The time to act is now: a call to action on planetary health and sustainable surgical systems. Issue 12 (December 2022) - Zaigham, Mehreen; Bryce-Alberti, Mayte; Calderon, Chrystal; Campos, Letícia Nunes; Raguveer, Vanitha; Nuss, Sarah; Dutta, Rohini; Naus, Abbie E; Forbes, Callum; Park, Kee B; McClain, Craig D