The effects of tranexamic acid on platelets in patients undergoing cardiac surgery: a systematic review and meta-analysis.

This meta-analysis was designed to evaluate the effects of tranexamic acid (TXA) on platelets in patients undergoing cardiac surgery (CS). Relevant trials were identified by computerized searches of PUBMED, Cochrane Library, EMBASE, OVID, China National Knowledge Infrastructure (CNKI), Wanfang Data and VIP Data till Jun 4th, 2022, were searched using search terms "platelet", "Tranexamic acid", "cardiac surgery", "randomized controlled trial" database search was updated on Jan 1st 2023. Primary outcomes included platelet counts, function and platelet membrane proteins. Secondary outcome included postoperative bleeding. Search yielded 49 eligible trials, which were finally included in the current study. As compared to Control, TXA did not influence post-operative platelet counts in adult patients undergoing on- or off-pump CS, but significantly increased post-operative platelet counts in pediatric patients undergoing on-pump CS [(WMD = 16.72; 95% CI 6.33 to 27.10; P = 0.002)], significantly increased post-operative platelet counts in adults valvular surgery [(WMD = 14.24; 95% CI 1.36 to 27.12; P = 0.03). Additionally, TXA improved ADP-stimulated platelet aggression [(WMD = 1.88; 95% CI 0.93 to 2.83; P = 0.0001)] and improved CD63 expression on platelets [(WMD = 0.72; 95% CI 0.29 to 1.15; P = 0.001)]. The current study demonstrated that TXA administration did not affect post-operative platelet counts in adult patients undergoing either on- or off-pump CABG, but significantly increased post-operative platelet counts in pediatric patients undergoing on-pump CS and adults valvular surgery. Furthermore, TXA improved ADP-stimulated platelet aggression and improved CD63 expression on platelets. To further confirm this, more well designed and adequately powered randomized trials are needed.

The efficacy and safety of intravenous administration of tranexamic acid in patients undergoing cardiac surgery: Evidence from a single cardiovascular center.

BACKGROUND: The current study was performed to systemically review the efficacy and safety of tranexamic acid (TXA) in patients undergoing cardiac surgery at a single large-volume cardiovascular center. METHODS: A computerized search of electronic databases was performed to identify all relevant studies using search terms till December 31st, 2021. The primary outcomes were postoperative blood loss and the composite incidence of mortality and morbidities during hospitalization. Secondary outcomes included postoperative massive bleeding and transfusion, postoperative recovery profiles, coagulation functions, inflammatory variables, and biomarkers of vital organ injury. RESULTS: Database search yielded 23 qualified studies including 27,729 patients in total. Among them, 14,136 were allocated into TXA group and 13,593 into Control group. The current study indicated that intravenous TXA significantly reduced total volume of postoperative bleeding in both adult and pediatric patients, and that medium- and high-dose TXA were more effective than low-dose TXA in adult patients (P < .05). The current study also demonstrated that intravenous TXA, as compared to Control, remarkably reduced postoperative transfusion incidences and volume of red blood cell and fresh frozen plasma, and reduced postoperative transfusion incidence of platelet concentrates (PC) (P < .05) without obvious dose-effects (P > .05), but TXA did not reduce PC transfusion volume postoperatively in adult patients (P > .05). For pediatrics, TXA did not significantly reduce postoperative transfusion incidence and volume of allogenic red blood cell, fresh frozen plasma and PC (P > .05). Additionally, the current study demonstrated that intravenous TXA did not influence the composite incidence of postoperative mortality and morbidities in either adults or pediatrics during hospitalization (P > .05), and that there was no obvious dose-effect of TXA in adult patients (P > .05). CONCLUSIONS: This current study suggested that intravenous TXA significantly reduced total volume of postoperative bleeding in both adult and pediatric patients undergoing cardiac surgery at the single cardiovascular center without increasing the composite incidence of mortality and morbidities.

Corrigendum: Anesthesia management of patients undergoing off-pump coronary artery bypass grafting: A retrospective study of single center.

