Blood plasma
Blood plasma was the liquid in which blood cells were suspended.

When Dr. McCoy and Nurse Chapel were preparing for surgery on Sarek's heart, an operation that "would require tremendous amounts of blood for the patient", Chapel informed McCoy that she had checked the blood bank and told him that there was not enough Vulcan blood or plasma aboard the  for the operation, forcing them to look for alternate sources. ()

In 2371 during surgery on Bareil Antos, Dr. Bashir was forced to increase the plasma levels due to the loss of arterial pressure and the cardiac arrest issues after Bareil began hemorrhaging. ()

When Jake Sisko and Dr. Bashir found themselves on Ajilon Prime in the middle of a war zone in 2373, a Bolian orderly and a nurse were looking for blood plasma for transfusions as they cared for the injured from the attacks by the Klingons. ()

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Anatomy
Physiology