Rote learning Flashcards
What are the 6 risk factors in Lee’s RCRI?
Hx coronary artery disease
Cerebrovascular disease
CCF
insulin-dependent DM
Pre-op Cr >177micromol/L
surgery: suprainguinal vascular or intra-peritoneal or intrathoracic
What are the % risk MACE (MI, cardiac arrest or death) with each point on the RCRI? Why may these be higher than the original numbers?
0=3.9%
1=6%
2=10%
3+=15%
The original studies used CK & excluded emergency pts; more recent external validation studies used the more sensitive troponin & included some emergency pts
What are the thresholds for BNP & NT-pro-BNP which are associated with significantly increased risk of 30-day death or nonfatal MI?
> =92mg/L for BNP & >=300mg/L for NT-proBNP
What are the tube sizes for paediatrics?
Neonate <3kg is size 3 uncuffed
>3kg= size 3 cuffed (micro-cuff)
6/12 size 3.5 cuffed
18/12 size 4
from 2, age/4 + 4 (but minus 1 for cuff)
Essentials for SAQs
Address THE QUESTION through:
What’s the main issue/concern/conflict
Timing (emergent/urgent/elective) for optimisation
Risk stratification & informed consent
WHERE is the surgery (eg. tertiary centre, daylight hours cathlab/cardiology available)
What’s the WHO (from NYHA) functional classification for pulmonary hypertension?
Class I Patients with pulmonary hypertension but without resulting limitation of physical activity. Ordinary physical activity does not cause undue dyspnea or fatigue, chest pain or near syncope.
Class II Patients with pulmonary hypertension resulting in a slight limitation of physical activity. They are comfortable at rest. Ordinary physical activity causes undue dyspnea or fatigue, chest pain or near syncope.
Class III Patients with pulmonary hypertension resulting in marked limitation of physical activity. They are comfortable at rest. Less than ordinary activity causes undue dyspnea or fatigue, chest pain or near syncope.
Class IV Patients with pulmonary hypertension with inability to carry out any physical activity without symptoms. These patients manifest signs of right heart failure. Dyspnea and/or fatigue may even be present at rest. Discomfort is increased by any physical activity.
What’s the mortality for pts with pulmonary HTN undergoing non-cardiac surg? morbidity?
What accounts for 60% of cases of periop mortality in pulmonary HTN?
1-18%
15-40%
Respiratory failure
What’s the updated definition of pulmonary HTN? What are the traditional cutoff values for grading severity of pulmonary HTN via the gold standard (PA catheterisation)? which pressure used?
MEAN pulmonary artery pressure >20mmHg & PVR >=3 wood’s units
Normal PAP is 25/8 with mean 15
mild 20-40mmHg
moderate 41-55mmHg
Severe >55mmHg
What distance on the 6MWT is considered significantly elevated M/M?
<=300m
TAPSE Cut-off values suggested for echocardiography?
TAPSE <17 mm indicates right ventricular systolic dysfunction
TAPSE <14 mm indicates a poor prognosis in patients with chronic heart failure
What VO2 max is 600m on the 6MWT?
15mL/kg/min
Definition of pulmonary HTN?
mPAP >=20mmHg on resting R) heart Cath
what recipe for PVB catheter?
0.2% ropivacaine, 20mL boluses 3-hourly
What are the STOP-BANG cutoffs?
low <3
intermediate risk 3-4
high risk >=5
How does STOP-BANG score correlate with risk of OSA?
Score 3 vs. 0-2, risk of OSA is 2.5 fold
4 vs. 0-2, OSA risk 3 fold
5 vs. 0-2, OSA risk 5 fold.
6 vs. 0-2, OSA risk 6 fold.
7 or 8 vs. 0-2, risk OSA 7 fold.
What are the AHI cutoffs for OSA severity on sleep study?
mild 5-14
moderate 15-30
severe >30
What are the items on the STOP-BANG questionnaire?
snore loudly
excessive daytime sleepiness
observed apnoeas?
Hypertension diagnosed?
obesity (BMI >35kg/m2)
Age >50
Neck circumference >=40cm
gender male
What’s the R-R interval with valsalva & normal values?
