Risk-adjusted perioperative bridging anticoagulation reduces bleeding complications without increasing thromboembolic events in general and visceral surgery.

BACKGROUND: Perioperative bridging of oral anticoagulation increases the risk of bleeding complications after elective general and visceral surgery. The aim of this study was to explore, whether an individual risk-adjusted bridging regimen can reduce bleeding events, while still protecting against thromboembolic events. METHODS: We performed a quality improvement study comparing bridging parameters and postoperative outcomes before (period 1) and after implementation (period 2) of a new risk-adjusted bridging regimen. The primary endpoint of the study was overall incidence of postoperative bleeding complications during 30 days postoperatively. Secondary endpoints were major postoperative bleeding, minor bleeding, thromboembolic events, postoperative red blood cell transfusion, perioperative length-of-stay (LOS) and in-hospital mortality. RESULTS: A total of 263 patients during period 1 and 271 patients during period 2 were compared. The included elective operations covered the entire field of general and visceral surgery. The overall incidence of bleeding complications declined from 22.1% during period 1 to 10.3% in period 2 (p < 0.001). This reduction affected both major as well as minor bleeding events (8.4% vs. 4.1%; p = 0.039; 13.7% vs. 6.3%; p = 0.004). The incidence of thromboembolic events remained low (0.8% vs. 1.1%). No changes in mortality or length-of-stay were observed. CONCLUSION: It is important to balance the individual thromboembolic and bleeding risks in perioperative bridging management. The risk adjusted bridging regimen reduces bleeding events in general and visceral surgery while the risk of thromboembolism remains comparably low.

Postoperative nausea and vomiting: risk factors, prediction tools, and algorithms.

PURPOSE OF REVIEW: Postoperative/postdischarge nausea and vomiting (PONV/PDNV) remain relevant issues in perioperative care. Especially in ambulatory surgery, PONV can prevent discharge or lead to unplanned readmission. RECENT FINDINGS: The evidence for the management of PONV is now quite good but is still inadequately implemented. A universal, multimodal rather than risk-adapted approach for PONV prophylaxis is now recommended. The evidence on PDNV is insufficient. SUMMARY: PDNV management is based primarily on consequent prophylaxis and therapy of PONV.

Postoperative/postdischarge nausea and vomiting: evidence-based prevention and treatment.

PURPOSE OF REVIEW: Postoperative/postdischarge nausea and vomiting (PONV/PDNV) remains a relevant issue in perioperative care. Especially in outpatient surgery, PONV can prevent discharge or lead to unplanned readmission. RECENT FINDINGS: Evidence on prophylaxis and treatment of PONV is growing, but implementation remains poor. SUMMARY: A liberal, universal PONV management is now endorsed by the guidelines. Specific evidence concerning prevention and (at-home) treatment of PDNV is still scarce.

[Postpartum hemorrhage : Interdisciplinary consideration in the context of patient blood management]. / Postpartale Hämorrhagie : Interdisziplinäre Betrachtung im Kontext des Patient Blood Management.

Postpartum hemorrhage (PPH) nowadays still represents a severe complication of both a vaginal delivery and a cesarean section. In German-speaking areas a new definition of the term has recently become established and the nomenclature with respect to the severe form of PPH was dropped. The handling of misoprostol as a uterotonic during treatment of PPH is also new, which is available in Germany only as a medical direct import. For adequate diagnostics and targeted treatment interdisciplinary and standardized algorithms should be established and the specialist disciplines involved should be sensitized to this problem. In addition to an adequate hemostasis, a developing coagulopathy must be recognized at an early stage and treated with targeted coagulation management. Through implementation concepts, particularly the second pillar (minimization of blood loss) and the third pillar (rational use of blood transfusions) of patient blood management, various aspects for improvement of treatment of a PPH can be identified.

[Patient blood management in the preparation for birth, obstetrics and postpartum period]. / Patient Blood Management in der Geburtsvorbereitung, Geburtshilfe und postpartalen Phase.

