Single-port robotic partial nephrectomy: impact on perioperative outcomes and hospital stay.

Single-port (SP) robotic surgery is a novel technology and is at the beginning of its adoption curve in urology. The goal of this narrative review is to provide an overview of SP-robotic partial nephrectomy (PN) 4 years after the introduction of the da Vinci SP dedicated platform, focusing on perioperative outcomes, length of stay, and surgical technique. A nonsystematic review of the literature was conducted. The research included the most updated articles that referred to SP robotic PN. Since its commercial release in 2018, several institutions have reproduced robotic PN by using the SP platform, both via a transperitoneal and a retroperitoneal approach. The published SP-robotic PN series are generally based on preliminary experiences by surgeons who had previous experience with conventional multi-arms robotic platforms. The reported outcomes are encouraging. Overall, three studies reported that SP-robotic PN cases had nonsignificantly different operative time, estimated blood loss, overall complications rate, and length of stay compared to the conventional 'multi-arms' robotic PN. However, in all these series, renal masses treated by SP had overall lower complexity. Moreover, two studies underlined decreased postoperative pain as a major pro of adopting the SP system. This should reduce/avoid the need for opioids after surgery. No study compared SP-robotic versus multi-arms robotic PN in cost-effectiveness. Published experience with SP-robotic PN has reported the feasibility and safety of the approach. Preliminary results are encouraging and at least noninferior with respect to those from the multi-arms series. Prospective comparative studies with long-term oncologic and functional results are awaited to draw more definitive conclusions and better establish the more appropriate indications of SP robotics in the field of PN.

Laparoendoscopic single-site radical nephrectomy for localized renal cancer: a descriptive research study with at least a 10-year follow-up.

Background: Laparoendoscopic single-site (LESS) surgery is performed to further narrow the incisions and reduce tissue injury. It has been more than10 years since the surgery was first described. However, there is still no report on the results of 10-year follow-up. This study evaluated the use of long-term oncology and the renal outcomes of LESS radical nephrectomy (LESS-RN) in the treatment of localized renal cancer. Methods: We retrospectively analyzed the clinical data of patients treated with LESS-RN at Changhai Hospital from 2009 to 2012. Patients with localized kidney cancer who were followed-up for at least 10 years were included in the study. The baseline data and major perioperative outcome variables were analyzed. Overall survival (OS) and cancer-specific survival (CSS) were calculated using the Kaplan-Meier method. Results: A total of 48 patients were included in the study, which had a median follow-up of 11 years (interquartile range, 10.7-11.8 years). The 10-year OS and CSS rates were 87.5% [42/48; 95% confidence interval (CI): 0.778-0.972] and 97.9% (47/48; 95% CI: 0.937-1.021), respectively. At the most recent follow-up, there were 5 patients with a chronic kidney disease stage ≥3. Among these 5 patients, 3 developed uremia and required continuous dialysis. Conclusions: For localized renal cancer, LESS-RN is safe and effective with excellent long-term oncology controllability and good functional outcomes. Prospective studies with large sample sizes need to be conducted to validate our results.

Optical weak measurement for the precise thickness determination of an ultra-thin film.

A total internal reflection system based on the weak value amplification principle is set up for the precise measurement of the thickness of an ultra-thin film. In this system, the film thickness is derived from the change of the double-peak pointer caused by the effective refractive index of the film, which is correlated to its thickness. The sensitivity and resolution of this system reached 2727.21 nm/RIU and 7.2×10-6 R I U, respectively, determined by using a sodium chloride solution with a refractive index of 1.331911. The growth process of TA/Fe(III) assembled films with thicknesses in the few nanometers range is monitored using the as-set-up system, and the experimental results are consistent with a theoretical calculation based on the Maxwell Garnett effective medium. Additionally, we theoretically calculated the detection limit for the thickness measurement of the film as 22 pm. We clearly provide a potential method for the precise measurement of the thickness of an ultra-thin film.

