Emergency Medicine Flashcards
describe treatment of anticholinergic overdose
consider charcoal if conscious
if hypotension
- fluids
- glucagon
- noradrenaline
give sodium bicarbonate if
- acidosis
- QRS >120 ms
- hypotension unresponsive to fluids
- ventricular arrhythmias
intralipid
Describe anticholinergic toxidrome
“Blind as a bat, dry as a bone, red as a beet, hot as a desert”
- flushing
- dry skin and membranes
- mydriasis and loss of accommodation
- clonus
- confusion
- hyperthermia
- tachycardia
- absent bowel sounds
- urinary retention
- constipation
e.g. tricyclic antidepressants (TCAs like amitriptyline), antipsychotics, antihistamines
> metabolic acidosis
> convulsions
> hypotension with dysrhythmia (mostly tachycardia)
> airway loss if obtunded
describe a cholinergic toxidrome
muscarinic symptoms: SLUDGE
- salivation
- lacrimation
- urination (increased)
- defecation (diarrhoea)
- GI cramping
- emesis (vomiting)
nicotinic symptoms: MTWTF
- muscle cramps
- tachycardia (or bradycardia in muscarinic)
- weakness
- twitching
- fasciculations (check tongue)
other symptoms
- miosis
- sweating
- seizure risk
- bronchorroea
- bronchospasm
most common cause - organophosphate insecticides, pesticides
also donepizole and overdose of agents used in myasthenia gravis e.g. pyridostigmine
also novichok nerve agents
antidote - atropine, pralidoxime
describe sympathomimetic toxicity
- airway compromise less common unless rigid
- tachypnoea
- hypertension and tachyarrhythmias
- mydriasis, seizure, psychosis
- hyperthermia
causes: cocaine, MDMA, significant caffeine, amphetamines, theophylline excess in asthmatics
remember to monitor CK and myoglobin
> early ECG if chest pain, cocaine can lead to ACS due to coronary vasospasm
management
- charcoal if theophylline poisoning only
- benzodiazepines e.g. diazepam if agitation/confusion
- avoid beta blockers
- cool by any means possible then IV dantrolene
- sometimes sodium nitroprusside for hypertension
describe sympathomimetic serotonergic crisis / baclofen withdrawal
also caffeine, theophylline, SSRIs/SNRIs, GHB, MDMA
- rigid jaw and airway compromise
- tachycardia, hypertension, tachypnoea
- cardiovascular collapse
- acidosis
- hypertonicity with clonus
- confused and agitated before coma
- refractory hypoglycaemia
- seizures
- rhabdomyolysis with K>10
- malignant hyperthermia
management
- intubation (without fentanyl)
- large amounts of benzodiazepines
- aggressive cooling
- cyproheptadine orally or NG
- chlorpromazine IM
describe opioid toxicity
- airway compromise
- hypoventilation and hypoxia
- hypotension and bradycardia
- reduced GCS and pinpoint pupils
- hypothermia
management
- naloxone (half-life 30 or 45 mins)
> naloxone infusion if modified release like MST
- supportive care
describe sedative / hypnotic toxicity
e.g. alcohol, benzodiazepines
- airway loss if obtunded
- respiratory compromise
- cold
- hypotension, bradycardia
- mydriasis
- dizzy, dysarthric, drowsy and ataxic
management
- watch for withdrawal (seizures)
- supportive treatment
- flumazenil only rarely
describe a paracetamol overdose
presentation
- early: nausea and vomiting
- late (3-4 days):
> nausea and vomiting
> hepatic necrosis
> hypoglycaemia
> cerebral oedema
> encephalopathy, coma, death
if plasma level >700 mg/L (rare) - different presentation
> sedation
> coma
> high lactate
reliable sign of liver damage: prolonged PT
prognostic factor: arterial blood gas pH
list adverse effects of N-acetylcysteine
- nausea
- urticaria
- erythema
- bronchospasm
- angioedema
- anaphylactoid reaction
describe beta blocker overdose
- bradycardia
- hypotension
- prolonged QTc
- cardiogenic shock: VF/VT
- coma
- seizures
- propranolol: bronchospasm
management