Ratio of the highest HR generated with valsalva (in phase 2) divided by lowest HR achieved (in phase 4) within 30 secs of the HR peak- normal >1.21, abnormal <1.10
How supplement K+ in DKA? when supplement?
10mmol K+ in 90mL Nsaline, supplement when potassium <4
What’s normal Hb for females?
120g/L
What’s co-phenylcaine?
5% lignocaine, 0.5% phenylephrine
What’s pituitary apoplexy?
acute haemorrhagic infarction of pituitary gland- where the blood supply is compromised by tumour or pregnancy. may occur with obstetric haemorrhage (Sheehan’s syndrome), major surgery, head injury, sickle cell crisis.
acute failure anterior lobe function, posterior lobe usually preserved.
severe headache, nausea & vomiting, visual field defects, cranial nerve palsies, failure of lactation in parturient.
Rx by management of adrenocortical failure (IV fluids, hydrocortisone, urgent transsphenoidal decompression).
What’s Fr size?
external diameter x3
What size bronchoscope do you need down a DLT if positioning requires confirmation?
2.5-3.5mm
What’s felypressin?
a non-catecholamine vasoconstrictor, chemically related to vasopressin, little antidiuretic or oxytocin-like actions, often added to LA such as prilocaine.
While NAdr may be useful for the “at risk” RV as it supports coronary perfusion by increasing aortic root pressure, at what doses does it increase PVR? what doses is it usually limited to for pts developing RV dysfunction?
> 0.5microg/kg/min
therefore, usually limit it to doses <0.2microg/kg/min
At what doses is vasopressin used as a vasopressor for pts with an “at risk” RV where NAdr has failed, given that vasopressin is not associated with incr PVR & may in fact be associated with decreased PVR at low doses?
1-4 units/min
At what doses is dobutamine generally given for RV failure?
2-5microg/kg/min
At what doses may dopamine be given to improve RV function in the setting of pulmonary vascular dysfunction? limitation?
<5microg/kg/min, tacchyarrhythmias
At what doses may IV milrinone augment RV function (improved contractility) with reduced RV afterload (reduce PA pressures)?
0.25-0.5microg/kg/min
What dose of digoxin may acutely improve CO by 10% in pts with RV failure without affecting HR?
1mg
what’s the change in BP (mmHg) per cmH2O?
1cmH2O = 0.75mmHg
What does biostate contain?
Human plasma-derived product, contains 50IU/mL FVIII & 100IU/mL vWF
vWF concentrates if <50IU/dL for pts with type 2 & 3 or those with type 1 where it can’t be raised with DDAVP
How prepare & administer dexmedetomidine for sedation?
into 20mL so 1mcg/mL
1mcg/kg bolus (could be 0.5mcg/kg if particularly concerned re hypoT/Brady) over 20 mins
then 0.2mcg/kg/hr (even up to 0.7mcg/kg/hr if require deep sedation eg. at stimulating points during awake craniotomy)
clear fluid guidelines?
adults up to 400mL 2hrs prior to procedure.
paediatrics: clear fluids (no > 3mL/kg/hr) up to 1hr prior to anaesthesia.
How to classify CKD?
grade 1 is GFR >=90mL/min
grade 2 is GFR 60-89mL/min
grade 3a is 45-59mL/min
grade 3b 30-44mL/min
grade 4 15-29mL/min
grade 5 <15mL/min
How to administer dantrolene?
20mg diluted into 60mL sterile water, give 2.5mg/kg total body weight
dosing for naloxone
1-4microg/kg, it comes in 0.4mg vial, dilute to 20mL
categories of hypothermia
mild 32-35degC
moderate 28-32degC
severe <28degC
NAGMA?
Methanol & other toxic alcohols
Uraemia
DKA
Pyroglutamic acidosis
Iron overdose
Lactic acidosis
Ethylene glycol
Saligylates
HAGMA?
Pancreatic secretion loss
Acetazolamide
Normal saline intoxication
Diarrhoea
Aldosterone antagonists
Renal tubular acidosis type 1
Ureteric diversion
Small bowel fistula
Hyperalimentation (TPN)
How to manage severe hypoglycaemia?
IV 25g of 50% glucose
What would you class as mild, moderate & severe hypercalcaemia?
