title: Novel application of acetazolamide to reduce cerebrospinal fluid production in patients undergoing thoracoabdominal aortic surgery.
abstract: OBJECTIVE
  Paraplegia is a rare but devastating complication, which may follow thoracoabdominal aortic surgery. Many adjuncts have been developed to reduce this risk including cerebrospinal fluid (CSF) drainage. Acetazolamide (carbonic anhydrase inhibitor) is a drug used to counteract mountain sickness and one of its effects is to reduce CSF production. Here, we report its first postoperative application in thoracoabdominal surgery with the aim of reducing cerebrospinal cord perfusion pressure and reducing risk of paraplegia.
  
  
  METHODS
  We retrospectively reviewed 6 patients who have been treated with this drug between 2011 and 2012 who were undergoing thoracoabdominal aortic surgery. Our indications were decided to include: (i) patients in whom a spinal drain could not be positioned; (ii) patients with blood-stained CSF; (iii) patients in whom the volume of CSF drained was outside guidelines; (iv) patients in whom CSF pressure was elevated; (v) patients with excessive vasopressor usage and (vi) patients with postoperative neurological dysfunction as measured by motor-evoked potentials or clinical examination. All were given 500 mg intravenous acetazolamide, not more than eight hourly, for a duration dependent on response.
  
  
  RESULTS
  In the 6 patients, 2 received a single dose of the drug and responded by an immediate drop in intracranial pressure (ICP) pressure. Of the 4 who received multiple doses of the drug, 1 had an immediate decline in ICP after each of the first six doses, while 3 had no discernable response.
  
  
  CONCLUSIONS
  This is the first report of the efficacy of acetazolamide in reducing CSF production and lowering ICP during thoracoabdominal aortic surgery. We believe that its use will be beneficial in the 6 patient groups described. Our experience suggests there are 'responders' and 'non-responders', the characteristics of whom are yet to be defined. Its efficacy in reducing not just CSF volume and ICP but also clinically relevant morbidity such as paraplegia, is the subject of a planned randomized controlled trial. This report serves to raise awareness of the possible efficacy of this drug when normal management strategies are limited or exhausted.
authors.affiliation: Institute of Cardiovascular Medicine and Science, Thoracic Aortic Aneurysm Service, Liverpool Heart and Chest Hospital, Liverpool, UK.
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Jafarzadeh
authors.forename: Mark L
authors.initials: ML
authors.lastname: Field
authors.forename: Deborah K
authors.initials: DK
authors.lastname: Harrington
authors.forename: Manoj
authors.initials: M
authors.lastname: Kuduvalli
authors.forename: Aung
authors.initials: A
authors.lastname: Oo
authors.forename: Jonathan
authors.initials: J
authors.lastname: Kendall
authors.forename: Mike
authors.initials: M
authors.lastname: Desmond
authors.forename: Keith
authors.initials: K
authors.lastname: Mills
mesh_terms: D000086:Acetazolamide / Q000627:therapeutic use*; D000328:Adult; D000368:Aged; D001012:Aorta, Abdominal / Q000601:surgery*; D001013:Aorta, Thoracic / Q000601:surgery*; D002257:Carbonic Anhydrase Inhibitors / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D019586:Intracranial Hypertension / Q000134:cerebrospinal fluid / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control*; D007427:Intracranial Pressure / Q000187:drug effects*; D008297:Male; D008875:Middle Aged; D010264:Paraplegia / Q000134:cerebrospinal fluid / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control*; D012189:Retrospective Studies; D013997:Time Factors; D016896:Treatment Outcome; D014656:Vascular Surgical Procedures / Q000009:adverse effects*
chemical_list: D002257:Carbonic Anhydrase Inhibitors; D000086:Acetazolamide
keywords: Acetazolamide; Paraplegia; Thoracoabdominal surgery