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Chapter 28: Guidelines for Postoperative Medical Care of the Neurosurgical Patient 253

Table 28.4 Common gastric motility agents and their dose rates. ascending/descending myelomalacia, uncontrollable pain typically
develops. Monitoring for myelomalacia involves twice‐daily moni-
Drug Continuous‐rate Individual doses
infusion toring of the neurological status or more frequently if it is suspected.
Evaluation of the cutaneous trunci muscle reflex (panniculus “cut‐
Metoclopramide 1–2 mg/kg daily 0.3 mg/kg IV every 8 hours off”) is important as ascending loss of this reflex is an early sign of
Cisapride – 0.1–0.5 mg/kg PO every 8 myelomalacia [48]. Progression from upper motor neuron signs to
hours
Erythromycin – 0.5–1.0 mg/kg PO, IV every 8 lower motor neuron signs with loss of patella reflex is also an indi-
hours cation of possible myelomalacia. There is currently no known treat-
ment or prevention for myelomalacia, and euthanasia is usually
Source: Doses modified from Plumb’s Veterinary Drug Handbook [20]. recommended prior to development of respiratory failure.
Parenteral Nutrition Repeat Imaging
Parenteral nutrition is indicated whenever the gastrointestinal tract Residual disc material was found to be present in 100% of dogs after
is not working well enough to digest or absorb sufficient nutrients, hemilaminectomy for thoracolumbar disc herniation [49]. A more
there is persistent vomiting or gastric stasis, or the risk of aspiration recent study found residual material in 44% of dogs following mini‐
is high due to coma or mechanical ventilation. Parenteral nutrition hemilaminectomy [50]. Although the majority of these patients
consists of either total parenteral nutrition (TPN), which essentially progress normally postoperatively, if a patient fails to improve as
provides most of the caloric and amino acid requirements, or par- expected or shows deterioration in neurological status, early repeat
tial parenteral nutrition (PPN), which provides only a portion of imaging is recommended to document adequate decompression
the caloric and amino acid requirements. PPN can be administered and removal of disc material or tumor or rule out the presence of a
via peripheral veins. TPN requires a central venous line due to the compressive hematoma.
high osmolarity of the solution and will cause severe phlebitis and
thrombosis if administered through a peripheral vein [46]. Serial
monitoring of blood glucose is recommended when TPN or PPN is Incisional Care
initiated in patients with intracranial disease in which hyperglyce- Following surgery, the incision should be monitored twice daily for
mia should be avoided. signs of pain, redness, swelling, or discharge. A protective bandage
Parenteral nutrition solutions need to be mixed aseptically and can be applied to cover the incision for the first 24 hours until matu-
can be stored refrigerated for up to 7 days and at room temperature ration of the fibrin clot (Figure 28.6). If skin sutures have been used,
for up to 2 days. The solution should be protected from light and no they are typically removed at 10–14 days.
other medications should be mixed into the solution administra-
tion set/line. One of the complications associated with parenteral
nutrition is sepsis due to growth of contaminants in the solution, A
which is reported in 5–8% of patients [47].

Monitoring Neurological Status
Following both intracranial surgery and spinal surgery, there is an
expected course of recovery. If a patient does not follow the expected
course of improvement or has significant deterioration in neuro-
logical status, repeat imaging may be indicated. In humans, postop-
erative imaging following spinal or intracranial surgery is standard
to ensure adequate removal of the tumor or that decompression has
occurred. In veterinary medicine, immediate postoperative imag-
ing is rarely performed due to the associated financial cost.
Following intracranial surgery, progressive brain edema can occur
for up to 48 hours and can persist for a week or more. During this time,
the patient should be monitored for neurological deterioration. General B
physical parameters that should be assessed include heart rate and
rhythm, respiratory rate and character, blood pressure, blood gases,
oxygenation, and urine production. Neurological parameters that can
be evaluated to assess changes in neurological status include pupil size
and responsiveness to light, level of consciousness, and ability of the
patient to move or walk. Individual cranial nerves can also be assessed
to determine if there is underlying neurological deterioration.

Ascending Myelomalacia
Another cause of deteriorating neurological status in patients that
are nociception‐negative prior to or following decompressive Figure 28.6 (A) Immediate postoperative incision following dorsolateral
thoracolumbar spinal surgery is ascending/descending myelomala- approach to the thoracolumbar spine for pediculectomy. (B) Semi‐occlusive
cia. In the early postoperative period, dogs are typically comfortable dressing used to cover incisions in the immediate postoperative period after
following the removal of the compressive disc. In patients with spinal surgery.