The Valsalva maneuver, which can be produced by straining at defecation or even
moving in bed, raises ICP and is to be avoided. Stool softeners may be prescribed. If
the patient is alert and able to eat, a diet high in fiber may be indicated. Abdominal
distention, which increases intra-abdominal and intrathoracic pressure and ICP, should
be noted. Enemas and cathartics are avoided if possible. When moving or being turned
in bed, the patient can be instructed to exhale (which opens the glottis) to avoid the
Valsalva maneuver.
Mechanical ventilation presents unique problems for the patient with increased ICP.
Before suctioning, the patient should be preoxygenated and briefly hyperventilated
using 100% oxygen on the ventilator (Hickey, 2003). Suctioning should not last longer
than 15 seconds. High levels of positive end-expiratory pressure (PEEP) are avoided,
because they may decrease venous return to the heart and decrease venous drainage
from the brain through increased intrathoracic pressure (Hickey, 2003).
Activities that increase ICP, as indicated by changes in waveforms, should be avoided
if possible. Spacing of nursing interventions may prevent transient increases in ICP.
During nursing interventions, the ICP should not increase more than 25 mm Hg, and it
should return to baseline levels within 5 minutes. Patients with increased ICP should
not demonstrate a significant increase in pressure or change in the ICP waveform.
Patients with the potential for a significant increase in ICP may need sedation and a
paralytic agent before initiation of nursing activities (Hickey, 2003).
Emotional stress and frequent arousal from sleep are avoided. A calm atmosphere is
maintained. Environmental stimuli (eg, noise, conversation) should be minimal.
Maintaining Negative Fluid Balance
The administration of various osmotic and loop diuretics is part of the treatment
protocol to reduce ICP. Corticosteroids may be used to reduce cerebral edema (except
when it results from trauma), and fluids may be restricted (Brain Trauma Foundation,
2003). All of these treatment modalities promote dehydration.
Skin turgor, mucous membranes, urine output, and serum and urine osmolality are
monitored to assess fluid status. If IV fluids are prescribed, the nurse ensures that they
are administered at a slow to moderate rate with an IV infusion pump, to prevent too-
rapid administration and avoid overhydration. For the patient receiving mannitol, the
nurse observes for the possible development of heart failure and pulmonary edema,
because the intent of treatment is to promote a shift of fluid from the intracellular
compartment to the intravascular system, thus controlling cerebral edema.
For patients undergoing dehydrating procedures, vital signs, including blood pressure,
must be monitored to assess fluid volume status. An indwelling urinary catheter is
inserted to permit assessment of renal function and fluid status. During the acute phase,
urine output is monitored hourly. An output greater than 250 mL/hour for 2 consecutive
hours may indicate the onset of diabetes insipidus (Suarez, 2004). These patients also
need careful oral hygiene, because mouth dryness occurs with dehydration. Frequently
rinsing the mouth with nondrying solutions, lubricating the lips, and removing
encrustations relieve dryness and promote comfort.
Preventing Infection
Risk for infection is greatest when ICP is monitored with an intraventricular catheter,
and the risk of infection increases with the duration of the monitoring (Park, Garton,
Kocan, et al., 2004). Most health care facilities have written protocols for managing
these systems and maintaining their sterility; strict adherence to the protocols is
essential.