title: Intravenous diltiazem and acute renal failure after cardiac operations.
abstract: BACKGROUND
  Perioperative administration of intravenous diltiazem to patients undergoing cardiac procedures has been shown to decrease the incidence of ischemia and arrhythmias. However, after adopting this practice in our cardiac surgery program, we perceived an increased incidence of postoperative renal dysfunction.
  
  
  METHODS
  A directed record review of postoperative renal function was conducted for consecutive patients undergoing cardiac operation for the time periods before and after adoption of prophylactic intravenous diltiazem (0.1 mg.kg-1.h-1 for 24 hours). The two groups were compared using chi 2 and two-sample t tests. The risk of development of postoperative renal failure was modeled with logistic regression.
  
  
  RESULTS
  Diltiazem-treated patients (n = 271) were similar to the control patients (n = 143) in terms of age (64 versus 61 years; p = 0.14), ejection fraction (0.46 versus 0.47; p = 0.61), baseline serum creatinine level (1.2 versus 1.1 mg/dL; p = 0.27), prevalence of comorbid conditions, and surgical characteristics. The prevalence of left main coronary artery disease was lower in the diltiazem group than the control group (39% versus 52%; p = 0.01). During the 7-day postoperative period, the average peak serum creatinine level was higher in the diltiazem group (1.7 +/- 0.9 mg/dL; mean +/- 1 standard deviation) than the control group (1.5 +/- 0.5 mg/dL; p = 0.003). The incidence of acute renal failure requiring dialysis was 4.4% in the diltiazem group versus 0.7% in the control group (p = 0.04). There was no difference in length of hospitalization or mortality. The risk of acute renal failure was strongly associated with intravenous diltiazem (adjusted odds ratio [AOR] 6.3; p = 0.08), age (AOR 2.5 per 10 years; p = 0.07), baseline serum creatinine (AOR 4.8 per 1 mg/dL; p = 0.02), the presence of left main coronary disease (AOR 5.3; p = 0.02), and the presence of cerebrovascular disease (AOR 4.5; p = 0.05).
  
  
  CONCLUSIONS
  Our retrospective analysis suggests that prophylactic use of intravenous diltiazem in patients undergoing cardiac operations was associated with increased renal dysfunction. Further studies of the risk and benefits of intravenous diltiazem in this setting should be undertaken.
authors.affiliation: Nephrology Section, Veterans Affairs Medical Center, Ann Arbor, Michigan 48105, USA.
authors.forename: E W
authors.initials: EW
authors.lastname: Young
authors.forename: A
authors.initials: A
authors.lastname: Diab
authors.forename: M M
authors.initials: MM
authors.lastname: Kirsh
mesh_terms: D058186:Acute Kidney Injury / Q000209:etiology* / Q000628:therapy; D000367:Age Factors; D001145:Arrhythmias, Cardiac / Q000517:prevention & control; D002121:Calcium Channel Blockers / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D002561:Cerebrovascular Disorders / Q000150:complications; D016009:Chi-Square Distribution; D001026:Coronary Artery Bypass / Q000009:adverse effects; D003327:Coronary Disease / Q000601:surgery; D003404:Creatinine / Q000097:blood; D004110:Diltiazem / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D015994:Incidence; D007262:Infusions, Intravenous; D007430:Intraoperative Care; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000517:prevention & control; D016017:Odds Ratio; D015995:Prevalence; D006435:Renal Dialysis; D012189:Retrospective Studies; D012307:Risk Factors; D013318:Stroke Volume; D014665:Vasodilator Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*
chemical_list: D002121:Calcium Channel Blockers; D014665:Vasodilator Agents; D003404:Creatinine; D004110:Diltiazem