MCQ Flashcards
What systolic target in trauma? What’s the exception?
80-90mmHg, in TBI have to balance needs
What did the PROPPR trial show?
pragmatic randomised optimal platelet and plasma ratios trial
showed a sig decrease in exsanguination for 1:1:1 vs 1:1:2 FFP:plt:RBC
BUT no mortality benefit at 1 and 3 days
Sig underpowered
In trauma when should cryo be used?
When fibrinogen <1.5-2g/dl
In trauma, if pelvic bleeding what would make surgical packing more appropriate than IR?
FAST positive
How does audio-guided USS work when putting in lines?
It does not make image just a doppler sound
What are the two complications more likely in landmark vs uss technique for line insertion?
PTX and arterial puncture
What are the commonest causes and absolute % for end-stage renal failure in UK?
DM (20-40%) HTN (5-25%) Glomerular inc IgA neph (10-20%) Idiopathic (5-20%) Intersitial disease (5-15%) Rare- Renal art stenosis, Polycystic kidneys, vaculitis combined represent <5%
What’s the definition of CKD?
A disruption of renal function or structure for >3months
What % of patients with CKD end up with end-stage CKD?
1%
What, in addition to eGFR, is a marker of prognosis in CKD? What are the cut offs?
Albuminuria
A1 <30, A2 30-300, A3 >300
What efficiency do HME filters work?
70%
Wha efficiency of humidification are cold and warm water baths in the circuit?
30% and 90%
What efficiency do ultrasonic nebulizers have in terms of generating circuit humidity?
100%
Why are ultrasonic humidifiers not commonly used in circuit humidification?
Can be too efficient and deposit water droplets into the alveoli, for that reason we use it for meds instead
What is gas in small bowel and rectum only suggestive of?
Large bowel obstruction
Gas and fluid levels in small bowel means what?
Can be normal or suggest ileus but not necessarily an obstruction
Can Thiopentone cause bronchospasm?
Yes and laryngospasm
Which muscle relaxant has the least histamine release associated with it?
Vecuronium
At what level does the coeliac trunk arise?
T12
What are the first branches of the coeliac trunk?
L gastric, common hepatic and splenic art
What does the coeliac trunk supply?
Greater curvature of stomach, liver, gallbladder, spleen, pancreas
Where does the portal vein collateralise with the systemic venous network?
Oesophgeal, rectal, paraumbilica and a few small connections with colic and retroperitoneal veins
How does the IMA drain?
In health via the superior rectal, sigmoidal and L colic veins into the inferior mesenteric vein which then joins the splenic vein
What is first line treatment for Aspergillosis?
Voriconazole. Posaconazole is a resue therapy
What is the classic CT sign of Aspergillus infection?
The Halo sign which is a nodule surrounded by ground glass
What are the classes of anti-fungals?
Cell membrane Triazoles- Fluconazole, Voriconazole etc Imidazoles- Ketoconazole Polyenes- Amphoterecin (liposomal preparations fewer side effects and have surpassed deoxycholate preparations) Allylamines- Terbinafine
Cell wall
Echinocandins- Caspo, Andiulafungin
Intracellular
Griseofulvin, Flucytosine
What are the site of action of antifungals?
Cell membrane (azoles), Cell wall (fungins), Intracelluar (Griseofulvin, Flucytosine)
If Voriconazole is contraindicated in Aspergilosis what is the next treatment choice?
Amphorecin B
What is the treatment of cryoptococcus meningitis?
2/52 Amphoterecin and Flucytosine followed by 8/52 fluconazole
Causes of pre-hepatic jaundice?
Haemolysis, haematoma absorption
Crigler-Najjar syndrome
Gilberts syndrome
Jaundice of newborn
Cause of hepatic jaundice
Cirrhosis, steatohepatitis, genetic-haemochromatosis, alpha 1, Wilsons,
From mets, autoimmune hepatitis, PBC, infection HAV HBV etc, liver abscess, heart failure and backpressure, toxins, HELLP
Drugs that cause hepato-toxicity
Hepatocellular- amidoarone, HAART, halothane, NSAIDs, PPI, rifamipicin, SSRI, paracetamol, TPN
Mixed- phenytoin, enalapril, amitriptyline
Cholestasis- steroids, TCA, erythromycin
What equation is used to calculate cardiac output from transpulmonay indicator dilution?
Stewart-Hamilton
How does oesophageal doppler measure cardiac output?
Measures descending aorta flow velocity and uses either measured or normogram data of aortic diameter to estimate volume. The proportion of cardiac output going to descending aorta is a large source of error
What is Fick’s principle?
blood to an organ can be calculated by dividing the amount of a substance taken up by the organ per unit time (A:V concentration difference).
Give a practical example of Fick’s principle in calculating cardiac output
The O2 update from lungs divided by the difference between mixed venous and arterial O2
What is the indirect Fick method
Uses CO2 instead of O2. The difference between arterial and venous CO2
What is the Penaz technique for cardiac output estimation>
A cuff with LED is put on finger. The cuff goes up and down to keep the light going through the finger and hitting the photosensor constant. The pressure changes correspond to the pressure waveform of arterial pulsation. From there through multiple assumptions CO can be calculated
What is first line treatments for non-high risk PE?
LMWH or Fondaparinux
When are LMWH and Fondaparinux not first line for non-high risk PE? What is the treatment?
