Abbreviations
American Socity of Anesthesiology physical status classificationConfident intervalColorectal cancerInstitutional Review Board.Interquartil rangeModified Observer’s Assessment of Altreness/ Sedation ScaleNon steroidal antiinflammatory drugsSeretonin-norepinephrine reuptake inhibitor.Patient controlled analgesiaPostanesthesia care unitThe Quality of Recovery − 40 scoring systemVisual Analog Scale5 Hydroxy-tryptamine