The Effect of Ketamine on Acute and Chronic Wound Pain in Patients Undergoing Breast Surgery: A Meta-Analysis and Systematic Review.

INTRODUCTION: Perioperative use of ketamine has been discussed widely in many kinds of surgery. The aim of our study was to evaluate the short-term and long-term benefits and safety of ketamine after breast surgery. METHOD: We performed a quantitative systematic review. We included randomized controlled trials that compared intravenous administration of ketamine to a placebo control group, or compared bupivacaine in combination with ketamine to bupivacaine alone in thoracic paravertebral blocks or pectoral blocks among patients undergoing breast surgery. The primary outcome was postoperative pain intensity. Secondary outcomes included cumulative opioid consumption during the 0- to 24-hour postoperative period, the effect on postmastectomy pain syndrome, the effect on postoperative depression, and the adverse events associated with the use of ketamine. RESULTS: Thirteen randomized controlled trials with 1,182 patients were included for analysis. Compared with placebo, intravenous ketamine was effective in reducing wound pain intensity during the first 6 hours after surgery (weighted mean difference [WMD] -0.83; 95% confidence interval [CI] -1.65, -0.01; P = 0.048) and during the first 24 hours after surgery (WMD -0.65; 95% CI -0.95, -0.35; P < 0.001), and in decreasing opioid consumption (WMD -4.14; 95% CI -8.00, -0.29; P = 0.035) during the first 24 hours after surgery, without increasing the risks for gastrointestinal and central nervous system adverse events. Adding ketamine to bupivacaine in thoracic paravertebral blocks was also effective in reducing postoperative wound pain during the first 6 hours after surgery (WMD -0.59; 95% CI, -1.06, -0.12; P = 0.014) and during the first 24 hours after surgery (WMD -0.90; 95% CI -1.27, -0.53; P < 0.001), and in decreasing opioid consumption (WMD - 4.59; 95% CI -5.76, -3.42; P < 0.001) during the first 24 hours after surgery. Perioperative use of ketamine was associated with improved postoperative depression symptoms (standardized mean difference -0.80; 95% CI - 1.34, -0.27; P = 0.003) and less incidence of postmastectomy pain syndrome (relative risk 0.79; 95% CI 0.63, 0.99; P = 0.043). CONCLUSION: Ketamine is an effective and safe multimodal analgesic in patients undergoing breast surgery, administered both intravenously and when added to bupivacaine in paravertebral blocks. In addition, ketamine showed a long-term benefit for preventing postoperative depression and postmastectomy pain syndrome.

Effect of perioperative intravenous lidocaine for patients undergoing spine surgery: A meta-analysis and systematic review.

BACKGROUND: Perioperative intravenous lidocaine has been reported to have analgesic and opioid-sparing effects in many kinds of surgery. Several studies have evaluated its use in the settings of spine surgery. The aim of the study is to examine the effect of intravenous lidocaine in patients undergoing spine surgery. METHODS: We performed a quantitative systematic review. Databases of PubMed, Medline, Embase database and Cochrane library were investigated for eligible literatures from their establishments to June, 2019. Articles of randomized controlled trials that compared intravenous lidocaine to a control group in patients undergoing spine surgery were included. The primary outcome was postoperative pain intensity. Secondary outcomes included postoperative opioid consumption and the length of hospital stay. RESULT: Four randomized controlled trials with 275 patients were included in the study. postoperative pain compared with control was reduced at 6 hours after surgery (WMD -0.50, 95%CI, -0.76 to -0.25, P < .001), at 24 hours after surgery (WMD -0.50, 95%CI, -0.70 to -0.29, P < .001) and at 48 hours after surgery (WMD -0.57, 95%CI, -0.96 to -0.17, P = .005). The effect of intravenous lidocaine on postoperative opioid consumption compared with control revealed a significant effect (WMD -15.36, 95%CI, -21.40 to -9.33 mg intravenous morphine equivalents, P < .001). CONCLUSION: This quantitative analysis of randomized controlled trials demonstrated that the perioperative intravenous lidocaine was effective for reducing postoperative opioid consumption and pain in patients undergoing spine surgery. The intravenous lidocaine should be considered as an effective adjunct to improve analgesic outcomes in patients undergoing spine surgery. However, the quantity of the studies was very low, more research is needed.

Comparative efficacy of glimepiride and metformin in monotherapy of type 2 diabetes mellitus: meta-analysis of randomized controlled trials.

BACKGROUND: Metformin treatment has been the most recommended monotherapy of type 2 diabetes mellitus (T2DM) for decades but is challenged by new antidiabetic drugs. This study conducted a meta-analysis of randomized controlled trials (RCT) comparing the efficacy of metformin and glimepiride in monotherapy of T2DM. METHODS: A literature search for RCTs on glimepiride and metformin was conducted on the bibliographic databases, including PubMed, Cochrane Library and ScienceDirect, from their inceptions to 25 Mar 2013. All RCTs were selected according to pre-specified eligibility criteria. The quality of articles was assessed with the Cochrane's risk of bias tool. Statistical meta-analysis evaluated the overall effects and biochemical indices of T2DM. Sensitivity and subgroup analyses evaluated the robustness and explained the heterogeneity of the results. Begg and Egger's tests quantified possible publication biases. Results were represented as "standard mean difference or odds ratio [95% confidence internals] P value". RESULTS: Fifteen RCTs with 1681 adult T2DM patients were included for meta-analysis. Metformin was not better than glimepiride in overall efficacy in controlling the levels of HbA1c, postprandial blood sugar (PPBS), fasting plasma insulin (FINS), systolic and diastolic blood pressures (SBP and DBP), and high density lipoprotein (HDL). Metformin was only more effective than glimepiride in controlling the levels of total cholesterol (TC, 0.33 [0.03, 0.63], P = 0.03), low-density lipoprotein (LDL, 0.35 [0.16, 0.53], P = 0.0002) and triglycerides (TG, 0.26 [0.05, 0.46], P = 0.01). Odds ratios of adverse events showed that glimepiride was more likely to induce hypoglycemia episodes and metformin was with a higher risk of gastrointestinal upset. CONCLUSION: Metformin was not significantly better than glimepiride in glycemic control of T2DM, suggesting that glimepiride would be a good choice second to metformin in the monotherapy of T2DM.