If (ESC)creatinine clearance <30->UFH
(NICE) eGFR<30 then use UFH or dose adjusted LMWH with Xa levels
When can Rivaroxiban be used in PE?
Can be used as initial treatment in those with non-high risk PE by both NICE and ESC guidelines
What are symptoms of total Ant circulation stroke? What is the definition of partial Ant circ stroke?
Unilateral weakness +/- sensory defecit
Homonymous hemianopia
Higher cerebral dysfn (dysphasia, visuospatial disorder)
PACS is 2 of 3 of above
What are the signs of posterior circulation stroke POCS?
LOC, isolated homonymous hemianopia, cerebellar symptoms, brainstem signs
What are the cerebellar signs?
Ataxia, dysphagia, dysphonia, nystagmus
Lacuna infarcts (LACS) present how?
A subcortica stroke due to small vessel disease- unilateral weakness, pure sensory stroke or ataxic hemiparesis
How does malignant MCA infarct present and progress?
severe hemiparetic stroke with oedema within 24-48 hours causing raised ICP
How does carotid artery dissection usually present
Young people after trauma, headache and neck pain, Horner’s syndrome and CN palsies
What are the groups of pulmonary hypertension set out by Dana Point classification in 2008
6 groups
Group 1- PAH- idiopathic, congenital or disease related
1’- secondary pulm venous hypertension (occlusive disease)
2- secondary L heart failure
3- secondary chronic hypoxia or chronic lung disease
4- secondary chronic thromboemobolic disease
5- unknown or secondary multiple mechanisms (haem, vasculitic, metabolic)
What did the TRICC study look at and find?
‘Transfusion req in CC’ tested transfusion trigger 70 (aim 70-90) vs 100g/dl (aim 100-120) with non-sig trend to reduced 30day mort in restrictive arm. Those <55 and with APACHEII <20 were statistically sig reductions subgroups.
And increase in MI and pulm oedema in liberal arm
What is the evidence for keeping Hb>100 in ACS?
one pilot study (carson, brooks et al 2013 Am heart J)
What did the TRISS study find?
70 vs 90g/dl trigger for transfusion in septic shock. Found same as TRICC there was no difference in 90day mortality
In traumatic bleeding how do you decide if you use O neg or wait for cross match?
If having transient response to fluid await crossmatch if no response switch to o-neg
How is hyperK and hyperPO4 caused in tumour lysis?
Cell lysis
How does HypoCa occur in tumour lysis?
Binds with free PO4 and deposits calcium phosphate in tissues
Why do you get hyperuricaemia in tumour lysis?
Cell breakdown releases nucleic acids which convert into uric acid
How does renal failure occur in tumour lysis syndrome?
Multifactorial but ppt of uric acid and CaPO4 in renal tubules are major contributors
How prevent tumour lysis?
Fluid and hopefully pre-treat with rasburicase/allopurinol
How treat established tumour lysis?
Correct hyperK and consider phosphate binders for PO4. RRT if needed by standard defn, Ca corrected cautiously as can worsen renal failure through CaPO4 deposition
Defn mild c.diff infection and treatment
No WBC, <3 stool/day-> PO metronidazole 10-14/7
Defn moderate c.diff and treatment
WBC 10-15 and 3-5 stool/day
Metronidazole 10-14/7
Dfn severe c.diff and treatments
WBC>15, AKI (50% up from baseline), T >38.5, severe colitis
PO vanc 125mg QDS 10-14/7 if low risk
Fidaxomicin if frail or receiving abx otherwise
Defn and treatment for life-threat c diff
shock, partial/complete ileus, toxic megacolon, CT evidence of severe disease
PO vanc 500mg QDS 10-14/7 and IV metronidazole TDS
What are inclusion criteria for ECMO?
Murray score >/=3, >/=2.5 and deteriorating quickly, uncomp resp acidosis pH<7.2 or bronchopleural fistula
Exclusion criteria for ECMO?
High vent support >7/7 inc PIP >30 FiO2>0.8
Sig co-morbidity
Contra-indication to anticoag
How do you calcualte the Murray score?
The score for each of the below components divided by the number of components
Score 0-4 for:
CXR quadrants involved (0=0, 4=4)
Compliance (Vt/Pplat-PEEP) (0=>80, 60-79, 40-59, 20-39,4=<20)
PEEP- 5=0, 6-8, 9-11, 12-14, 4->14)
PF ratio- >40=0, 30-40, 23.3-30, 13.3-23.3, < 13.2=4
What are predictors of difficult to BVM?
M- mask seal-beard etc O- obesity/obstruction A- age>55 N -No teeth S- sleep apnoea/stiff lungs
How many attempts at intubation should be tried before proceding to LMA in RSI?
3
What are subtypes of COPD and how do they manifest?
Chronic bronchitis and empysematous change. The former are at risk of CO2 retension, pulm HTN and sleep apnoea.
THe latter have high work of breathing and hyperinflation
Berlin criteria for ARDS?
Within a week of known trigger or start of resp symptoms
Bilateral infiltrates in 2 or more quadrants
Not fully explained by another cause
Definition of mild, mod and severe ARDS?
PEEP 5 or more
Mild- PF 200-300 (26.7-40kPa)
Mod- 100-200 (13.4-26.6)
Severe <100 (<13.3)
Causes of ARDS
Direct (inside lung) and indirect (outside lung)
What cells produce stomach acid?
