This document discusses succinylcholine apnea, which is a prolonged paralysis caused by failure to metabolize the muscle relaxant succinylcholine. It is most commonly caused by low or atypical levels of the plasma cholinesterase enzyme. The document notes that atypical plasma cholinesterase is more common in those of Arya Vysya ethnicity from parts of India. It provides guidelines for identifying patients at risk of succinylcholine apnea prior to surgery using blood tests, discusses treatment options, and shares two experiences the author had with patients who experienced prolonged paralysis due to low plasma cholinesterase levels.

1. DR B Sharath Chandra Kumar
Post Graduate
MD Anaesthesiology
CHALMEDA ANAND RAO INSTITUTE OF MEDICAL SCIENCES
Karimnagar, INDIA
Guide : DR B Syama Sundara Rao, Prof

2. INTRODUCTION
 Also known as scoline apnoea or post anaesthetic
apnoea
 Abnormal prolongation of action of succinyl choline,
due to failure of the body to metabolise it; leading to
sustained paralysis

3. Succinylcholine
 Depolarizing muscle relaxant
 Rapid action, 30-60 sec
 Quick metabolism, 3-5 min
 Metabolized by plasma cholinesterase, also known as
pseudocholinesterase or butyryl cholinesterase or
BuChE

4. Causes of Succinyl-choline apnea
1. Low or atypical Plasma Cholinesterase Level
2. Altered Response of the End-Plate to Depolarizing
Relaxants; myasthenia gravis
3. Accumulation of Succinylmonocholine after a dose
of 5-7 mg/kg body weight, which is slowly
metabolized than succinylcholine
4. Central Depression From Succinylcholine
5. Failure of Redistribution of Succinylcholine from the
End-Plate
6. Hepatic failure, pregnancy

5. Atypical pseudo cholineterase
 Naturally occurring mutation Leu307Pro of human
butyrylcholinesterase
 Produces Atypical pseudo cholineterase
 Wont metabolize succinylcholine
 Succinylcholine apnoea

6. Atypical pseudo cholineterase and
vysyas
 Incidence of Atypical pseudo cholineterase was found
more in arya vysya community
 Arya vaishya or arya vysya is an orthodox telugu/
kannada speaking indians
 Found in Andhra Pradesh, Karnataka, Tamil Nadu,
Maharashtra and Orissa

7. Notable people from arya vysya
MAHATMA GANDHI – our father of nation
POTTI SREERAMULU – sacrifised life for
formation of our state andhra pradesh
KONIJETI ROSAIAH – ex CM of AP
& present governor of tamilnadu

8. How to identify pre operatively?
1. Simple blood test using ACHOLEST Test Paper :
- When a drop of the patient's plasma is applied to
the substrate-impregnated test paper, a colorimetric
reaction occurs. The time it takes the exposed
Acholest Test Paper to turn from green to yellow is
inversely proportional to the pseudocholinesterase
enzyme activity in the plasma sample

9. ACHOLEST TEST PAPER INFERENCE
Reaction time in minutes Pseudocholinesterase activity
< 5 above normal
5 - 20 normal
20 - 30 borderline low
> 30 below normal

10. 2. Dibucaine number :
- an amide local anaesthetic
- inhibits normal pseudocholinesrerase by 80 %
& atypical one with only approx 20 %
- Dibucaine number 80 indicates normal
enzyme, homozygous atypical variant has Dibucaine
number 20

12. Prevention
 Good history regarding vysya status & previous
prolongation
 Estimation of pseudocholinesterase Qualitatively &
Quantatively
 Rule out other systemic diseases like hepatic
dysfunction
 Avoid repeated & large doses of succinylcholine

13. Treatment
1. Fresh Plasma transfusion from non deficient person
2. Continue controlled ventilation till full recovery
3. Recombinant pseudocholinesterase administrarion
4. Not much role of anti cholinesterases

14. My experiences
1. A 20 year old engineering student posted for an ENT
surgery.
- PAC done. ASA grade 1, VYSYA, MPG 2
- on the day of surgery, junior resident failed to inform
that he is a vysya
- as usual we gave propofol & succinylcholine
- patient did’nt recover even after 15 min
- to our horror, we came to know that he was a vysya
- that patient recovered 6 hours after elective
ventilation
- a great relief to whole of our department

15. 2. a 35 year male patient posted for upper limb ortho
surgery
- PAC done on the day before
- ASA 1, MPG 1, VYSYA
- brachial plexus block was given through inter
scalene approach using winnie technique
- surgery started & patient was in discomfort due to
sparing
- immediately converted to GA using propofol &
scoline
- again same horror
- but to our goodness he recovered in 45 min. all of
us had a sigh….

16. Bibilography
1. Bush, G. H., Prolonged apnea due to suxamethonium.
Brit..1. Anae8th. 33,454(1961).
2. Harris, H., Whittaker, M., Lehmann, H., and Silk, E.,
The pseudocholinesterase variants. Esterase levels and
dibucaine numbers in families selected through
suxamethonium sensitive individuals. Acta Genet.
Statist. Med. 10, 1 (1960).
3. Stoelting physio pharma
4. Millers

17. Thanks