Pathology Of Hemorrhage Flashcards
What is hemorrhage?
Hemorrhage is the extravasation of blood from a damaged blood vessel.
How is hemorrhage classified?
Hemorrhage can be classified as acute or chronic, external or internal, minor (petechiae, ecchymosis) or major (involving organs).
What is the global burden of injury-related hemorrhage?
In 2000, injuries accounted for 9% of global mortality and 12% of disease burden. About 90% of injuries occur in low and middle-income nations.
What are the main causes of hemorrhage?
Causes include trauma, vascular defects (atherosclerosis, aneurysms), defective coagulation, and cancers.
How much blood can a healthy adult tolerate losing without symptoms?
Most adults can lose up to 14% of their blood volume without physical symptoms.
What are the stages of hemorrhage?
Class I: Up to 15% blood loss, Class II: 15-30% blood loss, Class III: 30-40% blood loss, Class IV: Over 40% blood loss.
What are the symptoms of Class II hemorrhage?
Symptoms include nausea, fatigue, pallor, cooling of extremities, tachycardia, and tachypnea.
What is the hallmark of hemorrhage morphology?
The hallmark is the collection of red blood cells outside vascular channels.
What are petechiae?
Petechiae are pinpoint non-blanching spots, less than 2 mm, affecting the skin and mucous membranes.
What are common causes of petechiae?
Causes include thrombocytopenia, platelet dysfunction, coagulation disorders, and loss of vascular integrity.
What are purpura?
Purpura are non-blanching spots greater than 2 mm, often associated with small vessel cutaneous vasculitis.
