title: Comparing the DN4 tool with the IASP grading system for chronic neuropathic pain screening after breast tumor resection with and without paravertebral blocks: a prospective 6-month validation study.
abstract: Investigating protective strategies against chronic neuropathic pain (CNP) after breast cancer surgery entails using valid screening tools. The DN4 (Douleur Neuropathique en 4 questions) is 1 tool that offers important research advantages. This prospective 6-month follow-up study seeks to validate the DN4 and assess its responsiveness in screening for CNP that satisfies the International Association for the Study of Pain (IASP) definition and fulfills its grading system criteria after breast tumor resection with and without paravertebral blocks (PVBs). We randomized 66 females to standardized general anesthesia and sham subcutaneous injections, or PVB and total intravenous anesthesia. The 6-month CNP risk was assessed using the IASP grading system and the DN4 screening tools. We evaluated the DN4 sensitivity, specificity, and responsiveness in capturing the impact of PVB on the CNP risk relative to the IASP grading system. Data from 64 patients showed similar demographic characteristics in both groups. Twenty patients in both groups met the grading system CNP criteria; among these, 18 patients also met the DN4 CNP criteria. Furthermore, 15 patients in both groups did not meet the grading system CNP criteria; among these, 9 patients also did not meet the DN4 CNP criteria. Therefore, the sensitivity and specificity of the DN4 were estimated at 90% and 60%, respectively. Both screening tools suggested that PVB reduced the 6-month CNP risk. Our results suggest that the DN4 can reliably identify CNP at 6 months after breast tumor resection and detect the preincisional PVB effect on the risk of developing such pain.
authors.affiliation: Department of Anesthesia, University of Toronto, Toronto, Ontario, Canada Department of Anesthesia, St. Michael's Hospital, Toronto, Ontario, Canada Keenan Research Centre, Li Ka Shing Knowledge Institute, Toronto, Ontario, Canada Department of Anesthesia, Women's College Hospital, Toronto, Ontario, Canada Department of Surgery, Women's College Hospital, University of Toronto, Toronto, Ontario, Canada Department of Anesthesia, Toronto Western Hospital, University Health Network, Toronto, Ontario, Canada.
authors.forename: Faraj W
authors.initials: FW
authors.lastname: Abdallah
authors.forename: Pamela J
authors.initials: PJ
authors.lastname: Morgan
authors.forename: Tulin
authors.initials: T
authors.lastname: Cil
authors.forename: Jaime M
authors.initials: JM
authors.lastname: Escallon
authors.forename: John L
authors.initials: JL
authors.lastname: Semple
authors.forename: Vincent W
authors.initials: VW
authors.lastname: Chan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000601:surgery; D005260:Female; D006801:Humans; D006993:Hypnotics and Sedatives / Q000008:administration & dosage*; D015412:Mastectomy, Segmental / Q000009:adverse effects; D008875:Middle Aged; D009437:Neuralgia / Q000175:diagnosis / Q000209:etiology / Q000517:prevention & control; D010147:Pain Measurement / Q000145:classification / Q000379:methods*; D010149:Postoperative Pain / Q000209:etiology*; D015742:Propofol / Q000008:administration & dosage*; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D013116:Spinal Cord / Q000187:drug effects* / Q000502:physiology; D055815:Young Adult
chemical_list: D006993:Hypnotics and Sedatives; D015742:Propofol