Schroeder, D. R.

β 2 ‐adrenergic receptor (ADRB2) gene polymorphisms influence vasodilation, but studies investigating regional or systemic responses conflict, possibly due to counter‐regulatory baroreflex action during systemic β 2 ‐agonist infusion. We tested the hypothesis that ADRB2 gene variation would influence the SVR response to ADRB2 agonist terbutaline (TERB) during baroreflex inhibition. 40 healthy young adults were recruited according to the double homozygous haplotypes: Arg16+Gln27 (n=13), Gly16+Gln27 (n=6), and Gly16+Glu27 (n=21). Arterial pressure was measured by brachial arterial catheter, cardiac output by acetylene breathing. Lymphocytes were sampled for ex vivo analysis of ADRB2 density and binding conformation. Following baroreflex ablation with trimethaphan (3–7 mg/min), phenylephrine was titrated to restore blood pressure to baseline. TERB was infused i.v. at 33 and 67 ng/kg/min for 15 min/dose. There was partial evidence to suggest a main effect of haplotype on the change in SVR ( P = 0.06). For SNP position 16, the highest dose of TERB produced lower SVR in Gly16 vs Arg16 ( P = 0.03). Lymphocyte ADRB2 binding conformation was similar but receptor density was greater in Gly16 vs Arg16 ( P = 0.05). During baroreflex inhibition, the SVR response to systemic ADRB2 agonist is suggestive of augmented ADRB2 function in Gly16+Glu27 homozygotes, with greater influence from Gly16. Supported from NIH and DFG.

Background: Nondepolarizing neuromuscular blockade is reversed with neostigmine/glycopyrrolate or sugammadex. Anticholinergic glycopyrrolate decreases bladder detrusor muscle contractility, potentially leading to postoperative urinary retention (POUR). POUR commonly complicates inguinal herniorrhaphy. In this study we assess association between reversal technique and POUR. Methods: Records of adult patients undergoing unilateral inguinal herniorrhaphy with neuromuscular blockade from January 2013 to September 2020 were reviewed for POUR (unplanned postoperative insertion of urinary catheter). A propensity-adjusted analysis was performed to assess POUR in neostigmine/glycopyrrolate versus sugammadex using inverse probability of treatment weighting (IPTW) to adjust for potential confounding. Results: We identified 181 patients who underwent herniorrhaphy with amnio-steroidal neuromuscular blockers, 75 (41.4%) who received sugammadex and 106 (58.6%) neostigmine/glycopyrrolate. Compared with sugammadex, neostigmine/glycopyrrolate group had longer surgical course [unweighted standardized difference (USTD)=0.38, P=0.004], received more intraoperative opioids (USTD=0.704, P<0.001), more often performed via laparoscopic approach (USTD=0.407, P=0.012), and less often with periprocedural urinary catheter insertion (USTD=0.452, P=0.003). POUR was observed in 2 (3%) of patients in the sugammadex group, and 16 (15%) in neostigmine/glycopyrrolate [unadjusted odds ratio (OR)=0.15; 95% confidence interval (CI): 0.03-0.69; P=0.015, and IPTW OR=0.13; 95% CI: 0.03-0.64; P=0.012]. Results remained similar with further analysis adjusted for opioid administration in the postanesthesia care unit (adjusted IPTW OR=0.18; 95% CI: 0.04-0.88; P=0.034). Of the POUR patients, 9 required unplanned overnight admission and 4 emergency room visit. Conclusion: These results suggest that neuromuscular blockade reversal with sugammadex is associated with lower rates of POUR following unilateral inguinal herniorrhaphy. Our results need to be reconfirmed in a randomized prospective study.