[This corrects the article DOI: 10.3389/fsurg.2022.1067750.].

Levosimendan administration is not associated with increased risk of bleeding and blood transfusion requirement in patients undergoing off-pump coronary artery bypass grafting: a retrospective study from single center.

BACKGROUND: Levosimendan (LEVO) is a positive inotropic drug which could increase myocardial contractility and reduce the mortality rate in cardiac surgical patients. However, Whether LEVO is associated with postoperative bleeding and blood transfusion in cardiac surgical patients is controversial. Therefore, the current study was designed to investigate the impact of LEVO administration on bleeding and blood transfusion requirement in off-pump coronary artery bypass grafting (OPCAB) patients. METHODS: In a retrospective analysis, a total of 292 patients, aged 40-87 years, undergoing elective OPCAB between January 2019 and July 2019, were divided into LEVO group (n = 151) and Control group (n = 141). Patients in LEVO group continuously received LEVO at a rate of 0.1-0.2 µg kg-1 min-1 after anesthesia induction until 24 hours after OPCAB or patients in Control group received no LEVO. The primary outcome was postoperative chest drainage volume. The secondary outcomes were reoperation for postoperative bleeding, transfusion requirement of red blood cells (RBCs), fresh frozen plasma (FFP) and platelet concentrate (PC), etc. Comparisons of two groups were performed with the Student's t-test or Wilcoxon-Mann-Whitney test. RESULTS: There was no significant difference with respect to chest drainage volume ((956.29 ± 555.45) ml vs (1003.19 ± 572.25) ml, p = 0.478) and the incidence of reoperation for postoperative bleeding (1.32% vs 1.42%, p = 0.945) between LEVO group and Control group. The transfusion incidence and volume of allogeneic RBCs, FFP, and PC were comparable between two groups. CONCLUSIONS: LEVO administration was neither associated with more postoperative blood loss nor increased allogeneic blood transfusion requirement in OPCAB patients.

Anesthetic management of patients undergoing mediastinal mass operation.

Objectives: To summarize the anesthetic management of patients undergoing mediastinal mass operation. Methods: Electronic databases were searched to identify all case reports of patients undergoing mediastinal mass operation. Information such as clinical characteristics, perioperative management and patients' outcomes were abstracted and analyzed. Results: Seventy-seven case reports with 85 patients aging from 34 days to 81 years were included. Mediastinal masses were located in anterior (n = 48), superior (n = 15), middle (n = 9) and posterior (n = 9) mediastinum, respectively. Clinical manifestations included dyspnea (n = 45), cough (n = 29), chest or radiating pain (n = 12), swelling (n = 8), fever (n = 7) and chest distress (n = 4). Most patients (n = 75) had signs of compression or invasion of vital structures. General anesthesia (n = 76) was the most commonly used method of anesthesia. Muscle relaxants were administered in 35 patients during anesthesia induction and spontaneous respiration was maintained in 37 patients. Mediastinal mass syndrome (MMS) occurred in 39 cases. Extracorporeal circulation was utilized in 20 patients intraoperatively. Three patients experienced cardiac arrest after ventilation failure and two patients died intraoperatively and one postoperatively. Conclusions: Peri-operative management of patients undergoing mediastinal mass operation could be challenging. Pre-operative multi-disciplinary discussion, well-planned anesthetic management and pre-determined protocols for emergency situations are all vital to patient safety.

Furosemide does not reduce the incidence of postoperative acute kidney injury in adult patients undergoing cardiac surgery: A PRISMA-compliant systematic review and meta-analysis.

