Regional antibiotic delivery for sternal wound infection prophylaxis a systematic review and meta-analysis of randomized controlled trials.

Despite evidence suggesting the benefit of prophylactic regional antibiotic delivery (RAD) to sternal edges during cardiac surgery, it is seldom performed in clinical practice. The value of topical vancomycin and gentamicin for sternal wound infections (SWI) prophylaxis was further questioned by recent studies including randomized controlled trials (RCTs). The aim of this systematic review and meta-analysis was to comprehensively assess the safety and effectiveness of RAD to reduce the risk of SWI.We screened multiple databases for RCTs assessing the effectiveness of RAD (vancomycin, gentamicin) in SWI prophylaxis. Random effects meta-analysis was performed. The primary endpoint was any SWI; other wound complications were also analysed. Odds Ratios served as the primary statistical analyses. Trial sequential analysis (TSA) was performed.Thirteen RCTs (N = 7,719 patients) were included. The odds of any SWI were significantly reduced by over 50% with any RAD: OR (95%CIs): 0.49 (0.35-0.68); p < 0.001 and consistently reduced in vancomycin (0.34 [0.18-0.64]; p < 0.001) and gentamicin (0.58 [0.39-0.86]; p = 0.007) groups (psubgroup = 0.15). Similarly, RAD reduced the odds of SWI in diabetic and non-diabetic patients (0.46 [0.32-0.65]; p < 0.001 and 0.60 [0.44-0.83]; p = 0.002 respectively). Cumulative Z-curve passed the TSA-adjusted boundary for SWIs suggesting adequate power has been met and no further trials are needed. RAD significantly reduced deep (0.60 [0.43-0.83]; p = 0.003) and superficial SWIs (0.54 [0.32-0.91]; p = 0.02). No differences were seen in mediastinitis and mortality, however, limited number of studies assessed these endpoints. There was no evidence of systemic toxicity, sternal dehiscence and resistant strains emergence. Both vancomycin and gentamicin reduced the odds of cultures outside their respective serum concentrations' activity: vancomycin against gram-negative strains: 0.20 (0.01-4.18) and gentamicin against gram-positive strains: 0.42 (0.28-0.62); P < 0.001. Regional antibiotic delivery is safe and effectively reduces the risk of SWI in cardiac surgery patients.

10-Year Mortality of Off-Pump Versus On-Pump Coronary Artery Bypass Grafting: An Updated Systematic Review, Meta-Analysis, and Meta-Regression.

The longstanding debate on off-pump coronary artery bypass grafting (OPCAB) versus on-pump coronary artery bypass grafting (ONCAB) has primarily focused on short-term and mid-term outcomes, with limited attention to long-term survival. This study aims to address this gap by providing an updated analysis of 10-year mortality rates after OPCAB versus ONCAB. We have conducted a systematic review and meta-analysis, incorporating 22 studies comprising 69,449 patients. The primary end point was all-cause mortality at 10 years. Meta-regression analysis explored sources of heterogeneity. The meta-analysis revealed no significant difference in long-term all-cause mortality between OPCAB and ONCAB (hazard ratio 1.000, 95% confidence interval 0.92 to 1.08, p = 0.95). Although substantial heterogeneity existed across studies, meta-regression identified older age as a significant factor favoring OPCAB. However, patient characteristics like gender, co-morbidities, and graft numbers did not significantly influence the choice of surgical technique. In conclusion, this study challenges historical concerns regarding OPCAB's quality of revascularization and long-term survival demonstrating comparable outcomes to ONCAB in well-selected patients when performed by experienced surgeons. The results emphasize the importance of surgeon proficiency and advocate for recognizing surgical revascularization as a subspecialty.

Dual-Antiplatelet Therapy After Coronary Artery Bypass Grafting: A Survey of UK Cardiac Surgeons.

