Role of MicroRNA-21 in Regulating Intracellular Pathways Associated With Phagocytosis in Human Macrophages: An In Vitro Study.

Introduction The efficient clearance of bacteria by macrophages is crucial for the timely resolution of inflammation. In this study, we investigated the role of microRNA-21 (miR-21)-induced phagocytosis and its intracellular signaling pathways in human macrophages in vitro. Methods Human peripheral blood mononuclear cells (PBMCs) were isolated from whole blood collected from 15 healthy volunteers. Differentiated human macrophages were incubated with lipopolysaccharide (LPS) to determine the time course of changes in phagocytic activity and miR-21 expression. The expression of candidate genes targeted by miR-21 and its downstream effectors was quantitatively assessed. The effects of miR-21 modulation were also examined via transfection with miR-21 mimics and inhibitors. Results Incubation of human macrophages with LPS upregulated both phagocytosis and miR-21 expression. Notably, changing miR-21 expression levels using miR-21 mimics or inhibitors led to significant and opposite changes in the expression of its downstream effectors. miR-21 induction in macrophages downregulated PDCD4 and PTEN, promoted the phosphorylation of Akt and the production of the anti-inflammatory cytokine IL-10, and facilitated phagocytosis. Conclusion This study directly confirms that LPS upregulates macrophage phagocytosis and miR-21 expression. Elevated miR-21 levels in macrophages enhanced phagocytosis, contributing to an anti-inflammatory phenotype. These findings underscore the importance of miR-21 in resolving inflammation.

Total Intravenous Anesthesia Using Remimazolam for Transcarotid Approach Transcatheter Aortic Valve Replacement: A Case Report.

The transcarotid approach was introduced in Japan in April 2024 as an alternative approach for transcatheter aortic valve replacement (TAVR). Because carotid artery blood flow is reduced on one side during the procedure, there is a risk of intraoperative brain stroke. Therefore, it is crucial to check for cerebral complications immediately after the procedure. We report a case involving an 87-year-old female who underwent transcarotid TAVR under general anesthesia with remimazolam and remifentanil. The operation was completed in a short period. There was no evidence of hypotension during the induction of anesthesia, and intraoperative blood pressure control was easy. However, there was a decrease in local oxygen saturation for approximately nine minutes intraoperatively. Following the administration of flumazenil, the patient was quickly awakened, and neurological findings were confirmed to be normal. The patient was discharged without complications. Our findings suggest that remimazolam, an ultra-short-acting benzodiazepine, is feasible for the transcarotid TAVR procedure due to its minimal circulatory impact and ability to facilitate rapid and reliable arousal.

Retrograde Aortic Valve Migration During Transcatheter Aortic Valve Replacement for Aortic Regurgitation: A Case Report Highlighting the Importance of Prompt Venoarterial Extracorporeal Membrane Oxygenation (VA-ECMO) Initiation.

