You've probably heard the word 'hemorrhage', but what does it actually mean? In this lesson, we will define this medical term and take a look at the different hemorrhage classifications, and symptoms of each.
Hemorrhage Defined
Bill is a bloody mess as he is brought into the emergency room. He was using a chainsaw that kicked back while cutting a fallen tree branch in his backyard, and now has a deep cut across his torso. The ER team has seen far worse and can save his life, but his injury is a good example of a hemorrhage. In simplest terms, ahemorrhage is when blood vessels rupture, often due to an injury, resulting in excessive bleeding. A hemorrhage can be either external or internal (which is harder to detect). Let's take a look at the Advanced Trauma Life Support (ATLS) classification of hemorrhage, along with the symptoms present in each class.
Hemorrhage Classes
ATLS classes divide hemorrhage into four classes, based on the amount of blood lost. These four classes increase in severity, with Class 1 the least severe and Class 4 the most dangerous.
Class 1
The adult human body contains roughly five liters of blood. In the Class 1, or minimal stage of hemorrhage, there is less than 15%, or approximately 750ml, of blood loss. Patients still tend to have normal pulse rates and blood pressure. They are unlikely to have any further major medical problems because of the blood loss. Consider that a blood donation is about 450-500ml, and has very few side effects.
Class 2
Class 2, or mild hemorrhage, is defined as a 15-30% blood loss amount. In an adult, this would be equivalent to losing 750 to 1500 ml, which is about the equivalent of one or two bottles of wine.
Symptoms include a rapid heart rate, decreased pulse in the arms and legs, and an increased respiratory rate. The patient might be irritable or mentally altered and combative. His skin might be cooler to the touch and have delayed capillary refill. Urine production may be decreased, and have a higher concentration of other substances than normal. Thankfully for Bill, quick medical treatment means that his bleeding didn't progress beyond this class.
Class 3
Moderate blood loss of 30-40% of total volume is considered Class 3 hemorrhage. This would be like losing a 2-liter soda bottle worth of blood. At this stage, blood pressure will drop, and heart and respiration rates will rise. The patient's mental status may shift to a lethargic or irritable state, and he may experience a diminished pain response. The skin will not only feel cool but begin to lose color.
Class 4
Severe blood loss, or Class 4 hemorrhage, is defined as blood loss greater than than 40%. This class is characterized by severely high heart and respiration rates, along with dangerously low blood pressure. A lethargic state may progress to a coma. The skin and extremities will feel cold and begin turning blue, a condition known as cyanosis. Patients with Class 4 hemorrhage will be unable to produce or pass urine.
Lesson Summary
A hemorrhage is the term for when blood vessels rupture, often due to an injury, resulting in excessive bleeding. They are classified according to Advanced Trauma Life Support (ATLS) standards. The degree of severity places it into one of four classes, with Class 4 being the most dangerous.
Class 1 is less than 15% of blood volume loss, and is comparable to a blood donation. Class 2 is blood loss of between 15% and 30%, and can involve additional medical complications such as increased heart and respiration rates, mental status changes, and impaired urine production. Class 3 blood loss of 30-40% shows an advancement of the Class 2 symptoms. In Class 4, the patient loses more than 40% of blood volume and risks coma, experiences major skin and temperature changes, and can no longer produce urine.
Side Lesson from university Moodle website
Hemorrhage (i.e. bleeding) is a discharge of blood from the vascular compairtment to the exterior of the body or into nonvascular body spaces.
Mechanisms of hemorrhages
1. By destruction of the blood vessel’s wall (f.e. trauma, rupture of aneurysm).
2. By diapedesis of erythrocytes because of the increased permeability of the vascular wall (f.e. intoxication, hypoxia).
3. By ulceration of the vessel’s wall (f.e. ulcer of stomach, necrosis of tumor, pulmonary tuberculosis).
Thus a severe decrease in the number of platelets (thrombocytopenia) or a deficiency of a coagulation factor (e.g., factor VIII in hemophylia) is assosiated with spontaneous hemorrhages unrelated to any apparent trauma.
Types of hemorrhages according to the site of origin
1. Cardiac, as following a penetrating heart wound.
2. Arterial, due to trauma and rupture of a dissecting aneurysm.
3. Capillary, which is usually due to trauma, inherent vessel wall weakness, or a coagulation defect.
4. Venous, which is usually caused by trauma or surgical operation, from esophageal varices.
Types of internal hemorrhages
• Petechia – a small mucosal or serosal hemorrhage or minute punctate hemorrhage usually in the skin or conjunctiva.
• Purpura or hemorrhagic infiltration - the accumulation of some erythrocytes in tissue between cells.
