Sequential Organ Failure Assessment Score in the ICU As a Predictor of Long-Term Survival After Cardiac Surgery

Surgical aortic valve replacement in octogenarians: Single-center perioperative outcomes and five-year survival

INTRODUCTION AND OBJECTIVES

Aortic stenosis is the most common valvular heart disease. The number of octogenarians proposed for intervention is growing due to increased lifespan. In this manuscript we aim to evaluate perioperative outcome and long-term survival after surgical aortic valve replacement (SAVR) in octogenarians, comparing patients with low surgical risk (EuroscoreII <4%) with intermediate-high risk (EuroscoreII ≥4%).

METHODS

A retrospective observational single-center cohort study with 195 patients aged ≥80 years old, who underwent SAVR between 2017 and 2021, was conducted. Patients were divided into two groups according to EuroscoreII: (1) Low risk (EuroscoreII <4%) with intermediate-high risk (EuroscoreII ≥4%). Continuous variables are presented in median (IQR), analyzed using Wilcoxon rank sum test; categorical variables in percentages, analyzed using chi-squared test; and survival was analyzed by Kaplan-Meier, open cohort, and the log-rank test was performed.

RESULTS

The overall median age was 82 (IQR 81-83), with 4.6% of the patients ≥85 years old. 23.6% of the patients presented EuroscoreII ≥4%. No complications were observed in 26.2%, with a significantly higher rate in intermediate-high risk patients. Postoperative need for hemodynamic support was the most frequent complication, followed by postoperative acute kidney injury and the use of blood products. Overall median ICU stay was three days (2-4) and hospital length of stay (LOS) six days (5-8). Patients with intermediate-high risk and those with complications had longer ICU LOS. At 12 months, overall survival was 96.4%, at three years 94.1% and 5 years 75.4%. Patients with low surgical risk had higher survival proportions up to 5 years.

CONCLUSION

SAVR in patients ≥80 years is associated with low in-hospital mortality, although a significant proportion of patients develop complications. Long-term follow-up up to five years after surgery is acceptable in octogenarians with low surgical risk.

The impact of cardiopulmonary bypass time on the Sequential Organ Failure Assessment score after cardiac surgery

OBJECTIVES

Postoperative organ dysfunction is common after cardiac surgery, particularly when cardiopulmonary bypass (CPB) is used. The Sequential Organ Failure Assessment (SOFA) score is validated to predict morbidity and mortality in cardiac surgery. However, the impact of CPB duration on postoperative SOFA remains unclear.

METHODS

This is a retrospective study. Categorical values are presented as percentages. The comparison of SOFA groups utilized the Kruskal-Wallis chi-squared test, complemented by ad hoc Dunn's test with Bonferroni correction. Multinomial logistics regressions were employed to evaluate the relationship between CPB time and SOFA.

RESULTS

A total of 1032 patients were included. CPB time was independently associated with higher postoperative SOFA scores at 24 h. CPB time was significantly higher in patients with SOFA 4-5 (**P = 0.0022) or higher (***P < 0.001) when compared to SOFA 0-1. The percentage of patients with no/mild dysfunction decreased with longer periods of CPB, down to 0% for CPB time >180min (50% of the patients with >180m in of CPB presented SOFA ≥ 10). The same trend is observed for each of the SOFA variables, with higher impact in the cardiovascular and renal systems. Severe dysfunction occurs especially >200 min of CPB (cardiovascular system >100 min; other systems mainly >200 min).

CONCLUSIONS

CPB time may predict the probability of postoperative SOFA categories. Patients with extended CPB durations exhibited higher SOFA scores (overall and for each variable) at 24 h, with higher proportion of moderate and severe dysfunction with increasing times of CPB.

Assessment of Racial and Ethnic Differences in Oxygen Supplementation Among Patients in the Intensive Care Unit

IMPORTANCE

Pulse oximetry (SpO2) is routinely used for transcutaneous monitoring of blood oxygenation, but it can overestimate actual oxygenation. This is more common in patients of racial and ethnic minority groups. The extent to which these discrepancies are associated with variations in treatment is not known.

OBJECTIVE

To determine if there are racial and ethnic disparities in supplemental oxygen administration associated with inconsistent pulse oximeter performance.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study was based on the Medical Information Mart for Intensive Care (MIMIC)-IV critical care data set. Included patients were documented with a race and ethnicity as Asian, Black, Hispanic, or White and were admitted to the intensive care unit (ICU) for at least 12 hours before needing advanced respiratory support, if any. Oxygenation levels and nasal cannula flow rates for up to 5 days from ICU admission or until the time of intubation, noninvasive positive pressure ventilation, high-flow nasal cannula, or tracheostomy were analyzed.

MAIN OUTCOMES AND MEASURES

The primary outcome was time-weighted average supplemental oxygen rate. Covariates included race and ethnicity, sex, SpO2-hemoglobin oxygen saturation discrepancy, data duration, number and timing of blood gas tests on ICU days 1 to 3, partial pressure of carbon dioxide, hemoglobin level, average respiratory rate, Elixhauser comorbidity scores, and need for vasopressors or inotropes.

RESULTS

This cohort included 3069 patients (mean [SD] age, 66.9 [13.5] years; 83 were Asian, 207 were Black, 112 were Hispanic, 2667 were White). In a multivariable linear regression, Asian (coefficient, 0.602; 95% CI, 0.263 to 0.941; P = .001), Black (coefficient, 0.919; 95% CI, 0.698 to 1.140; P < .001), and Hispanic (coefficient, 0.622; 95% CI, 0.329 to 0.915; P < .001) race and ethnicity were all associated with a higher SpO2 for a given hemoglobin oxygen saturation. Asian (coefficient, -0.291; 95% CI, -0.546 to -0.035; P = .03), Black (coefficient, -0.294; 95% CI, -0.460 to -0.128; P = .001), and Hispanic (coefficient, -0.242; 95% CI, -0.463 to -0.020; P = .03) race and ethnicity were associated with lower average oxygen delivery rates. When controlling for the discrepancy between average SpO2 and average hemoglobin oxygen saturation, race and ethnicity were not associated with oxygen delivery rate. This discrepancy mediated the effect of race and ethnicity (-0.157; 95% CI, -0.250 to -0.057; P = .002).

CONCLUSIONS AND RELEVANCE

In this cohort study, Asian, Black, and Hispanic patients received less supplemental oxygen than White patients, and this was associated with differences in pulse oximeter performance, which may contribute to known race and ethnicity-based disparities in care.