title: Neutrophil lymphocyte ratio in outcome prediction after emergency abdominal surgery in the elderly.
abstract: BACKGROUND
  Accurate prediction of outcome after emergency surgery in elderly patients may assist decision-making. Many scoring systems require post-operative data (e.g. P-POSSUM) whilst others have failed to gain widespread use. Recent reports suggest that C-reactive protein (CRP) and the neutrophil lymphocyte (N/L ratio) ratio may predict surgical outcome.
  
  
  METHODS
  A retrospective review of all patients aged 80 years or over undergoing emergency abdominal surgery over a 22 month period was conducted. Outcome and clinical data were collected. Univariate, multivariate and recursive analyses were performed for outcome at 30 days, 6 months and 12 months. Findings were validated in a second independent dataset.
  
  
  RESULTS
  88 patients were included in the test dataset, median age 84 years. 30-day mortality was 31%, 6-month mortality 43% and 12-month mortality 50%. Univariate analysis identified N/L ratio, CRP, midline laparotomy, and surgical risk score to predict outcome at each time point. Recursive analysis showed, N/L ratio ≥22 best predicted 30-day outcome (p=0.0018). Multivariate analysis identified N/L ratio to be an independent predictor of 30-day outcome (p=0.004) yet CRP did not predict outcome at any time point. An independent dataset (n=84) confirmed N/L ratio to be a prognostic factor at 30 days (p=0.001), 6 months (p<0.001) and 12 months (p=0.001).
  
  
  CONCLUSIONS
  N/L ratio is an easily calculable pre-operative measure that may have utility in the prediction of outcome after emergency abdominal surgery in the elderly. Further work to validate this measure in a larger, prospective setting and determine the underlying mechanisms that mediate outcome are necessary.
authors.affiliation: Department of Colorectal Surgery, Southampton University Hospitals Trust, Southampton, SO16 6YD, UK.
authors.forename: P G
authors.initials: PG
authors.lastname: Vaughan-Shaw
authors.forename: J R E
authors.initials: JR
authors.lastname: Rees
authors.forename: A T
authors.initials: AT
authors.lastname: King
mesh_terms: D000006:Abdomen, Acute / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D000367:Age Factors; D000369:Aged, 80 and over; D004638:Emergency Treatment / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007813:Laparotomy; D007958:Leukocyte Count; D008214:Lymphocytes / Q000166:cytology*; D008297:Male; D009504:Neutrophils / Q000166:cytology*; D017063:Outcome Assessment, Health Care / Q000379:methods*; D011183:Postoperative Complications / Q000175:diagnosis / Q000453:epidemiology*; D011184:Postoperative Period; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D015996:Survival Rate / Q000639:trends; D006113:United Kingdom / Q000453:epidemiology