<3mmol/L
mod 3-3.5
severe >3.5mmol/L
What would you class as mild, moderate & severe hypermagnesemia?
2-3mmol/L (nausea, flushing, headache, lethargy, drowsiness, diminished deep tendon reflexes) *for pre-eclampsia Rx, therapeutic serum [Mg++] is 1.7-3.5mmol/L
3-5mmol/L (somnolence, hypocalcaemia, absent deep tendon reflexes, hypotension, bradycardia, ecg changes)
> 5mmol/L (flaccid paralysis, apnoea, resp failure, CHB, cardiac arrest (resp failure usually precedes cardiac arrest)
Normal magnesium?
0.85-1.1mmol/L
what’s normal serum calcium (total?)
2-2.5mmol/L
At what rate should remi be run as a component of TIVA or with volatile?
0.05-0.3mcg/kg/min
How to execute cough less remi wakeup?
have remi running at >=0.1mcg/kg/min, extubate when the pt can follow commands (typically before spont resp efforts or recovery of airway reflexes)
Overall incidence of AAGA from NAP5? if no NMBD?
1 per 19,000
<1 per 130,000
Whats Adj40BW?
uses an adjustment factor of 0.4, providing an adjusted body weight in pts who are >20% of their ideal body weight, useful to account for distribution of drugs to non-lean tissues in obesity
This is:
Adj40BW = ideal body weight + (0.4 x (TBW - IBW))
How to calculate ideal body weight (the body weight associated with lowest mortality)?
height - 100 for males, 105 for females
Which drugs use ideal body weight & examples? exceptions to these rules?
water-soluble, eg: midazolam, ketamine, NDMBs, remi
exceptions= opioids & local anaesthetics, which should be based on lean and ideal body weight, respectively, in the obese
rocuronium=LBW
LMA sizing is based on ideal body weight, as are tidal volumes
How to calculate paediatric ideal body weight?
<8yo 2x age (yrs) + 9
>8: 3x age (yrs)
Nutshell summary of PADDI trial
multicentre international noninferiority trial with 8700 pts having GA for noncardiac surgery
risk SSI within 30 days of surgery similar if pts had 8mg IV dexamethasone vs placebo so do not consider risk of surgical site infection a reason to avoid dexamethasone
results similar in pts with & without diabetes
Does neostigmine significantly increase risk of PONV?
No
What are the APFEL risk factors for adults? % risk with each score?
female
non-smoker
postop opioids
Hx PONV or motion sickness
0=10%
1=20%
2=40%
3=60%
4=80%
What are the some risk factors for PONV for children? % risk with each score?
age >=3yo
Surgery >=30mins
strabismus surgery
Hx POV or FHx PONV
10%
10%
30%
50%
70%
What are pre- intra- and post-op risk factors for PONV in children in the 2020 4th Consensus Guidelines for Mx of PONV?
Pre:
Age >=3yo
post-pubertal female
Hx POV/PONV/motion sickness
FHx PONV
Intra:
strabismus surgery
otoplasty
adenotonsillectomy
surgical time >=30mins
volatiles
Postop:
long-acting opioid
What are pre- intra- and post-op risk factors for PONV in children in the 2020 4th Consensus Guidelines for Mx of PONV?
Pre:
Age >=3yo
post-pubertal female
Hx POV/PONV/motion sickness
FHx PONV
Intra:
strabismus surgery
otoplasty
adenotonsillectomy
surgical time >=30mins
volatiles
Postop:
long-acting opioid
What are pre- intra- and post-op risk factors for PONV in children in the 2020 4th Consensus Guidelines for Mx of PONV?
Pre:
Age >=3yo
post-pubertal female
Hx POV/PONV/motion sickness
FHx PONV
Intra:
strabismus surgery
otoplasty
adenotonsillectomy
surgical time >=30mins
volatiles
Postop:
long-acting opioid
which pts can’t use scopolamine patch? instructions for use? other side effects/precautions?
angle closure glaucoma
place at least 2hrs pre-induction, remove it within 24hrs postop
dry mouth, blurry vision. confusion/agitation esp in elderly or those w baseline cognitive impairment.
ondansetron paeds dosing
and dex
and metoclopramide
0.1mg/kg, up to 4mg
0.15mg/kg, up to 4mg
shouldn’t use UNLESS can’t use the other antiemetics & must NEVER use in chn <1yo (prolonged clearance). EPS 20x higher in children! if must use, 0.1mg/kg max 10mg.