The implementation of patient blood management (PBM) is increasingly becoming standard in operative medicine. Recently, interest has also been shown for the vulnerable collective of pregnant women and neonates. As the information regarding anesthesiological procedures for pregnant women and the peripartum period including an informed consent process should be carried out long before childbirth, this provides a good possibility in this connection to incorporate PBM. An anesthesiological risk estimation as well as the diagnostic workup and treatment of potential anemia should be carried out during the pregnancy. Furthermore, loss of blood in anticipation of bleeding complications should be reduced by interdisciplinary preventive measures and an individually coordinated postpartum care should be organized. This results in an early diagnosis of anemia or iron deficiency with subsequent treatment also postpartum, analogous to the prepartum period.

[Peri- and Postoperative Anaemia Management]. / Outcome-relevante Anästhesiologie: peri- und postoperative Anämiebehandlung.

Patient Blood Management (PBM) aims to diagnose and treat preoperative anaemia, avoid unnecessary blood loss, and enable rational use of blood products. Due to various limitations, treatment of preoperative anaemia has been successful in only a few German hospitals to date. Thus, the peri- and postoperative phase is increasingly becoming important for implementing various preventive and therapeutic measures for the treatment of (postoperative) anaemia. These will be comprehensively presented in the following.

Vitamin D deficiency in critically ill COVID-19 ARDS patients.

BACKGROUND & AIMS: Vitamin D's pleiotropic effects include immune modulation, and its supplementation has been shown to prevent respiratory tract infections. The effectivity of vitamin D as a therapeutic intervention in critical illness remains less defined. The current study analyzed clinical and immunologic effects of vitamin D levels in patients suffering from coronavirus disease 2019 (COVID-19) induced acute respiratory distress syndrome (ARDS). METHODS: This was a single-center retrospective study in patients receiving intensive care with a confirmed SARS-CoV-2 infection and COVID-19 ARDS. 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D serum levels, pro- and anti-inflammatory cytokines and immune cell subsets were measured on admission as well as after 10-15 days. Clinical parameters were extracted from the patient data management system. Standard operating procedures included the daily administration of vitamin D3 via enteral feeding. RESULTS: A total of 39 patients with COVID-19 ARDS were eligible, of which 26 were included in this study as data on vitamin D status was available. 96% suffered from severe COVID-19 ARDS. All patients without prior vitamin D supplementation (n = 22) had deficient serum levels of 25-hydroxyvitamin D. Vitamin D supplementation resulted in higher serum levels of 25-hydroxyvitamin D but not did not increase 1,25-dihydroxyvitamin D levels after 10-15 days. Clinical parameters did not differ between patients with sufficient or deficient levels of 25-hydroxyvitamin D. Only circulating plasmablasts were higher in patients with 25-hydroxyvitamin D levels ≥30 ng/ml (p = 0.029). Patients with 1,25-dihydroxyvitamin D levels below 20 pg/ml required longer mechanical ventilation (p = 0.045) and had a worse acute physiology and chronic health evaluation (APACHE) II score (p = 0.048). CONCLUSION: The vast majority of COVID-19 ARDS patients had vitamin D deficiency. 25-hydroxyvitamin D status was not related to changes in clinical course, whereas low levels of 1,25-dihydroxyvitamin D were associated with prolonged mechanical ventilation and a worse APACHE II score.

[Update on PONV-What is new in prophylaxis and treatment of postoperative nausea and vomiting? : Summary of recent consensus recommendations and Cochrane reviews on prophylaxis and treatment of postoperative nausea and vomiting]. / Update PONV ­ Was gibt es Neues bei der Prophylaxe und Therapie von postoperativer Übelkeit und postoperativem Erbrechen? : Zusammenfassung rezenter Konsensusempfehlungen sowie Cochrane-Reviews zu Prophylaxe und Therapie postoperativer Übelkeit und postoperativen Erbrechens.