- activated charcoal if <1h
- 8.4% sodium bicarbonate
- atropine
- IV glucagon
- consider inotropes
- intralipid if propranolol
- ECMO
cardiac pacing ineffective
describe calcium channel blocker overdose
- sinus bradycardia
- hypotension
- prolonged QTc
- high K, low glucose
- cardiogenic shock: VF/VT
Management
- activated charcoal if <1h from ingestion
- calcium chloride
- insulin (aim for hyperinsulinaemic euglycaemia)
- 8.4% sodium bicarbonate
- intralipid
- inotropes
- ECMO
describe digoxin toxicity
- QTc prolongation
- bradycardia
- “reverse tick” on ECG
- metabolic acidosis
- hyperkalaemia
- nausea, vomiting
- confusion
management
- stop digoxin
- charcoal
- sodium bicarbonate
- insulin/dextrose for hyperkalaemia
- atropine
- give digibind if plasma level > 10 nmol/L
- cardiac pacing
- ECMO
describe iron toxicity
- nausea, vomiting
- abdominal pain
- diarrhoea
- haematemesis
- acidosis
- potential for late deterioration with hepatic necrosis
- worse in children
treatment
- gastric lavage
- endoscopy
- desferrioxamine
- dialysis
describe cannabinoid hyperemesis
- cyclical vomiting
- relieved by hot water over 41 degrees
- standard antiemetics may not work
- management
> capsaicin cream
> haloperidol
describe the RUSH protocol and HI-MAP approach
RUSH protocol
- pump: LV contractility, RV strain, tamponade
- tank: IVC variation, leaks, tank compromise
- pipe: aortic dissection, aneurysms, DVT
HI-MAP approach
- heart
- IVC
- Morrison’s pouch and E-fast
- aorta and deep veins
- pneumothorax, PLE, PN, pulmonary oedema
List causes of coma
AEIOU TIPS
- acidosis / alcohol
- epilepsy
- infection
- overdose
- uraemia
- trauma to the head
- insulin (hypoglycaemia)
- psychosis
- stroke
list causes of delirium
PINCH ME
P - pain
I - infection
N - nutrition
C - constipation
H - hydration
M - medication (new, changes, AKI?)
E - environment, everything else
> glasses, hearing aids, change of location
describe the pharmacological treatment of delirium
if all other measures have failed
- haloperidol (avoid in Parkinson’s / LBD / prolonged QTc)
- lorazepam
- avoid olanzapine or risperidone (increased risk of stroke and death)
what is the triangle of safety for ICD insertion?
- lateral edge of pectoralis major
- base of axilla
- lateral edge latissimus dorsi
- 5th intercostal space
what is the modified Parkland’s formula for calculation of fluids in burns patients
> 15% BSA in adults
BSA x weight (kg) x 4ml (fluid in 24h)
give first half of fluids (Hartmann’s) in first 8h
next half of fluids in next 16h
list the branches of the facial nerve
ten zebras bit my cock
- temporal
- zygomatic
- buccal
- mandibular
- cervical
list maximum safe doses of local anaesthetics
lidocaine: short-acting voltage-gated sodium channel blocker
> 3mg/kg
> with adrenaline 7mg/kg
> to calculate dose multiply percentage by 10 e.g. 1% lidocaine contains 10mg/ml (1g in 100ml of solution)
bupivacaine: slower onset but longer duration
> dosage 2mg/kg not changed by addition of adrenaline
levobupivacaine
> 3mg/kg
> dosage calculation example, 0.25% levobupivacaine contains 2.5mg/ml
> improved cardiac safety profile compared to bupivacaine
describe carotid artery dissection
common cause of stroke in younger patients
presentation
- local pain
- ipsilateral headache / neck pain
- ischaemic stroke
- ipsilateral Horner’s syndrome without anhidrosis
- retinal ischaemia
causes
> spontaneous: especially in connective tissue disorders e.g. Marfan’s/Ehlers-Danlos
> traumatic
> iatrogenic e.g. cerebral angiography
investigations: CT angiogram brain or MRI
management
- conservative: antiplatelets +/- anticoagulation
- gentle angioplasty and stent placement
What is the muscle relaxant of choice for Rapid Sequence Intubation (RSI)?