Surgical aortic valve replacement (SAVR) is the recommended curative treatment for pure native aortic regurgitation (AR). However, some patients are not suitable for SAVR due to comorbidities or frailty. Transcatheter aortic valve replacement (TAVR) has been reported to offer a better prognosis than medical therapy in AR patients; thus, the use of TAVR for AR may increase in the future. However, the reduced calcification and annulus ring stiffness associated with TAVR may increase the risk of valve migration. Accumulating data on rescue measures in the event of valve migration is necessary. An 87-year-old female with a history of hypertension and persistent atrial fibrillation presented to our emergency department with dyspnea. The patient was diagnosed with congestive heart failure class IV, according to the New York Heart Association classification, necessitating urgent admission to our cardiac department. Due to the patient's high surgical risk (Society of Thoracic Surgeons (STS) score 9.17%, Euro2 score 9.55%, frailty 6), the heart team performed TAVR with a right femoral arterial approach. The patient was sedated, and pacing was initiated at 180 bpm. We placed an Edwards SAPIEN 3 valve (Edwards Lifesciences, Irvine, CA, USA) #23 (-1 mL volume, with attached balloon). During the post-deployment procedure, the aortic valve migrated retrogradely into the left ventricle (LV). Despite the occurrence of severe aortic valve regurgitation, the patient's vital signs remained stable. Five minutes after the migration of the aortic valve, venoarterial extracorporeal membrane oxygenation (VA-ECMO) was initiated. A second TAVR valve implantation was then performed. However, after the second valve implantation and the removal of the pre-shaped guidewire (Safari2 pre-shaped guidewire extra small, Boston Scientific, Marlborough, MA, USA), the migrated valve became stuck in the left ventricular outflow tract (LVOT) in a reverse position, resulting in severely limited left ventricular ejection. We increased the support provided by VA-ECMO, and surgical conversion to SAVR was performed without experiencing circulatory collapse. Surgical aortic valve replacement was initiated successfully, and withdrawal of the cardiopulmonary bypass (CPB) was performed without complications. The patient was extubated on the first postoperative day (POD), discharged from the ICU on POD 3, and transferred for rehabilitation on POD 27. In summary, the prompt introduction of VA-ECMO was important for avoiding complications and saving the patient's life following the retrograde migration of the TAVR valve.

Patch Dehiscence After Mitral Valve Repair by Posterior Mitral Leaflet Augmentation at Weaning From Cardiopulmonary Bypass.

The treatment for ischemic mitral regurgitation (MR) involves a combination of medical management and, in certain cases, surgical intervention. The approach depends on the severity of the condition, underlying causes, and the patient's overall health. A 76-year-old male with heart failure refractory to medical management because of ischemic MR was considered for a mitral valve repair surgery with a posterior mitral leaflet augmentation technique. Following the repair of the mitral valve and the cessation of the initial cardiopulmonary bypass (CPB), a prolapse of the posterior mitral leaflet, which had not been detected before the surgery, was revealed by intraoperative transesophageal echocardiography (TEE). A thorough inspection of the repaired mitral valve after cardiac arrest during the second CPB unveiled a loose suture at the edge of the valve and an inverted pericardium, indicating that the patch had flipped upward. Although complications of this type following the augmentation of the mitral posterior leaflet are rare, we promptly detected it using TEE, which incorporates three-dimensional imaging.

Dexmedetomidine Inhibits Hippocampal Neuronal Damage Caused by Persistent Isoflurane-Induced Hypotension in Rat Model of Chronic Cerebral Hypoperfusion.

Purpose The purpose of this study was to investigate the effect of dexmedetomidine (DEX) on hypotension-induced neuronal damage in a chronic cerebral hypoperfusion (CCH) model of rats, an established model of cerebral white matter lesions (WML) in humans, which is prevalent in the elderly and closely related to cognitive decline. Methods The CCH model rats were randomly assigned to one of four groups: normotension + no DEX (NN) group (n = 6), normotension + DEX (ND) group (n = 6), hypotension + no DEX (HN) group (n = 6), or hypotension + DEX (HD) group (n = 6). Under isoflurane anesthesia, mean arterial blood pressure was maintained at or above 80 mmHg (normotension) or below 60 mmHg (hypotension) for a duration of two hours. The DEX groups received 50 µg of DEX intraperitoneally. Two weeks later, the Y-maze test and, after preparing brain slices, immunohistochemical staining were performed using antibodies against neuronal nuclei (NeuN), microtubule-associated protein 2 (MAP2), glial fibrillary acidic protein (GFAP), and Ionized calcium-binding adapter molecule 1 (Iba1). Results Behavioral observations showed no significant differences among the groups. Significant reductions of both NeuN-positive cells and the MAP2-positive area were found in the hippocampal CA1 in the HN group compared with NN and ND groups, but not in the HD group. GFAP and Iba-1-positive areas were significantly increased in the HN group, but not in the HD group. Conclusion DEX significantly ameliorated hypotension-induced neuronal damage and both astroglial and microglial activation in the CA1 region of CCH rats.

