8.0 Toxicology Decontamination And Elimination Methods

Front 1

What are the 4 Methods of elimination in

Toxicology?

Back 1

1. MDAC - Multi Dose Activated Charcoal
2. Urinary Alkalinisation
3. Haemodialysis and Haemofiltration
4. Charcoal haemoperfusion.

Front 2

What drugs are managed with MDAC ?

Back 2

"the ines and the ones"...

Carbamazepine ** (Most common indication)
Theophylline
Quinine

Dapsone
Phenobarbitone

* Consideration given to :

Phenytoin / Piroxicam / Aspirin / Amanita

Front 3

What 2 drugs are managed with urinary

alkalisation ?

Back 3

1. Salicylates (Aspirin) : "First Line"
2. Phenobarbitone : MDAC is first line

Front 4

What drugs / ingestions are managed with Haemodialysis ?

Back 4

"COP I'VE STUMBLED "

Carbamazepine

Osmolar Gap elevation[ Toxic alcohols ]
Potassium [ > 40 tablets 600mg KCl / >2.5 mmol/kg with WBI ]

Valproate
Salicylates
Theophylline

Uraemia-inducing drugs (nephrotoxic drugs )
Methanol / Metformin

Lithium
[ isopropanol ; Excess acid ; Barbiturates ; Diethylene glycol ]

Front 5

What are the 2 mechanisms of MDAC ?

Back 5

1. Interruption of enterohepatic circulation

of drug
2. Gastrointestinal dialysis

Front 6

In regards to Sodium Bicarbonate

administration, what are the main scenarios for its use ?

Back 6

1. Cardiotoxicity from Na+ channel blockade

eg. TCA
2. Enhancing urinary elimination eg. salicylates

3. Preventing CNS redistribution eg. Salicylates
4. Correcting Profound life-threatening

metabolic acidosis eg. Isoniazid / cyanide
5. Increasing Urinary solubility of drug
eg. Methotrexate / Rhabdomyolysis

Front 7

List the complications of sodium bicarbonate therapy .

Back 7

1. Electrolyte issue
a. hypokalaemia
b. hypocalcaemia ( precipitation )
2. High osmotic / sodium load
- volume overload
- pulmonary oedema
3. Overshoot alkalosis
4. Paradoxical intracellular / CSF acidosis.

Front 8

What Cardiotoxic sodium channel blockade

overdoses are managed with sodium

bicarbonate administration ?

Back 8

1. TCA
2. Venlafaxine
3. Propranolol
4. Antiarrhythmics

( Ia-quinine and Ic-flecainide )

Front 9

What life threatening drug-induced metabolic acidoses are managed with sodium

bicarbonate ?

Back 9

1. Toxic alcohols
2. Isoniazid
3. Cyanide

Front 10

What drugs have their urinary elimination

increased with sodium bicarbonate ?

Back 10

1. Salicylates
2. Phenobarbitone

Front 11

What toxicology emergencies are managed with sodium bicarbonate to increase the drug

solubility in the urine ?

Back 11

1. Drug-induced rhabdomyolysis
2. Methotrexate toxicity.

Front 12

Which Toxicological Emergencies are managed with Whole Bowel Irrigation (WBI) ?

Back 12

1. Metal toxicity
a. Iron overdose > 60 mg/kg
b. Lead ingestion
2. Slow Release (SR) agents
a. Potassium Chloride (KCl) > 2.5 mmol/kg
b. Life threatening SR Calcium Channel Blocker Overdose
[ Non-dihydropyridines - verapamil / diltiazem ]
3. Body packers
4. Arsenic ingestion - symptomatic

Front 13

List the contraindications for single dose

activated charcoal .

Back 13

1. Incomplete resuscitation

2. Decreased level of consciousness

3. Drug not adsorbed by charcoal

4. Risk Assessment issues:

a. Seizure potential

b. Non toxic dose ingested

Front 14

List the complications of charcoal.

Back 14

1. Vomiting 30%

2. pulmonary aspiration

3. Mess

4. Distraction of Staff

Front 15

List the drugs not adsorbed by Charcoal.

Back 15

1. Alcohols (Toxic )

2. Hydrocarbons ( eucalyptus oil)

3. Metals ( Lithium ; lead ; iron ; potassium)

4. Corrosives ( acids / alkalis)

Front 16

List the complications of Multi dose activated charcoal (MDAC).

Back 16

1. Vomiting 30%

2. Charcoal aspiration

3. Constipation

4. Charcoal bezoar formation

5. Staff distraction -resources

Front 17

List the drugs that cause Pharmacobezoars.

Back 17

1. Charcoal

2. Iron

3. Aspirin (EC)

4. TCA (clomipramine)

5. Venlafaxine

6. Theophylline

7. Calcium Channel Blockers (CCB SR)