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3 Minimum Database for

Intracranial Surgery

Theresa E. Pancotto

Introduction Medical History
The more common indications for intracranial surgery in the A conversation with clients about spectrum of clinical signs and
veterinary population include tumor resection or biopsy, biopsy duration may help identify extraneural systemic disorders and will
of other brain disorders (inflammatory, metabolic, genetic), fora- guide formulation and ranking of differential diagnoses. A list of
men magnum decompression for patients with caudal occipital current medications and knowledge of their side effects will guide
malformation and syringohydromyelia, ventriculoperitoneal testing. For example, patients on phenobarbital for seizures associ-
shunt placement for patients with hydrocephalus, decompression ated with a cerebral mass should have accurate serum concentra-
of traumatic brain injury, and drainage of intracranial abscesses. tions available as well as recent evaluation of liver function. In
Patient characteristics such as age and concurrent disease as well canines, heartworm status should be known for all patients
as the nature of the inciting cause will influence the specific tests undergoing anesthesia as heartworm disease can contribute to car-
that are selected as part of the minimum database. The veterinary diovascular problems and complicate anesthesia. For felines, feline
literature is insufficiently rigorous to allow for complete assess- leukemia virus (FeLV)/feline immunodeficiency virus (FIV) status
ment of the utility of a general panel of preoperative laboratory should be determined. Occasionally, environmental factors will
testing. Therefore, recommendations for minimum database impact selection of testing (e.g., the patient lives in a smoking
tests required prior to intracranial surgery are often based on the household or tick exposure has been documented).
results of physical examination identifying comorbid conditions,
anticipation and avoidance of specific surgical complications, Neurological Assessment
and severity of existing neurological signs. Selective preoperative A neuroanatomical diagnosis is established prior to surgery based
testing also helps reduce medical costs. In North American on the findings of a complete neurological examination. A list of
human hospitals, estimates show that $30–40 billion per year is differentials is subsequently generated based on signalment, his-
spent on preoperative testing of which about half may be unnec- tory, and clinical signs. In patients presented for intracranial emer-
essary [1]. The following is an overview of how concurrent gencies, an abbreviated examination may be performed and
diseases and surgical procedure will influence minimum data- imaging and surgery may follow promptly. The Small Animal Coma
base testing. Scale (SACS)/Modified Glasgow Coma Scale (MGCS) provides the
attending veterinarian with rapid assessment of neurological
function and allows detection of signs associated with elevated
Preanesthetic intracranial pressure (ICP) [2,3]. The SACS includes evaluation of
It is important not to overlook the value of the initial medical level of consciousness, motor function, and select brainstem
history and neurological and physical examinations in identifying reflexes. Patients with depressed sensorium are at increased risk of
concurrent disorders that may have an important bearing on selection aspiration pneumonia [4]. Anisocoria, weakness, or absence of
of diagnostics and patient management. pupillary light and/or oculocephalic reflexes indicates intracranial

Current Techniques in Canine and Feline Neurosurgery, First Edition. Edited by Andy Shores and Brigitte A. Brisson.
© 2017 John Wiley & Sons, Inc. Published 2017 by John Wiley & Sons, Inc.
Companion website: www.wiley.com/go/shores/neurosurgery

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