TSH, LH, FSH, ACTH, GH, prolactin
308
Stroke in pregnancy is 1.5 per 100k, is bleed or ischaemia most likely?
ischaemia. RF migraine, pre-eclampsia and gestational DM
309
Are parametric more or less powerful (more likely to show a difference that actually exists) than non-parametric?
Parametric are more powerful, report p-values and should be normally distributed.
310
Thyroid is usually 30g, is Iodine internalised actively or passively?
Active
311
Acute intermittent porphyria present with what?
```
acute abdominal pain
peripheral and cranial nerve palsies
mental disturbances
seizures, and
coma.
```
312
What is the dose of intralipid for LA toxicity?
initial bolus of 20% lipid emulsion is 1.5 ml/kg followed by an infusion of 15 ml/kg/hour.
313
Normal dietary intake for Na, K, Ca, Mg, Cl, PO4 per day?
```
Sodium - 1-2 mmol/kg/day
Potassium - 0.7-1.0 mmol/kg/day
Calcium - 0.1 mmol/kg/day
Magnesium - 0.1 mmol/kg/day
Chloride - 1-2 mmol/kg/day
Phosphate - 0.4 mmol/kg/day.
```
314
Ephedrine can be used for other things apart from hypotension, given PO or IM, what conditions?
nocturnal enuresis and narcolepsy
315
Half life of mast cell tryptase?
2 hrs
316
hat cells of liver make plasma protein?
periportal
317
What cells of liver metabolise drugs mostly?
Centrilobular
318
10mg dex is the same as how much of pred?
70mg
319
What causes bronchoconstriction in asthmatics who react badl to NSAIDs?
Leukotrienes
320
Phenyleph is a direct acting sympathomimmetic why is it preferred over ephedrine in obstetrics?
Gives a better umbilical blood gas
321
What is the objective of renal autoregulation apart from maintaining flow beween MAP 80-160
Renal autoregulation minimises the impact of changes in arterial blood pressure on Na+ excretion.
322
What two mechanisms underlie renal autoregulation?
myogenic response and Tubuloglomerular feedback (afferent arteriole)
323
What will a gaviscon overdose do in children?
HyperNa
324
If you gave 1L 5% dex to someone, what would make them pee it out?
Inhibition of vasopressin
325
What is the best way of assessing pancreatitis severity?
Serial CTs, not serial Ca
326
Li potentiates NDMBs, how?
Inhibition of synthesis and release of ACh
327
Does MAC go up or down in preg?
Down, the progesterone levels are high which acts as a sedative
328
What is the dose adjustment for adeosine in theophylline co-administration?
Adeonsine dose should be increased as theophylline blocks its action
329
In mothers with hyperthyroid, can they take carbimazole whist breast feeding?
Yes
330
What is the most common cause of high T4 in preg?
Graves 1:500-2000 preg
331
What is the toxin that causes liver failure after ingestion of mushrooms? After how many days does it present?
After 3 days, liver and HRS. Amatoxin
332
Normal FRC is 3L M and 2.5L F. How does this alter under GA, moving from supine to standing, with age and in obesity?
Under GA loss of muscle tone decreases by about 500ml, standing increses by about 1L, aging increases FRC slightly and obesity it falls
333
How is WPW sub-divided and what's the difference?
Sort PR, elta wave and wide QRS but divided into type A+B
| Type A V1 +ve, Type B V1 -ve
334
Is adenosine a coronory dilator or constrictor?
Dilator
335
Which ECG leads are useful in diagnosing LVH?
Sokolov-Lyon criteria are rather cumbersome but leads V1,2,4,5,6 and I, III, aVL, aVF and aVR
336
After DCCV for AF how long should someone at high risk of stroke cont anticoag?
4 weeks (and pre-anticoag for 3-4/52)
337
What is the drug of choice for AF for <72hrs?
Flecanide
338
What are the causes of hypoNa with high urine Na (>20mmol/L)
Diuretic, Addison's, poor DM control
339
What are the two most significant factors in the Goldman cardiac risk index?