Suxamethonium
or rocuronium (but risk of allergy)
What is the management of Vfib according to UK Advanced Life Support Guidelines?
Chest compressions 30:2
Single shock with defibrillator
1mg IV adrenaline after 3 shocks
repeat 1mg IV adrenaline after 3-5 minutes
> 1 mg - 10ml 1:10,000 IV or 1ml 1:1000 IV
If unsuccessful 300mg amiodarone IV
after 5 shocks 150mg amiodarone IV
list reversible causes of cardiac arrest
4 H’S
- Hypoxia
- Hypovolaemia
- Hyperkalaemia, hypokalaemia, hypoglycaemia, hypocalcaemia, acidaemia & other metabolic disorders
- Hypothermia
4 T’s
- Tension pneumothorax
- Toxins
- Thrombosis (coronary or pulmonary)
- Tamponade - cardiac
Describe the clinical features and treatment of aspirin overdose
Aspirin OD: >125mg/kg
Clinical features
- Tinnitus
- hyperventilation
- lethargy
- Nausea and vomiting
- Sweating, pyrexia
- hyperglycaemia / hypoglycaemia
- Severe: confusion, drowsiness, seizures
- Mixed respiratory alkalosis and metabolic acidosis
Management
- Oral activated charcoal if ingestion <1h
- IV sodium bicarbonate if ingestion >1h
» urinary alkalinisation increases urinary excretion of aspirin
- Haemodialysis (severe or serum concentratio >700 mg/L)
List indications for N-acetylcysteine in paracetamol overdose
give activated charcoal if ingestion within 1h of >150mg/kg paracetamol
N-acetylcysteine stimulates glutathione biosynthesis and binds toxic metabolites
- plasma paracetamol concentration: on or above a single treatment line
- staggered overdose* or doubt over the time of paracetamol ingestion or
patients who present 8-24 hours after ingestion of an acute overdose of more than 150 mg/kg of paracetamol even if the plasma-paracetamol concentration is not yet available - patients who present > 24 hours if they are clearly jaundiced or have hepatic tenderness, ALT is above upper limit of normal
if presentation >24h acetylcysteine should be continued if the paracetamol concentration or ALT remains elevated whilst seeking specialist advice
describe the management of caustic ingestion e.g. bleach
- high dose IV PPI
- symptomatic ingestion e.g. drooling, vomiting, dysphagia, odynophagia, chest pain
> urgent assessment with upper GI endoscopy - urgent upper GI surgical referral if signs of perforation
- don’t neutralise with milk due to damage from exothermic reaction
- asymptomatic ingestion can usually be discharged after a trial of oral fluid and period of observation
list complications of ingestion of caustic substances
acute
- upper GI ulceration, perforation
- upper airway injury and compromise
- aspiration pneumonitis
- infection
- electrolyte disturbance e.g. hypocalcaemia in hydrofluoric acid ingestion
chronic
- strictures, fistulae, gastric outlet obstruction
- upper GI carcinoma
describe LSD intoxication
psychoactive symptoms
- colourful visual hallucinations
- depersonalisation
- psychosis
- paranoia
somatic symptoms
- nausea
- headache
- dry mouth
- drowsiness
- tremors
signs
- tachycardia, hypertension
- mydriasis
- paraesthesia
- hyperreflexia
- pyrexia
management
- benzodiazepines
- antipsychotics if psychosis
explain the choice of location for chest drain insertion
triangle of safety
- anterior border: lateral border of pec major
- posterior border: mid-axillary line
- inferior border: nipple
usually level of 6th-8th ribs
as neurovascular bundle runs along inferior surface of ribs, aim inferiorly to avoid it
describe the management of upper GI bleeds
- resuscitation
> insert 2x wide bore cannulas in ACF
> IV fluids 0.9% NaCl
> stop anticoagulants & NSAIDs - send group + save & cross-match 2 units
> blood transfusion if Hb <70 - if oesophageal varices: terlipressin, broad-spectrum antibiotics
upper GI bleed is classified during endoscopy - proximal to ligament of Treitz
- endoscopic haemostasis
> thermal coagulation
> mechanical clipping
> adrenaline injection
> variceal band ligation
if ongoing acute bleeding despite repeated endoscopic therapy: surgery
> oversewing of ulcer
PO or IV PPI after endoscopy
Describe the adult tachycardia resus council guidelines
If adverse signs are present, up to 3 synchronised DC cardioversion shocks after which expert help should be sought