Parietal cells make HCl
What do Chief cells produce in stomach?
Pepsinogen which is activated to pepsin a proteolytic by acid conditions
What hormones promote acid environment in stomach>
gastrin, histamine and parasymp system
What hormonoes inibit acid production in stomach?
Somatostatin, PGE2, PPI/H2 blocker, anti-muscurinics
How does pyloric stenosis result in hypoK?
As the body wants H+ it exchanges K+ for H+ in distal tubule
What is in hospital mort for first SBP and 1 year mort?
1st presentation 20%, 1 year mort 30-90% depending on where on the journey the patient is. SBP should be a trigger for liver transplant consideration
What bacteria cause SBP?
E.coli (40%)
also klebsiella
Less likely G+ve cocci like strep and enterococcus
Definition of cardiogenic shock
inadequate tissue perfusion secondary cardiac dysfn
BP<90mmHg, pulm oedema, signs imparied perfusion
Haemodynamic definition of cardiogenic shock
CI<2.2l/min/m2, wedge pressure >18mmHg
What drug is a good choice in shock secondary AMI?
Levosimendan (inc availablity of intracelluar Ca) is an inotrope that doesn’t increase myocardial O2 demand but in practice NA and Dobutamine are commonly use.
What did IABP-SHOCK-II trial show?
no improvement in 12 month mort with use of IABP in patients undergoing early re-vascularisation so IABP not used
Signs of life threatening asthma?
reduced resp effort, silent chest, arrhythmia, reduced GCS, hypoxia, normal PaCO2, hypotension, PEF<33%
Signs of severe asthma?
PEF 33-50%, HR >110, RR >25, unable to speak in sentences
What is the RR reduction of failure and of complications in USS CVC insertion vs landmark?
Failure 86% reduction with 41% reduction in first pass success (IJV)
Complications 57% reduction (90% reduction in subclavian complications!)
Descending from diaphragm what are the main arterial outlets from aorta in abdomen?
Phrenic artery Coeliac trunk Supra-renal art SMA and renal arteries Gonadal IMA Iliacs
What are the branches of the coeliac trunk
on L splenic art and coming off at about 1o’clock the L gastric artery
on R common hepatic which gives off gastroduodenal (greater curve and joins splenic) and right gastric which joins the L gastric and supplies the lesser curve. R common hepatic then becomes the hepatic proper
What study demonstrated non-inferiority of Rivaroxiban and Warfarin/LMWH
EINSTEIN-PE
What score is used to assess risk of bleeding from anticoagulation as OP? What are it’s constituents?
HAS-BLED
HTN, renal disease (Cr>200), Liver disease (TB x2 and ALTx3), stroke, major bleeding or concern, labile INR, >65, anti-plt/NSAID, alcohol >8 ‘drinks’/wk
what is NICE guideline for IVC filters?
Not recommeneded unless confirmed PE and anticoag is contra-indicated. Should be removed as soon as anti-coag starts
If PE diagnosed, anticoag given and dyspnoea/functional limation persists at 3-6/12 what pathway should be followed?
ESC PE guidelines suggest TTE for anyone with symptoms or those at high risk of CTEPH. Probability of pulm HTN is then rated low, medium,high. If intermediate do BNP, CPET and consider if risk for CTEPH high any one requires VQ scan and if defect for pulm HTN specialist work up
What are risk factors for CTEPH
T4 replacement, malignancy, prev or recurrent VTE, anti-phos, infected pacemaker, splenectomy, non-O blood groups
Head and neck (usually extra-cranial) dissections account for 20% of all strokes between 20-45. What are the risk factors?
Classically think of trauma but also chest infectinos, smoking, HTN, OCP but also Ehler’s-Danlos, high homocysteine levels and alpha 1 def.
How do extra-cranial internal carotid artery dissections present?
the commonest type of head/neck dissection 2.5% of all first strokes.
Classic triad:
1. Pain on side of head, face, neck
2. partial Horner’s
3.followed in hours/days later by cerebral/retinal ischaemia (intimal tear causes clot and emobolism)
Why is the vertebral artery most likely to dissect in trauma?
Most mobile of arteries and likely to go at C1/2
Whats the evidence for treating carotid/vertebral artery dissection with antiplt/warfarin to prevent embolic events?
None, no RCT. A trend toward more events in aspirin only but not significant. Who knows whats best
What are the components of the APACHE II score?
A-Age B- RR, FiO2 C- HR, MAP D- GCS E- Temp Bloods- WBC pH, Na, K, Cr, AKI (clnical judgement), hct
what are the qSOFA criteria?
GCS <15, RR>/=22, SBP <100
2 or more= 10% hosp mort
Definition of sepsis?
Life threatening organ dysfunction caused by disregulated host response to infection
How is organ dysfunction defined in sepsis 3 defn?
EIther 2 or more points on qSOFA
How is septic shock defined in sepsis 3?
pressor to maintain map 65, lactate >2 and not hypovolaemic
What did the ALBIOS study find?
ALBIOS comapred albumin 20% and crystalloid with crystalloid alone. No mortality benefit for aiming albumin >30 but was safe.
What subset is ALBIOS knowns for?
In a post-hoc subset analysis there was a significant mortality benefit to those with septic shock. That was the same for sepis-2 and sepsis 3 criteria
What did CESAR looks at?
