RESUMO
We investigated whether genetic variations of the beta-2 adrenergic receptor (ADRB2) modulate the haemodynamic response following spinal anaesthesia for caesarean delivery. We focused on the effects of haplotypes formed by combinations of the Arg16Gly and Gln27Glu polymorphisms. Clinical data from 143 healthy parturients were collected. Only the ArgGln haplotype appeared to influence the risk of hypotension, most probably through a recessive mode of inheritance (p=0.027). Therefore, patients were grouped according to ArgGln homozygosity in two groups: presence of one or no copies of the haplotype (n=120) or two copies of the haplotype (n=23). Both groups presented similar baseline characteristics. Comparatively, patients homozygous for the ArgGln haplotype presented consistently higher blood pressure levels throughout the evaluation period (p=0.001 for systolic arterial pressure variation from baseline). In conclusion, our results demonstrate that haplotype variations of the the ADRB2 modulate the haemodynamic response following spinal anaesthesia for caesarean delivery.
