Renal Disease Is Associated With Poor Outcomes Following Isolated Coronary Artery Bypass Grafting

Central Oxygen Venous Saturation and Mortality in Patients Undergoing Coronary Artery Bypass Grafting

Purpose

Central venous oxygen saturation (ScvO₂) has been reported as a prognostic marker of in-hospital mortality when it is below 60% in certain situations. Nevertheless, it has not been widely reported in patients undergoing coronary artery bypass graft (CABG). The study determined the association between ScvO₂ and in-hospital mortality in patients undergoing CABG in a high-complexity health institution in Santiago de Cali, Colombia.

Patients and Methods

A retrospective cohort study was conducted with patients undergoing isolated CABG. The subject sample included 515 subjects aged 18 years or older. Exposure was defined as ScvO₂ <60% upon admission to the intensive care unit (ICU) following surgery. The major outcome was mortality rates after 30 days. Furthermore, exposure variables were measured at preoperative, intra-operative, and postoperative time points.

Results

A total of 103 exposed and 412 unexposed subjects were included. The final model revealed a higher mortality risk in individuals with ScvO₂ <60% upon ICU admission compared with those with higher saturation levels (relative risk 4.2, 95% confidence interval: 2.4-7.2; p = 0.001). Values were adjusted using variables such as age (>75 years), low socioeconomic stratum, chronic kidney failure before surgery, unstable angina before surgery, ischemia time (>60 min), and intra-operative inotrope use. The primary cause of death was cardiogenic shock (54.7%), followed by sepsis (25.0%) and postoperative bleeding (17.2%).

Conclusion

The study identified an association between ScvO₂ <60% and in-hospital mortality in patients undergoing CABG.

Future insights of pharmacological prevention for AKI post cardiopulmonary bypass surgery (based on PK/PD approach)

The incidence of acute kidney injury (AKI) post-cardiopulmonary bypass (CPB) can cause an increase in the rate of renal replacement therapy (RRT) and mortality rate. Compared to brain and liver damage post-CPB, AKI has the highest incidence of 83%. Based on this phenomenon, various efforts have been made to reduce the incidence of AKI post-CPB, both pharmacologically and non-pharmacologically interventions. The purpose of this review is to emphasize several renal protector agents which under optimal conditions can provide significant benefits in reducing the incidence of AKI post-CPB. This article was obtained by conducting a study on several kinds of literature, including the original article, RCT study, systematic review and meta-analysis, and other review articles. There are five renal protector agents that are the focus of this article, those are fenoldopam which effectively works to prevent the incidence of AKI post-CPB, while furosemide has shown satisfactory results in patients with decreased renal function when administered in the Renal Guard (RG) system, mannitol, and nitric oxide, both of these can also effectively reduce the incidence of AKI post‐CPB by controlling its blood concentration and timing of administration, and another form of N-Acetylcysteine, namely N‐Acetylcysteine amide has better activity as a renoprotective agent than N‐Acetylcysteine itself. The benefits of these agents can be obtained by developing devices that can control drug levels in the blood and create optimal conditions for drugs during the use of a CPB machine.