Abstract
"The thesis is organised in three chapters. The first chapter analyses postoperative morbidity and the mechanisms of action of ischaemic preconditioning (RIPC). The second chapter is a systematic review on the use of RIPC in non-cardiac non-vascular (NCNV) surgery and the third chapter describes a randomised controlled trial (RCT) in NCNV surgery.
Remote ischaemic preconditioning (RIPC) has been investigated as a simple intervention to potentially reduce postoperative morbidity. A systematic review of the published literature identified 36 RCTs investigating the effect of RIPC in NCNV surgery. The meta-analysis concluded that RIPC was associated with positive outcomes including lower postoperative serum creatinine, lower neutrophil gelatinase-associated lipocalin, improved oxygenation and shorter length of hospital stay; however, the results were limited by considerable heterogeneity and therefore further evidence is required.
Subsequently, a double blinded pilot RCT was conducted that included 47 patients undergoing surgery for intra-abdominal (gynaecological, pancreatic and colorectal) malignancies. The patients were randomized into intervention (RIPC) or control group. The primary outcome was feasibility and the main secondary outcome was postoperative morbidity including serum troponin and the urinary biomarkers tissue inhibitor of metalloproteinases-2 and insulin-like growth factor-binding protein 7 (TIMP-2*IGFBP-7).
The recruitment target was reached and the protocol procedures were followed. The intervention group developed fewer surgical complications at 30 days (4.5% vs. 33%), 90 days (9.5% vs. 35%) and 6 months (11% vs. 41%), adjusted P 0.033, 0.044 and 0.044 respectively. RIPC was a significant independent variable for lower overall postoperative morbidity survey (POMS) score, OR 0.79 (95% CI 0.63 to 0.99) and fewer complications at 6 months including pulmonary OR 0.2 (95% CI 0.03 to 0.92), surgical OR 0.12 (95% CI 0.007 to 0.89) and overall complications, OR 0.18 (95% CI 0.03 to 0.74).
Our study showed that RIPC may improve outcomes following intra-abdominal cancer surgery and that a larger trial would be feasible. "