OBJECTIVE: Acute kidney injury (AKI) is a common complication of cardiac surgical patients, the occurrence of which is multifactorial. Furosemide is the most common loop diuretic and widely used in cardiac surgery to reduce fluid overload, increase tubular flow and urine output. It remains unknown whether furosemide affects the incidence or prognosis of cardiac surgery-induced acute kidney injury (CS-AKI). Therefore, the current study was performed to address this question. METHODS: PubMed, Embase, Scopus, Cochrane Library, and Web of Science databases were searched for relevant studies. Primary outcomes of interest included postoperative CS-AKI incidence, need for renal replacement therapy (RRT) rate. Secondary outcomes of interest included postoperative serum creatinine (Scr) and blood urea nitrogen (BUN) levels, postoperative mechanical ventilation duration (MVD), length of stay (LOS) in intensive care unit (ICU) and in hospital, and mortality. The odds ratio (OR) and/or the weighted mean difference (WMD) with 95% confidence interval (CI) were used to pool the data. RESULTS: Database search yielded six studies including 566 adult patients, and 283 patients were allocated into Group Furosemide and 283 into Group Control (Placebo). Heterogeneity between studies was deemed acceptable, and the publication bias was low. Meta-analysis suggested that furosemide administration in adult cardiac surgical patients had no effect on CS-AKI incidence (n = 4 trials; OR = 0.92; 95% CI: 0.37-2.30; p = .86; I2 = 57%) and need for RRT rate (n = 2 trials; OR = 4.13; 95% CI: 0.44-38.51; p = .21; I2 = 0%). Diversely, furosemide administration in adult cardiac surgical patients significantly decreased postoperative BUN level (n = 3 trials; WMD = 0.71; 95% CI: 0.10-1.33; p = .02; I2 = 0%), postoperative MVD (n = 2 trials; WMD = -3.13; 95% CI: -3.78 to -2.49; p < .00001; I2 = 0%) and postoperative LOS in ICU (n = 3 trials; WMD = -0.47; 95% CI: -0.76 to -0.18; p = .001; I2 = 0%). However, it had no significant impact on postoperative Scr level, postoperative LOS in hospital, and postoperative mortality. CONCLUSION: This meta-analysis suggested that furosemide administration in adult cardiac surgical patients had no significant effect on CS-AKI incidence, need for RRT rate, postoperative Scr level, LOS in hospital and mortality, but could reduce postoperative BUN level, MVD, and LOS in ICU. As only a limited number of studies were included, these results should be interpreted carefully and cautiously. Future high-quality randomized controlled trials are needed to define the role of furosemide in CS-AKI prevention and management.

Anti-inflammatory effect of tranexamic acid on adult cardiac surgical patients: A PRISMA-compliant systematic review and meta-analysis.

Objective: This study aims to evaluate the anti-inflammatory effect of tranexamic acid (TXA) on adult cardiac surgical patients. Methods: PubMed, Embase, Ovid, Web of Science, CNKI, VIP, and WANFANG databases were systematically searched using the related keywords for cardiac surgical randomized controlled trials (RCTs) published from their inception to February 1, 2022. The primary outcomes were postoperative inflammatory biomarkers levels. The secondary outcomes were postoperative systemic inflammatory response syndrome and other major postoperative outcomes. The odds ratios and/or the weighted mean difference (WMD) with a 95% confidence interval (CI) were used to pool the data. Results: Ten RCTs with 770 adult cardiac surgical patients were included. Compared with placebo, TXA achieved statistically significant inhibition of the postoperative interleukin (IL)-6 level (postoperative 6 h: n = 6 trials; WMD -31.66; 95% CI: -45.90, -17.42; p < 0.0001; I 2 = 93%; postoperative 24 h: n = 8 trials; WMD, -44.06; 95% CI: -69.21, -18.91; p = 0.006; I 2 = 100%); IL-8 level postoperative 24 h, TNF-α level postoperative 24 h, NE level postoperative 6 h: n = 3 trials; WMD, -36.83; 95% CI: -68.84, -4.83; p = 0.02; I 2 = 95%); tissue necrosis factor alpha (TNF-α) level (postoperative 6 h: n = 3 trials; WMD, -7.21; 95% CI: -12.41, -2.01; p = 0.007; I 2 = 47%; postoperative 24 h: n = 5 trials; WMD, -10.02; 95% CI: -14.93, -5.12; p < 0.0001; I 2 = 94%); and neutrophil elastase (NE) level (postoperative 6 h: n = 3 trials; WMD, -66.93; 95% CI: -111.94, -21.92; p = 0.004; I 2 = 86%). However, TXA achieved no statistically significant influence on the postoperative 24 h NE level. Conclusions: TXA had a significant anti-inflammatory effect in adult cardiac surgical patients, as evidenced by the reduction of multiple postoperative proinflammatory biomarkers levels, but these results should be interpreted carefully and cautiously, as only a limited number of studies were included and there was high heterogeneity between them. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/#recordDetails, identifier: CRD42022312919.