Is ECMO safe, efficacious and cost-effective cf standard practice?
Findings and limitations of CESAR?
Single centre really, sig cross-over and poor followup data. Only recommendation is Murray>3 or pH<7.2 despite optimum vent (lung protective) should be referred to ECMO centre
According to DAS, how many intubation attempts?
3, changing something with each attempt, +1 from a more qualified person
What interventions after Loraz and phenytoin in status epilepticus?
Propofol induction
Then Midaz 0.1-0.2mg/kg bolus followed by 0.05-0.5mg/kg/hr
Then Thio
Define status epilepticus and refractory status
Status is seizure for over 30min despite mx or multiple seizures within 30min without recovery
REfractory 30-90min
What is the management of status epilepticus in children?
Loraz 0.1mg/kg
Phenyoin 20mg.kg over 20min
Can give Praldehyde 0.8mg.kg if required
Why do cirrhotic patients hold onto (or not excrete enough) Na?
Splanchnic arterial vasodilatation from portal htn causes a decrease in effective arterial blood volume with activation of the sympathetic system and up-regulation of RAAS.
What does a SAAG >11 g/L mean in terms of ascites?
97% accuracy of saying it is due to portal HTN
Why measure total protein in ascitic tap?
If <15g/L at high risk of SBP and may benefit from prophylactic abx
With development of ascites there is a 40% 1 year mortality. What are the predictive factors that would mean poor prognosis?
HypoNa, low BP, inc Creatinine, low urine Na (note only creatinine in MELD and none in CPugh)
What diuretics for ascites?
First presentation Spiro 100->400mg then Furosemide. If recurrent give 100 Sprio, 40 furosemide and increase both stepwise over 7 days
What is the cutoff for positive neutrophil count for SBP?
250cells/mm3 though it is more specific at 500
What are the common organisms to cause SBP>
Culture +ve in only 40%
E.coli, strep and enterococci most likely
What is bacterascites?
When WBC <250 but positive culture. If other signs/symptoms treat otherwise re-sample
What’s first line abx for SBP according to EASL 2010 guideline?
cepholasporin- mostly cefotaxime though Taz is what I have seen used
When may albumin be useful in SBP?
HRS in 30% with abx only, but reduces to 10% if 1.5g/kg on day 1 and 1g/kg on day 3 if TB at baseline >68 and Cr >88. Not a great study so A2 guideline
Define hepatorenal syndrome
occurrence of renal failure in a patient with advanced liver diseas in the abscence of a cause for renal failure
Criteria for HRS diagnosis?
Cirrhosis with ascites Cr >133 no shock, no hypovolaemia Albumin 1g/kg/day for 2 days tried No nephrotxics NO renal parenchymal disease
What are the four factors that contribute to HRS?
- Splanchnic arterial dilatation
- Sympathetic nervous and RAAS activation causing shift of renal auto-regulation curve and more susceptible to MAP changes
- Impaired cardiac fn secondary cirrhotic cardiomyopathy which cannot respond to 1.
- increased synthesis of vasoactive substances such as thromboxane A2 and endothelin 1
Definition of neutropenic sepsis?
<0.5 neuts and fever >38 or signs/symptoms
Symptoms hyperK
> 6.5 muscle weakness, malaise, nausea, parasthesia
What causes the characteristic changes on ECG for HyperK?
hyperpolarisation of excitable membranes
What is the earliest and most sensitive change to ECG in hyperK?
What other abnormalities eventually with same?
Tented T-waves (T>R)
Eventually wider and flat P and QRS lengthens
When do you see J waves on ECG?
hypothermia
What is the Marshall score and what is it used for?
Pancreatitis
PF ratio, Cr, BP and pH
What % of pancreatitis is severe and of those what % get ARDS?
15-20% develop severe panc
Of those 33% get ARDS and account for 60% of early deaths
What is thought to be the mechanism of ARDS in pancreastitis?
SIRS and neutrophilic activation and release of pancreatic protelytic enzymes (elastase) which then damages lung microvasc and cause third space losses in lungs
What is Well’s score for PE?
Signs of DVT (3), Alternative diag lesslikely than PE (3), Tachy (1.5),immobile >3days or surgery within 4/52 (1.5), prev VTE (1.5), Haemoptysis (1), Active cancer (1)
Therefore most emphasis on clinical exam and what clincian thinks
Score >4 ->CTPA
Well’s score for DVT?
All of equal weight (1) except last one (-2):
Reason for it -Ca, recent immonilisation and surgery within 3/12, had it before
signs of it- localised calf ternderness, swelling of whole leg >3cm, pitting oedema in symptomatic leg, varicose veins,
Dont’ think they have it - an alternative diagnosis is at least as likely
Score >2 for USS within 4 hours
If DVT suspected using Well’s score and USS is negative what are the next steps? If the test is positive what then>
DVT -ve on USS but Well’s high then do D-dimer. If positive repeat scan in 1/52
When should local thrombolysis be offered to someone with a ilio-femoral DVT?
If they’ve had it for less than 2 weeks and are low risk of bleeding with at leat 1 year of life expectancy.
When would you use heparin in DIC?
For thrombotic complications usually chroni
What are the transfusion thresholds in DIC for plt and FFP
If bleeding correct plt if <50, if not replace when <20. If overtly bleeding correction with FFP appropriate
What is the triad of DIC?