• Ecchymoses or bruise - the superficial large extravasations of blood into the skin and mucous membranes. Following a bruise in association with coagulation defect, an initially purple discoloration of the skin turns green and then yellow before resolving, a sequence that reflects the progressive oxidation of bilirubin released from the hemoglobin of degraded of red blood cells. A good example of an eccxymosis is a “black eye”.
• Hematoma - a grossly visible localized accumulation of the blood in the soft tissue.
Types of hemorrhages in body cavities
• Hemothorax – hemorrhage in the pleural cavity.
• Hemopericardium – hemorrhage in the pericardium cavity.
• Hemoperitoneum – hemorrhage in the abdomen cavity.
• Hemoarthrosis – hemorrhage in the joint cavity.
External hemorrhages may be such as:
• Melena is deposition of the blood in the faces (excrement or stool) due to hemorrhage from ulcer of stomach, polip or ulcer of intestines.
• Hemoptyesis is hemorrhage from lungs.
• Metrorrhagia is hemorrhage from uterus.
Outcomes of hemorrhages
• Coagulation of the blood.
• Organization and incapsulation of the hematoma.
• Brown cystic formatiom (in cerebral hematoma due to accumulation of hemosiderin).
• Purulent fusion of the hematoma.
In cases of death from acute massive hemorrhage, the most significant postmorten changes are gross rather then microscopic and consists in generalized pallor of tissue, collapse of the great veins, and a flabby, shrunken, gray spleen.
A sudden loss of 33% of blood volume may cause death, while loss of upto 50% of blood volume over a period of 24 hours may not be necessarily fatal. However chronic blood loss generally produces an iron deficiency anemia, whereas acute hemorrhage may lead to serious immediate consequences such as hypovolemic shock.
Mechanisms of hemorrhages
1. By destruction of the blood vessel’s wall (f.e. trauma, rupture of aneurysm).
2. By diapedesis of erythrocytes because of the increased permeability of the vascular wall (f.e. intoxication, hypoxia).
3. By ulceration of the vessel’s wall (f.e. ulcer of stomach, necrosis of tumor, pulmonary tuberculosis).
Thus a severe decrease in the number of platelets (thrombocytopenia) or a deficiency of a coagulation factor (e.g., factor VIII in hemophylia) is assosiated with spontaneous hemorrhages unrelated to any apparent trauma.
Types of hemorrhages according to the site of origin
1. Cardiac, as following a penetrating heart wound.
2. Arterial, due to trauma and rupture of a dissecting aneurysm.
3. Capillary, which is usually due to trauma, inherent vessel wall weakness, or a coagulation defect.
4. Venous, which is usually caused by trauma or surgical operation, from esophageal varices.
Types of internal hemorrhages
• Petechia – a small mucosal or serosal hemorrhage or minute punctate hemorrhage usually in the skin or conjunctiva.
• Purpura or hemorrhagic infiltration - the accumulation of some erythrocytes in tissue between cells.
• Ecchymoses or bruise - the superficial large extravasations of blood into the skin and mucous membranes. Following a bruise in association with coagulation defect, an initially purple discoloration of the skin turns green and then yellow before resolving, a sequence that reflects the progressive oxidation of bilirubin released from the hemoglobin of degraded of red blood cells. A good example of an eccxymosis is a “black eye”.
• Hematoma - a grossly visible localized accumulation of the blood in the soft tissue.
Types of hemorrhages in body cavities
• Hemothorax – hemorrhage in the pleural cavity.
• Hemopericardium – hemorrhage in the pericardium cavity.
• Hemoperitoneum – hemorrhage in the abdomen cavity.
• Hemoarthrosis – hemorrhage in the joint cavity.
External hemorrhages may be such as:
• Melena is deposition of the blood in the faces (excrement or stool) due to hemorrhage from ulcer of stomach, polip or ulcer of intestines.
• Hemoptyesis is hemorrhage from lungs.
• Metrorrhagia is hemorrhage from uterus.
Outcomes of hemorrhages
• Coagulation of the blood.
• Organization and incapsulation of the hematoma.
• Brown cystic formatiom (in cerebral hematoma due to accumulation of hemosiderin).
• Purulent fusion of the hematoma.
In cases of death from acute massive hemorrhage, the most significant postmorten changes are gross rather then microscopic and consists in generalized pallor of tissue, collapse of the great veins, and a flabby, shrunken, gray spleen.
A sudden loss of 33% of blood volume may cause death, while loss of upto 50% of blood volume over a period of 24 hours may not be necessarily fatal. However chronic blood loss generally produces an iron deficiency anemia, whereas acute hemorrhage may lead to serious immediate consequences such as hypovolemic shock.
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