intussusception Infolding (prolapse) of a portion of the intestine within another immediately adjacent portion of intestine, which predominantly affects children. Intussusception decreases the supply of blood to the affected part of the intestine and frequently leads to intestinal obstruction. The pressure created by the two walls of the intestine pressing together causes inflammation and swelling,…
intubate To put a tube in, commonly used to refer to the insertion of a breathing tube into the trachea for mechanical ventilation. For example, as a life-saving measure, an emergency room physician might intubate a patient who is not breathing adequately so that the lungs can be ventilated.
intron Part of a gene that is initially transcribed into the primary RNA transcript but is later removed from it when the exon sequences on either side of it are spliced together. Also known as intervening sequence.
introitus, vaginal The vaginal opening.
introitus, facial canal The entrance to the facial canal, a passage in the temporal bone of the skull through which the facial nerve travels.
introitus An entrance that goes into a canal or hollow organ.
intraventricular In the ventricle of the heart or the brain.
intravenous tension The pressure of the blood within a vein. Also known as venous pressure.
intravenous pyelogram An X-ray of the kidneys and urinary tract. Abbreviated IVP. Structures are made visible on an IVP by the injection of a contrast material.
intravenous immunoglobulin A sterile solution of concentrated antibodies extracted from healthy people that is administered directly into a vein. Abbreviated IVIG. IVIG is used to treat disorders of the immune system or to boost the immune response to serious illness. Also known as intravenous gamma globulin (IGG).
intravenous gamma globulin See intravenous immunoglobulin.
intravenous 1 Into a vein. For example, intravenous antibiotics are antibiotics in a solution that is administered directly into the venous circulation via a syringe or an intravenous catheter (tube). Abbreviated IV. 2 A solution that is administered intravenously. 3 The device that is used to administer an IV solution.