Fibrin deposion, plt aggregation and microvasc occlusion
What bacteria are more likely to cause DIC?
G-ve and those that produce endo-toxins
What are non-infective causes of DIC?
trauma, burns, long-bone fractures, obstetric complictations (eclampsia, amniotic embolus), malignancy, transplant rejection
What is the mechanism of DIC?
Thought to feature one or more pro-coagulant factor such as intra-cellular contents, endoxtoin, tissue factor or lipopolysaccharide
What is the key to treat DIC?
Treat the cause
What heparin is used in DIC if microvascular clots predominate?
LMWH rather than UFH
What is dose of Thiopentone?
1-5mg/kg
Which causes more hypotension Thiopentone or Propofol?
Propofol
What are the classes of lactataemia?
Type A and B
What is the cause of type A lactataemia?
increased production due to lack of O2 for whatever reason (hypoperfusion, severe anaeamia, exercise, CO poisoning)
What are the causes of type B lactataemia? What are the subcategories?
Non- hypoperfusion
B1- underlying disease such as phaeo, leukaemia, organ failures, pancreatitis, short bowel
B2- drugs (Beta agonists, arenaline, alcohol, bacterial endotoxins, paracetamol)
B3 - inborn errors of metabolism
Lactate is produced from glycolysis, what can that sometimes cause a lactataemia?
Endogeous of exog catecholaemines increase glyolysis, along with sepsis and trauma/burns so more lactate is made
Lactate is also made anaerobically from pyruvate. What states increase pyruvate concentrations therefore pre-disposing to lactate formation?
Thiamine deficiency, critical illness, malignancy esp lymphoma and leukaemia
Where is lacate metabolised?
Largely 70% liver but also anywhere with mitochondira. Renal is only 5% but can go up when lactaemia is present.
How does phentolamine work?
Predom alpha 1 receptors
How does methyldopa exert its cardiovascular effects?
Alpha 2 receptors reducing SVR
How does increasing alpha 2 receptor agnoism affect SVR?
Reduces NA production
List some Alpha 1 receptor blockers
phentolamine, phenoxybenzamine, prazocin
List some alpha 2 blockers
methyldopa and clonidine
What drugs work by increasing locally produced nitric oxide?
GTN, ISMN causes direct relaxation of smooth muscle tone
How to Beta blockers work?
act on G-protein coupled adrenoreceptors which competitively inhibiting cell membrance receptor which in turn reduces cAMP and reduction of intracellular Ca therefore reduces contractility.
What is the acute treatment for thombotic stroke once thrombolysis complete? When should statins be started?
Aspirin 300mg for 2/52
No statin in acute phase
(PPI only if previous dyspepsia wiht aspriin)
What is the BODE index and how is each part scored?
Used in mortality prediction in COPD
B-BMI <21 (1),
O- obstructive FEV1 >65% (0), 50-64% (1), 36-49% (2), <35% (3)
D- Dyspnoea MMRC dyspnoea scale dysp on walking on flat (1), stops after 100yds/ few min (2), housebound on dressing (3)
E- 6min ET- >350m (0), 250-349 (1), 150-249 (2), < 149 (3)
What is the mortality associated with acute TTP?
10% though another card says 50% which seems more plausible
What is the cause of primary TTP?
related to enzyme deficiency in breakdown pathway for large von Willibrand factor multimers leading to plt aggregationand microvas coag
Causes of acquired TTP?
idiopathic (autoimmune), malig, HIV, preg, drugs (immunosuppressants, antiplt agents)
What are the forms of MAHA?
TTP, HUS, DIC, HELLP
Classic presentaion of TTP
Fever, neuro symptoms, renal failure (with MAHA and thrombocytopenai)
Treatment of TTP?
Plasma exchange but can use steroids, stop when normalised bloods. Plt treatment avoided unless life threatening bleed.
If plasma exchange and steroids are already in use for TTP what else can be added in extremis?
Rituximab (steroid sparing and as adjunct)
What does SDD (selective decontamination of the digestive tract) target?
15 most common pathogens on ICU:
MSSA, s.pneumonia, H. influenzae, maroxella, e.coli, candida all normal flora. And abdnormal flora Klebsiella, Enterobacter, Citrobacter, Serratia, Proteus, Morganella, Pseudomonas, Acinetobacter, MRSA
What is SDD (selecgive decontam digestive tract)
The idea from 80s is to prevent overgrowth of 15 common pathogens and has been shown to reduce infections in ICU (means infections are overgrowth of flora). Cost and resistance means its not really used.
What is the SDD protocol?
4/7 PO cefotaxime 100mg/kg/day! And PO tobramycin, amphotericin B, polymyxin and Vancomycin
What are the CSF variables normally?
Open pressure <20, clear, glucose 2/3 blood, protein 35mg/dl, WCC 0-3, no cells predominate
What are the CSF variables seen in viral meningitis?
Normal/high open pressure, clear, normal glucose, 50-100mg/dl protein, 5-1000 WCC lymphocytes
What are the CSF variables in bacterial meningitis?
Opening pressure high, cloudy, low glucose, >100 protein, 100-50K WCC mostly neurophils
What does fungal meningitis look like on CSF?