The prophylaxis and treatment of postoperative pain to enhance patient comfort has been a primary goal of anesthesiologists for the last decades; however, avoiding postoperative nausea and vomiting (PONV) is, from a patient's perspective, a highly relevant and equally important goal of anesthesia. Recent consensus-based guidelines suggest the assessment of risk factors including female gender, postoperative opioid administration, non-smoking status, a history of PONV or motion sickness, young patient age, longer duration of anesthesia, volatile anesthetics and the type of surgery and reducing the patient's baseline risk (e.g. through the use of regional anesthesia and administration of non-opioid analgesics as part of a multimodal approach). In general, a liberal PONV prophylaxis is encouraged for adult patients and children, which should also be administered when no risk assessment is made. The basis for every adult patient should be a standard prophylaxis with two antiemetics, such as dexamethasone in combination with a 5-HT3 receptor antagonist. In patients at high risk, this should be supplemented by a third and potentially a fourth antiemetic prophylaxis with a different mechanism of action. A recently published comprehensive Cochrane meta-analysis comparing available antiemetic prophylaxes reported the highest effectiveness to prevent PONV for the NK1 receptor antagonist aprepitant (relative risk, RR 0.26), followed by ramosetron (RR 0.44), granisetron (RR 0.45), dexamethasone (RR 0.51) and ondansetron (RR 0.55), thereby revising the dogma that every antiemetic is equally effective. Adverse events of antiemetics were generally rare and reported in less than half of the included studies, yielding a low quality of evidence for these end points. In general, combinations of different antiemetics were more effective than single prophylaxes. In children above 3 years of age, the same principles should be applied as in adults. For these patients, there is a high degree of evidence for the combination of dexamethasone and 5­HT3 receptor antagonists. When PONV occurs, the consensus guidelines suggest that antiemetics from a class different than given as prophylaxis should be administered. To decrease the incidence of PONV and increase the quality of care, the importance of the implementation of institutional-level guidelines and protocols as well as assessment of PONV prophylaxis and PONV incidence is highly recommended.

[COVID-19 in obstetric anesthesia : Prospective surveillance of peripartum infections with SARS-CoV-2 and peripartum course of disease in affected women]. / COVID-19 in der geburtshilflichen Anästhesie : Prospektive Erfassung von SARS-CoV-2-Infektionen zum Zeitpunkt der Geburt sowie des peripartalen Verlaufs SARS-CoV-2-positiver Schwangerer.

BACKGROUND: In the current pandemic regarding the infection with the SARS-CoV-2-virus and COVID-19 as the disease, concerns about pregnant women, effects on childbirth and the health of the newborn remain high. Initially, due to the early manifestation of the disease in younger patients, high numbers of COVID-19 patients in women needing peripartum care were expected. OBJECTIVE: This article aims to provide a general overview over the beginning of the pandemic as well as the second wave of infections in Germany and Switzerland, regarding SARS-CoV­2 positive pregnant women hospitalized for childbirth. We therefore launched a registry to gain timely information over the dynamic situation during the SARS-CoV­2 pandemic in Germany. MATERIAL AND METHODS: As part of the COVID-19-related Obstetric Anesthesia Longitudinal Assessment (COALA) registry, centers reported weekly birth rates, numbers of suspected SARS-CoV­2 cases, as well as the numbers of confirmed cases between 16 March and 3 May 2020. Data acquisition was continued from 18 October 2020 till 28 February 2021. The data were analyzed regarding distribution of SARS-CoV­2 positive pregnant women hospitalized for childbirth between centers, calendar weeks and birth rates as well as maternal characteristics, course of disease and outcomes of SARS-CoV­2 positive pregnant women. RESULTS: A total of 9 German centers reported 2270 deliveries over 7 weeks during the first wave of infections including 3 SARS-CoV­2 positive cases and 9 suspected cases. During the second survey period, 6 centers from Germany and Switzerland reported 41 positive cases out of 4897 deliveries. One woman presented with a severe and ultimately fatal course of the disease, while another one needed prolonged ECMO treatment. Of the women 28 presented with asymptomatic infections and 6 neonates were admitted to a neonatal intensive care unit for further treatment. There was one case of neonatal SARS-CoV­2 infection. CONCLUSION: The number of pregnant women infected with SARS-CoV­2 was at a very low level at the time of delivery, with only sporadic suspected or confirmed cases. Due to the lack of comprehensive testing in the first survey period, however, a certain number of asymptomatic cases are to be assumed. Of the cases 68% presented as asymptomatic or as mild courses of disease but the data showed that even in young healthy patients without the presence of typical risk factors, serious progression can occur. These outcomes should raise awareness for anesthesiologists, obstetricians, pediatricians and intensive care physicians to identify severe cases of COVID-19 in pregnant women during childbirth and to take the necessary precautions to ensure the best treatment of mother and neonate. The prospective acquisition of data allowed a timely assessment of the highly dynamic situation and gain knowledge regarding this vulnerable group of patients.