Does adding droperidol to ondansetron increase the risk of QT prolongation?
the risk exists for either drug but it’s not additive
What are congenital causes of the long QT syndrome?
Jervell and Lange-Nielsen syndrome: profound bilateral sensorineural hearing loss from birth & long QT syndrome. very rare.
Romano-Ward syndrome: the most common form of congenital long QT syndrome.
Idiopathic
What are acquired causes of the long QT syndrome?
ANALGESIC/ANAESTHETIC drugs: HIGH RISK= methadone, low/mod risk= buprenorphine, low risk propofol
ANTIARRHYTHMICS: HIGH RISK= amiodarone, procainamide, quinidine, sotalol. mod risk= flecainide
ANTIANGINALS: ivabradine (low risk)
ANTIMICROBIALS: mod risk= fluconazole, macrolides. low risk= ciprofloxacin
ANTIRETROVIRALS (HIV), some antihistamines, antineoplastic drugs
BRONCHODILATORS: terbutaline mod risk, salmeterol/vilanterol/albuterol low risk
DIURETICS via electrolyte changes. rarely, PPIs via hypomagnesaemia.
GI drugs: droperidol & ordains mod risk, metoclopramide low risk
PSYCHOTROPICs: high risk= chlorpromazine, IV haloperidol, ziprasidone. mod risk= amisulpride, clozapine, olanzapine, quetiapine, risperidone, oral haloperidol, imipramine, citalopram/escitalopram. low risk= sertraline, fluoxetine.
METABOLIC: hypoK, hypoMg, hypoCa, starvation, anorexia, liquid protein diets, hypothyroidism
BRADYARRHYTHMIAS: AV block (2nd or 3rd degree), sinus node dysfunction
OTHER: hypothermia, intracranial disease, myocardial ischaemia/infarction (esp with prominent T-wave inversions, organophosphates
How long monitor ecg after droperidol?
2-3hrs
What’s aprepitant? compared with ordans?
NK-1 antagonist
equally effective for prevention of postop nausea but more effective for preventing vomiting @ 24 & 48hrs
What’s the limitation of phenothiazines?
sedation @ high doses & extrapyramidal effects
How prepare & give GTN?
50mg in 50mL 0.9% saline, commence at 3-5mL/hr & titrate to response
What is the classification of severity of DLCO reductions?
Normal: >75% predicted
mild: 60-74%
moderate: 40-59%
severe: <40%
How many segments in R) lung?
22; 6 in UL, 4 in ML, 12 in LL
How many segments in L) lung?
20; 10 in UL, 10 in LL
If a pt has an FEV1 of 2L, do we need to proceed to more sophisticated tests prior to pneumonectomy?
no, as if removing 55% of lung ( R) ), still likely to have >1L FEV1
how calculate postop predicted FEV1 or DLCO?
ppo = preop FEV1 (or DLCO) x (1 - % functional tissue resected)
what are the cutoffs for ability to proceed for ppo FEV1?
> 50% can have pneumonectomy
40% can have lobectomy
30% can have segmentectomy
What does the Austin use for periop prediction Tx surgery?
ppo FEV1 x ppo DLCO
COPD GOLD criteria?
mild FEV1 >= 80% pred
mod 50 <= < 80%
severe 30 <= <50%
very severe <30% predicted
What’s KCO?
DLCO/VA, it’s the DLCO indexed to alveolar ventilation, so if TLCO is reduced but KCO is normal, the total lung ventilation is reduced due to a mechanical issue but lung parenchyma likely OK as lung units that are being ventilated are functioning well
What are the elements of the 3-legged stool? example values?
Respiratory mechanics (eg. for lobectomy want ppo FEV1 >40%)
cardiopulmonary reserve (eg. for lobectomy VO1 max >15mLs/kg/min)
parenchymal function (eg. DLCO ppo >40%, pO2 >60mmHg, pCO2 <45mmHg)
why use DASI?