Very high opening pressure, clear or cloudy, low-normal glucose with 20-50 protein, 0-1000 WCC mostly lymphoctes
What does a TB CSF sample come back with from lab?
High opening pressure, yellow colour, very low glucose, 100-500 protein and 25-500 WCC mostly lyphocytes
How does TB meningitis usually present?
Insidious course over weeks, similar story to acute meningitis, chronic headache, low grade fever
What viruses commonly cause meningitis?
enterovirus, HSV, chicken pox, HIV, mumps
What organisms cause meningitis <3months of age?
G B strep, E.Coli, Listeria, Neiserria, S. pneumonia, S. aureus
What organisms cause meningitis in children?
Neiserria, H. influ, s. pneumonia
What organisms cuase meningitis in adults?
S. pneumonia, N meningitidis, s.auraus, Listeria (>65), Klebiella
What organisms more likely to cause meningitis post trauma and in neurosurgical settings?
Aerobic G-ve eg E.coli
What is the incidence of N.meningitidis, s.pnuemonia, s.aureus causing meningitis?
22% N.men
18% S.pneumoina
10% S. Aureus
5% both E.coli and GBS
What are the complications and the incidence of complications in ECMO?
Major bleed 41%, Death 40%, sign infection 30%, circuit clot 19%, lower limb iscahemia 17% oxygenator failure 15%, compartment syndrome 10%, stroke 9%,DVT, 8%, LL amputation 5%, ICH 2%, air embolus 2%, major vessel rupture 2%
When would you do a pleural fluid amylase?
Pancreatic or oesophageal pathology
Causes of exudative pleural effusion
Malig, pneumina, TB, PE, autoimmune such as RA, asbestosis, pancreatitis
When would you do a pleural fluid pH?
If suspect inection/empyema
When is glucose a useful test of pleural fluid?
If RA suspected (usually young men early in disease) would be low
When is CT warranted in pleural effusion?
CT with pleural enhancement should be done before drainage in all complicated infective and undiagnosed exudative effusions
What are the four main categories of indication for PPM?
Brady 2 nodal dysfn
Avoidance or treatment of arrhythmia (overdirve eg)
CV optimisation
Specific conditions like heart transplant
What % population have a PFO?
20-30%
What is the sensitivity of TTE and TOE for IE?
TTE 50%, TOE 90-100%
Which heart chamber is usually affected first in pericardial effusion?
RA filling
What two wavelengths of light are used in pulse oximetry?
660 (deoxy) and 940nm (oxy)
What are the findings in TURP syndrome?
Hyponatraemia from fluid absorption and glycine toxicity, most people absob 1L during procedure
TURP syndrome is caused by irrigation fluid, why is the fluid so hypotonic?
Electrolytes would make it conduct the diathermy current
What is the loading and infusion rate of aminophylline in asthma?
5mg/kg over 20min then 0.5mg/kg/hr
What is the frequency of a persistent left SVC?
0.5% of population, higher in those with cardiac defects where it can be 1:5
Where do persistent L SVC usually drain?
Coronary sinus usually but can go straight into LA
The commonest cause of nec fasciitis? And other causes?
Group A strep (60%) (and group B, S. aureus and coliforms such as Klebsiella, Enterobacter and E.coli
Why is Clindamycin included in first line regimen for nec fasc?
It has an additional benefit over penetrance that it reduces the production of strep super-antigen
What are the treatment priorities as listed in the guideline for anaphylaxis?
- Remove trigger
- IM adrenalin
- High flow O2
- IV fluid challenge
Give afferent and efferent CN for the following reflex 1. pupillary light 2. corneal 3. oculovestibular 4. Gag 5. Cough 6 Motor response to pain
- II and III
- V and VII
- VIII, III IV and VI
- IX and X
- X and X
- V abd VII
If only one ear is available for the oculovestibular reflex can the test be conducted?
Yes
What is the starting CO2 in an apnoea test for brainstem testing?
> 6 or >6.5 if a chronic retainer
What must happen to CO2 and pH in apnoea brainstem death test for it to be failed by a dead patient?
pH <7.4 and pCO2 >0.5kPa cf start
What are the points of the Glasgow-Imrie score?
PANCREAS pO2<7.9 Age>55 Neut>15 Ca <2 Renal Ur >16 Enzyme LDH >600 ALb <32 Sugar >10
PPV 79%
The transition point is between score 3 and 4
What are the types of acute pancreatitis?
Necrotising and intersitial oedematous
What is required for diagnosis of pancreatitis?
Two of
1. typical history and pain, 2. Amylase at least 3x normal, 3. characteristic findings on CT/MRI
In what situation is the amylase likely to be less than 3x normal in someone who has pancreatitis?
If they are are a delayed presentation
What percentage of people with acute pancreatitis have necrotising pancreatitis?
5-10%
Is there a link between the extent of pancreatic necrosis and the probability of it becoming infected?
No
What gives the most reliably early indicator of mortality in pancreatitis?
Persistent organ failures, not the presence of absence of local complications of the pancreatitis itself
What is the modified Marshall score and when is it used?
Pancreatitis, can be done daily
PF ratio, renal function and BP off inotropes, score 2 or more means persistent organ failure which confers a mortality risk
Define pancreatic pseudocyst
A walled off collection outside the body of the pancreas only can be called such 4 weeks after initial symptoms
What is CARS?
