INTRODUCTION- Bleeding, technically known as hemorrhaging or hemorrhaging is blood escaping from the circulatory system. Bleeding can occur internally, where blood leaks from blood vessels inside the body, or externally, either through a natural opening such as the mouth, nose, ear, urethra, vagina or anus, or through a break in the skin. Hypovolemia is a massive decrease in blood volume, and death by excessive loss of blood is referred to as exsanguinations.
• Class I Hemorrhage involves up to 15% of blood volume. There is typically no change in vital signs and fluid resuscitation is not usually necessary.
• Class II Hemorrhage involves 15-30% of total blood volume. A patient is often tachycardia (rapid heartbeat) with a narrowing of the difference between the systolic and diastolic blood pressures. The body attempts to compensate with peripheral vasoconstriction. Skin may start to look pale and be cool to the touch. The patient may exhibit slight changes in behavior. Volume resuscitation with crystalloids (Saline solution or Lactated Ringer’s solution) is all that is typically required. Blood transfusion is not typically required.
• Class III Hemorrhage involves loss of 30-40% of circulating blood volume. The patient’s blood pressure drops, the heart rate increases, peripheral hypo perfusion (shock), such as capillary refill worsens, and the mental status worsens. Fluid resuscitation with crystalloid and blood transfusion are usually necessary.
• Class IV Hemorrhage involves loss of >40% of circulating blood volume. The limit of the body’s compensation is reached and aggressive resuscitation is required to prevent death.
Bleeding arises due to traumatic injury, underlying medical condition, or a combination.
Traumatic bleeding is caused by some type of injury. There are different types of wounds which may cause traumatic bleeding. These include:
• Abrasion – Also called a graze, this is caused by transverse action of a foreign object against the skin, and usually does not penetrate below the epidermis
• Excoriation – In common with Abrasion, this is caused by mechanical destruction of the skin, although it usually has an underlying medical cause
• Hematoma – Caused by damage to a blood vessel that in turn causes blood to collect under the skin.
• Laceration – Irregular wound caused by blunt impact to soft tissue overlying hard tissue or tearing such as in childbirth. In some instances, this can also be used to describe an incision.
• Incision – A cut into a body tissue or organ, such as by a scalpel, made during surgery.
‘Medical bleeding’ denotes hemorrhage as a result of an underlying medical condition (i.e. causes of bleeding that are not directly due to trauma). Blood can escape from blood vessels as a result of 3 basic patterns of injury:
• Intravascular changes – changes of the blood within vessels (e.g. ↑ blood pressure, ↓ clotting factors)
• Intramural changes – changes arising within the walls of blood vessels (e.g. aneurysms, dissections, AVMs, vasculatures)
• Extra vascular changes – changes arising outside blood vessels (e.g. H pylori infection, brain abscess, brain tumor)