Comparative Analysis of the Hemodynamic Effects of Remimazolam and Propofol During General Anesthesia: A Retrospective Study.

PURPOSE: Hypotension is common during anesthesia induction. However, minimal hemodynamic effects of remimazolam anesthesia have been reported. We hypothesized that remimazolam would have weaker hemodynamic effects than would propofol. To test this, we simultaneously evaluated the hemodynamics using the estimated continuous cardiac output (esCCO) system and heart rate variability (HRV) during anesthesia induction. METHODS: This was a single-center, observational, retrospective study of patients undergoing dental surgery under general anesthesia between 2020 and 2022. Seventy patients were divided into two groups: remimazolam (R group; n=34) and propofol (P group; n=36). The information obtained from the anesthesia records, patient information, esCCO system parameters, and HRV were integrated and analyzed. The percentages of various parameters were set to 100% for the pre-induction phase as the baseline. RESULTS: The %MAP (noninvasive mean arterial blood pressure) decreased over a narrower range in the R compared to the P group (-17.8% (-26.3%, -11.9%) vs. -22.6% (-32.9%, -17.0%); P=0.039). The %HR (heart rate) increased significantly in the R group and decreased in the P group (+10.7% (+6.5%, +18.6%) vs. -6.5% (-14.5%, +8.4%); P<0.01). The %SVesCCO (stroke volume calculated using the esCCO system) decreased significantly in both groups, but the R group showed a smaller difference compared to the P group (- 5.1% (-7.7%, -2.1%) vs. -10.0% (-13.8%, -5.6%); P<0.01). The rates of change in %LF nu (normalized unit of low frequency) and %HF nu (normalized unit of high frequency) were lower for the R than for the P group, although the difference was not significant (+6.8% (-14.5%, 32.4%) vs. +9.2% (-7.2%, +59.7%), P=0.30; +7.9% (-51.0%, +66.9%) vs. +22.8% (-26.1%, +61.6%), P=0.57). CONCLUSION: Remimazolam demonstrated a lower MAP reduction rate than propofol. A compensatory increase in HR occurred with a decrease in stroke volume. However, the HR increase was not attributable to the autonomic nervous system.

Remimazolam-Based Anesthesia in Patients with Heart Failure Due to Mitral Regurgitation and Low Left Ventricular Function: A Case Series.

Background and Objectives: Remimazolam is a new ultrashort-acting benzodiazepine anesthetic. Remimazolam appears to be useful in patients with severe valvular disease because of its minimal cardiovascular impact. In this retrospective case series study, we assessed the efficacy and safety of remimazolam for maintaining hemodynamic stability during anesthetic induction and maintenance. Cases: MitraClip was performed on 18 cases with severe mitral regurgitation with low left ventricular function who presented with heart failure, and remimazolam was administered for general anesthesia with induction (12 mg/kg/h) and maintenance (1 mg/kg/h). The impact of remimazolam on the hemodynamics at anesthetic induction and during anesthetic maintenance was investigated retrospectively using electronic medical records. Blood pressure decreased significantly during anesthetic induction with remimazolam (78.5 [72, 81.25] and 66.1 [62.2, 74.2], median [IQR], p = 0.0001), but only mildly, by about 10 mmHg. There was no significant change in the cardiac index (2.0 [1.8, 2.4] vs. 1.9 [1.8, 2.3], p = 0.57642) or pulse rate (73.5 ± 8.85 vs. 74.7 ± 11.7, mean ± SD, p = 0.0876) during anesthetic induction with remimazolam. All patients underwent MitraClip without major hemodynamic concerns, with no or small increases in inotropes. Conclusions: Remimazolam may be used safely in patients with severe mitral regurgitation and low left ventricular function presenting with heart failure.

A retrospective comparative study of anesthesia with remimazolam and remifentanil versus dexmedetomidine and remifentanil for transcatheter aortic valve replacement.

