Life Jay Leno is undergoing ‘very aggressive’ hyperbaric oxygen therapy. Five things to know about it. November 18, 2022 Natalie Neysa Alund, USA TODAY Comments Off on Jay Leno is undergoing ‘very aggressive’ hyperbaric oxygen therapy. Five things to know about it. After excision and grafting surgery for second and third-degree burns, comedian Jay Leno is undergoing aggressive hyperbaric oxygen therapy.