"Deterioration Of The Fight Or Flight Responce" is the twenty-sixth episode of the second season of Grey's Anatomy and the 35th produced episode of the series. It is also the 35th produced episode of the Grey's Anatomy franchise. It was broadcast on May 15, 2006.
After cutting Denny’s LVAD wire in her bid to make sure he gets the heart, Izzie places her surgical career on the line while George, Cristina and Meredith all find themselves trying to help her save Denny’s life while Bailey goes on the offensive when she discovers the truth about the situation. Derek wrestles with the life of one of his friends and colleagues being in his hands after Burke’s shooting and Cristina struggles with standing by her man during his time of need while Richard’s family life faces a challenge when Adele arrives at the hospital with his niece.
- "Human beings need a lot of things to feel alive. Family. Love. Sex. But we only need one thing to actually be alive. We need a beating heart. When our heart is threatened we respond in one of two ways. We either run or we attack. There's a scientific term for this: fight or flight. It's instinct, we can't control it. Or can we?"
- "Universe & U" - KT Tunstall
- "Look At Her Face" - The Coral Sea
- "Through The Backyards" - Au Reviour Simone
- "How We Operate" - Gomez
This episodes' title references the album Deterioration Of The Fight Or Flight Responce, originally sung by The Flaming Lips