Compesnatory anti-inflam response syndrome (can increase risk of infection apparently)
Should pancreatitics be NBM
No unless good reason, start feed within 72 hrs, anecdotal to give NJ as better tolerated
What are the three underlying pathological causes of pancreatitis and some examples of each?
- Ductal dysfunction- GS, malig, post ERCP (alcohol)
- Acinar injury - trauma, ischaemia, drugs (alcohol)
- Defective intracellular transport- hyperCa, hypertrigs (alcohol)
What is the sequence of events leading to pancreastitis?
Acinar cell damage leads to early conversion of trysinogen to trypsin and local digestion
There are three phenotypes of DIC what are they and what is the underlying pathophysiology?
You can have high fibrinolysis (bleeding) or high thrombosis (clots). The former usually seen in malignancy particularly haematological and results in bleeding, the latter in sepsis (and results in organ failure due to microvascular thombi). If however you have both you get massive bleeding and a consumptive picture. You can have a little bit of either which is termed pre-DIC
What does Pre-DIC look like and is it worth treating
Difficult to identify but it is worth treating
What is the scoring system for DIC and what values are included?
ISTH overt-DIC
Plt count, D-dimer, PT and Klauss
When is heparin given in DIC?
When microvessel thrombosis dominates, not when someone is bleeding. Small RCT favours LMWH with Xa measurements
What should be done with VTE prophylaxis in DIC?
Cont it
GIven DIC is partly microvessel thombi can you give TXA?
Yes if the bleeding/major bleeding phenotype
What is the untreated mortality of TTP?
90%, even with treatment the mortality is still 50%, half of which in the first 24hrs of presentation
TTP can be congenital and acquired, what does ADAMTS13 do that makes its absence pathognomonic?
ADAMTS13 cleaves ultra large vWF, if it’s absent then the ultra large structure causes massive shear forces and major platelet activation and aggregation in all organ systems
What is the pentad of TTP symptoms and signs? What are its short comings?
Thrombocytopenia, MAHA, neuro symptoms, renal impairment and fever. 35 % of people don’t have neuro features at presentation and fever and renal impairment are variable.
If you are convinced you have TTP but early need for RRT what may be the alternative diagnosis?
Unusual for TTP to need RRT straight away, consider HUS
Whats issue with not being able to use pupillary reflexes in brainstem death testing?
Its the only mid-brain nerves we test
Apart from pentad of signs and symptoms of TTP what other issue can the patient have?
Abdo pain from mesenteric ischaemia
What is seen on blood film in TTP?
Schistocytes
Why test troponin in TTP work up?
Sinister sign of coronary occlusion and is a leading cause of early death
What can cause a false positive ADAMTS13 result?
Activity usually low <40% but >5% in uraemia, sepsis, post op, pregnancy
What viruses do you look for in TTP workup?
Autoimmine screen and also HIV, HAV, HBV and HCV
When is TTP particularly difficult to diagnose?
Post-partum, 25% of all TTP is pregnancy related. Seems to be more neuro involvement and less renal cf HUS
Which drugs should be avoided in TTP because they may be the cause or ppt another attack?
Quinine and oestrogen containing OCP
Which cell type of malignancy is most associated with TTP
adenoca
What is treatment for diarrhoea +ve HUS and diarrhoea -ve
D+ve is supportive +/- RRT secondary verotoxin
D-ve is similar to TTP and is treated with PEX and eculizumab
What dose of steroid would you give alongside PEX in TTP?
1g Methylpred BD for 3/7 or 1mg/kg/d pred
When is Rituximab considered in TTP?
If neuro symptoms on admission
What is the tira of HUS?
MAHA, thrombocytopenia and renal failure
Do you need a PPM if you have a sinus pause during sleep test for OSA?
No it is usually reversible as long as no symptoms
Which AV blocks require PPM?
3rd degree and any second degree with symptoms even if the bradycardia is iatrogenic because of meds needed for something else.
Also any AV block that has a pause >3s even without symptoms or any escape rate <40 even if asymptomatic
If you have 2nd or 3rd degree HB with AF when would you insert PPM?
If you have a pause of 5 or more seconds
What about a PPM if AV block only present during exercise?
Yes, PPM needed as long as there is no inducible ischaemia
What is pacemaker syndrome?
No universal definition but is the loss of improvement in symptoms due to the pacemaker. Used to be single wires cause AV dissassociation and retrograde flow. Now can happen if threshold for capture changes (usually in A lead as we would notice if the V lead stopped doing its thing). This leads to the same thing, AV dissassociation
Is PPM needed in 1st degree HB?
Not usually but if PR>0.3s then yes
If you have a bundle branch block is PPM indicated?
No unless the bundle branch block is alternating the caveat being that you must also be asymptomatic. If symptoms for any weirdness then PPM should be considered
If you’re post MI and have a transient 3rd or 2nd degree block what should be done?
As EP study may be needed + PPM or simply a PPM
Carotid sinus becomes more sensitive with age and may ppt syncope, when would PPM be advised?
When pause >3s or sig bradycardia from spont carotid pressure or on tilt table
When would you use overdrive pacing?
When someone has SVT or VT that is demonstrably terminated by overdriving after ablation and drugs have failed
When is cardiac resynch therapy indicated?