A comparison of perioperative outcomes between extraperitoneal robotic single-port and multiport radical prostatectomy with the da Vinci Si Surgical System.

To evaluate outcomes between extraperitoneal robotic single-port radical prostatectomy (epR-spRP) and extraperitoneal robotic multiport radical prostatectomy (epR-mpRP) performed with the da Vinci Si Surgical System, comparison was performed between 30 single-port (SP group) and 26 multiport (MP group) cases. Comparisons included operative time, estimated blood loss (EBL), hospital stay, peritoneal violation, pain scores, scar satisfaction, continence, and erectile function. The median operation time and EBL were not different between the two groups. In the SP group, the median operation time of the first 10 patients was obviously longer than that of the latter 20 patients (P < 0.001). The median postoperative hospital stay in the SP group was shorter than that in the MP group (P < 0.001). The rate of peritoneal damage in the SP group was less than that in the MP group (P = 0.017). The pain score and overall need for pain medications in the SP group were lower than those in the MP group (P < 0.001 and P = 0.015, respectively). Patients in the SP group were more satisfied with their scars than those in the MP group 3 months postoperatively (P = 0.007). At 3 months, the cancer control, recovery of erectile function, and urinary continence rates were similar between the two groups. It is safe and feasible to perform epR-spRP using the da Vinci Si surgical system. Therefore, epR-spRP can be a treatment option for localized prostate cancer. Although epR-spRP still has a learning curve, it has advantages for postoperative pain and self-assessed cosmesis. In the absence of the single-port robotic surgery platform, we can still provide minimally invasive surgery for patients.

Expression and predictive value of miR-489 and miR-21 in melanoma metastasis.

BACKGROUND: Melanoma is a highly malignant skin tumour, and is one of the most rapidly growing malignant tumors in recent years. According to statistics, the morbidity of cancer increases with age, accounting for 1.6% of new cancer cases and 0.6% of deaths worldwide. Melanoma has a serious impact on society and families, thus it is of great significance to find biological markers related to the diagnosis and treatment of melanoma. AIM: To explore the expression and predictive value of mir-489 and mir-21 in melanoma metastasis. METHODS: A total of 60 patients with malignant melanoma treated at our hospital from June 2017 to December 2018 were selected as a research group, while 40 healthy subjects were selected as a control group. qRT-PCR technique was used to detect miR-489 and miR-21 in serum of the two groups. ROC curve was drawn to evaluate the predictive value and diagnostic efficiency. Spearman test was used for correlation analysis. Logistic single- and multiple-factor analyses were performed to identify the risk factors related to melanoma metastasis. RESULTS: The expression of miR-489 in the research group was significantly lower than that in the control group (P < 0.001). However, the expression of miR-21 in the research group was significantly higher than that in the control group (P < 0.001). The expression of miR-489 and miR-21 was related to TNM stage and metastasis (P < 0.001). In the diagnosis of melanoma patients, the sensitivity, specificity, and AUC of miR-489 alone were 75.56%, 80.00%, and 0.852, respectively. The sensitivity, specificity, and AUC of miR-21 alone were 77.78%, 82.22%, and 0.844, respectively. MiR-489 was negatively correlated with TNM stage of melanoma (r = -0.612, P < 0.001), while miR-21 was positively correlated with TNM stage (r = 0.609, P < 0.001). Logistic single- and multiple-factor regression analyses showed that TNM stage, miR-489, and mir-21 were independent risk factors for malignant melanoma metastasis. CONCLUSION: MiR-489 and miR-21 may participate in the process of melanoma occurrence, development, and metastasis, and can be used as potential serum biomarkers for melanoma metastasis diagnosis and disease assessment.

Significance of circulating tumor cells in osteosarcoma patients treated by neoadjuvant chemotherapy and surgery.

