title: Left renal vein division during open surgery of abdominal aortic disease: a propensity score-matched case-control study.
abstract: OBJECTIVE
  To investigate the impact of left renal vein division (LRVD) on the postoperative renal function of abdominal aortic aneurysm (AAA) or aortic occlusive disease (AOD).
  
  
  METHODS
  Between January 2000 and January 2012, 238 patients, including 179 AAAs and 59 AODs underwent open surgery in our institution (patients who required suprarenal aortic clamping were excluded). 49 patients (38 AAAs, 11 AODs) required LRVD during the operation. Patients in the LRVD and non-LRVD groups were matched using propensity score method in a 1:2 ratio. Pre- and postoperative renal function, major complications, in-hospital mortality and long-term renal function were compared. Late survival rate was estimated using the Kaplan-Meier method.
  
  
  RESULTS
  Overall, the LRVD group had a significantly higher male/female ratio (39/10 vs.122/67, p = .045), higher ruptured AAA ratio (36.7% vs. 20.1%, p = .014), higher American Society of Anesthesiologists (ASA) classification 3 (53.1% vs. 30.2%, p = .003), higher co-morbidities of coronary artery disease (51.0% vs. 33.3%, p = .022), higher preoperative shock (22.4% vs. 8.5%, p = .006) and longer operative time (164.2 ± 43 vs. 150.1 ± 41 min, p = .035). With propensity score matching (PSM), 48 patients in the LRVD group and 96 in the non-LRVD group were enrolled in this study. The baseline characteristics were well balanced in the groups (p < .05) after PSM. There were no statistically significant differences in preoperative glomerular filtration rate (GFR, expressed as mL/min/1.73 m(2)) (62.0 ± 13.1 vs. 62.9 ± 12.9, p = .695), and postoperative GFR on day 1 (60.3 ± 13.7 vs. 61.3 ± 13.1, p = .671), day 3 (54.6 ± 16.8 vs. 58.8 ± 14.3, p = .120), day 7 (62.1 ± 16.8 vs. 63.7 ± 13.4 p = .537) and in the long term (>12 months) (62.4 ± 14.0 vs. 64.7 ± 11.8 p = .302). There were no statistically significant differences in in-hospital mortality (6.3% vs. 9.2%, p = .522) and late survival rate estimated by the Kaplan-Meier method (p = .96).
  
  
  CONCLUSIONS
  LRVD may be a safe maneuver during abdominal aortic surgery as it did not increase the risks of early or late mortality and morbidity.
authors.affiliation: Division of Vascular and Thyroid Surgery, First Hospital of China Medical University, China.
authors.forename: L
authors.initials: L
authors.lastname: Wang
authors.forename: S J
authors.initials: SJ
authors.lastname: Xin
authors.forename: Z
authors.initials: Z
authors.lastname: Song
authors.forename: J
authors.initials: J
authors.lastname: Zhang
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001012:Aorta, Abdominal / Q000601:surgery*; D001018:Aortic Diseases / Q000401:mortality / Q000601:surgery*; D015897:Comorbidity; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D057216:Propensity Score; D012082:Renal Veins / Q000601:surgery*; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012737:Sex Factors; D013997:Time Factors; D016896:Treatment Outcome; D014656:Vascular Surgical Procedures / Q000009:adverse effects / Q000379:methods* / Q000401:mortality
keywords: Aortic surgery; Left renal vein; Renal function