Remimazolam, an ultrashort-acting benzodiazepine, allows for rapid and reliable arousal. Rapid awakening using remimazolam may be beneficial in transcatheter aortic valve replacement (TAVR), as it allows rapid detection of neurologic deficits. The purpose of this study was to compare arousal time and outcomes between monitored anesthesia care (MAC) with remimazolam and remifentanil and conventional MAC with dexmedetomidine, propofol, and remifentanil. This study was a single center retrospective study. All TAVR cases performed under MAC (MAC-TAVR) at our institution between 2019 and 2021 were included. Patients were classified by anesthesia method into remimazolam and dexmedetomidine groups. Among 258 MAC-TAVR patients, 253 were enrolled. After propensity score matching, 76 patients were assigned to each group. The time from end of drug-administration to arousal [20.0 (16.0, 24.0) min vs. 38.5 (30.0, 56.3) min, p < 0.0001] and the time from attempted-arousal to arousal [1.0 (1.0, 1.0) min vs. 12.5 (3.0, 26.8) min, p < 0.0001] were significantly shorter in the remimazolam group. There was no significant difference in the length of ICU stay [2.0 (2.0, 2.0) days vs. 2.0 (2.0, 2.0) days, p = 0.157] and postoperative hospital stay [6.0 (4.0, 9.0) days vs. 5.0 (4.0, 8.0) days, p = 0.262].Trial registration: Clinical trial number: R03-123, Registry URL: https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000051635 Registration number: UMIN000045195, Principal investigator's name: Atsuhiro Kitaura, Date of registration: 20 August 2021.

Successful Nafamostat Mesilate Administration for Andexanet Alfa-Induced Heparin Resistance.

Andexanet alfa is an analog of activated factor X and is used as an antagonist of anti-activated factor X agents. Andexanet alfa is useful for hemostasis in emergent bleeding during direct oral anticoagulant administration, which contributes to safety. In patients undergoing surgery with cardiopulmonary bypass because of heparin resistance, anesthesiologists are faced with a choice of anticoagulants. Herein, we experienced anesthesia for vascular prostheses with cardiopulmonary bypass for acute aortic dissection in a patient who had received andexanet alfa preoperatively. Heparin was initially used as the anticoagulant during cardiopulmonary bypass; however, despite the administration of large doses and antithrombin III preparations, anticoagulation was insufficient. Therefore, nafamostat mesilate was administered and sufficient anticoagulation was attained. The patient completed surgery under cardiopulmonary bypass, coagulation function was recovered shortly after withdrawal, and no obvious adverse effects were observed.

Comparison of radial, dorsalis pedis, and posterior tibial arteries for ultrasound-guided arterial catheterisation with dynamic needle tip positioning in paediatric patients: a randomised controlled trial.

BACKGROUND: Arterial catheterisation in children can be challenging and time-consuming. We aimed to compare the success rates of ultrasound-guided arterial catheterisation utilising the short-axis out-of-plane approach with dynamic needle tip positioning in the radial, dorsalis pedis, and posterior tibial arteries in paediatric patients. We also examined the factors influencing the catheterisation success using dynamic needle tip positioning. METHODS: Paediatric patients (aged <3 yr) undergoing cardiac surgery were randomly assigned to three groups based on puncture sites: radial artery (Group R), dorsalis pedis artery (Group D), and posterior tibial artery (Group P). The first-attempt and overall success rates of arterial catheterisation were compared, followed by multiple logistic regression analysis (dependent variable: first-attempt success; independent variables: body weight, diameter and depth of the artery, targeted artery, and trisomy 21). RESULTS: The study included 270 subjects (n=90 per group). There was no significant difference in the first-attempt (Group R: 82%, Group D: 76%, and Group P: 81%) and overall success rates (Group R: 94%, Group D: 93%, and Group P: 91%) among the three groups. The diameter of the artery (per 0.1 mm) (odds ratio: 1.32, 95% confidence interval: 1.09-1.60) and trisomy 21 (odds ratio: 0.43, 95% confidence interval: 0.20-0.92) were independent predictors of first-attempt success or failure. CONCLUSION: The first-attempt and overall success rates of arterial catheterisation of the dorsalis pedis and posterior tibial arteries were not inferior to those in the radial artery when using dynamic needle tip positioning. These two lower extremity peripheral arteries present viable alternative catheterisation sites in paediatric patients. CLINICAL TRIAL REGISTRATION: UMIN000042847.

