(ICUs), sometimes known as intensive
treatment units (ITUs), contain electronic
equipment to monitor vital functions
such as blood pressure and heart-rate
and rhythm. Frequently, patients in these
units require mechanical ventilation, in
which a machine takes over or assists
with breathing. Urine output, fluid bal-
ance, and blood chemistry are recorded
regularly. Fluids are given intravenously.
If nutrients are required, they are sup-
plied to the stomach through a tube.
There is a high ratio of specially trained
nursing and medical staff to patients.
(See also coronary care unit.)
inter-A prefix that means between, as
in intercostal(between the ribs). (See
also intra-.)
intercostalThe medical term for between
the ribs, as in the intercostal muscles,
thin sheets of muscle between each rib.
intercourse, painfulPain during sex-
ual intercourse, known medically as
dyspareunia, which can affect both men
and women. Pain may be superficial
(around the external genitals) or deep
(within the pelvis).
In men, superficial pain may be due to
anatomical abnormalities such as chor-
dee(bowed erection) or phimosis(tight
foreskin). Prostatitismay cause a wide-
spread pelvic ache, a burning sensation
in the penis, or pain on ejaculation.
Scarring (after childbirth, for example)
and lack of vaginal lubrication, especially
after the menopause, may cause painful
intercourse in women. Psychosexual dys-
functionmay also cause pain during
intercourse. Vaginismus, a condition in
which the muscles of the vagina go into
spasm, is usually psychological in ori-
gin. Deep pain is frequently caused by
pelvic disorders (such as fibroids, endo-
metriosis, ectopic pregnancy, or pelvic
inflammatory disease due to sexually
transmitted infections), disorders of the
ovary (such as ovarian cysts), and disor-
ders of the cervix. Other causes are
cystitisand urinary tract infections.
Treatment is directed at the underly-
ing cause of the pain. If the discomfort
is psychological in origin, special coun-
selling may be needed (see sex therapy).
interferonA protein produced natur-
ally by body cells in response to viral
infections and other stimuli. It inhibits
viral multiplication and increases the
activity of natural killer cells (a type of
lymphocytethat forms part of the body’s
immune system). It is also produced
artificially for use in treatment of a
number of disorders. There are 3 main
types: interferon alfa is used in the
treatment of certain lymphomas, a type
of leukaemia, and chronic hepatitis B
and C. Interferon beta is used in the
treatment of relapsing multiple sclerosis.
Interferon gamma is used to reduce the
risk of serious infections in some types
of immunodeficiency. Adverse reactions
include fever, headaches, lethargy, de-
pression, and dizziness.
intermittent claudicationA cramping
pain in the legs due to inadequate
blood supply (see claudication).
intersexA group of abnormalities in
which the affected person has ambigu-
ous genitalia (abnormal external sex
organs) or external genitalia that have
the opposite appearance to the chro-
mosomal sex of the individual (see sex
determination).
interstitial Referring to gaps (interstices)
between cells, tissues, or other body
structures. For example, tissue fluidbe-
tween body cells is known as interstitial
fluid. (See also interstitial radiotherapy.)
interstitial pulmonary fibrosisScar-
ring of lung tissue mainly involving the
alveoli. There are a number of causes,
including occupational exposure to
dusts and fibrosing alveolitis, which is
an autoimmune disorder.
interstitial radiotherapyTreatment of
a cancerous tumour by inserting radio-
active material into the growth or into
neighbouring tissue. Using this method,
also called brachytherapy, radiation can
be targeted at the diseased area.
Radioactive material (usually artificial
radioisotopes) contained in wires, small
tubes, or seeds is then implanted into
or near the diseased tissue under general
anaesthesia. The material is left in place
for variable amounts of time depending
on the radioactive substance and the
tumour being treated. (See also intra-
cavitary therapy; radiotherapy.)
intertrigoInflammation of the skin due
to 2 surfaces rubbing together. IntertrigoINTER- INTERTRIGO
I