OBJECTIVE: Antiplatelet therapy after coronary artery bypass grafting (CABG) is important in postoperative medical management. Although cardiac surgeons are well-versed in the guidelines regarding discontinuation of dual-antiplatelet therapy (DAPT; aspirin and a P2Y12 antagonist) before CABG to minimize bleeding risk, there is considerable variability in DAPT dosing after CABG. The objective of this study was to explore the current trends in DAPT after CABG in the UK to improve understanding of the existing practice. DESIGN: This study used an online survey with 9 questions about the use of DAPT after CABG. An invitation to participate was sent to all adult cardiac surgeons currently in practice in the UK and the Republic of Ireland. SETTING: The study was conducted in the UK and the Republic of Ireland. PARTICIPANTS: Participants in this study were adult cardiac surgeons currently in practice in the UK and the Republic of Ireland. INTERVENTIONS: There were no interventions in this study. MEASUREMENTS AND MAIN RESULTS: Responses were received from across the UK (85.4% UK; 4% each from Scotland and Northern Ireland, 1.3% from Wales) and 5.3% from the Republic of Ireland. Fifty-seven percent of the respondents performed between 50 and 100 CABGs per year. Ninety-one percent of the respondents prescribe DAPT postoperatively, but the choice of which patients receive it varied. Most responding surgeons used DAPT for selective patient cohorts, such as those with acute coronary syndrome (51%), diffuse coronary artery disease (42%), perioperative myocardial infarction (36%), coronary endarterectomy (31%), or when bypassing a stented coronary artery (23%). Thirty-eight percent of the respondents began all their patients with CABGs on DAPT. The most preferred P2Y12 antagonist was clopidogrel, used by 75% of respondents and introduced on day 1 after surgical revascularization (71%). The routine duration for DAPT is 12 months, which 78% of the respondents preferred. The main reason for not starting DAPT in those surveyed was the bleeding risk associated with DAPT (72%). CONCLUSIONS: The survey uncovered variation in the use of DAPT after CABG. However, DAPT remains the preferred strategy after CABG in the UK. The study highlighted the need to develop standardized protocols for DAPT after CABG.

Antiplatelet Resistance in Patients Who Underwent Coronary Artery Bypass Grafting: A Systematic Review and Meta-Analysis.

Antiplatelet therapy (APT) with aspirin and a P2Y12 inhibitor is commonly given to patients who underwent coronary artery bypass grafting (CABG) to reduce thrombotic events. APT resistance, the inadequate antiplatelet effect of these drugs, is a growing concern. This review aimed to assess APT resistance prevalence in patients who underwent CABG and its impact on clinical outcomes. We conducted a comprehensive search for relevant studies published to date. The included studies measured platelet function through laboratory assays and reported on clinical outcomes in patients who underwent CABG. The primary outcomes were major adverse cardiovascular events (MACEs) and mortality, whereas the secondary outcomes included acute coronary syndrome (ACS), stroke, and thromboembolic events. The meta-analysis used random-effects models, with heterogeneity assessed using the I2 statistic. The initial search identified 45 studies, with 11 meeting the inclusion criteria, involving 3,122 patients. The overall prevalence of APT resistance in patients who underwent CABG was 39%. Patients with APT resistance had significantly higher risks of MACEs and death (odds ratio [OR] 1.73, 95% confidence interval [CI] 1.06 to 2.83, p = 0.03) and postoperative myocardial infarction (OR 2.25, 95% CI 1.13 to 4.48, p = 0.02) than those without resistance. However, no significant association was found between APT resistance and stroke (OR 2.25, 95% CI 0.80 to 6.35, p = 0.12) or other thromboembolic events (OR 1.72, 95% CI 0.72 to 4.08, p = 0.22). In conclusion, APT resistance is prevalent in a significant proportion of patients who underwent CABG, increasing the risk of MACEs and postoperative myocardial infarction. These findings emphasize the need for further research to develop tailored antiplatelet strategies in this patient population.

Topical vancomycin for sternal wound infection prophylaxis. A systematic review and updated meta-analysis of over 40,000 cardiac surgery patients.