Trial registration and selective outcome reporting in 585 clinical trials investigating drugs for prevention of postoperative nausea and vomiting.

BACKGROUND: Selective outcome reporting in clinical trials introduces bias in the body of evidence distorting clinical decision making. Trial registration aims to prevent this bias and is suggested by the International Committee of Medical Journal Editors (ICMJE) since 2004. METHODS: The 585 randomized controlled trials (RCTs) published between 1965 and 2017 that were included in a recently published Cochrane review on antiemetic drugs for prevention of postoperative nausea and vomiting were selected. In a retrospective study, we assessed trial registration and selective outcome reporting by comparing study publications with their registered protocols according to the 'Cochrane Risk of bias' assessment tool 1.0. RESULTS: In the Cochrane review, the first study which referred to a registered trial protocol was published in 2004. Of all 585 trials included in the Cochrane review, 334 RCTs were published in 2004 or later, of which only 22% (75/334) were registered. Among the registered trials, 36% (27/75) were pro- and 64% (48/75) were retrospectively registered. 41% (11/27) of the prospectively registered trials were free of selective outcome reporting bias, 22% (6/27) were incompletely registered and assessed as unclear risk, and 37% (10/27) were assessed as high risk. Major outcome discrepancies between registered and published high risk trials were a change from the registered primary to a published secondary outcome (32%), a new primary outcome (26%), and different outcome assessment times (26%). Among trials with high risk of selective outcome reporting 80% favoured at least one statistically significant result. Registered trials were assessed more often as 'overall low risk of bias' compared to non-registered trials (64% vs 28%). CONCLUSIONS: In 2017, 13 years after the ICMJE declared prospective protocol registration a necessity for reliable clinical studies, the frequency and quality of trial registration in the field of PONV is very poor. Selective outcome reporting reduces trustworthiness in findings of clinical trials. Investigators and clinicians should be aware that only following a properly registered protocol and transparently reporting of predefined outcomes, regardless of the direction and significance of the result, will ultimately strengthen the body of evidence in the field of PONV research in the future.

Intraoperative management of combined general anesthesia and thoracic epidural analgesia: A survey among German anesthetists.

BACKGROUND: Evidence concerning combined general anesthesia (GA) and thoracic epidural analgesia (EA) is controversial and the procedure appears heterogeneous in clinical implementation. We aimed to gain an overview of different approaches and to unveil a suspected heterogeneity concerning the intraoperative management of combined GA and EA. METHODS: This was an anonymous survey among Members of the Scientific working group for regional anesthesia within the German Society of Anaesthesiology and Intensive Care Medicine (DGAI) conducted from February 2020 to August 2020. RESULTS: The response rate was 38%. The majority of participants were experienced anesthetists with high expertise for the specific regimen of combined GA and EA. Most participants establish EA in the sitting position (94%), prefer early epidural initiation (prior to skin incision: 80%; intraoperative: 14%) and administer ropivacaine (89%) in rather low concentrations (0.2%: 45%; 0.375%: 30%; 0.75%: 15%) mostly with an opioid (84%) in a bolus-based mode (95%). The majority reduce systemic opioid doses intraoperatively if EA works sufficiently (minimal systemic opioids: 58%; analgesia exclusively via EA: 34%). About 85% manage intraoperative EA insufficiency with systemic opioids, 52% try to escalate EA, and only 25% use non-opioids, e.g. intravenous ketamine or lidocaine. CONCLUSIONS: Although, consensus seems to be present for several aspects (patient's position during epidural puncture, main epidural substance, application mode), there is considerable heterogeneity regarding systemic opioids, rescue strategies for insufficient EA, and hemodynamic management, which might explain inconsistent results of previous trials and meta-analyses.

