In the _coma_ of _uraemia_ or of _diabetes_ there is no true paralysis,
nor is there stertor. The urine contains albumin or sugar, and there
may be oedema of the feet and legs.

_Prognosis._--The prognosis depends so much on the nature and extent
of the injury to the brain that it is impossible to formulate any
general statements with regard to it. It may be said, however, that
the symptoms which indicate a bad prognosis are immediate rise of
temperature, particularly if it goes above 104 deg. F., the early onset of
muscular rigidity, extreme and persistent contraction of the pupils,
with loss of the reflex to light, conjugate deviation of the eyes, and
the early appearance of bed-sores.

In the majority of cases compression ends fatally in from two to seven
days. On the other hand, recovery may ensue after the stuporous
condition has lasted for several weeks.

The _treatment_ of compression is considered with the different
lesions which cause it; the principle in all cases being to remove, if
possible, the cause of the increased pressure within the skull.

#Traumatic Oedema.#--In practice, cases are frequently met with,
particularly in children, that do not conform to the classical
description of either concussion, cerebral irritation, or compression.
The injury may be followed by a varying degree of concussion which
soon passes off but leaves the patient in a listless, drowsy state
that may persist for days or even for weeks. The cerebration is
disturbed, so that while the patient is not unconscious, he is
apathetic and has lost his bearings and fails to recognise where or
with whom he is. He complains of headache, there is tenderness on
percussion over the skull, the knee jerks are diminished or absent,
but there is no motor paralysis. In some cases there are localised
jerkings, in others generalised convulsive attacks during which the
patient becomes deeply cyanosed. The condition differs from
compression due to middle meningeal haemorrhage in that it is less
severe and is not steadily progressive.

When the symptoms are localised, the condition is probably due to
oedematous infiltration of the injured portion of brain; when
generalised, to increased intra-cranial tension from serous effusion
into the arachno-pial space.

The _treatment_ consists in diminishing the intra-cranial tension by
purgation, leeches, bleeding, or lumbar puncture, or if life is
threatened, by opening the skull over the seat of injury