Catheterization, venous: The insertion of a tiny tube (a catheter) into a peripheral or central vein to deliver fluids or medication. This is the most frequently used method for the administration of intravenous (IV) fluids and IV meds (medications).
The most common complications of venous catheterization are infiltration of fluid around the catheter, failure of the line to stay open, and infection somewhere along the length of the catheter (catheter sepsis).
Cathexis: In psychiatry, the concentration of psychic energy on an idea.
Cation: In chemistry, a positively charged ion. Pronounced cat-I-on. A cation is as opposed to an anion, which is a negatively charged ion.
- Cauda equina
Cauda equina: A bundle of spinal nerve roots that arise from the end of the spinal cord. The cauda equina comprises the roots of all the spinal nerves below the first lumbar (L1) vertebra in the lower back.
- Cauda equina syndrome
Impairment of the nerves in the cauda equina, characterized by dull pain in the lower back and upper buttocks and lack of feeling (analgesia) in the buttocks, genitalia, and thigh, together with disturbances of bowel and bladder function.
Caudad: Toward the feet (or, in embryology, toward the tail), as opposed to cranial. The spinal cord is caudad to the brain. For a more complete listing of terms used in medicine for spatial orientation, please see the entry to “Anatomic Orientation Terms”.