Impact of Chronic Kidney Disease on Clinical Outcomes during Hospitalization and Five-Year Follow-Up after Coronary Artery Bypass Grafting.

Background: Chronic kidney disease (CKD) is often associated with multiple comorbidities including diabetes mellitus, and each has its own complications and impact after cardiac surgery including coronary revascularization. The objective of this work was to study the impact of CKD on clinical outcomes after coronary artery bypass grafting (CABG) and to compare outcomes in patients with different grades of renal functions. We retrospectively reviewed all patients who underwent CABG from January 2016 to August 2020 at our tertiary care hospital using electronic medical records. Results: The study included 410 patients with a median age of 60 years, and 28.6% of them had CKD and hospital mortality of 2.7%. About 71.4% of the patients had GFR > 60 mL/min per 1.73 m2, 18.1% had early CKD (GFR 30-60), 2.7% had late CKD (GFR < 30), and 7.8% of them had end-stage renal disease (ESRD) requiring dialysis. The CKD group had significantly more frequent hospital mortality (p = 0.04), acute cerebrovascular stroke (p = 0.03), acute kidney injury (AKI) (p < 0.001), longer ICU stay (p = 0.002), post-ICU stay (p = 0.001), and sternotomy wound debridement (p = 0.03) compared to the non-CKD group. The frequencies of new need for dialysis were 2.4% vs. 14.9% vs. 45.5% (p < 0.001) in the patients with GFR > 60 mL/min per 1.73 m2, early CKD, and late CKD, respectively. Acute cerebral stroke (OR: 10.29, 95% CI: 1.82-58.08, and p = 0.008), new need for dialysis (OR: 25.617, 95% CI: 13.78-85.47, and p < 0.001), and emergency surgery (OR: 3.1, 95% CI: 1.82-12.37, and p = 0.036) were the independent predictors of hospital mortality after CABG. The patients with CKD had an increased risk of strokes (HR: 2.14, 95% CI: 1.20-3.81, and p = 0.01) but insignificant mortality increase (HR: 1.44, 95% CI: 0.42-4.92, and p = 0.56) during follow-up. Conclusion: The patients with CKD, especially the late grade, had worse postoperative early and late outcomes compared to non-CKD patients after CABG. Patients with dialysis-independent CKD had increased risks of needing dialysis, hospital mortality, and permanent dialysis after CABG.

Predictors and clinical outcomes of post-coronary artery bypass grafting cerebrovascular strokes.

BACKGROUND: Despite the improved medical and surgical managements, still there is a significant risk of developing acute cerebrovascular strokes after coronary artery bypass grafting (CABG). Our objectives were to study the immediate and long-term outcomes after CABG and to identify the possible predictors of post-CABG strokes. RESULTS: Between January 2016 and August 2020, 410 adult patients, mostly males (82.2%), were retrospectively enrolled after CABG. Acute postoperative strokes occurred in 31 (7.5%) patients; of them, 30 (96.8%) patients had ischemic stroke, while 1 (3.2%) had hemorrhagic stroke. Mechanical thrombectomy was done in two cases. The patients who developed acute cerebral stroke had significantly higher admission (p = 0.02) and follow-up (p < 0.001) SOFA scores, higher arterial blood lactate level (p < 0.001), longer hospitalization (p < 0.001) and more hospital mortality (p < 0.001) compared with the patients who did not develop stroke. Kaplan-Meier curves for 5-year mortality showed increased risk in those patients with postoperative stroke (HR: 23.03; 95% CI: 6.10-86.92, p < 0.001). After multivariate regression, the predictors of early postoperative stroke were carotid artery stenosis (CAS), postoperative atrial fibrillation, cardiopulmonary bypass time, prior cerebral stroke, admission SOFA score and chronic kidney disease (CKD). The predictors of late cerebrovascular stroke were CAS, combined CABG and valve surgery, CKD, atrial fibrillation, prior stroke and HbA1c. CONCLUSIONS: The development of post-CABG acute cerebrovascular stroke is associated with longer hospitalization, multiple morbidities and increased mortality. Careful assessment and management of risk factors especially atrial fibrillation and carotid artery stenosis should be implemented to decrease this substantial complication after CABG.

Performance Assessment of a Multifaceted Unfractionated Heparin Dosing Protocol in Adult Patients on Extracorporeal Membrane Oxygenator.

