| Revision as of 07:39, 15 April 2003 editTristanb (talk | contribs)Extended confirmed users4,614 edits added very brief rationale behind separation, a few terms, and modified reference range.← Previous edit | Revision as of 16:34, 22 February 2004 edit undo195.92.168.172 (talk)No edit summaryNext edit → | ||
| Line 1: | Line 1: | ||
| '''Platelets''' are ]s that stick together to form ] clots. |
'''Platelets''' are ]s that stick together to form ] clots. They join together when exposed to the ] (as in a cut or disturbance of ]), though they are not cells in the conventional sense, but are fragmented pieces of ] ] released from the ] into the blood stream. | ||
| Platelets are separated, by ], from the rest of donated blood and given to patients who need them. A (see-through) bag of them is pale orange. They are separated because they don't survive the normal storage used for ]s, and must be stored separately. | Platelets are separated, by ], from the rest of donated blood and given to patients who need them. A (see-through) bag of them is pale orange. They are separated because they don't survive the normal storage used for ]s, and must be stored separately. | ||
Revision as of 16:34, 22 February 2004
Platelets are cells that stick together to form blood clots. They join together when exposed to the air (as in a cut or disturbance of blood vessel), though they are not cells in the conventional sense, but are fragmented pieces of megakaryocyte cytoplasm released from the bone marrow into the blood stream.
Platelets are separated, by centrifugation, from the rest of donated blood and given to patients who need them. A (see-through) bag of them is pale orange. They are separated because they don't survive the normal storage used for red blood cells, and must be stored separately.
A normal platelet count in a healthy person is between 150 and 400 (x 10/L of blood). People can live independently with a count as low as 20. People can live in hospital with a count as low as 5, but spontaneous bleeding gets to be a problem. That's when platelet transfusions have to be done. A low platelet count is called thrombocytopenia, having too many platelets is called thrombocytosis.
See Also: Haemostasis