3rd HS and MI in last 6/12
340
What are the other 7 factors in the Goldman cardiac risk index?
age >70, AS, JVP up, non sinus rhythm, >5 ectopics/min (MI in last 6/12 and 3rd heart sound confer the worst outcome on their own)
341
What type of Ca channel do CCB work on?
L-type not N type
342
How are nimodipine and nifedipine related?
Nimodipine is a more lipid sol analogue of nifedipine
343
In quadraplegic patients what percentage gt autonomic dysreflexia?
85%
344
What are the aims early on in spinal cord injury?
avoid hypotension, mild hypocarbia, avoid high sugar and hyperthermia
345
What is the best buffer in whole blood and in plasma>
Haemoglobin accounts for 35% of whole blood's ability to buffer. If removed and only plasma then bicarb is most important, also 35%
346
In VSD what findings imply significant shunt?
HF, pulmonary plethora, mid dia murmur due to increased mitral valve flow
347
What cardiac abnormalities usually present with cyanosis?
ToF, TGA, hypoplastic L heart, tricuspid atresia, Eisenmenger'
348
What is thought to be the underlying mechanism in amniotic fluid embolism?
Foetal antigens start a cascade similar to anaphylaxis. Not simply and embolism
349
What are the phases of an amniotic fluid emolus?
Phase 1 - vasoactive mediators released in response to antigens in fluid. Causes massive pulm vasoconstriction causing hypotension and hypoxia
Phase 2 - LVF and pulm oedema, DIC, massive haem and uterine atony
350
When does amniotic fluid embolus occur?
80% in labour, 11% soon after. Can also be during evacuations and in second trimester
351
What makes up APACHE II?
GCS, Cr, hct, T, MAP, HR, RR, pH, oxygenation (A-a or PaO2), Na, K, WBC
Worst value of each in first 24 hrs
352
Where is water reabsorbed in kidney?
65-70% in prox conv tubule
| 20-25% in the descending limb which is freely permeable to water (thick ascending is impermeable to water)
353
Why are women more affected by alcohol?
Lower volume of distribution given fat composition
354
Define intrinsic activity
the capactiy of a drug-receptor interaction to produce maximal effect. Therefore antagonists have equal or greater affinity but zero intrinsic activity. Partial agonsits have similar affinity but partial intrinsic activity
355
Which antiemetics avoid in parkinson's?
Metoclop, haloperidol, droperidol, prochlorperazine
356
AAGBI recommendations for transport vent
Disconnection and high pressure alarms
The ability to supply positive end expiratory pressure
The ability to change the I:E ratio
The ability to alter the respiratory rate
The ability to change tidal volume, and
The ability to vary inspired oxygen concentration.
357
hat is normal HR, RR, SBP and U/O for children ages <1, 1-2, 2-5, 5-12 and >12?
```
<1 HR 110-160, RR 30-40, SBP 80-90, u/o 1-2
1-2 HR 100-150, 25-35, 85-95, 1-2
2-5 95-140, 25-30, 85-100, 1-2
5-12 80-120, 20-25, 90-110, >1
>12 60-100, 15-20, 100-120, >0.5
```
358
Dexmed is an alpha 2 agonist that has an 8 fold greater affinity cf clondine. What are its targets in the CNS and what effect do they have?
Lateral reticular nucleus and locus ceruleus reduce sympathetic output with sedation and anxiolysis. Dorsal horn of spinal cord modulate endogenous opiate
359
Use of gabapentinin acute pain is associated with what beneficial outcomes?
Reduced N+V, reduced opioid and other opioid s/e at expense of dizziness
360
Dose phenytoin in kids?
20mg/kg
361
Vasopressin is a nonapeptide similiar in structure to oxytocin. What vasopressin receptor stimulates the release of ACTH?
Via receptor V3 (antidiurectic effect V2)
362
Between Bup and morph which has the higher affinity for receptors?
Bup has 30x higherafinity but is obvious partial agonist
363
How much more potent is Fent vs morph?
100x
364
Morphine's bioavailablity PO?
