Risk factors for in-hospital mortality after coronary artery bypass grafting in patients 80 years old or older: a retrospective case-series study

The impact of age on outcomes of coronary artery bypass grafting

OBJECTIVE

As the population ages, increasing number of older patients are undergoing adult cardiac surgery. The purpose of the study is to assess the impact of age on postoperative outcomes in patients that undergo coronary artery bypass grafting (CABG).

METHODS

Patients that are ≥70 years old who underwent CABG were selected from the Nationwide/National Inpatient Sample from 2010 to 2015 using ICD-9-CM diagnosis and procedure codes. The patients who were 70-79 years old were compared to patients aged 80-89 years old to determine if the age difference of the patients had an impact on surgical outcomes. In addition, a secondary endpoint is to compare surgical outcomes between the 2 genders of the patients 80-89 years old. The rates of postoperative complications, and mortality were compared.

RESULTS

A total of 67,568 patients were identified who were ≥ 70 years old and underwent CABG. Compared to the Septuagenarians, the Octogenarians were more likely to develop cardiac complications (OR [odds ratio] =1.20, 95% CI [confidence interval] 1.12-1.23. They were also more likely to develop renal complications (P < 0001), and respiratory complications (P < 0001). The Octogenarians were also more likely to bleed postoperatively (P < 0.0001) and have a higher mortality (P < 0001). Furthermore, the female Octogenarians had a higher mortality (OR 1.25 95% CI 1.07-1.46) compared to males in the same age group.

CONCLUSIONS

The patients who were ≥ 80-89 years old had worse postoperative outcomes. The Octogenarians who were females had a higher mortality compared to their male counterparts.

Postoperative interleukin-8 levels are related to the duration of coronary artery bypass grafting surgery and predict in-hospital postsurgical complications

Introduction: The magnitude of the very early coronary artery bypass grafting (CABG)-related inflammatory response has been shown to influence post-CABG outcomes. However, the dynamics of the systemic inflammatory response to CABG beyond the very early postoperative phase and its relevance to clinical outcomes are not fully understood.

Methods: Circulating levels of several inflammatory markers were determined in 30 consecutive patients undergoing elective isolated on-pump CABG one day prior (D0-1), and 2 (D2) and 5 days post-CABG.

Results: CABG was associated with a significant increase in all studied inflammatory marker levels (all p<0.05 for D2 versus D0-1). D2 post-CABG IL-6 and IL-8 levels were both significantly positively correlated with extracorporeal circulation (ECC) and aortic clamping (AC) times (all p<0.05), whereas a weaker correlation was observed between D2 post-CABG IL-8 levels and total surgery time (r=0.42, p=0.02). In multiple regression analysis, D2 IL-8 levels independently predicted post-CABG kidney (p= 0.02) and liver (p = 0.04) dysfunction, as well as a sum of post-CABG major complications ≥2 (p = 0.04).

Conclusions: In this prospective study, longer duration of cardiopulmonary bypass caused a larger post-CABG inflammatory surge, whereas the duration of total CABG surgery had a less significant effect. IL-8 hyperresponders had greater risk of developing kidney and liver dysfunction and presented more major post-CABG complications. These data suggest that targeting the IL-8 pathway using antiinflammatory agents, or simply by shortening the duration of cardiopulmonary bypass could improve the in-hospital post-CABG outcomes in this population.