There are three states you can be in:
Recovering: The patient heals damage through extended rest. See Recovering from damage.
Stable: The patient takes one point of damage each day.
Dying: The patient must make a death save at the start of each of their initiative or die.
If after taking damage you are Mortally wounded, that is your Wound State is Mortal, you start Dying.
The first aid skill and what you can do with it
The first aid skill represents the ability to keep someone alive despite physical trauma. It does not cover advanced medical procedures. Low levels of the first aid skill are the equivalent of having taken a few courses. Mid-levels of the first aid skill are the equivalent of paramedic training. High levels of the first aid skill are the equivalent of advanced training in field surgery.
The most common use of the first aid skill is to keep wounded comrades from dying. To stabilize a comrade TECH+First Aid is rolled against the total damage suffered by the patient. If the action is successful the patient is stable and does not need to roll death saves for the next d6 * 10 minutes. After this “Golden Hour” the comrade needs to make a death save every 10 minutes. It is advisable to get actual Medical treatment before this time is up. See the Medical skill to know how that works.
If a patient is stabilized multiple times (for example because they have taken damage) roll the length of the Golden Hour each time the patient is stabilized, but apply only the shortest time.
The medical skill and what you can do with it
The medical skill represents in depth knowledge of the human body and various medical procedures. Low levels of medical skill are common amongst nurses and medical school drop outs. Mid-levels of medical skill are common amongst doctors and surgeons. High-levels of medical skill are common amongst famous surgeons whose time you can not afford.
The most common application of the medical skill is to save the mortally wounded. The patient should be stabilized before beginning the procedure since it is likely to take a while. Stable patients do not need to make death saves during this kind of operation. Make a TECH+Medical skill roll against the total damage suffered by the patient. If successful, the patient begins Recovering and no longer needs to make death saves. If unsuccessful the patient must make a death save. If the patient passed the death save the procedure can be attempted again. If the patient died see below about reviving them.
Another common application of the medical skill is to revive a mortally wounded patient from clinical death. Make a TECH+Medical skill roll against the total damage suffered by the patient. If successful, the patient is stable and alive. If the roll fails, the patient is stable but dead. Once the patient has failed a death save roll the medical skill gives you one shot at bringing them back. If you don’t have the medical skill it might be a good idea to let someone more competent take that shot.
The medical skill is also used for surgical operations, such as those required by people who have taken damage to their Vitals or who wish to install cybernetics. The difficulty depends on the operation in question, see Surgery.
Finally the medical skill is also used for the things you go to the doctor for, such as getting your cancer diagnosed and treated. Yeah, right, I’m sure its the cancer that will get Johny Solo.
Note that the medical skill can not be used to stabilize a patient, only to stop the death saves or to revive them should they die.
Recovering from damage
There is no such thing as a potion of healing. The only way to get rid of damage is to rest until your body heals itself. In order to ensure this process does not go wrong you need either the medical skill or, if you are not mortally wounded, the first aid skill.
If the patient is already recovering and does not exert him or herself no skill roll is needed: the care taker simply checks that everything is okay. If they used the medical skill the patient heals one point of damage every day, if the first aid skill was used they heal one point for every two days of rest.
If the patient does exert him or herself she slips from Recovering to Stable and requires attention. Roll INT+Medical or INT+First Aid (if not mortally wounded) against the total damage remaining. If successful the patient is once again recovering and will get better. If unsuccessful the patient takes the point of damage from being stable. If the patient is mortally wounded by this, he or she is now dying, exactly as if she had taken that damage from any other source.
Certain drugs and biomods give a bonus to healing rate. Unless the drug or mod states otherwise this extra healing is on top of normal healing, but does not occur if the character is getting worse. So if Johny Solo is recovering in a hospital (treated with the medical skill) with a Speed Heal™ (+1 to healing) treatment he recovers two points of damage every day. If Johny Solo were to leave the hospital and exert himself without seeking further medical aid he would take one point of damage per day and the speed heal would not do anything to help.