Acetazolamide to Prevent Post Operative CSF Leak

Transsphenoidal resection of sellar and parasellar tumors is associated with a significant
risk of intraoperative cerebrospinal fluid (CSF) leak (up to 25% for pituitary adenomas, and
nearly 100% for craniopharyngiomas and other complex tumors). Postoperative CSF leaks are
dangerous complications that can result in infectious meningitis. In patients with
intraoperative CSF leaks, various types of intraoperative repair can minimize the risk of
postoperative CSF leak to a range of 8-10% (Gaynor et al., 2013). The risk of postoperative
CSF leak is further increased by high flow CSF leak and by patient factors, in particular
obesity (Dlouhy et al., 2012). The risk of postoperative leak can be decreased further by
prophylactic placement of an invasive lumbar spinal drain after surgery (Patel et al., 2013),
but lumbar drains are associated with various disadvantages including discomfort, prolonged
hospital stay, and risk of infection, bleeding and other serious complications. Less risky
strategies for minimizing the risk of postoperative CSF leak in this patient population are
needed.

Acetazolamide (Diamox) is a carbonic anhydrase inhibitor that decreases production of CSF by
reducing sodium transport across the choroid plexus epithelium in the ventricles of the
brain. Acetazolamide can be given orally or by IV, and is widely used clinically for
decreasing CSF production in patients with idiopathic intracranial hypertension (pseudotumor
cerebri) and active CSF leak after surgery or head trauma. In one small pilot study,
Acetazolamide was used successfully in lieu of lumbar spinal drainage in patients undergoing
elective thoracic aortic aneurysm repair. Acetazolamide has a well- established safety
profile and rapid onset of action (4 hours when given IV, 12 hours when given orally). We
plan a prospective pilot study of Diamox intended to assess the safety and possible
effectiveness of Acetazolamide for the prevention of postoperative CSF leak in high-risk
patients undergoing transsphenoidal surgery for removal of sellar and parasellar tumors.

Inclusion Criteria:

- Elective transsphenoidal resection of a tumor expected to result in an intraoperative
high flow CSF leak; such tumors include craniopharyngioma, meningioma, and Rathke
cleft cyst.

- Elective transsphenoidal resection of a pituitary adenoma, with BMI >25, or with
observed low or high flow CSF leak during surgery, conferring an elevated risk of
postoperative CSF leak.

- Patients who voluntarily sign Informed Consent

Exclusion Criteria:

- Adults unable to consent

- Individuals who are not yet adults (infants, children, teenagers)

- Pregnant women

- Prisoners

- Patients with prior adverse reactions to acetazolamide or who are taking aspirin
concomitantly (which may increase the risk of adverse reactions to acetazolamide)

- Patients with moderate to severe chronic obstructive pulmonary disease (which may
increase the risk of adverse effects of acetazolamide)