Succynyl choline apnoea

1. Succinyl-choline apnea DrR B Sharath C handra K umar 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 Low or atypical Plasma Cholinesterase Level Altered Response of the End-Plate to Depolarizing Relaxants; myasthenia gravis Accumulation of Succinylmonocholine after a dose of 5-7 mg/kg body weight, which is slowly metabolized than succinylcholine Central Depression From Succinylcholine Failure of Redistribution of Succinylcholine from the End-Plate 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? 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

11. 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

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

13. My experiences 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

14. 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….

15. 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