> synchronisation to R wave
adverse signs
- shock: hypotension, pallor, sweating, cold, clammy
- severe heart failure
- myocardial ischaemia
- syncope
If broad complex tachycardia (QRS>120ms)
> regular: assume VT unless previously confirmed SVT with BBB, treat with loading dose of amiodarone (300mg IV over 10-60mins) followed by 24h infusion
verapamil is contraindicated
> irregular
> most commonly AF with BBB, treat as for irregular narrow complex tachycardia
> could be AF with pre-excitation of ventricles
could be polymorphic VT (Torsades de Pointes), treat with magnesium 2g over 10 mins
If narrow complex tachycardia (QRS <120ms)
- regular
> assume SVT, attempt vagal manoeuvres
> if unsuccessful 6mg adenosine via wide bore cannula, then 12mg, then 18mg
> if unsuccessful consider atrial flutter and attempt rate control with beta-blocker
- irregular
> assume AF, if onset <48h attempt chemical or electrical cardioversion
> flecainide or amiodarone if no evidence of structural heart disease
> amiodarone if structural heart disease
> > if onset >48h anticoagulation should be given for at least 3 weeks prior to cardioversion. attempt rate control with beta-blocker.
consider digoxin or amiodarone if evidence of HF
list causes of torsades de pointes
- hypothermia
- hypokalaemia
- hypocalcaemia
- hypomagnesaemia
describe the types of pneumothorax
Accumulation of air in pleural space, resulting in the partial or complete collapse of the affected lung
Classification
- spontaneous pneumothorax
> primary spontaneous pneumothorax: without underlying lung disease, often in tall, thin, young individuals; associated with the rupture of subpleural blebs or bullae
> secondary spontaneous pneumothorax: pre-existing lung disease e.g. COPD, asthma; connective tissue diseases e.g. Marfan’s syndrome
- traumatic pneumothorax: penetrating / blunt chest trauma
- iatrogenic pneumothorax: complication of medical procedures e.g. thoracentesis, central venous catheter placement, ventilation
Tension pneumothorax: severe pneumothorax resulting in the displacement of mediastinal structures; results in severe respiratory distress and haemodynamic collapse
Catamenial pneumothorax: spontaneous pneumothorax occurring menstruating women. Caused by endometriosis within the thorax.
describe the clinical features in pneumothorax
Clinical features:
- sudden dyspnoea
- pleuritic chest pain
Signs:
- hyper-resonant percussion
- reduced breath sounds
- reduced lung expansion,
- tachypnoea
- tachycardia
> In tension pneumothorax: respiratory distress, tracheal deviation away from the side of the pneumothorax, hypotension
Describe the management of pneumothorax
rim of air is < 2cm and patient not short of breath: discharge and outpatient review in 2 days
rim of air >2cm or patient symptomatic
> aspiration: 2nd intercostal space midclavicular line
> if this fails (> 2 cm or still short of breath) insert chest drain
high-risk features require a chest drain
high risk features
- haemodynamic compromise (suggesting tension pneumothorax)
- significant hypoxia
- bilateral pneumothorax
- underlying lung disease
- >= 50 yo with significant smoking history
- haemothorax
If persistent air leak / recurrent pneumothorax: refer for VATS to allow mechanical/chemical
pleurodesis (usually talc) +/- bullectomy
Describe the management of bradycardia
Adverse features
- shock e.g. hypotension, confusion or impaired consciousness
- syncope
- myocardial ischaemia
- heart failure
Atropine (500mcg IV) is the first line treatment
If there is an unsatisfactory response the following interventions
> atropine, up to a maximum of 3mg
> transcutaneous pacing
> isoprenaline/adrenaline infusion titrated to response
Specialist help should be sought for consideration of transvenous pacing if there is no response to drugs or transcutaneous pacing
Describe ecstasy (MDMA) poisoning
Clinical features
- neuro: agitation, anxiety, confusion, ataxia
- cardiovascular: tachycardia, hypotension
- hyponatraemia due to SIADH
- hyperthermia
- rhabdomyolysis
management
- supportive
- dantrolene for hyperthermia if simple measures fail
what are the indications for thoracotomy in haemothorax?
