In general, symptoms and signs that suggest a rise in ICP including headache, vomiting without nausea, ocular palsies, altered level of consciousness, back pain and papilledema. If papilledema is protracted, it may lead to visual disturbances, optic atrophy, and eventually blindness.
In addition to the above, if mass effect is present with resulting displacement of brain tissue, additional signs may include pupillary dilatation, abducens palsies, and the Cushing’s triad. Cushing’s triad involves an increased systolic blood pressure, a widened pulse pressure, bradycardia, and an abnormal respiratory pattern.In children, a slow heart rate is especially suggestive of high ICP.
Irregular respirations occur when injury to parts of the brain interfere with the respiratory drive. Cheyne-Stokes respiration, in which breathing is rapid for a period and then absent for a period, occurs because of injury to the cerebral hemispheres or diencephalon. Hyperventilation can occur when the brain stem or tegmentum is damaged.
As a rule, patients with normal blood pressure retain normal alertness with ICP of 25-40 mmHg (unless tissue shifts at the same time). Only when ICP exceeds 40-50 mmHg do CPP and cerebral perfusion decrease to a level that results in loss of consciousness. Any further elevations wil l lead to brain infarction and brain death.
In infants and small children,the effects of ICP differ because their cranial sutures have not closed. In infants, the fontanels, or soft spots on the head where the skull bones have not yet fused, bulge when ICP gets too high. A swollen optic nerve is a reliable sign that ICP is elevated.