30%
365
What class of evidence (I-IV) is RCT? Meta-analysis? Controlled study but not randomised?
Meta- Ia
RCT- Ib
Controlled but not randomised IIa
366
Define dromotropy and lusitropy
Dromotropy is ability to incease conduction velocity
| Lusitropy is acceleration of cardiac relaxation
367
How is levosimendan a novel inotrope?
It sensitises myocytes to intracellular Ca
368
How do people get NAC reactions?
Prev exposure means they are left with IgE ab
This would cause anaphylaxis.
Anaphylactoid reactions are common on first administration, slow rate of infusion if that happens
369
Dose of steroid in child for meningitis?
Dex 0.15mg/kg
370
Causes of hyperCa?
PTH, Malig (bone or PTHrp), sarcoid, myeloma, iatrogenic
371
During exercise uscle blood flow increases 20-50x, under what mechanism mostly?
Local autoreg
372
Why is dexmed only given IV?
has 100% first pass metab
373
Which abx for tetanus
Penicillin (or met if allergic)
374
What are the features of peptide (insulin, LF, FSH, GHRH)?
Lipophobic and interact on cell surfaces having auto and paracrine activity
375
What are benzo withdrawal symptoms?
Anx, insomnia, irritability, seziure and loss of appetite
376
Brown sequard distribution of deficit?
Contra pain temp
| Ipsi fine touch, proprio, vibration and motor tone
377
With what pelvic injury is urethral damage associated?
Anterior (ureter posterior)
378
For Vit D which reaction occurs in liver and which in kidney?
25 hydroxylation in iver, 1hydroxylationin kidney
379
What are the main stimulatns of 1 alpha hydroxylation (kidney) for Vit D?
Hypo PO4 and hypo Ca2+
380
Define 1 Gray
1J of ionising radiation per 1kg matter
381
What damage does x-ray or gamma ray of 2, 3,4,5 Gy cause?
2Gy cataracts
3Gy skin burn
4Gy sterility
5Gy hair loss
382
What is the most likely cause of A-a gradient in health?
low V/Q likely from atelectasis
383
What does methylene blue doto SpO2 readings?
absorbs at 670 so gives false low reading
384
Etomidate causes adrenal cortex suppression by what mechanism?
inhib 11 beta hydroxylase
385
If you inject oxytocin (syntocinon) what would the effects be?
Inc CO (SV) , transient fall in SVR with reflex tachy, skin flush, autotransfusion from uterine contraction, reduced uretoplacental blood flow and hold onto water with water intoxication if large dose
386
Which abx interfere with cell wall synthesis?
Penicilin, cephs and Vanc
387
Which abx interefere with cell membrane integrity?
Polymyxin B
388
Which abd prevent DNA synthesis?
Fluroquinolones (cipro, levo), metronidazole
389
Which abx interfere with folate synthesis?
Trimeth sulphonamides
390
Which abx interfere with protein synthesis
Aminoglycosides, tetracyclines, eryth, clinda, chlorampnehnicol
391
What forms of Sickle cell disease exist? What PaO2 do each sickle at?
HbAS and HbSS
Heterozyg HbAS 2.5-4kPa
Homo HbSS 5-6kPa
Other possible Hb have low sickling about 4kPa
392
What is the Sickledex test?
Reagent added to blood, if goes turbid know HbS present then genetic ttesting to check which one
393
Ho many spinal roots are there?
31 (c8, T12, L5,S5, coccygeal 1)
394
How many arteries go to spinal cord?
Two post, one ant that do not form anastomoses at each spinal level
395
Posterior arteries ensure what sesnation?
proprioception, vibratio and two-point discrimination
396
If someone ha gone crazy after hyoscine how do you treat them?
They could have central anticholinergic syndrome
| Treat with 15-60mcg/kg Physostigmine
397
Over what range is a pulse ox accurate?
70-100
398
What is the spont revertion to SR from AF?
60% over a few days (if given drugs 90% revert in first 7 days)
399
When should flecanide be avoided?
Structural or IHD
400
How does glucose get into cells?
