Immune-Mediatory Response of Intravenous Ketamine Versus Propofol for Elective Open Colectomy: A Prospective Randomised Study

BackgroundSurgical stress response is a host defense mechanism against tissue injury but its exaggeration can cause postoperative morbidity.Anaesthetics can modulate this response with variable degrees.Therefore, this study was conducted to compare the immune-modulatory effects of intraoperative intravenous infusion of propofol versus ketamine. Patients and MethodsForty patients scheduled for open colectomy under inhalational based general anaesthesia were included.They were allocated randomly into Group P (n= 20) which was given intravenous propofol 1% at a subanaesthetic infusion dose of 17g/kg/min, and group K (n= 20) which was given Ketamine 0.3% (150mg/50ml) at a subanaesthetic infusion dose of 5g/kg/min.The primary outcome was the post-infusion serum IL-6 2 hours after the start of infusion.The secondary outcomes were IL-1, TLC, absolute neutrophil count and N/L ratio, glucose level, CRP level, postoperative agitation, mean NRS score for pain at rest and movement during the first day, and time to the resumption of GIT function. ResultsPost-infusion serum IL-6 after 2 hours was significantly higher in group K (P<0.001).Additionally, Serum IL-1, glucose and CRP levels were significantly higher in Group K. Postoperative agitation score was significantly higher (P<0.001) and mean postoperative pain score during rest was significantly lower (P 0.003) in group K.Other outcomes were comparable between both groups. ConclusionsPropofol is more effective than ketamine in reducing the surgical stress response as noted by decreased IL-6 and IL-1, blood glucose, and CRP when compared with ketamine.