Efficacy of dezocine on preventing opioid-induced cough during general anaesthesia induction: a PRISMA-compliant systematic review and meta-analysis.

OBJECTIVES: To systematically review the effects of dezocine (DZC) on the occurrence rate and severity of opioid-induced cough (OIC). DESIGN: Systematic review and meta-analysis DATA SOURCES: PubMed, Embase, Cochrane Library, Ovid, Web of Science as well as Chinese BioMedical Literature & Retrieval System, China National Knowledge Infrastructure, Wanfang and VIP Data were searched from 1978 to 31 December 2020. INCLUSION CRITERIA: All randomised controlled trials (RCTs) comparing DZC with placebo on the occurrence rate and severity of OIC. DATA ANALYSIS: All data were analysed by using RevMan V.5.3. Each outcome was tested for heterogeneity, and randomised-effects or fixed-effects model was used in the presence or absence of significant heterogeneity. RESULTS: Our search yielded 33 RCTs including 4442 patients, and 2521 patients were allocated into the DZC group and 1921 into the control group. Fentanyl was administrated in 1880 patients and sufentanil in 2562 patients during the induction of general anaesthesia. The meta-analysis demonstrated that DZC significantly reduced the occurrence rate of OIC induced by either fentanyl (8.8% vs 49.7%, OR=0.07, 95% CI 0.04 to 0.12, p<0.00001) or sufentanil (5.0% vs 41.5%, OR=0.07, 95% CI 0.04 to 0.12, p<0.00001). The meta-analysis also indicated that the occurrence rate of mild, moderate and severe OIC in the DZC group was remarkably lower than that of the control group (mild: 3.6% vs 13.6%, OR=0.19, 95% CI 0.14 to 0.25, p<0.00001; moderate: 2.0% vs 13.6%, OR=0.12, 95% CI 0.09 to 0.18, p<0.00001; severe: 1.0% vs 13.9%, OR=0.08, 95% CI 0.05 to 0.12, p<0.00001). Additionally, the current meta-analysis indicated that DZC pretreatment was not associated with increased occurrence rate of adverse effects (7.0% vs 4.2%, OR=2.34, 95% CI 0.60 to 9.14, p=0.22) except for dizziness (11.8% vs 0%, OR=8.06, 95% CI 1.40 to 46.35, p=0.02). CONCLUSION: This meta-analysis demonstrated that DZC significantly inhibited OIC and may be used to manage OIC. More high-quality RCTs are needed to complement the safety of DZC. PROSPERO REGISTRATION NUMBER: CRD42019141255.

Tranexamic acid reduces postoperative blood loss in Chinese pediatric patients undergoing cardiac surgery: A PRISMA-compliant systematic review and meta-analysis.