Two Cases of Inadequate Response to Remimazolam.

We report the inadequate efficacy of remimazolam in two patients undergoing long-term benzodiazepine analog therapy. Remimazolam is a recently developed ultrashort-acting benzodiazepine. It is primarily used as an anesthetic in surgical procedures, as it has minimal effect on cardiac function and antagonists are available. It is expected to become more widely used in the future. On the other hand, similar to other benzodiazepines, benzodiazepine tolerance can also pose a challenge with remimazolam. Herein, we report two cases who were taking long-term oral benzodiazepine analogs. One patient did not fall asleep despite a sufficient dose of remimazolam and required a change to propofol. The other patient required a high dose of remimazolam to fall asleep; however, multiple signs of arousal were noted intraoperatively. Our findings suggest that remimazolam may not be an ideal anesthetic in long-term benzodiazepine analog users. Comprehensive assessment of preoperative medications and careful monitoring of intraoperative sedation levels are necessary. Furthermore, it may be advisable to consider the use of alternative agents such as propofol.

Efficacy of perioperative prophylactic administration of corticosteroids in pediatric cardiac surgeries using cardiopulmonary bypass: a systematic review with meta-analysis.

An updated systematic review with meta-analysis comparing perioperative prophylactic administration of corticosteroids with placebo in pediatric cardiac surgeries using cardiopulmonary bypass was conducted. The Cochrane Central Register of Controlled Trials and MEDLINE (via PubMed) were searched for relevant randomized controlled trials published between January 1, 2000, and February 14, 2023. The primary outcome was postoperative in-hospital mortality. Secondary outcomes were duration of mechanical ventilation, length of intensive care unit and hospital stay, postoperative low cardiac output syndrome, and adverse events. A total of 11 studies were included in the meta-analysis. Corticosteroid administration did not decrease postoperative in-hospital mortality compared with placebo (relative risk, 0.69; 95% confidence interval, 0.40-1.17). Subgroup analyses according to the type of corticosteroids and neonates revealed that corticosteroids did not decrease postoperative in-hospital mortality. In the trial sequential analysis, the last point in the z-curve was within the futility borders. Although the duration of mechanical ventilation (mean difference, -5.54 h; 95% confidence interval (CI), -9.75 - -1.34) and incidence of low cardiac output syndrome (relative risk, 0.75; 95% CI, 0.59 - 0.96) decreased with corticosteroid administration, it did not affect the length of intensive care unit (mean difference, -0.28 days; 95% CI, -0.74 - 0.17) and hospital stay (mean difference, -0.59 days; 95% CI, -1.31 - 0.14). In conclusion, perioperative prophylactic corticosteroid administration in pediatric cardiac surgeries using cardiopulmonary bypass did not decrease postoperative in-hospital mortality compared with placebo. According to the trial sequential analysis results, additional randomized controlled trials assessing mortality are not required. PROSPERO REGISTRY NUMBER: CRD 42023391789.

Blood flow kinetic energy is a novel marker for right ventricular global systolic function in patients with left ventricular assist device therapy.

