BackgroundIntraoperative transfusion is associated with adverse clinical outcomes in cardiac surgery. However, few studies have shown the impact of intraoperative red blood cell (RBC) transfusion on non-anemic patients undergoing cardiac surgery. We assessed the in-hospital clinical outcomes of non-anemic patients undergoing isolated valve replacements and investigated the predictors associated with intraoperative RBC transfusion.MethodsWe enrolled 345 non-anemic patients undergoing isolated valve replacements in our department from January 2015 to December 2019. The patients were stratified by the receipt of intraoperative RBC transfusion. Baseline characteristics were compared between groups and multiple logistic regression was used to identify the predictors for intraoperative RBC transfusion. The association between intraoperative RBC transfusion and in-hospital outcomes was also evaluated.ResultsIntraoperative RBC transfusion developed in 84 of the 345 enrolled patients (24.3%). Three independent predictors for intraoperative RBC transfusion of non-anemic patients undergoing isolated valve replacements were identified by multivariate logistic analysis, including female, iron deficiency and hemoglobin level. When the two groups were compared, a significant tendency of higher in-hospital mortality (6.0% vs. 1.1%, P = 0.033) and higher incidence of postoperative hypoxemia (9.5% vs. 2.7%, P = 0.007) were observed in the intraoperative RBC transfusion group. After adjustment, the presence of intraoperative RBC transfusion was associated with an increase in postoperative hypoxemia (OR = 3.36, 95% CI: 1.16–9.71, P = 0.026).ConclusionIntraoperative RBC transfusion was associated with poorer clinical outcomes in non-anemic adults undergoing isolated valve replacements, which significantly increased the risk of postoperative hypoxemia. The independent predictors of intraoperative RBC transfusion, such as iron deficiency and female, were identified, which may be helpful for risk assessment and perioperative management.

To explore the role of autophagic flux in the increased susceptibility of the experimental diabetic heart to ischaemia‐reperfusion (I/R) injury, we established STZ‐induced diabetic mice and performed I/R. In vitro, neonatal mouse cardiomyocytes were subjected to high glucose and hypoxia/reoxygenation challenge to mimic diabetic I/R injury. We found that experimental diabetes aggravated I/R‐induced injury than compared with nondiabetic mice. Autophagic flux was impaired in I/R hearts, and the impairment was exacerbated in diabetic mice subjected to I/R with defective autophagosome formation and clearance. Calpains, calcium‐dependent thiol proteases, were upregulated and highly activated after I/R of diabetes, while calpain inhibition attenuated cardiac function and cell death and partially restored autophagic flux. The expression levels of Atg5 and LAMP2, two crucial autophagy‐related proteins, were significantly degraded in diabetic I/R hearts, alterations that were associated with calpain activation and could be reversed by calpain inhibition. Co‐overexpression of Atg5 and LAMP2 reduced myocardial injury and normalized autophagic flux. In conclusion, experimental diabetes exacerbates autophagic flux impairment of cardiomyocytes under I/R stress, resulting in worse I/R‐induced injury. Calpain activation and cleavage of Atg5 and LAMP2 at least partially account for the deterioration of autophagic flux impairment.

Background: Nosocomial infection (NI) prolongs hospital stay and heightens mortality among patients who underwent cardiac surgery. We constructed a retrospective study to explore the prevalence of Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (SA/MRSA) nasal colonization, as well as the effects of SA/MRSA decolonization bundle measures on SA/MRSA-related infection among Chinese cardiac patients. Methods: After reviewing the medical records, we divided cardiovascular surgery patients treated at our central campus into two groups: the baseline group (treated between January 2012 and December 2013) and the intervention group (treated between May 2014 and December 2020). Intervention measures consisted of preoperative nasal screening and targeted decolonization bundle therapy. The medical records of patients at our southern campus (treated between January 2017 and December 2020) were collected as an additional control group, since we did not implement SA intervention measures at this location. The incidences of SA/ MRSA-related NI were then compared between the groups.Results: There were 794 patients in the baseline group and 2,826 in the intervention group. A total of 131 (4.6%) patients had SA nasal colonization, and among them, 33 patients (1.2%) were MRSA colonized. SA/MRSA was cleared in approximately 95% of the carriers. The total level of SA-related infection was significantly lower in the intervention group compared to the baseline group [0.354% vs. 1.133%, respectively; P=0.021; risk ratio (RR): 0.312; 95% confidence interval (CI): 0.127-0.766]. The incidence of MRSA-related infection followed the same trend (0.212% vs. 0.756%, respectively; P=0.030; RR: 0.281; 95% CI: 0.091-0.860). When compared to the southern campus, SA intervention measures at the central campus resulted in a significant reduction in total SA-related infection (1.132% vs. 0.284%, respectively; P=0.035; RR: 0.251; 95% CI: 0.077-0.820). Conclusions:The prevalence of SA/MRSA colonization is relatively low among Chinese patients who received cardiovascular surgery. Targeted decolonization bundle therapy was associated with cleared colonization and reduced incidence of SA/MRSA-related infection.