Identification of pre-operative of risk factors associated with persistent post-operative pain by self-reporting tools in lower limb amputee patients - A feasibility study.

Aims The incidence of persistent post-operative pain (PPP) is 30-85% in lower limb amputee (LLA) patients and identification of preoperative risk factors are warranted. Preoperative levels of anxiety, depression, pain catastrophizing, neuropathic pain and severe preoperative pain have previously been linked with PPP but such screening tools are not used in the clinical hospital setting. The aim of this study was to assess feasibility of using questionnaires for anxiety, depression, pain catastrophizing, neuropathic pain and preoperative pain levels in a clinical preoperative setting. Methods Patients scheduled for non-traumatic amputation of the lower leg or femur were recruited from three Danish hospitals. Exclusion criteria were surgery 4-weeks prior to LLA, same leg re-amputation, or inability to participate. Pre-operative values of anxiety, depression and catastrophizing were assessed using the Hospital Anxiety (A) and Depression(D) Scale (HADS) (cutoff: 8) and Pain Catastrophizing Scale (PCS) (cutoff =32). Neuropathic pain was assessed preoperatively using Pain-Detect-Questionnaire (PD-Q) (cutoff: 19). The maximum preoperative pain intensity was assessed using the Numeric Rating Scale (NRS; 0: no pain and 10: worst imaginable pain). Scores are presented as median values with interquartile range (Q1-Q3). Results Eight of 18 patients (5 females) completed this pilot study: median age 71 (range 56-83), 6 femur and two lower leg amputees. Nine of ten excluded patients were unable to complete the questionnaires and one patient was operated acutely. Median pre-operative HADS-D and -A scores were 7 (3-9, 50% ≥ cutoff) and 4 (1-8, 25% ≥ cutoff), pre-operative PCS score was 24 (18-28, 13% ≥ cutoff), pre-operative PD-Q score was 16 (8-22, 50% ≥ cutoff) and NRS score was 9.5 (8-10). Conclusions This study indicates that it is possible to implement preoperative questionnaires in a clinical setting. However, more than 50% of the patients are unable to complete the questionnaires.