There are 4 glucose transport proteins (GLUT) in cel walls.
GLUT1- universally
GLUT2- gut, liver, panc
GLUT3- CNS
GLUT4-skeletal muscle, adipose tissue, heart
401
Which GLUT is not insulin dependent?
GLUT3-CNS
402
Insulin makes K go into cells, which other electrolytes?
Mg an PO4
403
How is acute blood loss dealt with by the body in the first few minutes?
Venoconstriction is the first mechanism followed by liver peri-sinusoidal vasoconstriction reducing the 15% blood volume in liver and dumping it back into circulation
404
1 MET =?
3.5ml/kg/min
405
Over what time period does the ductus venosus, ductus arteriosus and foramen ovale close?
DV- 3-10days
DA- 36hrs
FO- immediately on birth due to reduced PVR
406
What is a reasonable anti-pseudomonal abx in CF?
Ceftazidime is an alternative to Taz
407
Common side effect of ketamine?
Salivation, lacrimation, nystag and pupil dilatation
408
Where is aldosterone synthesised?
Zona Glomerulosa
409
What does agiontensin II do to aldosterone?
Increaes secretion
410
Under optimal conditions is PPV or SVV better?
PPV but passive leg raise is even better
411
What did the relief study show?
2018, 3000 abdo surgical pts, restrictive (3.7L) vs liberal (6.1L) fluid for day 1 post op. No survival diff. AKI higher in restrictive group
412
Mortality of fat embolus? What % develop DIC?
5-15% mort, 50% develop DIC
413
What would Sarin poisoning look like?
Muscarinic and Nicotinic effects
Musc- paralysis, fasiculations, hypergly, ketosis
Nicotinic- Hypoten, Meiosis, GI disturbance
414
How many lumens does a PA catheter usually have? What is the balloon filled with?
3
| Air
415
What usually ppts an oculogyric crisis?
A typical neuroleptic like haloperidol or chlorpromazine
| Can happen but is unusual with new agenst like olanzapine
416
How do you treat an oculogyric reaction?
IV or IM procyclidine
417
Salicylate acide directly stim resp centre causing a resp alkalosis what happens then?
Excerete HCO3, K and H2O resulting in hypoK, dehydration and metab acidosis which is due to uncoupling of oxidative phosphorylation and increased fat metabolism. This occurs more quickly in kids
418
what happens to urine in aspirin OD?
Goes alkaline then becomes more acidic
419
What are the charaacteristics of type 2 fast twitch muscles?
Big, white (no blood), few mitochondira and ow myoglobin
420
Which components of the ABG are derived?
HCO3, BE, SpO2
421
Treatment for myxoedmea coma?
IV T3 and hydrocortisone
422
Where does pregabalin work?
Presynaptic calcium channels
423
What is the most frequent s/e of pregab?
visual disturbance NNH6
424
Pregabalin risk benefit means it isn't used after minor surgery. If used in after major surgery what are its benefits?
Less opioid
Slight decrease PONV
(gabapentin better tolerated but is more sedating)
425
Which common anaesthetic gas interferes with CO2 monitoring?
Nitrous
426
Normal ferretin?
>100mcg/l
427
What is Virchow's triad?
Local injury- vasculitis, prev throbosis
Inc coagulability- polycy, OCPD, cancer
Circ stasis- immobility, post op period, HF preg
428
Dose atropine in paeds?
Limited role in resus but if needed is 20mcg/kg
429
Half life ADH?
10-15min
430
Why is physostigmine used in central anticholinergic syndrome and not other anticholinergics?
Its the only one that crosses the BBB being a tertiary rather than quaternery amine
431
With regards resp control, to what do the medullary chemoreceptors respond directly?
CSF pH (though pH does not change rapidly due to the need for CO2 to diffuse)
432
The resp response to barorecptors detecting hypotension is what?
Resp stimulation
433
What artery is usually damaged in EDH?
