Primary haemostasis starts with vasoconstriction triggered by vessel injury, and continues until vessel integrity is restored and bleeding stops. As well as lacerations, vascular damage may result from trauma, excessive turbulense, indwelling catheters, or inflammation (endocarditis). Plates respond to vessel injusry be adhhereing to vascular subendothelium (adhesion) and to other platelets (primary aggreggation), changing shape and releaseing substances which promote vasoconstriction and activate more platelets (the relsease reaction). Platelet contraction and aaggregation triggered by the substances released by the platelets (secondary aggregation) continue until the injusty is sealed by a fragile platelet plug. | Primary haemostasis starts with vasoconstriction triggered by vessel injury, and continues until vessel integrity is restored and bleeding stops. As well as lacerations, vascular damage may result from trauma, excessive turbulense, indwelling catheters, or inflammation (endocarditis). Plates respond to vessel injusry be adhhereing to vascular subendothelium (adhesion) and to other platelets (primary aggreggation), changing shape and releaseing substances which promote vasoconstriction and activate more platelets (the relsease reaction). Platelet contraction and aaggregation triggered by the substances released by the platelets (secondary aggregation) continue until the injusty is sealed by a fragile platelet plug. |