Acute Kidney Injury and Renal Replacement Therapy: A Review and Update for the Perioperative Physician.

Post-operative acute kidney injury is a devastating complication with significant morbidity and mortality associated with it. The perioperative anesthesiologist is in a unique position to potentially mitigate the risk of postoperative AKI, however, understanding the pathophysiology, risk factors and preventative strategies is paramount. There are also certain clinical scenarios, where renal replacement therapy may be indicated intraoperatively including severe electrolyte abnormalities, metabolic acidosis and massive volume overload. A multidisciplinary approach including the nephrologist, critical care physician, surgeon and anesthesiologist is necessary to determine the optimal management of these critically ill patients.

Loss of Independent Living in Patients Undergoing Transcatheter or Surgical Aortic Valve Replacement: A Retrospective Cohort Study.

BACKGROUND: The recommendation for transcatheter aortic valve replacement (TAVR) or surgical aortic valve replacement (SAVR) in patients 65 to 80 years of age is equivocal, leaving patients with a difficult decision. We evaluated whether TAVR compared to SAVR is associated with reduced odds for loss of independent living in patients ≤65, 66 to 79, and ≥80 years of age. Further, we explored mechanisms of the association of TAVR and adverse discharge. METHODS: Adult patients undergoing TAVR or SAVR within a large academic medical system who lived independently before the procedure were included. A multivariable logistic regression model, adjusting for a priori defined confounders including patient demographics, preoperative comorbidities, and a risk score for adverse discharge after cardiac surgery, was used to assess the primary association. We tested the interaction of patient age with the association between aortic valve replacement (AVR) procedure and loss of independent living. We further assessed whether the primary association was mediated (ie, percentage of the association that can be attributed to the mediator) by the procedural duration as prespecified mediator. RESULTS: A total of 1751 patients (age median [quartiles; min-max], 76 [67, 84; 23-100]; sex, 56% female) were included. A total of 27% (222/812) of these patients undergoing SAVR and 20% (188/939) undergoing TAVR lost the ability to live independently. In our cohort, TAVR was associated with reduced odds for loss of independent living compared to SAVR (adjusted odds ratio [OR adj ] 0.19 [95% confidence interval {CI}, 0.14-0.26]; P < .001). This association was attenuated in patients ≤65 years of age (OR adj 0.63 [0.26-1.56]; P = .32) and between 66 and 79 years of age (OR adj 0.23 [0.15-0.35]; P < .001), and magnified in patients ≥80 years of age (OR adj 0.16 [0.10-0.25]; P < .001; P -for-interaction = .004). Among those >65 years of age, a shorter procedural duration mediated 50% (95% CI, 28-76; P < .001) of the beneficial association of TAVR and independent living. CONCLUSIONS: Patients >65 years of age undergoing TAVR compared to SAVR had reduced odds for loss of independent living. This association was partly mediated by shorter procedural duration. No association between AVR approach and the primary end point was found in patients ≤65 years of age.

Mechanical Circulatory Support: Primer for Consultant Specialists.

Mechanical life support therapies exist in many forms to temporarily replace the function of vital organs. Generally speaking, these tools are supportive therapy to allow for organ recovery but, at times, require transition to long-term mechanical support. This review will examine nonrenal extracorporeal life support for cardiac and pulmonary support as well as other mechanical circulatory support options. This is intended as a general primer and overview to assist nephrologist consultants participating in the care of these critically ill patients who often experience acute renal injury as a result of cardiopulmonary shock and from their exposure to mechanical circulatory support.

Social determinants of health affect unplanned readmissions following acute myocardial infarction.

Background: Low socioeconomic status predicts inferior clinical outcomes in many patient populations. The effects of patient insurance status and hospital safety-net status on readmission rates following acute myocardial infarction are unclear. Materials & methods: A retrospective review of State Inpatient Databases for New York, California, Florida and Maryland, 2007-2014. Results: A total of 1,055,162 patients were included. Medicaid status was associated with 37.7 and 44.0% increases in risk-adjusted readmission odds at 30 and 90 days (p < 0.0001). Uninsured status was associated with reduced odds of readmission at both time points. High-burden safety-net status was associated with 9.6 and 9.5% increased odds of readmission at 30 and 90 days (p < 0.0003). Conclusion: Insurance status and hospital safety-net burden affect readmission odds following acute myocardial infarction.

To Swan or Not to Swan: Indications, Alternatives, and Future Directions.