BACKGROUND: The use of extracorporeal membrane oxygenator (ECMO) support devices are associated with complications, including bleeding and thrombosis. Unfractionated heparin (UFH) is the gold standard anticoagulant in ECMO patients. Clinically, UFH is monitored through activated clotting time (ACT), activated partial thromboplastin time (aPTT), and anti-factor Xa assay. It is unknown which assay best predicts anticoagulation effects in adults. OBJECTIVE: To assess the correlation of UFH dosing and monitoring using an established protocol. METHODS: A pilot, prospective cohort, historically controlled study was conducted at a tertiary care hospital. Patients ≥18 years-old who received ECMO on the multifaceted anticoagulation protocol were included and compared with those on the conventional method of anticoagulation. The primary end point was to assess the correlation between UFH dose and different monitoring methods throughout 72 hours using the new protocol guided by ACT and anti-factor Xa assay. RESULTS: In each arm, 20 patients were enrolled. The study revealed that anti-factor Xa assay had the largest number of "strong" correlations 11/20 (55%), followed by both aPTT and aPTT ratio 10/20 (50%), and, finally, ACT 2/20 (10%). Concordance between anti-factor Xa assay and the other monitoring parameters in the prospective arm was generally low: 31% with aPTT ratio, 26% with ACT, and 23% with aPTT. CONCLUSION AND RELEVANCE: The adaption of a multifaceted anticoagulation protocol using anti-factor Xa assay may provide a better prediction of heparin dosing in adults ECMO patients compared with the conventional ACT-based protocol. Further studies are needed to assess the safety and different monitoring modalities.

The clinical significance of blood lactate levels in evaluation of adult patients with veno-arterial extracorporeal membrane oxygenation.

BACKGROUND: Veno-arterial ECMO is a life-supporting procedure that can be done to the patients with cardiogenic shock which is associated with hyperlactatemia. The objective of this study was to detect the validity of serial measurements of arterial lactate level in differentiating hospital mortality and neurological outcome after VA-ECMO support for adult patients with cardiogenic shock. All consecutive patients ≥ 18 years admitted with cardiogenic shock and supported with VA-ECMO between 2015 and 2019 in our tertiary care hospital were retrospectively studied. RESULTS: The study included 106 patients with a mean age of 40.2 ± 14.4 years, a mean BMI of 26.5 ± 7 and mostly males (69.8%). The in-hospital mortality occurred in 56.6% and acute cerebral strokes occurred in 25.5% of the enrolled patients. The non-survivors and the patients with acute cerebral strokes had significantly higher arterial lactate levels at pre-ECMO initiation, post-ECMO peak and after 24 h of ECMO support compared to the survivors and those without strokes, respectively. The peak arterial lactate ≥ 14.65 mmol/L measured after ECMO support had 81.7% sensitivity and 89.1% specificity for predicting hospital mortality [AUROC 0.889, p < 0.001], while the arterial lactate level ≥ 3.25 mmol/L after 24 h of ECMO support had 88.3% sensitivity and 97.8% specificity for predicting hospital mortality [AUROC 0.93, p < 0.001]. The peak lactate ≥ 15.15 mmol/L measured after ECMO support had 70.8% sensitivity and 69% specificity for predicting cerebral strokes [AUROC 0.717, p < 0.001], while the lactate level ≥ 3.25 mmol/L after 24 h of ECMO support had 79.2% sensitivity and 72.4% specificity for predicting cerebral strokes [AUROC 0.779, p < 0.001]. Progressive hyperlactatemia (OR = 1.427, 95% CI 1.048-1.944, p = 0.024) and increasing SOFA score after 48 h (OR = 1.819, 95% CI 1.374-2.409, p < 0.001) were significantly associated with in-hospital mortality after VA-ECMO support. Post hoc analysis detected a significantly high frequency of hypoalbuminemia in the non-survivors and in the patients who developed acute cerebral strokes during VA-ECMO support. CONCLUSION: Progressive hyperlactatemia after VA-ECMO initiation for adult patients with cardiogenic shock is a sensitive and specific predictor of hospital mortality and acute cerebrovascular strokes. According to our results, we could recommend early VA-ECMO initiation to achieve adequate circulatory support and better outcome.

The Validity of SOFA Score to Predict Mortality in Adult Patients with Cardiogenic Shock on Venoarterial Extracorporeal Membrane Oxygenation.