Someone who is NYHA III or IV with LVEF<35% and QRS>0.12s and SR (class I), and AF (class II recommendation). CRT with or without defib is equal though with defib may be better we don’t know. If you’re putting in a PPM for something else and the above applies by NYHA I or II CRT should be considered
When is PPM useful in HOCM?
If given with a small AV delay the LVOT gradient is reduced (most useful if grad >30mmHg at rest or>50 on exercise) and even when pacing removed it persisted meaning remodelling may have occurred. That said subsequent RCT showed ++ placebo effect and no objective correlation
What are the class I indications for ICDs
Anyone who survives a VF or VT arrest/instability if no completely reversible cause
Structural heart disease if VT even if stable
VT on ESP but unexplained symptoms
LVEF<35% with MI after40 days if NYHA IIor III or <30% and NYHA I
Non ischaemic DCM with EF<35% and NYHA II or III
What are the main differences between child and adult airways?
Children- narrowest point immediately below vocal cords and is most open in the neutral rather than head tilt position. Children have larger tongues and nasal passages are smaller
If you are a lone resus responder to an arrested child what should you do? Why is that different to adults?
Check for signs of life if safe, then give five rescue breaths and check for life again. If not then do 1min CPR before going to get help.
Adults you should go for help before CPR because you need a defib
What drugs are most likely to cause long QTc?
Anti-dysrhythmics class Ia and III are most likely. Sotalol (and quinidine) causes Torsades in 2-4% of patients receiving it. Amiod does prolong QTc but TdP is unlikely
Amiodarone causes long QT as often as Sotalol (2-4%) why do we use Amiodarone and not really Sotalol?
Sotalol degenerates into TdP, Amiodarone less so
Give some drugs commonly used in ICU that cause long QTc
TCA and SSR Cipro, Erythro (etc), metronidazole,co-trimox Haloperidol Ondansetron Dexmetatomidine
What size molecules down haemodialysis filter?
Small molecules
What size molecules does haemofiltration filter?
Medium and large molecules using convection
What are the characteristics of drugs that are more easily cleared by RRT?
Vol dist <1l/kg Low protein binding High water solubility up to 40kDa (only 500Da by dialysis) low endogenous clearance (<4ml/min/kg) extraction ratio exceeds endogenous elimination
What common toxins can be cleared by RRT?
Salicylates Li Theophy/Aminoph Alcohols Ethylene glycol Some BB (sotalol, atenolol) Anticonvulsants (cabemaz, phenytoin, Na val) Abx- most B lactams, aminoglycosides and metronidazole metformin MTX paraquat and mushroom toxin
What is a common definition of major trauma?
ISS>15
What is the estimated blood loss for each class of haemorrhagic shock?
Class 1-4
- <750ml (<15%)
- 750-1500 (15-30%)
- 1500-2000 (30-40%)
- > 2l (>40%)
How does HR vary in haemorrhagic shock for each class (in general)?
Class:
- <100bopm
- 100-120
- 120-140
- > 140
What classes of haemorrhagic shock generally have hypotension?
Class 3 or 4
What RR would you expect in each class of haemorrhagic shock?
Class 1 normal
2 20-30
3 30-40 and class 4 >40
What are the main risk factors for a significant (>2g Hb drop with transfusion requirement) in ICU stress ulcers
48hrs ventilated for resp failure (OR 15.6) Coagulopathy (OR 4.3) Other causes are: head injury spinal trauma and polytrauma Major >35% burn renal/hepatic failure severe sepsis/shock Organ transplant Steroids Previous ulcer
What are the strong inhibitors of cytochrome p450 with regards to warfarin?
Fluconzole
In SAH what BP should you aim for?
BP<160
What is the advantage of coiling SAH over clipping?
If both technically possible then coiling increases the rate of independent survivors by at least 7 years!
Should TXA be used in SAH if coiling is delayed?
Yes but side effects outweigh benefits if started after 48hrs or if cont for more than 72hr
How does Nimodipine reduce neurological deficit in SAH>
Vasospasm is no reduced, the effect is through another unknown mechanism
Phenytoin not recommended as prophylaxis in SAH but what duration of non-phenytoin agent is allowed?
3-7 days
How do you calculate a child’s weight based on age between ages 1-5(APLS calculation) What weight would you expect for a 4 year old?
weight= (2xage)+8
Therefore 16kg
How do you calculate weight when 1-12 months?
and 6-12 years?
1-12 months 0.5*age in months +4 kg
6-12 3*age +7
What is the simple weight for age calculation the resus council advocates?
(age+4) x2
What defib energy is used in children?
4J/kg
how calculate ETT size in children?
And insertion length?
age/4 +4
Length (age/2) +12
What bolus of crystaloid is given in trauma and non-trauma in children?
trauma 10ml/kg
non-trauma 20ml/kg
What is the dose of adrenalin for children?
10microg/kg
What dose of Fentayl used in children
1-5microg/kg
Which blood group is considered the universal receipient?
AB patients as they have no ABO antibodies
Patients who are Rh + can have Rh -ve blood but who should preferably not?
Women of child bearing age
If you are blood group B which blood types can you receive?
O and B
What are Duke’s major criteria for IE?
Major and minor
Major- positive blood culture typically causing IE (HACEK) from two sources 12 hours apart, positive TTE
What constitutes a positive TTE for IE?
Oscillating mass on a valve without an alternative anatomical explanation or abscess seen
New partial dehiscence of prosthetic valve
New regurg