title: Early introduction of tolvaptan after cardiac surgery: a renal sparing strategy in the light of the renal resistive index measured by ultrasound.
abstract: BACKGROUND
  Renal failure is a serious complication after cardiac surgery, which can be caused by long-term intravenous (IV) loop diuretic use. Tolvaptan is an oral selective vasopressin-2 receptor antagonist used in patients irresponsive to loop diuretics. We investigated their renal perfusion changes using the resistive index (RI) postoperatively.
  
  
  METHODS
  Serial renal RI, echocardiography, and laboratory examinations from 14 patients requiring continuous postoperative IV loop diuretics were reviewed. Eight patients received tolvaptan (Group T) and six received oral loop diuretics before the discontinuation of IV loop diuretics (Group L). The 1(st) data were obtained between postoperative day 0 and 2, the 2(nd) when patients were still under IV loop diuretic treatment, the 3(rd) after the initiation of tolvaptan or oral loop diuretic, and the 4(th) after the discontinuation of IV diuretics.
  
  
  RESULTS
  The 2(nd) RI value was higher in Group T than Group L (0.77 ± 0.09 vs. 0.69 ± 0.01, p = 0.049) but significantly decreased after tolvaptan administration [0.77 ± 0.09 to 0.65 ± 0.05 (2(nd) to 3(rd)), to 0.62 ± 0.04 (to 4(th)), both p = 0.006], while no such changes were seen in Group L. The serum sodium and albumin levels, and echo-derived tricuspid annular plane systolic excursion increased only in Group T (134.1 ± 1.5 to 138.8 ± 3.2 mEq/L, 3.3 ± 0.3 to 3.7 ± 0.5 g/dL, 16.4 ± 3.6 to 19.7 ± 4.2 mm, all p <0.05). The duration of IV loop diuretics tended to be shorter in Group T than Group L (5.6 ± 1.6 vs. 8.7 ± 3.6 days, p = 0.051).
  
  
  CONCLUSIONS
  Administration of tolvaptan in patients undergoing cardiac surgery may improve their renal perfusion, as reflected by the renal RI measured using renal Doppler ultrasound.
authors.affiliation: Department of Cardiovascular Surgery, Juntendo University School of Medicine, 2-1-1, Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan. tokato@juntendo.ac.jp.
authors.forename: Tomoko S
authors.initials: TS
authors.lastname: Kato
authors.affiliation: Department of Cardiovascular Surgery, Juntendo University School of Medicine, 2-1-1, Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.
authors.forename: Shunya
authors.initials: S
authors.lastname: Ono
authors.affiliation: Department of Cardiovascular Surgery, Juntendo University School of Medicine, 2-1-1, Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.
authors.forename: Kan
authors.initials: K
authors.lastname: Kajimoto
authors.affiliation: Department of Cardiovascular Surgery, Juntendo University School of Medicine, 2-1-1, Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Kuwaki
authors.affiliation: Department of Cardiovascular Surgery, Juntendo University School of Medicine, 2-1-1, Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.
authors.forename: Taira
authors.initials: T
authors.lastname: Yamamoto
authors.affiliation: Department of Cardiovascular Surgery, Juntendo University School of Medicine, 2-1-1, Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Amano
mesh_terms: D065092:Antidiuretic Hormone Receptor Antagonists / Q000008:administration & dosage / Q000627:therapeutic use*; D001552:Benzazepines / Q000008:administration & dosage / Q000627:therapeutic use*; D013504:Cardiovascular Surgical Procedures; D015150:Echocardiography, Doppler; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000517:prevention & control*; D051437:Renal Insufficiency / Q000000981:diagnostic imaging / Q000517:prevention & control*; D012189:Retrospective Studies; D000077602:Tolvaptan; D016896:Treatment Outcome
chemical_list: D065092:Antidiuretic Hormone Receptor Antagonists; D001552:Benzazepines; D000077602:Tolvaptan