Through the METS study, was found to predict death or MI within 30/7 after major non-cardiac surgery
analgesic dose for ketamine?
0.1-0.2mg/kg/hr (68mL/hr)
how far should PVB catheter be inserted?
no >3cm (avoid migration into epidural space)
how far should PVB needle be inserted?
No >1-1.5cm beyond TP. safest to walk off bottom of TP. If go 4cm in Tx (5cm Cx or Lx) sans contact bone, come out & re-angle (risks intra-pleural puncture)
equations for predicted body weight (used for TVs in ARDs)?
males:
PBW= 50 + 0.91 x (height in centimetres - 152.4) kg
females:
= 45.5+ 0.91 x (height in cm - 152.4) kg
What’s the alveolar gas equation?
PAO2 = FiO2 x (Pb - PsvpH2O) - (PaCo2 / RQ)
What’s normal pulmonary capillary wedge pressure?
4-12mmHg
Draw the pressure traces for RA, RV, PA & PAWP?
figure 3
mnemonic for branches of lumbar plexus
I
I
Get
Leftovers
On
Fridays
mnemonic for major branches of sacral plexus
Sup gluteal
Inf gluteal
Posterior cutaneous nerve of thigh
Pudendal
Sciatic
mnemonic for branches for cervical plexus block (anticlockwise from 1 o’clock)?
Greater auricular
Lesser occipital
Accessory
Supraclavicular
Transverse cervical
What are the AHI cutoffs for adults?
OSA if >=5 events/hr
mild OSA (5-14 AHI/RDI/REI) per hour of sleep
mod OSA 15-30 events/hour
severe OSA >30 events per hour sleep
classification of OSA in children:
mild 1-4.9 RDI or AHI per hour
mod 5-9.9
severe >10
Problems with MRI?
Unfamiliar environment, personnel, equipment particularly in emergency
metal
heat
monitoring/artefact
difficult to access patient
dose for topicalisation paediatric foreign body? how long last?
7mg/kg, 30 mins
dose of remi for foreign body removal (with pt deeply anaesthetised)?
0.05mcg/kg/min
options for anaesthetising inguinal herniotomy?
GA
GA + caudal
spinal/awake
why does ex-prem need HDU postop?
monitoring for apnoeas, BGL monitoring
Where does the dural sac end in neonates?
S3
Where does the spinal cord end in neonates?
L3
risk factors for apnoeas in neonate?
FHx
lower weight, age
anaemia
hypothermia
use of opiate
premorbid resp or cardiac disease
at what point after a viral URTI is the highest risk of respiratory compromise?
D3-4
How long does a spinal last in paeds? why?
approx 1hr, higher CSF turnover limits duration, need surgeons scrubbed & ready
some signs of sleep disordered breathing in kids?
hyperactivity
parental vigilance
biochem?
polysomnography
What’s an apnoea on PSG?
90 percent or greater decrease in airflow, compared with preceding signals, for a minimum of 10 seconds
What’s a hypopnoea on PSG?
Airflow decreases at least 30 percent compared with the pre-event baseline
The diminished airflow lasts at least 10 seconds
The event is associated with either a 3 percent oxygen desaturation from baseline or an EEG arousal
protamine dosing?
1mg per 100 units heparin given
normal FRC supine & erect? normal RV? normal inspiratory capacity?
30mL/kg
40mL/kg
20mL/kg
52mL/kg (TV + IRV)
for a chronic respiratory acidosis, what bicarb expect to see?
incr HCO3- 4mmol for every 10mmHg incr PaCO2
for chronic resp alkalosis, what bicarb expect to see?
reduction of 5 for every 10mmHg drop in PaCO2
for acute resp acidosis, what bicarb expect to see?
incr 1mmol for every 10mmHg incr PaCO2 above 40mmHg
for acute resp alkalosis, what expect to see?
reduction of bicarb by 2mmol for every reduction in PaCO2 of 10mmHg
What’s normal ANION gap & how calculated?
[Na+] - ([HCO3-] + [Cl-])
normal is 12 (range 6-15)
what’s the delta ratio? when used? interpretation?
if anion gap elevated, must calculate delta ratio:
delta ratio = ( increase in AG ) / (reduction in [HCO3-]), ie. (AG - 12) / (24 - bicarb)
if the delta ratio <0.8, combined HAGMA & NAGMA
if delta ratio 1-2, it’s uncomplicated HAGMA
if delta ratio >2, there’s a pre-existing metabolic acidosis
HAGMA differentials?
