title: Coronary artery bypass graft surgery depletes plasma thiamine levels.
abstract: OBJECTIVE
  Thiamine is an essential component of cellular metabolism, and lack of this vitamin results in a potentially life-threatening biochemical lesion. The stress of surgery and critical disease depletes electrolytes, minerals, and essential biochemical substrates. We hypothesized that critical illness (represented by major surgery) would result in decreased thiamine levels over time.
  
  
  METHODS
  We performed a prospective, observational study of serial thiamine levels of 15 patients who underwent non-emergent coronary artery bypass graft surgery. The primary endpoint was change in thiamine levels from before to immediately after surgery. Secondary endpoints included change in thiamine levels from presurgical to 6- and 24-h time points.
  
  
  RESULTS
  Of the 15 study patients, 1 did not have a plasma thiamine measurement at time 0 because of laboratory error and could not be accounted for in paired comparisons over time. Plasma thiamine levels decreased significantly from before to after coronary artery bypass grafting (P=0.0004). In addition, there was a statistically significant decrease in thiamine levels from before surgery to 24h (P=0.003).
  
  
  CONCLUSIONS
  Our data suggest that major surgery (as a surrogate for the stress of critical illness) depletes thiamine levels; further study is needed to determine whether routine replacement of thiamine in the critically ill is warranted.
authors.affiliation: Department of Emergency Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA. mdonnino@bidmc.harvard.edu
authors.forename: Michael W
authors.initials: MW
authors.lastname: Donnino
authors.forename: Michael N
authors.initials: MN
authors.lastname: Cocchi
authors.forename: Howard
authors.initials: H
authors.lastname: Smithline
authors.forename: Erin
authors.initials: E
authors.lastname: Carney
authors.forename: Peter P
authors.initials: PP
authors.lastname: Chou
authors.forename: Justin
authors.initials: J
authors.lastname: Salciccioli
authors.forename: Justin
authors.initials: J
authors.lastname: Salciccoli
mesh_terms: D000368:Aged; D001026:Coronary Artery Bypass; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D019370:Observation; D011183:Postoperative Complications / Q000097:blood*; D011446:Prospective Studies; D013831:Thiamine / Q000097:blood*; D013997:Time Factors
chemical_list: D013831:Thiamine