BACKGROUND: Tranexamic acid has been increasingly used for blood conservation in cardiac surgery. However, the evidence supporting the routine use of tranexamic acid in Chinese pediatric patients undergoing cardiac surgery remains weak. This meta-analysis aimed to systematically review the efficacy of tranexamic acid when applying to Chinese pediatric patients undergoing cardiac surgery. PARTICIPANTS: Chinese pediatric patients undergoing cardiac surgery. INTERVENTIONS: Tranexamic acid or control drugs (saline/blank). METHODS: PUBMED, Cochrane Library, EMBASE, China National Knowledge Infrastructure (CNKI), Wanfang Data, and VIP Data till May 4, 2021, database search was updated on August 1. Primary outcomes of interest included postoperative bleeding, allogeneic transfusion, and reoperation for bleeding. Secondary outcomes of interest included postoperative recovery. For continuous/dichotomous variables, treatment effects were calculated as weighted mean difference (WMD)/odds ratio and 95% confidence interval. RESULTS: A database search yielded 15 randomized controlled trials including 1641 patients, where 8 studies were allocated into non-cyanotic congenital group, 5 were allocated into cyanotic congenital group, and the other 2 were allocated into combined cyanotic/non-cyanotic group. This meta-analysis demonstrate that tranexamic acid administration can reduce the postoperative 24 hours blood loss in non-cyanotic, cyanotic, and combined cyanotic/non-cyanotic patients, the red blood cell transfusion in non-cyanotic and cyanotic patients, and the fresh frozen plasma transfusion in non-cyanotic and combined cyanotic/non-cyanotic patients. CONCLUSION: This meta-analysis demonstrates that tranexamic acid is highly effective in reducing the blood loss in Chinese pediatric cardiac surgery, but it behaves poorly when it comes to the transfusion requirement. To further confirm this, more well-designed and adequately-powered randomized trials are needed.

Patient Blood Management: Single Center Evidence and Practice at Fuwai Hospital.

Blood loss and blood transfusion requirement are important quality control indicators of cardiovascular surgery and cardiovascular anesthesia. Patient blood management (PBM) is an evidence-based, multidisciplinary approach to optimizing the care of patients who may need transfusion, which encompasses anemia management, hemodilution, cell salvage, hemostatic treatment, and other approaches to reducing bleeding and minimizing blood transfusion. PBM in cardiovascular surgery is a "team sport" that involves cardiac and vascular surgeons, anesthesiologists, perfusionist, intensivists, and other health care providers. The current work provides an overview of evidence and practice of PBM at Fuwai Hospital. Implementation of PBM should also take local resource availability and cost-effectiveness of different devices, drugs, technologies, and techniques into consideration.

Anesthesia management of patients undergoing off-pump coronary artery bypass grafting: A retrospective study of single center.

Background: To summarize the current practice of anesthesia management for Chinese patients undergoing off-pump coronary artery bypass (OPCAB) surgery at a large-volume cardiovascular center. Materials and methods: The clinical data of consecutive patients undergoing isolated, primary OPCAB surgery during the period from September 2019 to December 2019 were retrospectively analyzed. Patient characteristics, intraoperative data, and short-term outcomes were extracted from the Hospital Information System and the Anesthesia Information Management System. Results: A total of 255 patients who underwent OPCAB surgery were enrolled in the current study. High-dose opioids and short-acting sedatives were the most commonly administrated anesthetics intraoperatively. Pulmonary arterial catheter insertion is frequently performed in patients with serious coronary heart disease. Goal-directed fluid therapy, a restricted transfusion strategy, and perioperative blood management were routinely used. Rational usages of inotropic and vasoactive agents facilitate hemodynamic stability during the coronary anastomosis procedure. Four patients underwent re-exploration for bleeding, but no death was observed. Conclusions: The study introduced the current practice of anesthesia management at the large-volume cardiovascular center, and the short-term outcomes indicated the efficacy and safety of the practice in OPCAB surgery.

The efficacy and safety of pre-emptive methoxamine infusion in preventing hypotension by in elderly patients receiving spinal anesthesia: A PRISMA-compliant protocol for systematic review and meta-analysis.

