Reaction time in minutes Pseudocholinesterase activity

< 5 above normal

5 - 20 normal

20 - 30 borderline low

> 30 below normal

105

Drugs - Benzodiazepine premedication

- Opioid overdose intra-operatively

- Insufficient reversal of nondepolarising muscle relaxants

- Suxamethonium

- Failure to discontinue anaesthetic vapour

-Pre-operative alcohol intoxicationEndocrine - Severe hypothyroidism

- Hypoglycaemia

- Diabetic keto-acidosis (DKA), hyper osmotic nonketotic coma (HONK)

- Addison’s crisisElectrolyte disturbances

- Hyponatraemia

- Hypocalcaemia

- Hypermagnesaemia (magnesium sulphate treatment etc)

Acid-base disturbances

- Hypercapnoea (“Carbon dioxide narcosis”) – due to hypoventilation

- Hypocapnoea (no drive for breathing) – due to hyperventilation

Hypothermia

Intra-operative complications - Cerebro-vascular incident

- Myocardial infarctionUndiagnosed muscle diseases

Treat apnoea - Mechanical ventilation until normal muscle strength returns- peripheral nerve stimulator to distinguish between central

depression and neuromuscular block Prevent awareness - Continue anaesthesia with inhalant or sedate well with

benzodiazepines

Exclude differential diagnosis

- Drugs, Endocrine, Electrolyte disturbances, Acid-base disturbances,Hypothermia, Intra-operative complications, Undiagnosed muscle diseases

Fresh frozen plasma/whole blood

- Contains Pseudo-cholinesterase will speed recovery

Recombinant Pseudo-cholinesterase

- Very expensive. # Cheaper to treat symptomatically

Confirm scoline apnoea - Pseudo-cholinesterase activity- dibucaine or fluoride number

If scoline apnoea confirmed - Council patient family members- Medic alert bracelet for patient- Test family members