Ignore this bullshit about hitpoints: it’s all about heartrate. At higher and lower heartrates, you unlock different abilities, and manage it in and out of combat. Bards, Surgeons, and Tacticians can lower or raise your heartrate at will. You can use sedatives or stimulants to alter your heartrate as well. Each job has different minimum and maximum bands for heartrate, and you don’t want to dip above or below.
You can see your teammates’ heartrate at any time even if you’re not in the same room; the Merry Band has magic items called Pearl Mirrors which lets you communicate with your crew even when you’re not in natural earshot, and also lets you see their status.