PURPOSE: By examining and identifying circulating tumor cell (CTC) counts and subtypes of peripheral blood in osteosarcoma patients, we evaluated the relationship between CTCs and characteristics of osteosarcoma patients, as well as CTC changes after neoadjuvant chemotherapy and surgery. METHODS: CanPatrol™ CTC technology was used to detect CTCs in peripheral blood before and after treatment in 32 osteosarcoma patients. Peripheral blood samples from 10 healthy volunteers were included as controls and examined for the presence of CTCs. RESULTS: Of the 32 osteosarcoma patients, CTCs were detected in 30 patients before treatment, and the average CTC count was 14.06±9.08. No CTCs were detected in the 10 healthy volunteers. The detected CTCs were divided into epithelial CTCs, mesenchymal CTCs (M-CTCs), and biophenotypic epithelial/mesenchymal CTCs. The average number of pretreatment CTCs was higher in stage III patients than in stage IIB patients (P=0.012). Twenty-eight patients were screened for changes in CTC count at 1 week after neoadjuvant chemotherapy and at 4 weeks after surgery. We divided these 28 patients into two groups according to the changes in the percentage of M-CTCs before and after treatment, and the results showed that the disease-free survival (DFS) was significantly shorter in the M-CTC percentage-increased group than in the M-CTC percentage-decreased or no-change group (P=0.032). Five patients with stage II osteosarcoma were examined for CTCs at the appearance of lung metastases, and the total number of CTCs was found to be higher at the appearance of lung metastases than before treatment in these patients. CONCLUSION: The rate of presence of CTCs in the peripheral blood of osteosarcoma patients is high, and patients with an increased percentage of M-CTCs after treatment have a shorter DFS. The dynamic monitoring of changes in CTC counts after treatment has clinical significance for the timely detection of recurrence or metastasis.

Prognostic Value of a Long Non-coding RNA Signature in Localized Clear Cell Renal Cell Carcinoma.

BACKGROUND: Long non-coding RNAs (lncRNAs) can be used as prognostic biomarkers in many types of cancer. OBJECTIVE: We sought to establish an lncRNA signature to improve postoperative risk stratification for patients with localized clear cell renal cell carcinoma (ccRCC). DESIGN, SETTING, AND PARTICIPANTS: Based on the RNA-seq data of 444 stage I-III ccRCC tumours from The Cancer Genome Atlas project, we built a four-lncRNA-based classifier using the least absolute shrinkage and selection operation (LASSO) Cox regression model in 222 randomly selected samples (training set) and validated the classifier in the remaining 222 samples (internal validation set). We confirmed this classifier in an external validation set of 88 patients with stage I-III ccRCC from a Japan cohort and using quantitative reverse transcription polymerase chain reaction (RT-PCR) in another three independent sets that included 1869 patients from China with stage I-III ccRCC. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Univariable and multivariable Cox regression, Harrell's concordance index (c-index), and time-dependent receiver operating characteristic curves were used to evaluate the association of the classifier with overall survival, disease-specific survival, and disease-free survival. RESULTS AND LIMITATIONS: Using the LASSO Cox regression model, we built a classifier named RCClnc4 based on four lncRNAs: ENSG00000255774, ENSG00000248323, ENSG00000260911, and ENSG00000231666. In the RNA-seq and RT-PCR data sets, the RCClnc4 signature significantly stratified patients into high-risk versus low-risk groups in terms of clinical outcome across and within subpopulations and remained as an independent prognostic factor in multivariate analyses (hazard ratio range, 1.34 [95% confidence interval {CI}: 1.03-1.75; p=0.028] to 1.89 [95% CI, 1.55-2.31; p<0.001]) after adjusting for clinical and pathologic factors. The RCClnc4 signature achieved a higher accuracy (mean c-index, 0.72) than clinical staging systems such as TNM (mean c-index, 0.62) and the stage, size, grade, and necrosis (SSIGN) score (mean c-index, 0.64), currently reported prognostic signatures and biomarkers for the estimation of survival. When integrated with clinical characteristics, the composite clinical and lncRNA signature showed improved prognostic accuracy in all data sets (TNM + RCClnc4 mean c-index, 0.75; SSIGN + RCClnc4 score mean c-index, 0.75). The RCClnc4 classifier was able to identify a clinically significant number of both high-risk stage I and low-risk stage II-III patients. CONCLUSIONS: The RCClnc4 classifier is a promising and potential prognostic tool in predicting the survival of patients with stage I-III ccRCC. Combining the lncRNA classifier with clinical and pathological parameters allows for accurate risk assessment in guiding clinical management. PATIENT SUMMARY: The RCClnc4 classifier could facilitate patient management and treatment decisions.

