Types and Causes of Bleeding
- Upper head: Intracranial hemorrhage, cerebral hemorrhage, intracerebral hemorrhage, subarachnoid hemorrhage, ovarian bleeding
- Anus: Melena (upper gastrointestinal bleeding), hematochezia (lower gastrointestinal bleeding)
- Vascular: Ruptured aneurysm, aortic transection, iatrogenic injury
- Traumatic injury: Abrasion, excoriation, hematoma, laceration, incision, puncture wound, contusion, crushing injuries, ballistic trauma
- Medical condition: Intravascular changes, intramural changes, extravascular changes
Complications of Bleeding
- Exsanguination
- Hypovolemic shock
- Coma
- Shock
Hemostasis (Stopping or Controlling Bleeding)
- Importance in first aid and surgery
- Platelets and the coagulation system
- NSAIDs and increased bleeding risk
- Coagulation factors and deficiencies
- Von Willebrand disease and other bleeding disorders
Statistics and Key Points
- Healthy person can endure a loss of 10-15% of total blood volume without serious medical difficulties
- Blood donation typically takes 8-10% of the donor's blood volume
- Internal bleeding can be hidden and may not be readily apparent
- Bleeding from bodily orifices may signal internal bleeding
- Bleeding from medical procedures can occur and falls under traumatic injury category
Diagnosis, Classification, and Management of Bleeding
- Dioxaborolane chemistry enables radioactive fluoride labeling of red blood cells, allowing for positron emission tomography (PET) imaging of intracerebral hemorrhages
- Wound assessment is important in the diagnosis and imaging of hemorrhages
- A subconjunctival hemorrhage is a common post-LASIK complication
- Hemosiderin-laden alveolar macrophages can be seen in a pulmonary hemorrhage
- Hemorrhaging is classified into four classes (Class I, Class II, Class III, Class IV) based on the amount of blood loss and its impact on vital signs
- The American College of Surgeons uses a similar classification system for hypovolemic shock
- Class I hemorrhage involves up to 15% of blood volume and usually does not require fluid resuscitation
- Class II hemorrhage involves 15-30% of blood volume and may exhibit changes in vital signs and behavior
- Class III hemorrhage involves loss of 30-40% of circulating blood volume and requires fluid resuscitation with crystalloid and blood transfusion
- Class IV hemorrhage involves loss of 40% of circulating blood volume and aggressive resuscitation is necessary to prevent death
- There is no universally accepted definition of massive hemorrhage, but several criteria can be used to identify the condition
- The World Health Organization has developed a standardized grading scale to measure the severity of bleeding
- The severity of bleeding can be assessed based on the grade assigned
Bleeding, hemorrhage, haemorrhage or blood loss is blood escaping from the circulatory system from damaged blood vessels. Bleeding can occur internally, or externally either through a natural opening such as the mouth, nose, ear, urethra, vagina or anus, or through a puncture in the skin. Hypovolemia is a massive decrease in blood volume, and death by excessive loss of blood is referred to as exsanguination. Typically, a healthy person can endure a loss of 10–15% of the total blood volume without serious medical difficulties (by comparison, blood donation typically takes 8–10% of the donor's blood volume). The stopping or controlling of bleeding is called hemostasis and is an important part of both first aid and surgery.
| Bleeding | |
|---|---|
| Other names | Hemorrhaging, haemorrhaging, blood loss |
 | |
| A bleeding wound in the finger | |
| Specialty | Emergency medicine, hematology |
| Complications | Exsanguination, hypovolemic shock, coma, shock |