Clinical Significance of Micronutrient Supplementation in Critically Ill COVID-19 Patients with Severe ARDS.

The interplay between inflammation and oxidative stress is a vicious circle, potentially resulting in organ damage. Essential micronutrients such as selenium (Se) and zinc (Zn) support anti-oxidative defense systems and are commonly depleted in severe disease. This single-center retrospective study investigated micronutrient levels under Se and Zn supplementation in critically ill patients with COVID-19 induced acute respiratory distress syndrome (ARDS) and explored potential relationships with immunological and clinical parameters. According to intensive care unit (ICU) standard operating procedures, patients received 1.0 mg of intravenous Se daily on top of artificial nutrition, which contained various amounts of Se and Zn. Micronutrients, inflammatory cytokines, lymphocyte subsets and clinical data were extracted from the patient data management system on admission and after 10 to 14 days of treatment. Forty-six patients were screened for eligibility and 22 patients were included in the study. Twenty-one patients (95%) suffered from severe ARDS and 14 patients (64%) survived to ICU discharge. On admission, the majority of patients had low Se status biomarkers and Zn levels, along with elevated inflammatory parameters. Se supplementation significantly elevated Se (p = 0.027) and selenoprotein P levels (SELENOP; p = 0.016) to normal range. Accordingly, glutathione peroxidase 3 (GPx3) activity increased over time (p = 0.021). Se biomarkers, most notably SELENOP, were inversely correlated with CRP (rs = -0.495), PCT (rs = -0.413), IL-6 (rs = -0.429), IL-1ß (rs = -0.440) and IL-10 (rs = -0.461). Positive associations were found for CD8+ T cells (rs = 0.636), NK cells (rs = 0.772), total IgG (rs = 0.493) and PaO2/FiO2 ratios (rs = 0.504). In addition, survivors tended to have higher Se levels after 10 to 14 days compared to non-survivors (p = 0.075). Sufficient Se and Zn levels may potentially be of clinical significance for an adequate immune response in critically ill patients with severe COVID-19 ARDS.

Point of care diagnostic of hypercoagulability and platelet function in COVID-19 induced acute respiratory distress syndrome: a retrospective observational study.

BACKGROUND: Coronavirus disease 2019 (COVID-19) associated coagulopathy (CAC) leads to thromboembolic events in a high number of critically ill COVID-19 patients. However, specific diagnostic or therapeutic algorithms for CAC have not been established. In the current study, we analyzed coagulation abnormalities with point-of-care testing (POCT) and their relation to hemostatic complications in patients suffering from COVID-19 induced Acute Respiratory Distress Syndrome (ARDS). Our hypothesis was that specific diagnostic patterns can be identified in patients with COVID-19 induced ARDS at risk of thromboembolic complications utilizing POCT. METHODS: This is a single-center, retrospective observational study. Longitudinal data from 247 rotational thromboelastometries (Rotem®) and 165 impedance aggregometries (Multiplate®) were analysed in 18 patients consecutively admitted to the ICU with a COVID-19 induced ARDS between March 12th to June 30th, 2020. RESULTS: Median age was 61 years (IQR: 51-69). Median PaO2/FiO2 on admission was 122 mmHg (IQR: 87-189), indicating moderate to severe ARDS. Any form of hemostatic complication occurred in 78 % of the patients with deep vein/arm thrombosis in 39 %, pulmonary embolism in 22 %, and major bleeding in 17 %. In Rotem® elevated A10 and maximum clot firmness (MCF) indicated higher clot strength. The delta between EXTEM A10 minus FIBTEM A10 (ΔA10) > 30 mm, depicting the sole platelet-part of clot firmness, was associated with a higher risk of thromboembolic events (OD: 3.7; 95 %CI 1.3-10.3; p = 0.02). Multiplate® aggregometry showed hypoactive platelet function. There was no correlation between single Rotem® and Multiplate® parameters at intensive care unit (ICU) admission and thromboembolic or bleeding complications. CONCLUSIONS: Rotem® and Multiplate® results indicate hypercoagulability and hypoactive platelet dysfunction in COVID-19 induced ARDS but were all in all poorly related to hemostatic complications..

