title: Factors related to postoperative delirium in patients with lower limb ischaemia: a prospective cohort study.
abstract: OBJECTIVE
  To preoperatively determine candidates at definitive risk of postoperative delirium (POD), we identified relevant factors in patients with arteriosclerosis obliterans who underwent bypass surgery.
  
  
  METHODS
  A prospective cohort study.
  
  
  METHODS
  299 patients (age ≥ 60 years) who underwent bypasses in 1995-2006 were enrolled. Cognitive impairment was assessed by the Revised Hasegawa Dementia Scale, the Confusion Assessment Method was also used, and severity was graded as Grade I-III (mild to severe) based on the Delirium Rating Scale. All patients were followed for 3 years.
  
  
  RESULTS
  POD occurred in 88 patients (29%), with a median age of 75 (10) years (IQR). Onset was 2 (1) days postoperatively, and a duration of 2 (2) days was observed. POD was hyperactive in 89% and was Grade I, II, and III in 11%, 68%, and 21% respectively. Multiple logistic regression analysis identified the following risk factors for POD: age ≥ 72 years (<0.0001), end-stage renal failure (0.001), multiple occlusive lesions (<0.0001), cognitive impairment (0.003), and critical limb ischaemia (0.034). The 3-year survival rate was similar when comparing POD and non-POD patients (84% vs. 88%, NS).
  
  
  CONCLUSIONS
  This study identified 5 risk factors for POD in patients undergoing bypasses for limb ischaemia. Long-term outcomes were similar when comparing the patients who experienced POD with those who did not.
authors.affiliation: Asahikawa College, Hokkaido Educational University, Asahikawa, Japan. sasajima@asahikawa-med.ac.jp
authors.forename: Y
authors.initials: Y
authors.lastname: Sasajima
authors.forename: T
authors.initials: T
authors.lastname: Sasajima
authors.forename: N
authors.initials: N
authors.lastname: Azuma
authors.forename: K
authors.initials: K
authors.lastname: Akazawa
authors.forename: Y
authors.initials: Y
authors.lastname: Saito
authors.forename: M
authors.initials: M
authors.lastname: Inaba
authors.forename: H
authors.initials: H
authors.lastname: Uchida
mesh_terms: D000367:Age Factors; D000368:Aged; D001162:Arteriosclerosis Obliterans / Q000601:surgery*; D003693:Delirium / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007564:Japan / Q000453:epidemiology; D007866:Leg / Q000098:blood supply*; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D011379:Prognosis; D011446:Prospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D013997:Time Factors; D014656:Vascular Surgical Procedures