Download activated partial thromboplastin time (APTT) (aPTT) (PTT) the period

activated partial thromboplastin time (APTT) (aPTT) (PTT) the period required for clot
formation in recalcified blood plasma after contact activation and the addition of platelet
substitutes; used to address the intrinsic and common pathways of coagulation.
bleeding time the duration of bleeding after controlled, standardized puncture of the earlobe or
forearm; a relatively inconsistent measure of capillary and platelet function.
circulation time the time required for blood to flow between two given points.
clotting time , coagulation time the time required for blood to clot in a glass tube.
inertia time the time required to overcome the inertia of a muscle after reception of a stimulus
from a nerve.
one-stage prothrombin time prothrombin t.
prothrombin time (PT) the rate at which prothrombin is converted to thrombin in citrated blood
with added calcium; used to assess the extrinsic coagulation system of the blood.
reaction time the time elapsing between the application of a stimulus and the resulting reaction.
stimulus-response time reaction t.
thrombin time (TT) the time required for plasma fibrinogen to form thrombin, measured as the
time for clot formation after exogenous thrombin is added to citrated plasma.
clotting time
the time required for blood to form a clot, tested by collecting 4 mL of blood in a glass tube and
examining it for clot formation. The first appearance of a clot is noted and timed. The normal
coagulation time in glass tubes is 5 to 15 minutes. This simple test has been used to diagnose
hemophilia, but it does not detect mild coagulation disorders. Its chief application is in monitoring
anticoagulant therapy. It is rarely used in clinical practice. Also called coagulation time.
Compare bleeding time.
time a measure of duration. See under adjectives for specific times, such as BLEEDING TIME.
activated partial thromboplastin time (APTT, aPTT) the period required for CLOT formation in
recalcified blood PLASMA after contact activation and the addition of PLATELET substitutes such as
brain CEPHALINS or similar PHOSPHOLIPIDS; used to assess the coagulation PATHWAYS. A prolonged
aPTT can indicate a deficiency of any of various COAGULATION FACTORS, including factors XII, XI,
IX, VIII, X, V, and II, and FIBRINOGEN.
AEC minimal response time the shortest duration at which x-ray exposure can be terminated by
automatic exposure control.
atrioventricular sequential time a fixed nonprogrammable interval that extends from the atrial
stimulus to the ventricular stimulus.
bleeding time the time required for a standardized wound to stop bleeding; used as a test for
platelet disorders; see also BLEEDING TIME.
circulation time the time required for blood to flow between two given points; see also
CIRCULATION TIME.
clotting time (coagulation time) the time required for blood to clot in a glass tube; see also
CLOTTING.
cold ischemia time the time between the placement of a traumatically amputated body part in
ice and the time of surgical replantation.
inertia time the time required to overcome the inertia of a muscle after reception of a stimulus.
ischemia time the total time between traumatic amputation of a limb or portion of a limb and its
surgical reimplantation; it is the sum of warm and cold ischemia times.
minimal response time in radiology, the shortest possible exposure time for an x-ray film to be
exposed automatically.
one-stage prothrombin time PROTHROMBIN TIME.
prothrombin time see PROTHROMBIN TIME.
real time a term used to describe a recording device that shows events simultaneously to their
occurrence.
R peak time intrinsicoid deflection.
thrombin time the time required for plasma fibrinogen to form thrombin; see also THROMBIN TIME.
warm ischemia time the time interval between traumatic amputation of a limb or part and its
placement on ice.
clotting
the formation of a jellylike substance over the ends or within the walls of a blood vessel, with
resultant stoppage of the blood flow. Clotting is one of the natural defense mechanisms of the
body when injury occurs. A clot will usually form within 5 minutes after a blood vessel wall has
been damaged. The clotting mechanism is triggered by the platelets, which disintegrate as they
pass over rough places in the injured surface. As they disintegrate they release serotonin and
thromboplastin. Serotonin causes constriction of the blood vessels and reduction of local blood
pressure. Thromboplastin unites with calcium ions and other substances which promote the
formation of fibrin. When examined under a microscope, a clot consists of a mesh of fine threads
of fibrin in which are embedded erythrocytes and leukocytes, small amounts of fluid (serum), and
platelets.
clotting factors
a series of plasma proteins which are related through a complex cascade of enzyme-catalyzed
reactions involving the sequential cleavage of large protein molecules to produce peptides, each
of which converts an inactive zymogen precursor (factor II) into an active enzyme (Iia) leading to
the formation of a fibrin clot. They are designated by Roman numerals, and an additional 'a' to
indicate the activated state. They are: factor I (fibrinogen), factor II (prothrombin), factor III (tissue
thromboplastin), factor IV (calcium), factor V (proaccelerin), factor VI (no longer considered active
in hemostasis), factor VII (proconvertin), factor VIII (antihemophilic factor), factor IX (plasma
thromboplastin component; Christmas factor), factor X (stuart factor), factor XI (plasma
thromboplastin antecedent), factor XII (hageman factor), factor XIII (fibrin stabilizing factor).
clotting time
the time required for blood to clot in a glass tube; a measure of the intrinsic system of
coagulation. In the Lee-White method, blood in test tubes is maintained at a constant temperature
and examined regularly until clotting occurs; the test can be also be performed in capillary tubes.
Called also coagulation time. Less sensitive and now less often used than the activated
coagulation time.
tissue clotting factor
clotting factor III; tissue thromboplastin.
Patient discussion about clotting time.
Q. i have a small blood clot above my heart that bother me dome times. i also have had
bypass sugary this past march, my heart doctor says it has nothing to do with my heart, has
anyone else had this problem and if so what or how have you dealt with it?
A. laddie, my uncle had something similar (i think so anyway) but i'm not sure i understand what
you mean by "above the heart" ? by uncle had a blood clot that was formed in the heart arteries
and he had to a procedure and open it up. but you'll need to give me more info