KRT8 upregulation promotes tumor metastasis and is predictive of a poor prognosis in clear cell renal cell carcinoma.

Keratin 8 (KRT8) plays an essential role in the development and metastasis of multiple human cancers. However, its role in clear cell renal cell carcinoma (ccRCC) remains unexplored. Here, we investigated the expression pattern, clinical significance, and function of KRT8 in ccRCC. KRT8 mRNA and protein levels were determined in two large cohorts using quantitative real-time polymerase chain reaction (qRT-PCR) and tissue microarray (TMA) immunohistochemistry (IHC), respectively. We found that KRT8 expression was upregulated in ccRCC and vein tumor thrombi (VTTs). KRT8 overexpression in ccRCC was significantly correlated with aggressive characteristics and was predictive of a poor prognosis in ccRCC patients. Moreover, KRT8 overexpression in renal cancer cell lines promoted cell migration and invasion. In contrast, KRT8 knockdown suppressed ccRCC metastasis both in vitro and in vivo. In addition, our findings showed that KRT8 promoted ccRCC metastasis by increasing IL-11 expression, causing IL-11 autocrine induction, and triggering STAT3 signaling. Overall, this study established the significance of KRT8-IL-11 axis activation in aggressive ccRCC and defined a novel critical signaling mechanism that drives human ccRCC invasion and metastasis.

Effect of Cigarette Smoking on Risk of Hip Fracture in Men: A Meta-Analysis of 14 Prospective Cohort Studies.

BACKGROUND: Several observational studies have suggested an association between cigarette smoking and risk of hip fracture. However, no formal systematic review or meta-analysis was performed to summarize this risk in men. MATERIALS AND METHODS: A search was applied to MEDLINE, EMBASE, and web of science (up to November 1 2016). All prospective cohort studies assessing risk of hip fracture with the factor of cigarette smoking in men without language restriction were reviewed, and qualities of all included studies were assessed using the Newcastle-Ottawa Scale. Two authors independently assessed literatures and extracted information eligibility, and any disagreement was resolved by consensus. Newcastle-Ottawa quality assessment scale was used to evaluate studies' quality in meta-analyses. We calculated the RR with 95% CIs in a random-effects model as well as the fixed-effects model using the metan command in the STATA version 12.0 (StataCorp, USA). RESULTS: Fourteen prospective cohort studies were eligible for the present analysis. A meta-analysis of 12 prospective studies showed that the relative risk (RR) for current male smoking was 1.47 [95% confidence interval (CI) (1.28-1.66), p = 0.54; I2 = 0%]. Subgroup analyses show study characteristics (including geography region, length of follow-up, size of cohorts and study quality) did not substantially influence these positive associations. Eight studies reported the RRs for former smokers compared with never smokers and the pooled RR was 1.15 [95% CI, (0.97-1.34), (I2 = 0%, p = 0.975)]. CONCLUSIONS: The present meta-analysis of 14 prospective studies suggests that, compared with never smokers, cigarette smoking increases risk of hip fracture in man, specifically in current smokers. However, further larger prospective cohorts with more power or meta-analysis of individual patient data are needed to confirm this association.