Carbon monoxide, cyanide, congenital heart failure
Aminoglycosides
Toluene (glue sniffing), theophylline
Methanol
Uraemia
DKA, ETOH ketoacidosis, starvation
Paracetamol
Iron, isoniazid, inborn errors of metabolism
Lactic acidosis
Ethanol, ethylene glycol
Salicylates/aspirin
NAGMA differentials?
Urinary diversion/ureteroenterostomy
Small bowel fistula
Extra Cl
Diarrhoea
Pancreatic fistula
Acetazolamide or Addisons
RTA type 1
Tenofovir, topiramate
What’s the metabolic compensation for an acute resp acidosis?
for every 10mmHg rise PaCO2, bicarb rise by 1mmol/L
ie:
expected bicarb = 24 + ( (PaCO2 - 40) / 10)
What’s the metabolic compensation for a chronic resp acidosis?
For every 10mmHg rise in PaCO2, bicarb increases by 4mmol/L, ie:
HCO3- = 24 + (4x ((PaCO2 - 40) / 10))
What’s the metabolic compensation for an acute resp alkalosis?
for every 10mmHg reduction in PaCO2, decrease in bicarb by 2mmol/L:
HCO3- = 24 + (2x ((PaCO2-40)/10))
What’s the metabolic compensation for an chronic resp alkalosis?
for every 10mmHg reduction in PaCO2, bicarb reduces by 5:
HCO3- = 24 + (5 x (PaCo2-40)/10))
how to calculate resp compensation for metabolic acidosis?
for complete compensation, PaCO2= 1.5 x (bicarb) + 8 (margin of error +/-2mmHg tolerated)
to calculate resp compensation for metabolic alkalosis (complete compensation)?
expected PaCO2 = ((0.7 x bicarb) +20)
error margin +/-5mmHg tolerated
how to calculate RVSP from tricuspid doppler?
Simplified Bernouli equation?
RVSP = 4v2 + RAP (or CVP)
What’s the initial does of IV Adrenaline for grade II (moderate) anaphylaxis in an adult?
10-20microg (0.1-0.2mL), if no response, 50microg (0.5mL)
What’s the initial does of IV Adrenaline for grade III (severe) anaphylaxis in an adult?
50-100microg (0.5-1mL), if not responding, 200microg (2mL)
What SBP is listed on the anaphylaxis “immediate management” card for starting CPR?
SBP <50mmHg
how much crystalloid should be given as initial bolus for moderate anaphylaxis? life-threatening?
500mL
1L
what’s the paediatric adrenaline dose for cardiac arrest?
0.1mL/kg of 1:10,000 (10microg/kg)
what’s the paediatric adrenaline dose for moderate anaphylaxis?
0.1mL/kg of 20microg/ml (2mL/kg)
what’s the paediatric adrenaline dose for severe anaphylaxis?
0.2-0.5mL/kg of 20microg/mL (ie. 4-10microg/kg)
what triggers need to be removed in suspected anaphylaxis?
stop injecting
stop & disconnect synthetic colloids
chlorhex (incl chlorhex-impregnated CVCs)
latex
what’s the optimal position, under ultrasound guidance, to place a catheter tip to provide continuous erector spinae plane block for post-thoracotomy analgesia?
T5
what’s the maximum warm ischaemic time (in minutes) acceptable for procuring the lungs following donation after cardiac death?
90mins
what’s the warm ischemia time for procuring heart/liver/pancreas? kidneys? lungs?
30 mins / 60 mins / 90 mins
max cold ischaemia time various organs?
heart 4hrs / lungs 6-8hrs /liver or pancreas 6hrs DCD or 12 hrs DBD / kidneys 12hrs DCD or 18hrs DBD
what does Hartmann’s contain?
Na+ 129
Cl-109
Ca++ 2
K 5
bicarb (as lactate) 29
osmolality 274msomol/kg & pH 6.5
what does NaCl contain? tonicity cf ECF?
