When you go unconscious roll a d-100 and take the following penalty. These problems cannot be fixed by a long rest and require help from a dedicated healer like Kuda Zoniri

Source Xanathar's Lost Notes on Everything Else

roll d100 Injury
1-2 Lose an Eye. You have disadvantage on Wisdom (Perception) checks that rely on sight and on ranged attack rolls. Magic such as the regenerate spell can restore the lost eye. If you have no eyes left after sustaining this injury, you're blinded.
3-4 Lose an Arm or a Hand. You can no longer hold anything with two hands, and you can hold only a single object at a time.
5-6 Lose a Foot or Leg. Your walking speed is halved and you must use a cane or crutch to move unless you have a peg leg or other prosthesis. You fall prone after using the Dash action. You have disadvantage on Dexterity checks made to balance.
7-8 Lose an Ear. You have disadvantage on Charisma (Persuasion) checks and Wisdom (Perception) checks that rely on hearing. You have advantage on Charisma (Intimidation) checks.
9-10 Lose Nose. You have disadvantage on Charisma (Persuasion) checks and Wisdom (Perception) checks that rely on smell. You have advantage on Charisma (Intimidation) checks.
11-15 Blurred Vision. You have disadvantage on Wisdom (Perception) checks that rely on sight and on ranged attack rolls.
16-20 Broken Arm or Hand. You can no longer hold anything with two hands, and you can hold only a single object at a time.
21-25 Broken Foot or Leg. Your walking speed is halved and you must use a cane or crutch to move. You fall prone after using the Dash action. You have disadvantage on Dexterity checks made to balance.
26-30 Ringing Ears. You have disadvantage on Wisdom (Perception) checks that rely on hearing. The injury heals if you receive magical healing. Alternatively, the injury heals after you spend three days doing nothing but resting.
31-35 Limp. Your walking speed is reduced by 5 feet. You must make a DC 10 Dexterity saving throw after using the Dash action. If you fail the save, you fall prone.
36-40 Lose a Finger. You have disadvantage on Dexterity (Sleight of Hand) checks and Dexterity checks to use fine tools (such as thieves' tools) using the hand with which you lost the finger.
41-45 Break a Finger. You have disadvantage on Dexterity (Sleight of Hand) checks and Dexterity checks to use fine tools (such as thieves' tools) using the hand with the broken finger.
46-50 Break an Item. A randomly determined nonmagical item you hold, wear, or carry on your person is broken or ruined. Roll a d10. On a roll of 1, the item broken is a weapon, on a roll of 2 the item is armor or a shield, and on a roll of 3-10 the item is any weapon that isn’t a shield or weapon.
51-55 Teeth Knocked Out. You have disadvantage on Charisma (Persuasion) checks. When you cast a spell with a verbal component a verbal component, roll a d20, on a 1, the spell fails and the casting is lost.
56-60 Festering Wound. Your hit point maximum is reduced by 1 every 24 hours the wound persists. If your hit point maximum drops to 0, you die. The injury heals if you receive magical healing. Alternatively, someone can tend to the wound and make a DC 15 Wisdom (Medicine) check once every 24 hours. After ten success, the injury heals.
61-65 Open Wound. You lose 1 hit point every hour the wound persists. The injury heals if you receive magical healing. Alternatively, someone can tend to the wound and make a DC 15 Wisdom (Medicine) check once every hour. After ten success, the injury heals.
66-70 Skull Fracture. Whenever you attempt an action in combat, you must make a DC 20 Constitution saving throw. On a failed save, you lose your action and can't use reactions until the start of your next turn.
71-75 Punctured Lung. You can take either an action or a bonus action or your turn, but not both. The injury heals if you receive magical healing. If you puncture both lungs your hit points drop to 0 and you immediately begin dying.
76-80 Internal Injury. Whenever you attempt an action in combat, you must make a DC 15 Constitution saving throw. On a failed save, you lose your action and can't use reactions until the start of your next turn.
81-85 Broken Rib. This has the same effect as Internal Injury above, except that the save DC is 10.
86-90 Horrible Scar. You have disadvantage on Charisma (Persuasion) checks and advantage on Charisma (Intimidation) checks.
91-95 Painful Scar. You have a scar which gets painful whenever it rains, sleets, hails, or snows. Whenever you attempt an action in combat and your scar is giving you pain, you must make a DC 15 Constitution saving throw. On a failed save, you lose your action and can't use reactions until the start of your next turn.
96-100 Minor Scar. The scar doesn't have any adverse effect, but chicks dig it.