ATF2 predicts poor prognosis and promotes malignant phenotypes in renal cell carcinoma.

BACKGROUND: Activating transcription factor 2 (ATF2) is a basic helix-loop-helix transcription factor, which has been shown to participate in the pathobiology of numerous cancers. However, the role of ATF2 in renal cell carcinoma (RCC) remains unclear. METHODS: ATF2 knockdown and overexpression studies were performed in RCC cells to evaluate changes in cell viability, cell cycle, apoptosis, migration and invasion. Xenograft models were used to examine the tumorigenic and metastatic capability of RCC cells upon ATF2 suppression. The expression of ATF2 in human RCC samples was determined using immunohistochemistry on a tissue microarray. RESULTS: ATF2 knockdown in RCC cells reduced their proliferative and metastatic potentials, whereas ATF2 overexpression enhanced these properties. Mechanistic studies revealed that the transcription of CyclinB1, CyclinD1, Snail and Vimentin was directly regulated by ATF2 in RCC cells. Moreover, ATF2 was shown to be highly expressed in RCC tissues, especially in tumors with metastases. High expression of ATF2 correlated with aggressive clinico-pathological characteristics and predicted poor prognosis of RCC patients. CONCLUSIONS: ATF2 exerts an oncogenic role in RCC and could serve as an important prognostic biomarker.

Exosome-Transmitted lncARSR Promotes Sunitinib Resistance in Renal Cancer by Acting as a Competing Endogenous RNA.

Sunitinib resistance is a major challenge for advanced renal cell carcinoma (RCC). Understanding the underlying mechanisms and developing effective strategies against sunitinib resistance are highly desired in the clinic. Here we identified an lncRNA, named lncARSR (lncRNA Activated in RCC with Sunitinib Resistance), which correlated with clinically poor sunitinib response. lncARSR promoted sunitinib resistance via competitively binding miR-34/miR-449 to facilitate AXL and c-MET expression in RCC cells. Furthermore, bioactive lncARSR could be incorporated into exosomes and transmitted to sensitive cells, thus disseminating sunitinib resistance. Treatment of sunitinib-resistant RCC with locked nucleic acids targeting lncARSR or an AXL/c-MET inhibitor restored sunitinib response. Therefore, lncARSR may serve as a predictor and a potential therapeutic target for sunitinib resistance.

Tim-3 expression represents dysfunctional tumor infiltrating T cells in renal cell carcinoma.

PURPOSE: Renal cell carcinoma (RCC) is the most common cancer of kidney. Evidences have shown that RCC is sensitive to various immunotherapies. Tim-3 plays a role in suppressing Th1-mediated immune responses. However, no study has yet examined the effect of Tim-3 on tumor infiltrating lymphocytes (TILs) in RCC. METHODS: We investigated the expression and function of Tim-3 on TIL CD4+ T cells and TIL CD8+ T cells from 30 RCC patients. RESULTS: Levels of Tim-3 were significantly increased on both TIL CD4+ T cells and TIL CD8+ T cells and were associated with higher stages of the cancer. Also, GATA-3 and interferon gamma (IFN-γ) were down-regulated, whereas T-bet was up-regulated in TIL Tim-3+ T cells, indicating that Tim-3 expression defined a population of dysfunctional TIL Th1/Tc1 cells. Mechanism analyses showed that TIL Tim-3-expressing CD8+ T cells exhibited impaired Stat5 and p38 signaling pathway. Blocking the Tim-3 pathway restored cell proliferation and increased IFN-γ production in TIL CD4+ and CD8+ T cells of RCC. CONCLUSIONS: These results suggest that Tim-3 may be used as a novel target for increasing immune responses in RCC tumor microenvironment.

Interleukin 10-expressing B cells inhibit tumor-infiltrating T cell function and correlate with T cell Tim-3 expression in renal cell carcinoma.