Ant branch middle meningeal artery
434
What happens to ESR, albumin, WBC, plt and blood volume in pregnancy>
RBC and plasma volume inc by 50%
ESR (and CRP) inc in preg due to inc fibrinogen
Plt only fall by 5% (though there is increased turnover)
Alb production does not match plasma volume expansion so goes down by 25%, normal third trimester alb is 24-31
435
In type 1 VWF deficiency what blood product given in emergency?
Intermediate purity factor VIII (eg Humate-P)
436
How does LA protein binding affect duration of action?
The greater the binding, the greater the action
437
What does a high pKa mean for LA?
The higher the pKa the quicker the onset of action
438
Where is iron stored/used in the body?
Haem 65%, ferretin and haemosiderin 30%, myoglobin 3.5%
439
How do you calculate PVR?
PVR=(MPAP-PCWP/CO) x80
440
What is a normal pericardial fluid volume?
30-50ml
441
Who described the triad of hypotension, raised JVP and muffled heart sounds?
Beck
442
With nitrous, what happens to cerebral blood flow, PVR, myocardial contractility, GFR and SVR?
```
Cerebral flow- inc
PVR- inc
SVR- slight inc
contractility- slight dec
GFR- no effect
```
443
How is DM diagnosed with fasting and random glucose?
Fasting >7
| Random >11.1
444
What is your pO2 on summit of Mt Everest?
4kPa (atmos pressure 1/3 that at sea level)
445
How are drug clearance, vol dist and elimination constnat related?
CL=VdxK
446
How much energy is derived from 1g glucose and 1g fat?
1g gluc 4kcal
| 1g fat 9kcal
447
In severe aspirin toxicity haemofiltration or haemodialysis?
Haemodialysis. Nothing wrong with filtration it removed the drug more slowly is all
448
What is Lemiere's disease?
Rare, Fusobacterium necrophorum causs peritonsillar abscess with seeding of bacteria into jugular vein causing sepsis
449
How treat bradycardia in heart trasnplant?
Could use glucagon but Theophylline 100-200mg slow infusion is far better
450
What does theophylline do to the heart?
Positive chorno and dromotropy, inc SN and AV conduction likely through blockade of adenosine receptors
451
In kid with meningitis, how asssess if safe to do an LP with regards raised ICP?
Not CT as unreliable, use clinical assesssment
452
Where are mu receptors? and what do stimulating them caus?
brain, spinal cord, periaqueductal grey
| Causesanalgesia, meiosis, euphoria, brady, resp dep
453
What does kapa opioid receptor do?
analgesia, sedation, miosis
454
Delta opioiid receptor does?
analgesia and resp depression
455
What does hyperaldosteronism look like?
Alkalosis with uscle weakness or tentany if really bad, low renin levels, hypoK and hypertension
456
What is the rule for maintenance fluid in children?
```
Holliday-Segar 4-2-1 rule
1-10kg -4ml/hr
10-20kg 40ml+2ml/kg/hr over 10Kg
>20Kg 60ml +1ml/kg/hr above 20kg
Should be as close to normal osmo as possible. Children are very prone to hypoNa
```
457
Is coronary blood flow autoregulated?
yes
458
What do alpha glucosidase inhibitors do?
slow digestion of starch in small intestines
459
If PCP pt allergic to co-trimox what next?
Clinda and primaquine (+ pred)
460
What is charcot's triad?
Fever, RUQ pain and jaundice->cholangitis
461
What are the components of the bedside index for severity of acute pancreatitis? (BISAP)?
```
Urea >8.8
Impaired mental status
2 or more SIRS criteria
Age >60
Pleural effusion
ttaken within 24 hrs
```
462
What are Ranson's criteria for pancreatisi severity based on admission variables?
WBC >15
Age >55
Gluc >10
aised AST and LDH
463
Characteristis of acute adrenal insufficiency?
HypoNa, HyperK, raised urea, hypoCl, Hypuglycaemia, normochrom normocyt anaemia, neutropenia, high lymphocytes, hyperCa in 10-20%, metab acid due to low bicarb
464
What happens if you're on dobutamine for days?
Tolerance by downreg of B1 receptor