BACKGROUND: Venoarterial ECMO is increasingly used in resuscitation of adult patients with cardiogenic shock with variable mortality reports worldwide. Our objectives were to study the variables associated with hospital mortality in adult patients supported with VA-ECMO and to determine the validity of repeated assessments of those patients by the Sequential Organ Failure Assessment (SOFA) score for prediction of hospital mortality. We retrospectively studied adult patients admitted to the cardiac surgical critical care unit with cardiogenic shock supported with VA-ECMO from January 2015 to August 2019 in our tertiary care hospital. RESULTS: One hundred and six patients supported with VA-ECMO were included in our study with in-hospital mortality of 56.6%. The mean age of studied patients was 40.2 ± 14.4 years, and the patients were mostly males (69.8%) with a mean BMI of 26.5 ± 7 without statistically significant differences between survivors and nonsurvivors. Presence of CKD, chronic atrial fibrillation, and cardiac surgeries was significantly more frequent in the nonsurvivors group. The nonsurvivors had more frequent AKI (p < 0.001), more haemodialysis use (p < 0.001), more gastrointestinal bleeding (p = 0.039), more ICH (p = 0.006), and fewer ICU days (p = 0.002) compared to the survivors group. The mean peak blood lactate level was 11 ± 3 vs 16.7 ± 3.3, p < 0.001, and the mean lactate level after 24 hours of ECMO initiation was 2.2 ± 0.9 vs 7.9 ± 5.7, p < 0.001, in the survivors and nonsurvivors, respectively. Initial SOFA score ≥13 measured upon ICU admission had a 85% sensitivity and 73.9% specificity for predicting hospital mortality [AUROC = 0.862, 95% CI: 0.791-0.932; p < 0.001] with 81% PPV, 79.1% NPV, and 80.2% accuracy while SOFA score ≥13 at day 3 had 100% sensitivity and 91.3% specificity for predicting mortality with 93.8% PPV, 100% NPV, and 96.2% accuracy [AUROC = 0.995, 95% CI: 0.986-1; p < 0.001]. The ∆1 SOFA (3-1) ≥2 had 95% sensitivity and 93.5% specificity for predicting hospital mortality [AUROC = 0.958, 95% CI: 0.913-1; p < 0.001] with 95% PPV, 93.5% NPV, and 94.3% accuracy. SOFA score ≥15 at day 5 had 98% sensitivity and 100% specificity for predicting mortality with 99% accuracy [AUROC = 0.994, 95% CI: 0.982-1; p < 0.001]. The ∆2 SOFA (5-1) ≥2 had 90% sensitivity and 97.8% specificity for predicting hospital mortality [AUROC = 0.958, 95% CI: 0.909-1; p < 0.001] with 97.8% PPV, 90% NPV, and 94.8% accuracy. Multivariable regression analysis revealed that increasing ∆1 SOFA score (OR = 2.506, 95% CI: 1.681-3.735, p < 0.001) and increasing blood lactate level (OR = 1.388, 95% CI: 1.015-1.898, p = 0.04) were significantly associated with hospital mortality after VA-ECMO support for adults with cardiogenic shock. CONCLUSION: The use of VA-ECMO in adult patients with cardiogenic shock is still associated with high mortality. Serial evaluation of those patients with SOFA score during the first few days of ECMO support is a good predictor of hospital mortality. Increase in SOFA score after 48 hours and hyperlactataemia are significantly associated with increased hospital mortality.

Extracorporeal membrane oxygenation in adults: experience from the Middle East.

BACKGROUND: The literature reports conflicting results for survival after extracorporeal membrane oxygenator support, and survival differs in pediatric and adult patients. We present our institutional experience of adult extracorporeal membrane oxygenator support. METHODS: From January 2007 to December 2009, 19 adult patients required extracorporeal membrane oxygenator support after cardiac surgery or catheter interventions. It was provided on an emergency basis to 11 patients, urgently to 5, and electively to 3. Indications included post-cardiotomy cardiogenic shock, post-cardiotomy acute respiratory failure, emergency cardiac resuscitation, and post-percutaneous coronary intervention cardiogenic shock. The mean duration of support was 4 days (range, 1-11 days). RESULTS: Seven (36.84%) patients could be weaned off extracorporeal membrane oxygenator support; one (14.28%) of them survived to hospital discharge and the other 6 (85.71%) died in hospital. Twelve (63.15%) patients could not be weaned off and died while still on extracorporeal membrane oxygenator support. Overall 30-day hospital mortality was 94.73%, and survival to discharge was 5.26%. CONCLUSION: Our institutional experience of extracorporeal membrane oxygenator support for cardiac indications in adult patients indicates poor survival. It significantly increased costs by delaying imminent death and prolonging stay in the intensive care unit.