title: Greater intravenous fluid volumes are associated with prolonged recovery after colorectal surgery: a retrospective cohort study.
abstract: BACKGROUND
  We carried out a retrospective assessment of whether perioperative fluid volume was associated with length of hospital stay (LOS) after colorectal surgery.
  
  
  METHODS
  A single-centre chart review was conducted on colorectal surgeries that took place between January 2008 and December 2013. The primary outcome was LOS, with prolonged LOS defined as greater than median LOS. Secondary outcomes included postoperative pulmonary oedema, acute renal failure, myocardial infarction, and mortality. Univariate analysis, multivariable logistic regression, and quantile regression analyses were conducted to examine the association between perioperative fluid volume and prolonged LOS.
  
  
  RESULTS
  Of the 1242 procedures, 57% were elective, 62% oncological, and 31% laparoscopic. The median LOS was 8.2 days (interquartile range 5.2, 14.7). Patients received 3.2 (sd 1.5) litres of fluid in the perioperative period (operating and recovery rooms), predominantly crystalloid. The volume (in litres) of perioperative fluid was independently associated with prolonged LOS (odds ratio 1.23, 95% confidence interval 1.10-1.36, P<0.01). This association persisted across the spectrum of definitions for prolonged LOS (10th-90th percentile). Logistic regression analysis also revealed that prolonged LOS was associated with age >65 yr, Charlson Co-morbidity Index ≥3, use of colloids, emergent surgery, estimated blood loss >200 ml, preoperative anaemia, erythrocyte transfusion, open surgeries, and surgical duration >4 h (C-statistic=0.79, Hosmer-Lemeshow=0.36).
  
  
  CONCLUSIONS
  Greater perioperative fluid volume was independently associated with prolonged duration of recovery across a spectrum of surgical risk profiles. Fluid restriction should be considered a part of the care package in enhanced recovery after surgery programmes for colorectal surgery.
authors.affiliation: University of Toronto, Faculty of Medicine, Toronto, Ontario, Canada Department of Anesthesia and Pain Management, Toronto General Hospital, University Health Network, Toronto, Ontario, Canada.
authors.forename: Z
authors.initials: Z
authors.lastname: Aga
authors.affiliation: Department of Anesthesia and Pain Management, Toronto General Hospital, University Health Network, Toronto, Ontario, Canada.
authors.forename: M
authors.initials: M
authors.lastname: Machina
authors.affiliation: Department of Anesthesia and Pain Management, Toronto General Hospital, University Health Network, Toronto, Ontario, Canada Department of Anesthesia, University of Toronto, Toronto, Ontario, Canada stuart.mccluskey@uhn.ca.
authors.forename: S A
authors.initials: SA
authors.lastname: McCluskey
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000762:Anesthesia Recovery Period; D016063:Blood Loss, Surgical; D015331:Cohort Studies; D003107:Colorectal Surgery / Q000379:methods*; D000077324:Crystalloid Solutions; D005260:Female; D005440:Fluid Therapy / Q000009:adverse effects*; D006801:Humans; D007552:Isotonic Solutions; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D019990:Perioperative Care; D010952:Plasma Substitutes; D011183:Postoperative Complications / Q000453:epidemiology / Q000401:mortality; D012189:Retrospective Studies; D012307:Risk Factors
chemical_list: D000077324:Crystalloid Solutions; D007552:Isotonic Solutions; D010952:Plasma Substitutes
keywords: colorectal surgery; fluid therapy; length of stay; perioperative care