150 so higher Na+, approx 300msomol/L so isoosmotic (sim tonicity & osmolality) but much higher Cl- than ECF
What does plasmalyte contain?
Na+ 140mmol/L
K+ 5mmol/L
Mg++ 1.5mmol/L (3mEq)
Cl- 98mmol/L
actate 27mmol/:L
gluconate 23mmol/L
NO lactate or calcium
branches of cervical plexus?
lesser occipital
greater auricular
transverse cervical
supraclavicular
ABx for appendix?
GP & GN (eg. 2nd gen cephalosporin) and anaerobes (eg clindamycin or metronidazole)
:) how to calculate normal A-a gradient?
(age x 0.21) + 2.5
:) how calculate P/F ratio- normal? what value suggests abnormal gas exchange?
normal 300-500mmHg
<300mmHg indicates abnormal gas exchange
<200mmHg indicates severe hypoxaemia
:) hypoxaemia vs hypoxia?
hypoxaemia= reduced PaO2
hypoxia= tissue deprivation of O2
:) how to prepare & run Adr infusion?
3mg in 50mL (60microg/mL), rate is 0.1microg/kg/min, in mL/hr is microg/min (eg. 70kg runs at 7mL/hr)
Injury to which nerve may cause winged scapula?
long thoracic
which LA may be ideal for intercostal blocks?
liposomal bupivacaine
what are manifestations of niacin (vit B3) deficiency?
decreased protein synthesis, hypoalbuminaemia
pellagra (rough scaly skin, glossitis, angular stomatitis, mental confusion, diarrhoea)
from which organs does classic carcinoid typically originate? how do foregut carcinoids usually manifest?
midgut eg. appendix, jejunum, ileum, cecum, asc colon (excess serotonin from excess tryptophan metabolism)
foregut NETs more commonly produce 5-hydroxytryptophan & histamine
why is it important to distinguish carcinoid wheeze from bronchial asthma?
Mx with B agonists may–> profound vasodilation
What are CYP inducers? inhibitors?
INDUCERS:
Alcohol (chronic)
Griseofulvin
Phenytoin
Rifampicin
Smoking, StJohn’s Wort
Carbamazepine
Phenobarbital
INHIBITORS:
Cimetidine, cranberry juice, grapefruit
Omeprazole
Amiodarone, acetameniphin, antifungals/ABs (not griseofulvin, rifampicin)
Thyroid hormone
SSRIs
Pseudocholineserase abnormalities
catalyse hydrolysis of choline esters- metabolise succinylcholine & mivacurium
deficiency may be genetic (mutation on 3q26)–> sux apnoea, variable up to 8hrs, only Mx= keep I&V, wait
with normal pseudocholinesterase activity, dibucaine inhibits 80% of enzyme activity (dibucaine number 80), heterozygous atypical DN 30-65, homozygous DN 20
pseudocholinesterase activity incr in alcoholism, obesity
decr w impaired hepatic synthetic function, organophosphates, anticholinesterases, MAOs, pregnancy
premeds
midazolam po 0.3mg/kg, intranasal 0.2mg/kg
ketamine PO 2-5mg/kg IM 4-5mg/kg
dexmed 1microg/kg
clonidine po 2-4microg/kg
where does SC end in neonates? adults
L3
L1 (adult level)- reaches by 12 months of age
where dural sac end in neonate vs 12 month old?
S3-4 vs S2 by 12 months (adult level)
intercristal line level?
