Bleeding (aka hemorrhaging) is blood escaping from the circulatory system.

• Traumatic injury, including:
  • Abrasion
  • Excoriation
  • Hematoma
  • Laceration
  • Incision
  • Puncture wound
  • Contusion
  • Crushing injuries
  • Ballistic trauma
• Underlying medical condition
• Combination

• By degree of blood loss, including:
  • Class 1 hemorrhage, which involves loss of <15% blood volume
  • Class 2 hemorrhage, which involves loss of <30% blood volume
  • Class 3 hemorrhage, which involves <40% blood volume
  • Class 4 hemorrhage, which involves >40% blood volume
• By depth, including:
  • Internally, where blood leaks from blood vessels inside the body
  • Externally, through a natural opening (e.g. mouth, nose, ear, urethra, vagina, anus), or through a break in the skin
• By origin of bleeding, including:
  • Mouth:
    • Hematemesis (vomiting fresh blood)
    • Hemoptysis (coughing up blood from the lungs)
  • Anus:
    • Hematochezia (rectal blood)
  • Urinary tract:
    • Hematuria (blood in urine from urinary bleeding)
  • Upper head:
    • Intracranial hemorrhage (bleeding in the skull)
    • Cerebral hemorrhage (type of ICH, bleeding wihtin the brain itself)
    • Intracerebral hemorrhage (bleeding in the brain caused by rupture of a blood vessel within the head)
    • SAH (presence of blood within the subarachnoid space, usually due to rupture of a berry aneurysm or an AVM)
  • Lungs:
    • Pulmonary hemorrhage
  • Gynecologic:
    • Vaginal bleeding, including PPH, breakthrough bleeding
    • Ovarian bleeding, a potentially catastrophic and not so rare complication among lean Pt's w/ PCOS undergoing transvaginal oocyte retrieval
  • GI:
    • Upper GI bleed
    • Lower GI bleed
    • Occult GI bleed

• Hemostasis, which is stopping or controlling bleeding, is apart of first aid and surgery

• Hypovolemia is massive decrease in blood volume
• Exsanguination is death by excessiev loss of blood
• Healthy Pt's can endure a loss of 13% of total blood volume without serious medical difficulties (by comparison, blood donation typically takes 9% of donor's blood volume)

• Menorrhagia (heavy menstrual bleeding)
• Antihemorrhagic (stop bleeding)