BACKGROUND: Hypotension is frequent after spinal anesthesia, especially in elderly patients. Whether pre-emptive methoxamine infusion is effective and safe to prevent spinal anesthesia-induced hypotension is still a controversial issue, to dress this knowledge lack, we performed a systemic review and meta-analysis to evaluated it. PARTICIPANTS: Elderly patients undergoing spinal anesthesia. INTERVENTIONS: Administration of methoxamine prior to spinal anesthesia. METHODS: We searched PUBMED, Cochrane Library, EMBASE, China National Knowledge Infrastructure, Wanfang Database, and VIP Database, Chinese BioMedical Literature & Retrieval System from January 1st 1978 to February 28th 2022. Primary outcomes of interests included hemodynamic parameters, such as systolic blood pressure, diastolic blood pressure, mean arterial pressure, heart rate. Secondary outcomes of interests included the incidence of intraoperative hypotension, bradycardia, nausea and vomiting, vasopressors requirement, intraoperative blood loss. For continuous or dichotomous variables, treatment effects were calculated as weighted mean difference or odds ratio, respectively. RESULTS: Our search yielded 8 randomized controlled trials including 480 patients, and 240 patients were allocated into methoxamine group and 240 into control group. Meta-analysis demonstrated that pre-emptive methoxamine infusion in preventing hypotension by in elderly patients receiving spinal anesthesia had higher blood pressures, lower heart rates. Compared with the control group, the incidence of perioperative hypotension in elderly patients was lower, and elderly patients had less requirement for vasopressor in methoxamine group. CONCLUSION: This meta-analysis demonstrated that pre-emptive methoxamine infusion in elderly patients receiving spinal anesthesia can improve blood pressure, slow down heart rate, reduce the incidence of hypotension and requirement for vasopressor. However, these findings should be interpreted rigorously. Further well-conducted trials are required to confirm this.

Anesthesia Management at Fuwai Hospital:Practice, Evidence and Outcomes.

Fuwai Hospital was established in 1956 and the Anesthesia Department of Fuwai Hospital was one of the earliest anesthesia departments then in China. Under the leadership of several department directors and with the concerted efforts of all generations of colleagues, the Anesthesia Department of Fuwai Hospital has dramatically transformed, upgraded and modernized. For more than six decades, the Anesthesia Department has been providing high-quality peri-operative anesthesia care for cardiovascular surgeries, conducting innovative experimental and clinical researches, and offering comprehensive training on cardiovascular anesthesiology for professionals across China. Currently, Fuwai Hospital is the National Center for Cardiovascular Diseases of China and one of the largest cardiovascular centers in the world. The present review introduces the Anesthesia Department of Fuwai Hospital, summarizes its current practice of anesthesia management, the outcomes of cardiovascular surgeries at Fuwai Hospital, accumulates relevant evidence, and provides prospects for future development of cardiovascular anesthesiology.

Anesthetic Induction With Etomidate in Cardiac Surgical Patients: A PRISMA-Compliant Systematic Review and Meta-Analysis.

OBJECTIVE: This meta-analysis aimed to systematically review the effects of etomidate (ETM) during anesthetic induction on patients undergoing cardiac surgery. DESIGN: Systematic review and meta-analysis. SETTING: Operating room. PARTICIPANTS: Patients undergoing cardiac surgery. INTERVENTIONS: ETM or control drugs. MEASUREMENTS AND MAIN RESULTS: PubMed, Cochrane Library, OVID, and EMBASE were searched through August 31, 2020. Primary outcomes included hemodynamic profiles and stress responses. Secondary outcomes included morbidity, mortality, and postoperative recovery. For continuous/dichotomous variables, treatment effects were calculated as weighted mean difference (WMD)/odds ratio (OR) and 95% confidence interval (CI). A database search yielded 18 randomized controlled trials including 1,241 patients. The present meta-analysis demonstrated that ETM-anesthetized patients had lower heart rates (WMD, -3.31; 95% CI -5.43 to -1.19; p = 0.002), higher blood pressures (systolic blood pressure: WMD, 12.02; 95% CI 6.24 to 17.80; p < 0.0001; diastolic blood pressure: WMD, 5.23; 95% CI 2.39 to 8.08; p = 0.0003; mean arterial pressure (MAP): WMD, 8.64; 95% CI 5.85 to 11.43; p < 0.00001), less requirement for vasopressor (OR, 0.26; 95% CI 0.15 to 0.44; p < 0.00001), and more nitroglycerin usage (OR, 14.89; 95% CI 4.92 to 45.08; p < 0.00001) during anesthetic induction. Current meta-analysis also demonstrated that single-dose ETM lowered cortisol levels transiently and did not have a significant effect on endogenous norepinephrine and epinephrine levels and was not associated with increased postoperative inotrope and/or vasopressor requirement. Additionally, the meta-analysis suggested that ETM anesthesia was associated with neither increased mortality nor morbidity, except a higher incidence of transient adrenal insufficiency in ETM recipients. CONCLUSION: The present meta-analysis suggested that single-dose ETM during anesthetic induction could be associated with more stable hemodynamics, transient and reversible lower cortisol levels, and a higher adrenal insufficiency incidence, but not worse outcomes in cardiac surgical patients.