L5-S1 neonates vs L5 chn, L4-5 adults
APFEL score & %s
female
non-smoker
Hx PONV/motion sickness
post-op opioid
0=10%
1=20%
2=40%
3=60%
4=80%
other risks:
younger adult age
surg:
laparoscopic chole
bariatric
gynae
OT duration >60mins
aggressive prophylaxis if vomit/retch detrimental eg. raised ICP/suture compromise
anaes factors:
volatile (dose-dependent)
nitrous (duration-dependent, only risk if >1hr)
postop opioid use
post discharge N&V:
female
Hx PONV
age <50
PACU opioids
nausea in PACU
0=10% risk PDNV
1=20
2=30
3=50
4=60
5=80%
Risk minimisation for every pt:
minimise preop fast
euvolaemia
RA vs GA
prop induction/maintenance
minimise intra- & postop opioids for all w multimodal analgesia
avoid volatiles or N2O >1hr
sugammadex vs neostigmine for reversal (NNT 16 to reduce PONV risk)
how to approach prophylaxis:
consider risks/benefits of agents so judicious but scores not perfect S&S so some give 1-2 even if no risk
official advice= 1-2 risk factors, give 2 agents, high 3+ risk factors give 3-4 agents
Rx: use agents of different class to prophy
Eberhard CHN:
surg >=30mins
age >=3
strabismus surg
personal or FHx PONV
0=10%
1=10%
2=20%
3=50%
4=70%
other risks:
pt:
post-pubertal females
surg:
eye surgery
tonsillectomy
otoplasty
anaes:
use anticholinesterases
0 risk factors give 0-1 proph antiemetic
1-2 risk factors 2 methods
3+ give dex/ondans/tiva
liberal fluids
opioid sparing incl regional
clonidine or dexmed & IV paracetamol
weight prediction in paeds
SBP
fluids
tube sizes
Infants: (age(months)/2) + 4
chn 1-10: (age + 4) x2
chn >10: age x 3.3 but huge variation
SBP
(80+ (age in yrs +2)) mmHg
fluids:
maintenance 4:2:1
neonates day 1: 60mL/kg/day (alternative: give 2.5x their weight in kg mL/hr of 10% dextrose)
from day 1, the fluid is 10% dextrose w 1/4 n saline w 10mmol KCl in a 500mL bag, taking:
80mL/kg/day day2
100mL/kg/day day 3
120mL/kg/day D4 onwards
GI losses >20mL/kg, replace w 0.9% saline +10mmol KCl (from 500mL bag) mL for mL
resus 10-20mL/kg 0.9% saline
newborn size 3 (3.5kg)
1-6 months size 3.5
6-12 months size 4
2yo use size 4.5
>2, (age/4 + 4) minus 0.5 for cuff
depth:
age/2 + 12 (oral)
age/2 + 15 (nasal)
neonates depth
oral (wt in kg) +6
nasal (wt x 1.5) + 7
Fr for suction catheter:
2x ID in french gague
CVC depth is 10% of child’s length or height
Sugammadex dosing PTC:
2mg/kg if TOF=2 (but can give neo/glyco for this)
4mg/kg if 1-2 PTC but no TOF
tof tends to emerg w ptc 9
naloxone dose for suspected narc
1-4microg/kg
flumazenil dose for BZD od
5mcg/kg every 60 secs until awake
Checklist delayed emergence/hypoactive emergence delirium
residual drug effects:
sed/hypnotic (time)
NMB (sugammadex 4mg/kg if PTC 1-2 but no TOFC & if roc or vec used, 2mg/kg if TOF 2 (could use neo/glyco))
opioids (Mx naloxone 1-4microg/kg)
BZD (Mx flumazenil 5mcg/kg every 60 secs until awake)
anticholinergic (Mx physostigmine 1.25mg, a cholinergic agent)
LAST
CNS:
CVA: neuro exam, CTB (think haemorrhagic if raised ICP); maintain cerebral protection (oxygenation, ventilation to low normocapnia, CPP)
cerebral hyperperfusion syndrome if HTN & recent revascularisation
seizures; eeg, consider Hx & medication precipitants
Cerebral gas embolism
CVS:
hypotension/bleeding (echo Ax causes shock)
Metabolic:
hypoxaemia (eg. PTx, atelectasis, PE)
hypercarbia (eg. old soda lime)
hypothermia or hyperthermia
hypothyroidism
HYPOGLYCAEMIA (50mL 50% glucose= 25g)
hepatic or renal failure
electrolyte imbalance (hypocalcaemia or Mg++ correct, hypermagnesemia may need crystalloid, loop diuretic or even dialysis if renal impairment, hypercalcaemia isotonic saline, calcitonin, bisphosphonate)
acidosis
TEA vs tPVB failure rate?
15vs 6%
equivalent analgesia, no sig diff maj compns (mortality, LoS) but incr minor (hypoT, urinary retention, N&V) w TEA.
lower infusion []/rate for elderly (they require 40% less epidural solution/hr)
