Post on 16-Nov-2014
Sux Apnoea- A Case Study
Karenne Nielsen
Clinical Nurse Specialist
West Gippsland Healthcare Group
Suxamethonium Chloride “Sux” “Scoline”
Short acting muscle relaxant Allows rapid intubation of trachea &
provides short periods of neuromuscular
blockade Main uses - difficult intubation
- emergency conditions
- brief procedures
Suxamethonium “Sux”
Dose = 1-2 mgs/kg IVI or IMI Rapid onset of muscle relaxation
- fasciculation 30-60 seconds Short duration of 5-10 minutes
- apnoea lasts ≈ 5 mins
- paralysis recovery another 5 mins
Suxamethonium – “Sux”
Metabolised by plasma cholinesterase
- an enzyme produced in the liver & present in the blood
Plasma cholinesterase is usually present in sufficient concentration to give a half-life of approx. 4 mins
No reversal agent
Side effects
Cardiovascular – bradycardia Hyperkalaemia Raised intraocular/pressure Allergic reaction → Anaphylaxis Malignant hyperthermia Muscle pains- calf & chest Prolonged muscle paralysis
“Sux apnoea”
Rare condition in 4-6% population Patients with abnormal plasma
cholinesterase are incapable of metabolising suxamethonium resulting in prolonged muscle paralysis and apnoea.
Inherited - often normal levels but abnormal plasma cholinesterase (up to 8hrs or more)
Acquired – lower levels of normal plasma cholinesterase
Case study
55 year old Female No significant medical/family history Nil current medications Non smoker Surgical & Anaesthetic history
- Varicose Vein Ligation 2002
- GA no muscle relaxants
Pre-Anaesthetic Assessment
Weight: 77.5 kgs / Height: 156cm Reflux lying flat in bed “High risk of gastric reflux” Undershot jaw – Airway Grade III “? Difficult intubation” ASA score 2 Anxious patient ++
Anaesthetic drugs
Midazolam 2mgs IVI Fentanyl 100µgs IVI Propofol 200mgs IVI Suxamethonium 100mgs IVI @ 1355 Nitrous/Oxygen 2:2 Sevoflurane 2% Cephazolin 1gm IVI
Anaesthetic/Operation
Ventral Hernia Repair with Mesh - surgery straightforward = 1hr No muscle movement noted
throughout the operation – end time 1hr & 10 mins after “sux”given
Sux apnoea or another diagnosis ? Assumption of Sux apnoea confirmed
by nerve stimulation
Management
Anaesthesia maintained - important to be patient - keep asleep and unaware Continuous monitoring Entropy monitoring Fluid and electrolyte balance Temperature BSL
Management
Urinary catheter Pressure area care Calf stimulation Eye care Wound/drain care Nerve stimulator
Plan for emergency surgery
Management
Relatives kept informed & to visit
- truthful explanation of condition
- reassure safe & waiting to wake
- ? Fresh Frozen Plasma Started to swallow @ 6½hrs Extubated 30 mins later Total time = 7 hours
Recovery
Drowsy Co-operative and talking No recollection Required narcotic analgesia Very dry mouth Puffy eyes Husband to visit
Post-op period
Hypokalaemia post op day 1& 2
- Potassium replaced IVI & orally Febrile post op day 2
- CXR ? pneumonia
- oral antibiotics Erythema of wound day 3 Discharged post op day 5
Follow up for Sux Apnoea
Review 1 month post-op Debriefing with family present - Sux Apnoea episode - Importance of alerting staff with
future anaesthetics - Pseudocholinesterase typing & Phenotype differentiation Patient and family tested
Follow up testing
Normal Dibucaine = over 70% Homozygous normal = (6.0-15.6) “K” – Dibucaine Inhibition = 15%
confirming susceptibility to “Sux” Genotype testing unavailable but
length of apnoea suggests rare clinical variant
Children 4/6 tested – all normal levels
The end!!
Thankyou very much for your attention.