Effects of normothermic organ bath and verapamil–nitroglycerin solution alone or in combination on the blood flow of radial artery

Objective: Radial artery pedicle tissue cooling during harvesting is one of the major causes of vasospasm. We aimed to compare the effects of the pedicle rewarming method, normothermic organ bath, and one of the most preferred topical antispasmodic agents, verapamil–nitroglycerin solution alone or in combination on the blood flow of radial artery. Methods: Consecutively randomized patients (n = 80) undergoing coronary bypass were organized as four equal-sized groups. Effects of normothermic organ bath and topically performed verapamil–nitroglycerin solution alone or in combination on the blood flow of radial artery were investigated. In the control group no antispasmodic treatment was performed. Free flows were measured at three stages: as initial flow after minimal distal harvesting, post-harvesting flow after total harvesting, and post-treatment flow following a waiting period after the application of the antispasmodic protocol. At each stage, pedicle and esophageal temperatures were also recorded. Results: Radial artery pedicle temperatures decreased significantly during harvesting in all groups (p ≪ 0.001). Normothermic organ bath, topical verapamil–nitroglycerin solution treatment, and their combination increased flow significantly (p ≪ 0.001, from 40.3 ± 10.48 ml/min to 64.3 ± 18.8 ml/min, from 38.9 ± 13.91 ml/min to 62.75 ± 15.23 ml/min, from 41.4 ± 11.19 ml/min to 75.4 ± 15.32ml/min, respectively). The differences between the initial and post-treatment flows were not significant in the combined procedure group (p > 0.05), whereas the initial levels were not reached in the post-treatment flows (p ≪ 0.05) in the normothermic organ bath and verapamil–nitroglycerin groups. Conclusions: Hypothermia plays an important role in radial artery vasospasm. Normothermic organ bath and verapamil–nitroglycerin solution alone or in combination relieve spasm of radial artery.