Journal of Anesthesia and SurgeryJournal of Anesthesia and SurgeryJournal of Anesthesia and SurgeryJournal of Anesthesia and Surgery2377-1364Ommega Online PublishersNew Jersey, USA199710.15436/2377-1364.18.1997Research ArticleNeutrophil to Lymphocyte Ratio as a Prognostic Biomarker for Morbidity and Mortality in Patients Undergoing Benign Surgery: A Systematic ReviewNeutrophil to Lymphocyte Ratio as a Prognostic Biomarker for Morbidity and Mortality in Patients Undergoing Benign Surgery: A Systematic ReviewCamilla GodthaabCenter for Surgical Science Department of Surgery Zealand University Hospital Lykkeb aelig kvej 1 K oslash geEditor* E-mail: camilla_godthaab@hotmail.com
The authors have declared that no competing interests exist.
20181411201852JAS-18-RW-199706102018111020182018Creative Commons Attribution LicenseThis is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Background Neutrophil to lymphocyte ratio NLR reflects the degree of systemic inflammation Several clinical trials have shown that a high preoperative NLR predicts morbidity and mortality after surgery for malignant disease Whether preoperative NLR predicts morbidity and mortality after benign surgery is uncertain The aim of this systematic review was to investigate whether preoperative NLR predicts postoperative morbidity and mortality after benign surgery Method A systematic review was performed according to Preferred Reporting Items for Systematic Reviews and Meta-analyses The population was limited to adults undergoing benign surgery The search was performed in PubMed Scopus Embase and the Cochrane Library Risk of bias was evaluated with ACROBAT-NRSI Results 25 clinical observational studies with a total of 10 015 patients were included Types of surgery were cardiac surgery N 11 vascular surgery N 6 and non-cardiac non-vascular surgery N 8 The studies in cardiac and vascular surgery showed associations between preoperative NLR and postoperative mortality 11 out of 13 studies in cardiac and vascular surgery showed a significant association between NLR and postoperative morbidity In orthopaedic surgery NLR predicted troponin elevation after hip surgery and postoperative infections after knee surgery while no association was shown between preoperative NLR and postoperative complications in patients amputated due to diabetic foot ulcers NLR predicted postoperative complications after prosthesis implantation and bowel resection NLR did not predict the risk of postoperative complications after abdominal and miscellaneous non-cardiac surgery Conclusion In cardiac and vascular surgery a high preoperative NLR was significantly associated with postoperative morbidity and mortality The predictive value of NLR in non-cardiac non-vascular surgery was unclear and should be investigated in larger clinical studies 10