Plasma cholinesterase variants in a Saudi population presenting for surgery

ABSTRACT

The frequencies of abnormal plasma cholinesterase activities and genotypes were evaluated in 977 Saudi surgical patients and 943 [96.5%] were found to have the normal phenotype. Seventy-six patients [8%] had decreased enzyme activity and 34 [3.5%] had different abnormal genotypes. The most common abnormal genotype was the heterozygous occurrence of the usual and the atypical gene [E[u]E[a]], which was found in 23 patients [2.4%]. On the whole, the distribution of phenotypes was similar to that found in most other Caucasian populations. However, there were some indications of an unusually high frequency of the silent allele It is concluded, that of the total of 977 patients investigated, 27 patients [i.e. 2.8%] would have shown an abnormal response had they been given succinylcholine. However, the duration of respiratory insufficiency following a normal intubation dose of succinylcholine [1 mg/kg] would have exceeded 1 h in less than 1% of the patients