Objectives: Right ventricular (RV) failure remains a major concern in heart failure (HF) patients undergoing left ventricular assist device (LVAD) implantation. We aimed to measure the kinetic energy of blood in the RV outflow tract (KE-RVOT) - a new marker of RV global systolic function. We also aimed to assess the relationship of KE-RVOT to other echocardiographic parameters in all subjects and assess the relationship of KE-RVOT to hemodynamic parameters of RV performance in HF patients. Methods: Fifty-one subjects were prospectively enrolled into 4 groups (healthy controls, NYHA Class II, NYHA Class IV, LVAD patients) as follows: 11 healthy controls, 32 HF patients (8 NYHA Class II and 24 Class IV), and 8 patients with preexisting LVADs. The 24 Class IV HF patients included 21 pre-LVAD and 3 pre-transplant patients. Echocardiographic parameters of RV function (TAPSE, St', Et', IVA, MPI) and RV outflow color-Doppler images were recorded in all patients. Invasive hemodynamic parameters of RV function were collected in all Class IV HF patients. KE-RVOT was derived from color-Doppler imaging using a vector flow mapping proprietary software. Kruskal-Wallis test was performed for comparison of KE-RVOT in each group. Correlation between KE-RVOT and echocardiographic/hemodynamic parameters was assessed by linear regression analysis. Receiver operating characteristic curves for the ability of KE-RVOT to predict early phase RV failure were generated. Results: KE-RVOT (median ± IQR) was higher in healthy controls (55.10 [39.70 to 76.43] mW/m) than in the Class II HF group (22.23 [15.41 to 35.58] mW/m, p < 0.005). KE-RVOT was further reduced in the Class IV HF group (9.02 [5.33 to 11.94] mW/m, p < 0.05). KE-RVOT was lower in the LVAD group (25.03 [9.88 to 38.98] mW/m) than the healthy controls group (p < 0.005). KE-RVOT had significant correlation with all echocardiographic parameters and no correlation with invasive hemodynamic parameters. RV failure occurred in 12 patients who underwent LVAD implantation in the Class IV HF group (1 patient was not eligible due to death immediately after the LVAD implantation). KE-RVOT cut-off value for prediction of RV failure was 9.15 mW/m (sensitivity: 0.67, specificity: 0.75, AUC: 0.66). Conclusions: KE-RVOT, a novel noninvasive measure of RV function, strongly correlates with well-established echocardiographic markers of RV performance. KE-RVOT is the energy generated by RV wall contraction. Therefore, KE-RVOT may reflect global RV function. The utility of KE-RVOT in prediction of RV failure post LVAD implantation requires further study.

Ultrasound-Guided Short-Axis Out-of-Plane Approach With or Without Dynamic Needle-Tip Positioning for Peripheral Venous Catheterization in Pediatric Patients: A Systematic Review With Network Meta-Analysis.

OBJECTIVES: To compare the efficacy of the ultrasound-guided approach with and without dynamic needle-tip positioning and the palpation technique regarding success for peripheral venous catheterization in children. DESIGN: A systematic review with network meta-analysis. SETTING: Databases of MEDLINE (via PubMed) and Cochrane Central Register of Controlled Trials. PARTICIPANTS: Patients (<18 years) undergoing peripheral venous catheter insertion. INTERVENTIONS: Randomized clinical trials were included to compare the following techniques: the ultrasound-guided short-axis out-of-plane approach with dynamic needle-tip positioning, the approach without dynamic needle-tip positioning, and the palpation technique. MEASUREMENTS AND MAIN RESULTS: The outcomes were first-attempt and overall success rates. Eight studies were included in the qualitative analyses. According to the estimate of network comparison, dynamic needle-tip positioning was associated with higher first-attempt (risk ratio [RR] 1.67; 95% CI 1.33-2.09) and overall success rates (RR 1.25; 95% CI 1.08-1.44) than palpation. The approach without dynamic needle-tip positioning was not associated with higher first-attempt (RR 1.17; 95% CI 0.91-1.49) and overall success rates (RR 1.10; 95% CI 0.90-1.33) than palpation. Compared to the approach without dynamic needle-tip positioning, dynamic needle-tip positioning was associated with a higher first-attempt success rate (RR 1.43; 95% CI 1.07-1.92), but not a higher overall success rate (RR 1.14; 95% CI 0.92-1.41). CONCLUSIONS: Dynamic needle-tip positioning is efficacious for peripheral venous catheterization in children. It would be better to include dynamic needle-tip positioning for the ultrasound-guided short-axis out-of-plane approach.