> 1.5L blood initially or losses of >200ml per hour for >2h
Describe the management of variceal haemorrhage
- Terlipressin
- Blood transfusion if required
- Prophylactic IV antibiotics, usually quinolones
Procedures
- Endoscopic variceal band ligation
- Sengstaken-Blakemore tube if uncontrolled haemorrhage
- Transjugular Intrahepatic Portosystemic Shunt (TIPSS) if above measures fail
> can exacerbate hepatic encephalopathy
Prophylaxis: propranolol
consider rectal varices in lower GI bleeding and portal hypertension
describe hypothermia and its management
mild: 32-35 degrees
moderate/severe: <32 degrees
features
- shivering
- cold pale skin
- slurred speech
- tachypnoea, tachycardia hypertension (mild)
- respiratory depression, bradycardia, hypotension (moderate)
- confusion/impaired mental state
management
- warming with blankets
- if not responding to passive warming, use warm IV fluids or applying forced warm air directly to patient’s body
risk:
> rapid rewarming can lead to distributive shock
> cardiac arrest
> avoid IV drugs, can have drastic response
describe the clinical presentation of an upper GI bleed
clinical features
- haematemesis
- coffee ground vomit
- melaena
- haemodynamic instability
investigations
- elevated urea, low haemoglobin
- Glasgow-Blatchford score: risk for upper GI bleed
- Rockall score: post-endoscopy to estimate risk of re-bleeding and mortality
describe anaphylaxis and its management
Features
- airway compromise: swelling of the throat and tongue →hoarse voice and stridor
- Breathing problems: respiratory wheeze, dyspnoea
- Circulation problems: hypotension, tachycardia
- generalised rash, urticaria
serum tryptase levels can confirm anaphylaxis
Management
- adults: 500mcg or 0.5ml 1 in 1000 adrenaline (IM)
- 6-12 years: 300mcg or 0.3ml 1 in 1000 adrenaline (IM)
- 6 months - 6 years: 150 mcg or 0.15ml 1 in 1000 adrenaline (IM)
- <6 months: 100-150 mcg or 0.15ml 1 in 1000 adrenaline (IM)
adrenaline can be repeated every 5 mins
best site for injection - anterolateral aspect of middle third of thigh
if refractory anaphylaxis: respiratory or cardiovascular compromise despite 2 doses
management following stabilisation
> non-sedating oral antihistamine
describe ethylene glycol toxicity
aka antifreeze
features
- confusion, slurred speech, dizziness
- metabolic acidosis with high anion gap and high osmolar gap
- tachycardia, hypertension
- AKI
management
- fomepizole first-line: alcohol dehydrogenase inhibitor
- ethanol
- haemodialysis in refractory cases
describe local anaesthetic toxicity
early
- circumoral tingling and numbness, pallor, tinnitus
progresses to agitation, restlessness, twitching, excessive eye movements
late
- convulsions
- coma
- cardiac arrest (especially bupivacaine)
list criteria for CT head within 1 hour in adults
GCS <13 on initial assessment
GCS <15 at 2 hours post-injury
suspected open or depressed skull fracture
any sign of basal skull fracture (haemotympanum, panda eyes, CSF leakage from ear or nose, Battle’s sign)
post-traumatic seizure
focal neurological deficit
more than 1 episode of vomiting
describe the management of a tricyclic antidepressant overdose
e.g. amitriptyline, dosulepin
- IV bicarbonate: first-line for hypotension or arrhythmias, also widening QRS >100
- other drugs for arrhythmias (not flecainide or amiodarone)
- Intravenous lipid emulsion