Renal cell carcinoma is among the leading causes of cancer-related death and was found to induce IL-10. We started by focusing on IL-10-secreting cells in tumor-infiltrating lymphocytes in renal cell carcinoma patients and observed that both CD3(+) T cells and CD19(+) B cells contributed to an elevated IL-10 expression. We then focused on IL-10-expressing B cells, and found that compared to non-IL-10-producing B cells, the IL-10-expressing B cells had significantly lower levels of CD19 and CD20 expression, a lack of IgM and IgD expression, while the level of CD27 was elevated. Moreover, culturing under unstimulated conditions resulted in higher antibody production by these IL-10-producing B cells than their peripheral blood counterparts, which strongly suggested that they are plasmablast-differentiating cells. Both IgA and IgG subtypes were found but IgA had a higher relative abundance in the tumor-infiltrating fraction. We then observed inverse correlations between the frequency of IL-10-producing B cells and pro-inflammatory cytokine-producing T cells and T cell proliferation. The expression of T cell exhaustion marker Tim-3, however, was upregulated in patients with high frequencies of IL-10-producing B cells. Moreover, supernatant from tumor B cells suppressed T cell inflammation. In addition, frequencies of IL-10-producing tumor-infiltrating B cells were inversely correlated with resected tumor size, and were higher in later stage tumors. Together, our data demonstrated that IL-10-producing B cells had plasmablast-differentiating phenotype, and could contribute to T cell immunosuppression in renal cell carcinoma.

Adiponectin is associated with increased mortality in patients with already established cardiovascular disease: a systematic review and meta-analysis.

BACKGROUND: The overall quantitative estimate on the possible association of adiponectin concentrations with mortality in patients with cardiovascular diseases (CVD) has not been reported. METHODS: We performed a systematic review and meta-analysis of prospective studies to evaluate the overall quantitative estimates on the adiponectin levels for risk of mortality in patients with CVD. MEDLINE, EMBASE, CINAHL, and the Cochrane Library (up to Mar 22, 2014) were used to search for studies evaluating the effect of adiponectin levels on mortality in patients with CVD. Random-effect models were selected to estimate overall effect estimates. RESULTS: Data from 14063 CVD patients enrolled in 15 prospective cohort and 1 nested case control studies were collated. The meta-analyses showed strong positive association of adiponectin with all-cause (n=14 studies, overall pooled effect estimate=1.45 [95% CI, 1.17-1.79]) and cardiovascular (n=11 studies, overall pooled effect estimate=1.69 [1.35-2.10]) mortality, for the highest tertile of adiponectin levels versus the lowest tertile. Subgroup analyses show study characteristics (including effect estimate, mean age, study location, sample sizes, gender, durations of follow-up, types of primary event, and acute or chronic CVD) did not substantially influence these positive associations. CONCLUSIONS: Our results showed that increased baseline plasma adiponectin levels are significantly associated with elevated risk of all-cause and cardiovascular mortality in subjects with CVD. These positive associations may have been amplified by adjustment for potential intermediates or residual confounding, and their basis requires further investigation.

Clinical significance of colonoscopy in patients with upper gastrointestinal polyps and neoplasms: a meta-analysis.