Ultrasound-guided short-axis out-of-plane approach with or without dynamic needle tip positioning for arterial line insertion in children: A systematic review with network meta-analysis.

The efficacy of the short-axis out-of-plane (SA-OOP) approach with and without dynamic needle tip positioning (DNTP) remains unclear. This systematic review with network meta-analysis aimed to compare the success rate of arterial line insertion in children using the SA-OOP approach with and without DNTP and the palpation technique. We searched MEDLINE (via PubMed) and the Cochrane Central Register of Controlled Trials. We included randomized controlled trials that compared two of the following techniques for arterial line insertion in children: (1) the ultrasound-guided SA-OOP approach with DNTP; (2) the ultrasound-guided SA-OOP approach without DNTP; and (3) the palpation technique. A network meta-analysis was performed. The outcomes were first-attempt and overall success rates. Eight studies were finally included in this network meta-analysis. The ultrasound-guided SA-OOP approach with DNTP was associated with increased first-attempt (relative risk RR = 3.45 [95% confidence interval (CI) 2.51-4.74]) and overall success rates (RR = 1.81 [1.41-2.32]) when compared with palpation. The same approach performed without DNTP was also associated with increased first-attempt (RR = 1.96 [1.59-2.42]) and overall success rates (RR = 1.25 [1.05-1.49]) when compared with palpation. The ultrasound-guided SA-OOP approach with DNTP was associated with increased first-attempt (RR = 1.76 [1.26-2.44]) and overall success rates (RR = 1.45 [1.10-1.91]) when compared with the same approach performed without DNTP. DNTP should be performed during the ultrasound-guided SA-OOP approach for arterial line insertion in children, as this can help increase first attempt and overall success rates.

Incidence of catheter-related bloodstream infections following ultrasound-guided central venous catheterization: a systematic review and meta-analysis.

BACKGROUND: Ultrasonographic guidance is widely used for central venous catheterization. Several studies have revealed that ultrasound-guided central venous catheterization increases the rate of success during the first attempt and reduces the procedural duration when compared to the anatomical landmark-guided insertion technique, which could result in protection from infectious complications. However, the effect of ultrasound-guided central venous catheterization on catheter-related bloodstream infections remains unclear. We aimed to conduct a systematic review and meta-analysis to evaluate the value of ultrasound guidance in preventing catheter-related bloodstream infections and catheter colonization associated with central venous catheterization. METHODS: The Cochrane Central Register of Controlled Trials (CENTRAL) and MEDLINE (via PubMed) were searched up to May 9, 2022 for randomized controlled trials (RCTs) comparing ultrasound-guided and anatomical landmark-guided insertion techniques for central venous catheterization. Risk of bias was assessed using the Cochrane Risk of Bias 2 (RoB 2) tool for RCTs. A meta-analysis was performed for catheter-related bloodstream infections and catheter colonization, as primary and secondary outcomes, respectively. RESULTS: Four RCTs involving 1268 patients met the inclusion criteria and were analyzed. Ultrasound-guided central venous catheterization was associated with a slightly lower incidence of catheter-related bloodstream infections (risk ratio, 0.46; 95% confidence interval [CI], 0.16-1.32) and was not associated with a lower incidence of catheter colonization (risk ratio, 1.36; 95% CI, 0.57-3.26). CONCLUSION: Ultrasound-guided central venous catheterization might reduce the incidence of catheter-related bloodstream infections. Additional RCTs are necessary to further evaluate the value of ultrasound guidance in preventing catheter-related bloodstream infections with central venous catheterization.