Patrice Forget1, Juan Cata2. 1. Vrije Universiteit Brussel (VUB), Universitair Ziekenhuis Brussel (UZ Brussel), Anesthesiology and Perioperative Medicine Departement, Laarbeeklaan 101, 1090 Brussels, Belgium. Electronic address: forgetpatrice@yahoo.fr. 2. Department of Anesthesiology, MD Anderson Cancer Center, Houston, TX, USA; Anesthesiology and Surgical Oncology Research Group, Houston, TX, USA.
Abstract
INTRODUCTION: The role of ketamine and magnesium in improving postoperative pain and diminish opioid consumption has been largely described. Synthetic opioids are known to provide hemodynamic stability when given for major noncardiac surgery. Definitive evidence on the role of ketamine and/or magnesium on intraoperative hemodynamic control would support their potential as alternatives to opioids during surgery. METHODS: The available literature published on PubMed/Medline and EMBASE was reviewed systematically to perform meta-analyses of randomized controlled trials (RCTs) assessing the effect of ketamine and/or magnesium on hemodynamic response to surgery as the primary outcome. RESULTS: From 352 studies, we identified 19 RCTs, and after exclusion of eight studies (seven for inappropriate data reporting and one in non-English language), we analyzed 11 RCTs (five for ketamine and six for magnesium sulfate) including, in total, 371 patients, of whom 94 vs. 95 received ketamine vs. placebo and 147 vs. 145 received magnesium vs. placebo, respectively. Results show that in quantitative analyses, ketamine vs. placebo did not show a significant effect on heart rate (+0.71 bpm; 95% CI [-1.52 to +2.93], P = 0.53) but significantly reduced variability of blood pressure (-8.4 mmHg; 95% CI [-15.1 to -1.8], P = 0.0005). In contrast, magnesium vs. placebo reduced variability of heart rate (-3.7 bpm; 95% CI [-6.5 to 0.9], P = 0.01) without a significant effect on systemic blood pressure (+4.2 mmHg; 95% CI [-3.6 to +12.03], P = 0.29). CONCLUSION: In conclusion, these meta-analyses of nine trials confirm that ketamine and magnesium, differently but consistently, reduce hemodynamic variability during surgery and may be seen as complementary not only for pain control but also to provide stable anesthesia. This study supports the use of those drugs to control the sympathetic response to surgery in the context of opioid-free anesthesia.
INTRODUCTION: The role of ketamine and magnesium in improving postoperative pain and diminish opioid consumption has been largely described. Synthetic opioids are known to provide hemodynamic stability when given for major noncardiac surgery. Definitive evidence on the role of ketamine and/or magnesium on intraoperative hemodynamic control would support their potential as alternatives to opioids during surgery. METHODS: The available literature published on PubMed/Medline and EMBASE was reviewed systematically to perform meta-analyses of randomized controlled trials (RCTs) assessing the effect of ketamine and/or magnesium on hemodynamic response to surgery as the primary outcome. RESULTS: From 352 studies, we identified 19 RCTs, and after exclusion of eight studies (seven for inappropriate data reporting and one in non-English language), we analyzed 11 RCTs (five for ketamine and six for magnesium sulfate) including, in total, 371 patients, of whom 94 vs. 95 received ketamine vs. placebo and 147 vs. 145 received magnesium vs. placebo, respectively. Results show that in quantitative analyses, ketamine vs. placebo did not show a significant effect on heart rate (+0.71 bpm; 95% CI [-1.52 to +2.93], P = 0.53) but significantly reduced variability of blood pressure (-8.4 mmHg; 95% CI [-15.1 to -1.8], P = 0.0005). In contrast, magnesium vs. placebo reduced variability of heart rate (-3.7 bpm; 95% CI [-6.5 to 0.9], P = 0.01) without a significant effect on systemic blood pressure (+4.2 mmHg; 95% CI [-3.6 to +12.03], P = 0.29). CONCLUSION: In conclusion, these meta-analyses of nine trials confirm that ketamine and magnesium, differently but consistently, reduce hemodynamic variability during surgery and may be seen as complementary not only for pain control but also to provide stable anesthesia. This study supports the use of those drugs to control the sympathetic response to surgery in the context of opioid-free anesthesia.