Craniotomy for supratentorial tumor

Craniotomy for Supratentorial Tumor (CPT 61510, 61512)
General: Patients may be symptomatic or asymptomatic. Symptoms may be due to
location of tumor or due to increased ICP. You should know the location, kind (if known) and
size of the tumor(s), any neurological deficits and symptoms and if the patient is at risk for
increased ICP. Patients are often taking dilantin, tegretol or keppra and/or decadron.
Preop: Start an IV. Premedicate with up to 2 mg of midazolam depending on patient’s
mental status. None if altered mental status (prevent further increase in ICP).
Monitors: Routine monitors. Arterial and Foley catheters inserted after induction of
anesthesia.
Anesthesia: Goals are to decrease ICP (if high), to maintain adequate CPP (at least 70
mmHg) to prevent cerebral ischemia from brain retraction and to provide brain relaxation for
good surgical exposure. Patients typically receive 1-2 g of Cefazolin, and 4-10 mg of
decadron before skin incision, and if indicated up to 1 g/kg of mannitol on skin incision
(verify all with surgeon). Induction with propofol. In case of increased ICP, have patient
hyperventilate during preoxygenation and continue hyperventilation with mask as soon as
possible after induction of anesthesia. Fentanyl 5 µg /kg in divided doses throughout
induction, prior to intubation. Verify adequate neuromuscular blockade prior to intubation to
avoid coughing/straining. Tape eyes, insert esophageal temperature probe, and at least one
additional large bore IV. Patient position will depend on location of tumor. Maintain
anesthesia with propofol infusion and low dose inhalation agent (less than 0.5 MAC), and a
fentanyl infusion 2 µg/kg/hr. Use mild hyperventilation (PaCO2 30-35 mmHg). Maintain
euvolemia (Lactated Ringer’s) and neuromuscular relaxation (vecuronium or rocuronium). Once the bone flap is removed, have the surgeon assess the tightness of the dura. Decrease ICP further if necessary (pCO2, mannitol, propofol, head up etc.). Once the dura is open, the goal is to avoid “brain shift” so that stereotactic navigation system can be used optimally. Fentanyl infusion is usually stopped at the beginning of closure. Normalize pCO2 to facilitate spontaneous breathing at the end of the operation. Use of inhalation agents or
propofol is usually stopped about 10 min before end of surgery. Reverse residual
neuromuscular blockade once the Mayfield pins have been removed. Consider prophylactic
use of labetalol to attenuate emergence hypertension.
Potential complications: Postoperative seizures. Delayed awakening from anesthetics
and/or intracranial pathology. Postoperative intracranial bleeding.

Recovery: Wake patient up and extubate immediately after the operation to allow
neurologic examination. Coughing and bucking on the endotracheal tube must be
minimized. Use a hemodynamic monitor and supplemental oxygen during patient transport
to ICU. Prevent postoperative hypertension (labetalol) to avoid intracranial bleeding.

Source: http://neuroanesthesia.ucsf.edu/PDFs/Craniotomy_for_Supratentorial_Tumor.pdf