[Happy birthday succinylcholine!]

Phenotype and genotype characteristics of 58 patients showing a prolonged effect of succinylcholine: A four-year experience

INTRODUCTION

This study sought to describe the phenotype and genotype characteristics of patients referred to our laboratory to undergo further assessment due to a suspicion of a prolonged effect of suxamethonium attributed to BChE deficiency.

METHODS

All patients referred to our laboratory from January 2016 to December 2019 due to the suspicion of a prolonged effect of suxamethonium were included in this study. The determination of BChE activity and genotyping using complete nucleotide sequencing of the entire complementary DNA-coding region with flanking intron-exon boundaries were completed.

RESULTS

During this four-year period, 58 patients were referred to our laboratory for the investigation of prolonged neuromuscular block due to BChE deficiency. Among them, 52 showed a BChE deficiency related to BCHE gene mutations. The most commonly detected genotype was compound homozygous atypical variant (p.Asp98Gly)/homozygous Kalow variant (p.Ala569Thr) (p.[Asp98Gly;Ala567Thr];[p.Asp98Gly;Ala567Thr]). Further, we recorded four new BCHE variants, which seem to be associated with prolonged post suxamethonium apnoea: p.(Trp205Cys), p.(Leu222His), p.(Glu469Gln), and p.(Lys276Ter).

CONCLUSION

During a four-year period, among the 58 patients referred to our laboratory, we have found four new BCHE variants, which seem to be associated with prolonged post suxamethonium apnoea (p.(Trp205Cys), p.(Leu22His), p.(Glu469Gln), and p.(Lys276Ter)).

[Storing succinylcholine in prehospital settings following the recommendations of the French National Agency for the safety of medicines]

OBJECTIVE

The French National Pharmaceuticals Agency (ANSM) has recommanded in July 2012 not to break the cold chain before using succinylcholine (Celocurine®).

RESEARCH OBJECTIVE

to understand the pre-clinical evolution of the conservation modes of this curare.

RESEARCH TYPE

Descriptive study before (year 2011) and after (year 2012).

PATIENTS AND METHOD

Online survey to French Samu/Smur.

DATA COLLECTED

SMUR location, conservation method at clinical base, in the mobile unit (UMH) and at the patient. Principal decision criteria: evolution of the conservation modes before and after the recommendation (qualitatives variables compared with a Fisher test).

RESULTS

Out of 101 SAMU/SMUR, 62 answered. Conservation modes of succinylcholine vials were significantly different (P<0.001). Proper conservation was observed in 26 % of the cases before and 43 % after. Mobile units (UMH) equipped with a fridge increased from one out of two to 77 %. The lack of conservation modes passive or active on UMH went from 31 % to 3.4 % with isotherms bags with ice when a fridge was not available. The destruction of capsules at current temperature in a 24-hour period increased: 22 % before, 47 % after (P=0.04).

CONCLUSION

After recommendations from ANSM, conservation modes and destruction of succinylcholine in a prehospital environment were significantly impacted.