So why does Life Bubble not let you breath freely when it is right in the spell description as its own distinct sentence?
From Life Bubble
You surround the touched creatures with a constant and moveable 1-inch shell of tolerable living conditions. This shell enables the subjects to breathe freely, even underwater or in a vacuum, as well as making them immune to harmful gases and vapors, including inhaled diseases and poisons and spells like cloudkill and stinking cloud.In addition, the shell protects subjects from extremes of temperature (per endure elements) as well as extremes of pressure.
Life bubble does not provide protection from negative or positive energy (such as found on the Negative and Positive Energy planes), the ability to see in conditions of poor visibility (such as in smoke or fog), nor the ability to move or act normally in conditions that impede movement (such as underwater).
It seems like the original question about chokehold and cave-ins is covered in the second paragraph that says Life bubble does not provide protection from ... conditions that impede movement.