BACKGROUND: Despite guideline recommendations, routine application of topical antibiotic agents to sternal edges after cardiac surgery is seldom done. Recent randomized controlled trials have also questioned the effectiveness of topical vancomycin in sternal wound infection prophylaxis. METHODS: We screened multiple databases for observational studies and randomized controlled trials assessing the effectiveness of topical vancomycin. Random effects meta-analysis and risk-profile regression were performed, and randomized controlled trials and observational studies were analyzed separately. The primary endpoint was sternal wound infection; other wound complications were also analyzed. Risk ratios served as primary statistics. RESULTS: Twenty studies (N = 40,871) were included, of which 7 were randomized controlled trials (N = 2,187). The risk of sternal wound infection was significantly reduced by almost 70% in the topical vancomycin group (risk ratios [95% confidence intervals]: 0.31 (0.23-0.43); P < .00001) and was comparable between randomized controlled trials (0.37 [0.21-0.64]; P < .0001) and observational studies (0.30 [0.20-0.45]; P < .00001; Psubgroup = .57). Topical vancomycin significantly reduced the risk of superficial sternal wound infections (0.29 [0.15-0.53]; P < .00001) and deep sternal wound infections (0.29 [0.19-0.44]; P < .00001). A reduction in the risk of mediastinitis and sternal dehiscence risks was also demonstrated. Risk profile meta-regression showed a significant relationship between a higher risk of sternal wound infection and a higher benefit accrued with topical vancomycin (ß-coeff. = -0.00837; P < .0001). The number needed to treat was 58.2. A significant benefit was observed in patients with diabetes mellitus (risk ratios 0.21 [0.11-0.39]; P < .00001). There was no evidence of vancomycin or methicillin resistance; on the contrary, the risk of gram-negative cultures was reduced by over 60% (risk ratios 0.38 [0.22-0.66]; P = .0006). CONCLUSION: Topical vancomycin effectively reduces the risk of sternal wound infection in cardiac surgery patients.

Use of Preoperative Natriuretic Peptide in Predicting Mortality After Coronary Artery Bypass Grafting: A Systematic Review and Meta-analysis.

The objective of this systematic review was to evaluate the current evidence on the utility of preoperative B-type natriuretic peptide (BNP) and N-terminal-pro B-type natriuretic peptide (NT-proBNP) in predicting short-term and long-term mortality after coronary artery bypass grafting (CABG). OVID MEDLINE, EMBASE, SCOPUS, and PUBMED were searched from 1946 to August 2022 using the following terms: "coronary artery bypass grafting" and "BNP" and "outcomes." Eligible studies included observational studies reporting the association between preoperative BNP and NT-proBNP levels and short- and long-term mortality after CABG. Articles were selected systematically, assessed for bias, and, when possible, meta-analyzed using a random effect model. After retrieving 53 articles, 11 were included for qualitative synthesis and 4 for quantitative meta-analysis. Studies included in this review showed that elevated preoperative natriuretic peptide levels, despite variable cut-offs, have been consistently shown to be associated with short- and long-term mortality after CABG. The median BNP cut-off value was 145.5 pg/mL (25th-75th percentile 95-324.25 pg/mL), and the mean NT-proBNP value was 765 ± 372 pg/mL. Compared to patients with normal natriuretic peptide levels, patients with elevated BNP and NT-proBNP presented higher mortality rates after CABG (odds ratio 3.96, 95% confidence interval 2.41-6.52; p < 0.00001). Preoperative BNP level is a powerful predictor of mortality in patients undergoing CABG. The measurement of BNP can add significant value to these patients' risk stratification and therapeutic decision-making.

Concomitant cardiac surgery and fixation of bilateral rib fractures sustained during cardiopulmonary resuscitation.