The effect of levosimendan on postoperative bleeding and blood transfusion in cardiac surgical patients: a PRISMA-compliant systematic review and meta-analysis.

BACKGROUND: Levosimendan (LEVO), is an inotropic agent which has been shown to be associated with better myocardial performance, and higher survival rate in cardiac surgical patients. However, preliminary clinical evidence suggested that LEVO increased the risk of post-operative bleeding in patients undergoing valve surgery. Currently, there has been no randomized controlled trials (RCTs) designed specifically on this issue. Therefore, we performed present systemic review and meta-analysis. METHODS: Electronic databases were searched to identify all RCTs comparing LEVO with Control (placebo, blank, dobutamine, milrinone, etc). Primary outcomes include post-operative blood loss and re-operation for bleeding. Secondary outcomes included post-operative transfusion of red blood cells (RBC), fresh frozen plasma (FFP) and platelet concentrates (PC). For continuous variables, treatment effects were calculated as weighted mean difference (WMD) and 95% confidential interval (CI). For dichotomous data, treatment effects were calculated as odds ratio (OR) and 95% CI. RESULTS: Search yielded 15 studies including 1,528 patients. Meta-analysis suggested that, LEVO administration was not associated with increased risk of reoperation for bleeding post-operatively (OR = 1.01; 95%CI: 0.57 to 1.79; p = 0.97) and more blood loss volume (WMD = 28.25; 95%CI: -19.21 to 75.72; p = 0.24). Meta-analysis also demonstrated that, LEVO administration did not increase post-operative transfusion requirement for RBC (rate: OR = 0.97; 95%CI: 0.72 to 1.30; p = 0.83 and volume: WMD = 0.34; 95%CI: -0.55 to 1.22; p = 0.46), FFP (volume: WMD = 0.00; 95%CI: -0.10 to 0.10; p = 1.00) and PC (rate: OR = 1.01; 95%CI: 0.41 to 2.50; p = 0.98 and volume: WMD = 0.00; 95%CI: -0.05 to 0.04; p = 0.95). CONCLUSION: This meta-analysis suggested that, peri-operative administration of LEVO was not associated with increased risks of post-operative bleeding and blood transfusion requirement in cardiac surgical patients.

The effect of tranexamic acid on the values of activated clotting time in patients undergoing cardiac surgery: A PRISMA-compliant systematic review and meta-analysis.

