While not widely accessible, portable computerized axial tomography
(CT) scanning (Figure 22-1) has become available commercially and
is ideal for the intensive care unit (ICU) patient, who may be at
risk during transportation to and from the remotely located CT scanner.
CT scanning console in the foreground, with an ICU patient
in CT gantry in the background.
- ▪ Neurological emergency: Unexplained change in mental
status, obtundation, or neurological deficit
- ▪ CT scan with or without contrast is the standard approach
to the radiographic determination of intracranial anatomy and pathology.
- ▪ Noncontrast CT can be used to reveal intracranial hemorrhage,
large cerebrovascular events, skull trauma and evaluate ventricular
- ▪ Contrast enhancement is used to evaluate specific lesions
which will become more apparent to the presence of contrast in the
blood flowing through the lesion, that is, infection or tumor.
Clinical Pearls and Pitfalls
- ▪ Contrast
dye may be unnecessary for certain patients and contraindicated
for other (ie, renal insufficiency, contrast dye allergy).
- ▪ Contrast
dye can cause afferent arteriolar vasospasm in the kidney, and patients
with certain conditions (ie, diabetes, myeloma, renal insufficiency,
dehydration, and congestive heart failure) are at increased risk.
- ▪ Prophylactic
hydration reduces the risk of contrast nephropathy, as may prophylactic
administration of N-acetylcysteine.
Teichgraber UKM, Pinkernelle J, Jurgensen J, Ricke J, Kaisers
U. Portable computed tomography performed on the intensive care
unit. Intensive Care Med.