A joint US-Brazilian study has shown coffee hinders the performance of new vitreoretinal (VR) surgeons, while beta blockers may improve it.

Published in Jama Ophthamology, the single-blind, cross-sectional study assessed the effects of caffeine alone, a β-blocker (propranolol) alone or a β-blocker and caffeine combination on the surgical performance of 15 VR surgeons with less than two years surgical experience.

Propranolol alone was associated with improved surgical performance compared with caffeine alone and the combination of caffeine and propranolol, suggesting caffeine negatively affects surgical performance. “These results may be helpful for novice vitreoretinal surgeons to improve microsurgical performance,” said the authors.