STUDY OBJECTIVE: Activated clotting time (ACT) is a non-specific test to evaluate the adequacy of systemic heparinization whose value could be influenced by many factors. Tranexamic acid (TXA) is a widely used antifibrinolytic agent worldwide and whether TXA influences ACT value in cardiac surgical patients remains unknown. Current study was performed to address this question. DESIGN: Systematic review and meta-analysis. PUBMED, Cochrane Library, EMBASE, OVID and Chinese BioMedical Literature & Retrieval System were searched using search terms "tranexamic acid", "activated clotting time", "cardiac surgery", "randomized controlled trial" till May 7th, 2020, to identify all relevant randomized controlled trials (RCTs). SETTING: Operating room. PATIENTS: Cardiac surgical patients. INTERVENTIONS: TXA or placebo. MEASUREMENTS: Primary outcomes of interest included peri-operative ACT values. Secondary outcomes of interest include heparin dosage, protamine dosage, postoperative bleeding and blood transfusion. MAIN RESULTS: Search yielded 13 studies including 1168 patients, and 619 patients were allocated into Group TXA and 549 into Group Control (placebo). Meta-analysis suggested that, ACT values after heparinization [(WMD = -1.45; 95%CI: -12.52 to 15.43; P = 0.84)] and after protamine [(WMD = -1.18; 95%CI: -2.81 to 0.46; P = 0.16)] were comparable between Group TXA and Group Control, and that TXA did not influence heparin dose in adult patients [(WMD = 0.38; 95%CI: 0.30 to 0.46; P<0.00001) with no heterogeneity (I2 = 4%, P = 0.35)] and protamine dose for heparin reversal [(WMD = 5.23; 95%CI: -0.33 to 10.80; P = 0.07) with no heterogeneity (I2 = 0, P = 0.58)]. Meta-analysis also demonstrated that, TXA administration significantly reduced post-operative bleeding volume [(WMD = -126.33; 95%CI: -177.46 to -75.19; P < 0.0001), post-operative red blood cell (RBC) transfusion volume [(WMD = -71.86; 95% CI: -88.22 to -55.50; P < 0.00001), fresh frozen plasma (FFP) transfusion volume [(WMD = -13.83; 95% CI: -23.67 to -4.00; P = 0.006) and platelet concentrate (PC) transfusion volume [(WMD = -0.20; 95% CI: -0.29 to -0.10; P < 0.0001). CONCLUSION: This meta-analysis suggested that, TXA administration did not influence ACT value, heparin and protamine doses, but significantly reduced post-operative blood loss and transfusion requirement in cardiac surgical patients.

Is dezocine effective and safe in preventing opioids-induced cough during general anaesthesia induction? A protocol for systematic review and meta-analysis.

INTRODUCTION: Cough is often observed when administrating a bolus of opioids. Opioid-induced cough (OIC) is mostly transient, benign and self-limiting, but could be associated with adverse effects. Numerous pharmacological and non-pharmacological interventions have been used to manage OIC with controversial efficacy and safety. Recent studies suggested that, pretreatment of intravenous dezocine (DZC) could completely suppress OIC during anaesthesia induction. To address this knowledge lack, we will perform a systemic review and meta-analysis to evaluate the efficacy of DZC on OIC and possible complications. We provide here a protocol that will outline the methods and analyses planned for the systematic review. METHODS: PubMed, Embase, Cochrane Library, Web of Science as well as Chinese BioMedical Literature & Retrieval System (SinoMed), China National Knowledge Infrastructure, Wanfang Data and VIP Data will be searched from 1978 to 31 December 2019 to identify all randomised controlled trials comparing DZC with placebo on the incidence and severity of OIC. Primary outcomes of interest include the incidence and severity of OIC. Secondary outcomes of interest include possible complications or adverse effects of DZC. Two authors will independently extract relevant variables and outcome data. For continuous variables, treatment effects will be calculated as weighted mean difference and 95% CI. For dichotomous data, treatment effects will be calculated as OR and 95% CI. Each outcome will be tested for heterogeneity, and randomised-effects or fixed-effects model will be used in the presence or absence of significant heterogeneity. Sensitivity analyses will be done by examining the influence of statistical model and individual trial(s) on estimated treatment effects. Publication bias will be explored through visual inspection of funnel plots of the outcomes. Statistical significance will be defined as p<0.05. ETHICS AND DISSEMINATION: This study is a protocol of meta-analysis of previously published literatures, ethical approval was not necessary according to the Ethical Committee of Fuwai Hospital. The study will be submitted to a peer-reviewed journal and disseminated via research presentations. PROSPERO REGISTRATION NUMBER: CRD42019141255.