BACKGROUND: Some authors have studied the relationship between the presence of polyps, adenomas and cancers of upper gastrointestinal tract (stomach and duodenum) and risk of colorectal polyps and neoplasms; however, the results are controversial, which may be due to study sample size, populations, design, clinical features, and so on. No meta-analysis, which can be generalized to a larger population and could provide a quantitative pooled risk estimate of the relationship, of this issue existed so far. METHODS: We performed a meta-analysis to evaluate risk of colorectal polyps or neoplasms in patients with polyps, adenomas or cancers in upper gastrointestinal tract comparing with controls. A search was conducted through PubMed, EMBASE, reference lists of potentially relevant papers, and practice guidelines up to 27 November 2013 without languages restriction. Odd ratios (ORs) were pooled using random-effects models. RESULTS: The search yielded 3 prospective and 21 retrospective case-control studies (n = 37152 participants). The principal findings included: (1) OR for colorectal polyps was 1.15 (95% CI, 1.04-1.26) in the gastric polyps group comparing with control groups; (2) Patients with gastric polyps and neoplasms have higher risk (OR, 1.31 [95% CI, 1.06-1.62], and 1.72 [95% CI, 1.42-2.09], respectively) of colorectal neoplasms comparing with their controls; and (3) Positive association was found between the presence of colorectal neoplasms and sporadic duodenal neoplasms (OR, 2.59; 95% CI, 1.64-4.11). CONCLUSIONS: Findings from present meta-analysis of 24 case-control studies suggest that the prevalence of colorectal polyps was higher in patients with gastric polyps than in those without gastric polyps, and the risk of colorectal neoplasms increases significantly in patients with gastric polyps, neoplasms, and duodenal neoplasms. Therefore, screening colonoscopy should be considered for patients with upper gastrointestinal polyps and neoplasms.

Intravenous magnesium prevents atrial fibrillation after coronary artery bypass grafting: a meta-analysis of 7 double-blind, placebo-controlled, randomized clinical trials.

BACKGROUND: Postoperative atrial fibrillation (POAF) is the most common complication after coronary artery bypass grafting (CABG). The preventive effect of magnesium on POAF is not well known. This meta-analysis was undertaken to assess the efficacy of intravenous magnesium on the prevention of POAF after CABG. METHODS: Eligible studies were identified from electronic databases (Medline, Embase, and the Cochrane Library). The primary outcome measure was the incidence of POAF. The meta-analysis was performed with the fixed-effect model or random-effect model according to heterogeneity. RESULTS: Seven double-blind, placebo-controlled, randomized clinical trials met the inclusion criteria including 1,028 participants. The pooled results showed that intravenous magnesium reduced the incidence of POAF by 36% (RR 0.64; 95% confidence interval (CI) 0.50-0.83; P = 0.001; with no heterogeneity between trials (heterogeneity P = 0.8, I2 = 0%)). CONCLUSIONS: This meta-analysis indicates that intravenous magnesium significantly reduces the incidence of POAF after CABG. This finding encourages the use of intravenous magnesium as an alternative to prevent POAF after CABG. But more high quality randomized clinical trials are still need to confirm the safety.

N-Acetylcysteine supplementation for the prevention of atrial fibrillation after cardiac surgery: a meta-analysis of eight randomized controlled trials.

BACKGROUND: Atrial fibrillation is the most common type of arrhythmia after cardiac surgery. An increasing body of evidence demonstrates that oxidative stress plays a pivotal role in the pathophysiology of atrial fibrillation. N-acetylcysteine (NAC) is a free radical scavenger, and may attenuate this pathophysiologic response and reduce the incidence of postoperative AF (POAF). However, it is unclear whether NAC could effectively prevent POAF. Therefore, this meta-analysis aims to assess the efficacy of NAC supplementation on the prevention of POAF. METHODS: Medline and Embase were systematically reviewed for studies published up to November 2011, in which NAC was compared with controls for adult patients undergoing cardiac surgery. Outcome measures comprised the incidence of POAF and hospital length of stay (LOS). The meta-analysis was performed with the fixed-effect model or random-effect model according to the heterogeneity. RESULTS: Eight randomized trials incorporating 578 patients provided the best evidence and were included in this meta-analysis. NAC supplementation significantly reduced the incidence of POAF (OR 0.62, 95% CI 0.41 to 0.93; P = 0.021) compared with controls, but had no effect on LOS (WMD -0.07, 95% CI -0.42 to 0.28; P = 0.703). CONCLUSIONS: The prophylactic NAC supplementation may effectively reduce the incidence of POAF. However, the overall quality of current studies is poor and further research should focus on adequately powered randomized controlled trials with POAF incidence as a primary outcome measure.