- Dialysis is not effective
Describe the effects of cocaine and the management of cocaine toxicity
cocaine blocks the uptake of dopamine, noradrenaline and serotonin
Adverse effects
- cardiovascular
> coronary artery spasm → myocardial ischaemia/infarction
> both tachycardia and bradycardia may occur
> coronary artery dissection
> hypertension
> QRS widening and QT prolongation
> aortic dissection
- neurological
> seizures
> mydriasis
> hypertonia
> hyperreflexia - psychiatric effects: agitation, psychosis, hallucinations
- GI: ischaemic colitis, perforated ulcer
- hyperthermia
- metabolic acidosis
- rhabdomyolysis
Management
> benzodiazepines are first-line for most cocaine-related problems
> chest pain: benzodiazepines + glyceryl trinitrate; if myocardial infarction develops then primary percutaneous coronary intervention
> hypertension: benzodiazepines + sodium nitroprusside
describe the adult advanced life support algorithm
Adult advanced life support
> ‘shockable’ rhythms: ventricular fibrillation/pulseless ventricular tachycardia (VF/pulseless VT)
> ‘non-shockable’ rhythms: asystole/pulseless-electrical activity (asystole/PEA)
Major points include:
chest compressions
> ratio of chest compressions to ventilation is 30:2
defibrillation
> a single unsynchronised shock at 200J for VF/pulseless VT followed by 2 minutes of CPR
> if the cardiac arrested is witnessed in a monitored patient (e.g. in a coronary care unit) then up to three quick successive (stacked) shocks
> IV access should be attempted and is first-line
> adrenaline 1 mg as soon as possible for non-shockable rhythms
> > during a VF/VT cardiac arrest, adrenaline 1 mg is given once chest compressions have restarted after the third shock
repeat adrenaline 1mg every 3-5 minutes whilst ALS continues
> amiodarone 300 mg in VF/pulseless VT after 3 shocks have been administered
> a further dose of amiodarone 150 mg should be given to patients who are in VF/pulseless VT after 5 shocks have been administered
> lidocaine if no amiodarone available
thrombolytic drugs should be considered if a pulmonary embolus is suspected
> if given, CPR should be continued for an extended period of 60-90 minutes
Describe serotonin syndrome and its management
Caused by
> SSRIs (tramadol may precipitate with SSRIs)
> MAOIs
> ecstasy
> amphetamines / novel psychoactive stimulants
Onset within hours
Features
- hyperreflexia, clonus
- tremor
- tachycardia, increased BP
- Pyrexia / hyperthermia, sweating
- Rigidity
- dilated pupils
- altered mental state / confusion
diagnosis: elevated creatine kinase
Management
- IV fluids
- Benzodiazepines
- Severe cases: cryptoheptadine, chlorpromazine
describe the clinical features of opioid misuse
- rhinorrhoea
- needle track marks
- pinpoint pupils
- drowsiness
- watering eyes
- yawning
describe methaemoglobinaemia
haemoglobin which has beenoxidised from Fe2+ to Fe3+ leading to tissue hypoxia
causes
- congenital
- drugs:
> sulphonamides
> nitrates: including recreational nitrates e.g. amyl nitrite ‘poppers’
> dapsone
> sodium nitroprusside
> primaquine
- chemicals: aniline dyes
Features
- ‘chocolate’ cyanosis
- dyspnoea, anxiety, headache
- severe: acidosis, arrhythmias, seizures, coma
- normal pO2 but decreased oxygen saturation
Management
- NADH methaemoglobinaemia reductase deficiency:ascorbic acid
- IV methylthioninium chloride (methylene blue) if acquired