Current concepts in the evaluation and management of preoperative anemia.

PURPOSE OF REVIEW: In the past years, patient blood management (PBM) has evolved to improve patient's care and safety. Anemia is one of the most common medical diseases in the world and is an independent risk factor for morbidity and mortality. Iron deficiency is the main cause for anemia and constitutes a potentially preventable condition with a great impact on surgical outcome. However, preoperative anemia management is not yet established in most hospitals. Changing workflows and re-thinking is challenging. Numerous published studies confirmed the positive effect of preoperative anemia diagnosis and treatment recently. RECENT FINDINGS: Iron supplementation in iron-deficient anemic (IDA) patients reduce the need for allogenic blood transfusion thereby improving perioperative outcome. SUMMARY: Since the introduction of PBM programs, important movements towards early detection and therapy of preoperative anemia have been observed. However, preoperative anemia management is not implemented on a large scale as many healthcare professionals are not aware of the most recent findings in the field. Preoperative anemia management, particularly iron supplementation in IDA patients, has proven to be highly effective and has a tremendous effect on patient safety and outcome.

Drugs in anesthesia: preventing postoperative nausea and vomiting.

PURPOSE OF REVIEW: Postoperative nausea and vomiting (PONV) continues to be a burden for patients, medical staff and healthcare facilities because of inadequate adherence to available recommendations. This review gives an overview on recent recommendations, new evidence and remaining issues in the field of PONV management. RECENT FINDINGS: A wide range of drugs is available for the management of PONV including corticosteroids, 5-HT3-antagonists, dopamine-antagonists, neurokinin-receptor-1 (NK1)-antagonists, antihistamines and anticholinergics. The updated PONV guidelines from 2020 recommend a universal multimodal strategy for PONV prophylaxis, which is an important paradigm shift to improve implementation of the existing evidence. A recent Cochrane network meta-analysis ranked single drugs and drug combinations for PONV prophylaxis in terms of efficacy and safety. Notably, NK1-antagonists and new 5-HT3-antagonists ranged among the most effective drugs. However, safety data on antiemetics are generally scarce. SUMMARY: Numerous drug (combinations) and strategies are available for PONV management. New and very effective (single) drugs could result in a simplification compared with a combination of several drugs, and thus lead to better implementation.

Drugs for preventing postoperative nausea and vomiting in adults after general anesthesia: An abridged Cochrane network meta-analysis.

OBJECTIVE: In this abridged version of the recently published Cochrane review on antiemetic drugs, we summarize its most important findings and discuss the challenges and the time needed to prepare what is now the largest Cochrane review with network meta-analysis in terms of the number of included studies and pages in its full printed form. METHODS: We conducted a systematic review with network meta-analyses to compare and rank single antiemetic drugs and their combinations belonging to 5HT3-, D2-, NK1-receptor antagonists, corticosteroids, antihistamines, and anticholinergics used to prevent postoperative nausea and vomiting in adults after general anesthesia. RESULTS: 585 studies (97 516 participants) testing 44 single drugs and 51 drug combinations were included. The studies' overall risk of bias was assessed as low in only 27% of the studies. In 282 studies, 29 out of 36 drug combinations and 10 out of 28 single drugs lowered the risk of vomiting at least 20% compared to placebo. In the ranking of treatments, combinations of drugs were generally more effective than single drugs. Single NK1 receptor antagonists were as effective as other drug combinations. Of the 10 effective single drugs, certainty of evidence was high for aprepitant, ramosetron, granisetron, dexamethasone, and ondansetron, while moderate for fosaprepitant and droperidol. For serious adverse events (SAEs), any adverse event (AE), and drug-class specific side effects evidence for intervention effects was mostly not convincing. CONCLUSIONS: There is high or moderate evidence for at least seven single drugs preventing postoperative vomiting. However, there is still considerable lack of evidence regarding safety aspects that does warrant investigation.

COVID-19 and the kidney: A retrospective analysis of 37 critically ill patients using machine learning.

