Toxicities/OD/poisoning

Question 1

Fts of digoxin toxicity

Answer 1

• generally unwell, lethargy
• nausea and vomiting, anorexia
• confusion,
• yellow-green vision
• arrythmias (AV block, bradycardia)
• gynaecomastia

Question 2

Precipitating factors to digoxin toxicity

Answer 2

• classically hypokalaemia (less K = more digoxin binding to cardiac muscle ATPase pump = incr inhibitor effects
• renal failure
• MI
• hypo-mg/ca/na/albumin
• hypothermia
• hypothyroid
• acidosis
• drugs: amiodarone, quinidine, verapamil, diltiazem, spironolactone + hypokalamia causing drugs (thiazides, loop diuretics)

Question 3

Management of digoxin toxicity

Answer 3

• digibind
• correct arrhythmia
• monitor potassium

Question 4

Diagnosing digoxin toxicity

Answer 4

• not levels alone (can be normal) – but likely if levels incr from 1.5 to 3
• levels taken 8-12hrs from last dose
• clinical fts

Question 5

Mx of paracetamol OD

Answer 5

• <1hr = charcoal
• N-acetylcysteine infusion (NAC)
• last line: liver transplant

Question 6

Salicylate OD management

Answer 6

(AKA aspirin)

urine alkalinazation with IV bicarbonate
haemodialysis

Question 7

Opioid OD Mx

Answer 7

naloxone

Question 8

Benzodiazepine OD management

Answer 8

• mostly supportive
• flumenazil if severe/iatrogenic OD (high risk of seizures)

Question 9

TCA OD Mx

Answer 9

• IV bicarbonate = may reduce risk of seizures/arrhythmias in severe toxicity
• NOT quinidine/felcainide or amiodarone if arrythmias (prolong depolarization/QT); sometimes lignocaine; mainly correct acidosis
• dialysis is NOT effective

Question 10

Lithium OD Mx

Answer 10

• mild-mod: volume resus with N.saline
• severe: haemodialysis
• sodium bicarb potentially promotes lithium excretion by incr alkalinity of urine, but limited evidence

Question 11

Warfarin toxicity Mx

Answer 11

• vitamin K
• prothrombin complex

Question 12

Heparin OD

Answer 12

Protamine sulphate

Question 13

Beta-blocker OD Mx

Answer 13

• if bradycardic = atropine
• if resistant= consider glucagon

Question 14

ethylene glycos poisoning (anti-freeze)

Answer 14

• first line: fomepizole
• refractory: haemodialysis
• in the past = ethanol was used (competes with enzyme = limits formation of toxic metabolites)

Question 15

Methanol poisoning Mx (industrial solvent/pesticide/fuel)

Answer 15

• fomepizole or ethanol
• haemodialysis

Question 16

Iron poisoning Mx

Answer 16

desferrioxamine (chelating agent)

Question 17

Lead poisoning Mx

Answer 17

dimercaprol
calcium edetate

Question 18

Carbon monoxide poisoning mx

Answer 18

• 100% oxygen
• hyperbaric oxygen

Question 19

Cyanide poisoning mx

Answer 19

• hydroxocobalamin
• or combo of amyl nitrite, sodium nitrite and sodium thiosulfate