BACKGROUND: Chest compressions during cardiopulmonary resuscitation (CPR) may cause sternal or rib fractures and chest wall instability. This can complicate medical management and significantly impair respiratory function. Surgical management of flail chest is technically demanding, and it becomes even more challenging if the patient requires a concomitant cardiac procedure. CASE PRESENTATION: A 78-year-old male suffered a cardiac arrest and sustained sternal and bilateral rib fractures during a successful CPR. He underwent a concomitant coronary artery bypass grafting and aortic valve replacement combined with stabilization of the chest wall. We discuss the possibility of fixation of bilateral rib fractures and its role in postoperative recovery after cardiac surgery. CONCLUSIONS: Chest wall stabilization for an already fragile patient, with impaired respiratory system performance, could help improve overall outcomes, pulmonary function, weaning from mechanical ventilation, and rehabilitation. It may be used together with a cardiac procedure for a life-threatening cardiac pathology.

Are there differences in cardiothoracic surgery performed by trainees versus fully trained surgeons?

OBJECTIVES: We sought to assess the safety of training in cardiothoracic surgery comparing outcomes of cases performed by trainees versus fully trained surgeons. METHODS: EmBase, Scopus, PubMed, and OVID MEDLINE were searched in August 2021 independently by two authors. A third author arbitrated decisions to resolve disagreements. Inclusion criteria were articles on cardiothoracic surgery reporting on outcomes for trainees. Studies were assessed for appropriateness as per CBEM criteria. Eight hundred and ninety-two results were obtained, 27 represented best evidence (2-meta-analyses, 1-RCT, and 24 retrospective cohort studies). RESULTS: In all 474,160 operative outcomes were assessed for 434,535 coronary artery bypass grafting (CABG) (431,329 on-pump vs. 3206 off-pump), 3090 AVR, 1740 MVR/repair, 26,433 mixed, 3565 congenital, and 4797 thoracic procedures. In all 398,058 cases were performed by trainees and 75,943 by consultants. One hundred fifty-nine cases were indeterminate. There were no statistically significant differences in the patients' preoperative risk scores. All studies excluded extreme high-risk patients in emergency setting, patients with poor left ventricular function, and reoperation cases that were undertaken by consultants. There were no differences in cardiopulmonary bypass and clamp times for CABG. Times for valve replacement and repair cases were longer for trainees. There were no differences in the postoperative outcomes including perioperative myocardial infarction, resternotomy for bleeding, stroke, renal failure, intensive therapy unit length of stay, and total length of stay. One study reported no differences on angiographic graft patency at 1 year. There were no differences in in-hospital or midterm mortality out to 5-years. DISCUSSION: Trainees can perform cardiothoracic surgery in dedicated high-volume units with outcomes comparable to those of fully trained surgeons.

Simultaneous interrogation of multiple fiber Bragg grating temperature sensors using a microwave photonic approach.

In this paper, we demonstrate a microwave photonic (MWP) approach for interrogating multiple linearly chirped fiber Bragg grating (LCFBG) temperature sensors. The MWP interrogation system is based on an arrayed waveguide grating Sagnac interferometer, incorporating multiple LCFBG sensors, that is used to generate multiple chirped microwave waveforms whose characteristics are uniquely related to those of the LCFBGs. Compressing the generated microwave signals allows monitoring simultaneously and independently the shifts associated with applying temperature changes to each LCFBG in real time.

Microwave photonic filter-based interrogation system for multiple fiber Bragg grating sensors.

Fiber optic sensors based on fiber Bragg gratings (FBGs) find potential use in condition monitoring because their spectral properties change according to external environmental and/or physical factors. We propose and demonstrate a technique for interrogating multiple FBG-based sensors based on microwave photonic (MWP) filtering. In particular, we exploit the spectrum-slicing properties of two different FBG Fabry-Perot cavities to implement a double passband MWP filter. Each sensor spectrum results in a unique MWP filter passband. As temperature is applied to a sensor, the corresponding MWP filter passband will shift in frequency; we track such shifts by monitoring the detected power at a fixed radio frequency. We discuss the use of a ratiometric approach for enhancing the sensitivity and the impact of cross-talk from the MWP filter responses in terms of simultaneous multi-sensor operation. Results show that we can monitor local temperatures at two (or multiple) different locations simultaneously and independently using a single measurement system.