INTRODUCTION: There is evidence that SARS-CoV2 has a particular affinity for kidney tissue and is often associated with kidney failure. METHODS: We assessed whether proteinuria can be predictive of kidney failure, the development of chronic kidney disease, and mortality in 37 critically ill COVID-19 patients. We used machine learning (ML) methods as decision trees and cut-off points created by the OneR package to add new aspects, even in smaller cohorts. RESULTS: Among a total of 37 patients, 24 suffered higher-grade renal failure, 20 of whom required kidney replacement therapy. More than 40% of patients remained on hemodialysis after intensive care unit discharge or died (27%). Due to frequent anuria proteinuria measured in two-thirds of the patients, it was not predictive for the investigated endpoints; albuminuria was higher in patients with AKI 3, but the difference was not significant. ML found cut-off points of >31.4 kg/m2 for BMI and >69 years for age, constructed decision trees with great accuracy, and identified highly predictive variables for outcome and remaining chronic kidney disease. CONCLUSIONS: Different ML methods and their clinical application, especially decision trees, can provide valuable support for clinical decisions. Presence of proteinuria was not predictive of CKD or AKI and should be confirmed in a larger cohort.

Association of Intravenous Tranexamic Acid With Thromboembolic Events and Mortality: A Systematic Review, Meta-analysis, and Meta-regression.

IMPORTANCE: Tranexamic acid (TXA) is an efficient antifibrinolytic agent; however, concerns remain about the potential adverse effects, particularly vascular occlusive events, that may be associated with its use. OBJECTIVE: To examine the association between intravenous TXA and total thromboembolic events (TEs) and mortality in patients of all ages and of any medical disciplines. DATA SOURCE: Cochrane Central Register of Controlled Trials and MEDLINE were searched for eligible studies investigating intravenous TXA and postinterventional outcome published between 1976 and 2020. STUDY SELECTION: Randomized clinical trials comparing intravenous TXA with placebo/no treatment. The electronic database search yielded a total of 782 studies, and 381 were considered for full-text review. Included studies were published in English, German, French, and Spanish. Studies with only oral or topical tranexamic administration were excluded. DATA EXTRACTION AND SYNTHESIS: Meta-analysis, subgroup and sensitivity analysis, and meta-regression were performed. This study followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline. MAIN OUTCOMES AND MEASURES: Vascular occlusive events and mortality. RESULTS: A total of 216 eligible trials including 125 550 patients were analyzed. Total TEs were found in 1020 (2.1%) in the group receiving TXA and 900 (2.0%) in the control group. This study found no association between TXA and risk for total TEs (risk difference = 0.001; 95% CI, -0.001 to 0.002; P = .49) for venous thrombosis, pulmonary embolism, venous TEs, myocardial infarction or ischemia, and cerebral infarction or ischemia. Sensitivity analysis using the risk ratio as an effect measure with (risk ratio = 1.02; 95% CI, 0.94-1.11; P = .56) and without (risk ratio = 1.03; 95% CI, 0.95-1.12; P = .52) studies with double-zero events revealed robust effect size estimates. Sensitivity analysis with studies judged at low risk for selection bias showed similar results. Administration of TXA was associated with a significant reduction in overall mortality and bleeding mortality but not with nonbleeding mortality. In addition, an increased risk for vascular occlusive events was not found in studies including patients with a history of thromboembolism. Comparison of studies with sample sizes of less than or equal to 99 (risk difference = 0.004; 95% CI, -0.006 to 0.014; P = .40), 100 to 999 (risk difference = 0.004; 95% CI, -0.003 to 0.011; P = .26), and greater than or equal to 1000 (risk difference = -0.001; 95% CI, -0.003 to 0.001; P = .44) showed no association between TXA and incidence of total TEs. Meta-regression of 143 intervention groups showed no association between TXA dosing and risk for venous TEs (risk difference, -0.005; 95% CI, -0.021 to 0.011; P = .53). CONCLUSIONS AND RELEVANCE: Findings from this systematic review and meta-analysis of 216 studies suggested that intravenous TXA, irrespective of dosing, is not associated with increased risk of any TE. These results help clarify the incidence of adverse events associated with administration of intravenous TXA and suggest that TXA is safe for use with undetermined utility for patients receiving neurological care.