How was it physically possible for Tsunade to survive being bisected?

[Joshutsu]

She most likely stopped the bleeding before she first passed out. Then she summoned katsuya to help fix her and the kage up.

That would have been a good point in the story for her to die. But we need new village elders so i guess it's a good thing she's still alive.

 

[The Paradox]

She's Senju/Uzumaki. She has healing abilities on cellular level. She has superb chakra control. The beam that she's under is also slowing down the process of her bleeding out, buying her time. I'm pretty sure all of that together is what bought her enough time to survive that and heal. Any of those factors taken out and she would have died. Senju/Uzumaki have strong bodies/lifeforce thanks to being decedents of Asura. Her cellular level healing allows her to heal herself by regeneration of lost/damaged organs, nerves, possibly even chakra channels..etc. Her chakra control allows her to direct chakra to the areas in need of the most protection and healing, probably closing off areas of heavy bleeding and whatever she can't close off is being closed off by the beam. She isn't defying logic, she's just very lucky she has all of these things that are able to be used together to save her.

 

[Livenojutsu]

Because she is the fifth hokage.

 

[FemmeFatale]

She's Senju/Uzumaki. She has healing abilities on cellular level. She has superb chakra control. The beam that she's under is also slowing down the process of her bleeding out, buying her time. I'm pretty sure all of that together is what bought her enough time to survive that and heal. Any of those factors taken out and she would have died. Senju/Uzumaki have strong bodies/lifeforce thanks to being decedents of Asura. Her cellular level healing allows her to heal herself by regeneration of lost/damaged organs, nerves, possibly even chakra channels..etc. Her chakra control allows her to direct chakra to the areas in need of the most protection and healing, probably closing off areas of heavy bleeding and whatever she can't close off is being closed off by the beam. She isn't defying logic, she's just very lucky she has all of these things that are able to be used together to save her.

I think people give her lineage too much credit, it's all her . Sakura would be able to do the same thing , actually in Sakuras fight with sasori she stated that her strength comes from her will like tsuandes