The pulmonary artery catheter (PAC) has revolutionized bedside assessment of preload, afterload, and contractility using measured pulmonary capillary wedge pressure, calculated systemic vascular resistance, and estimated cardiac output. It is placed percutaneously by a flow-directed balloon-tipped technique through the venous system and the right heart to the pulmonary artery. Interest in the hemodynamic variables obtained from PACs paved the way for the development of numerous less-invasive hemodynamic monitors over the past 3 decades. These devices estimate cardiac output using concepts such as pulse contour and pressure analysis, transpulmonary thermodilution, carbon dioxide rebreathing, impedance plethysmography, Doppler ultrasonography, and echocardiography. Herein, the authors review the conception, technologic advancements, and modern use of PACs, as well as the criticisms regarding the clinical utility, reliability, and safety of PACs. The authors comment on the current understanding of the benefits and limitations of alternative hemodynamic monitors, which is important for providers caring for critically ill patients. The authors also briefly discuss the use of hemodynamic monitoring in goal-directed fluid therapy algorithms in Enhanced Recovery After Surgery programs.

Preoperative Opioid Use Disorder Is Associated With Poorer Outcomes After Coronary Bypass and Valve Surgery: A Multistate Analysis, 2007-2014.

OBJECTIVE: To determine the effect of preoperative opioid use disorder (OUD) on postoperative outcomes in patients undergoing coronary artery bypass grafting (CABG) and heart valve surgery. DESIGN: Retrospective, observational study using data from the State Inpatient Database and the Healthcare Cost and Utilization Project. SETTING: Inpatient data from Florida, California, New York, Maryland, and Kentucky between 2007 and 2014. PARTICIPANTS: A total of 377,771 CABG patients and 194,469 valve surgery patients age ≥18 years. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The prevalence of OUD was 2,136 (0.57%) in the CABG group and 2,020 (1.04%) in the valve surgery group. There was no significant difference in mortality between the OUD and non-OUD groups in both surgical cohorts (both p > 0.05). On adjusted analyses, preoperative OUD was significantly associated with increased adjusted odds ratios (aORs) of 30-day hospital readmission (CABG aOR 1.47 [95% confidence interval {CI} 1.30-1.66]; valve surgery aOR 1.41 [95% CI 1.27-1.56]) and 90-day hospital readmission (CABG aOR 1.47 [95% CI 1.31-1.64]; valve surgery aOR 1.33 [95% CI 1.23-1.43]). Preoperative OUD was significantly associated with increased adjusted risk ratios (aRRs) of hospital length of stay (CABG aRR 1.13 [95% CI 1.10-1.16]; valve surgery aRR 1.63 [95% CI 1.54-1.72]) and total hospitalization charges (CABG aRR 1.05 [95% CI 1.03-1.07]; valve surgery aRR 1.28 [95% CI 1.24-1.32]). CONCLUSION: Preoperative OUD is significantly associated with poorer outcomes after cardiac surgery, including increased 30- and 90-day readmissions, hospital length of stay, and total hospitalization charges. Opioid use should be considered a modifiable risk factor in cardiac surgery, and interventions should be attempted preoperatively.

The impact of hospital safety-net burden on mortality and readmission after CABG surgery.

BACKGROUND AND AIM: Safety-net hospitals (SNHs) serve high proportions of uninsured and Medicaid patients. Data conflict as to the impact of hospital safety-net status on perioperative complications. Our goal was to assess the effect of hospital safety-net burden on mortality and readmission following coronary artery bypass graft (CABG) surgery. METHODS: A retrospective analysis was performed using five State Inpatient Databases (2007-2014) for isolated CABG surgery. High, medium, and low burden hospitals were those with the highest, middle, and lowest tertiles of uninsured and Medicaid admissions, respectively. We compared patient demographics and hospital characteristics by safety-net status. Multivariable logistic regression models assessed adjusted odds of in-hospital mortality and 30- and 90-day readmission. RESULTS: About 304 080 patients were included in our analysis. On univariate analysis, high burden hospitals had higher inpatient mortality (2.06% vs 1.71%; P < .001) and 30 day- (16.3% vs 15.3%; P < .001) and 90-day readmission rates (24.6% vs 23.0%; P < .001). On multivariate analysis, high-burden status was not associated with significantly increased adjusted odds of inpatient mortality (OR, 1.047; 95% CI, 0.878-1.249), or readmission at 30 (OR, 1.035; 95% CI, 0.958-1.118) or 90 days (OR, 1.040; 95% CI, 0.968-1.117). CONCLUSION: SNHs do not have worse mortality and readmission outcomes following CABG, after adjusting for patient and hospital characteristics. These findings are reassuring regarding the quality of cardiac surgery care provided to underinsured patient groups. More research is needed to further elucidate trends in outcomes.

Insurance Status and Socioeconomic Factors Affect Early Mortality After Cardiac Valve Surgery.

OBJECTIVE: To characterize the effects markers of socioeconomic status (SES), including race and ethnicity, health insurance status, and median household income by zip code on in-patient mortality after cardiac valve surgery. DESIGN: Retrospective cohort study of adult valve surgery patients included in the State Inpatient Databases and Healthcare Cost and Utilization Project. The primary outcome was mortality during the index admission. Bivariate analyses and multivariate regression models were used to assess the independent effects of race and ethnicity, payer status, and median income by patient zip code on in-hospital mortality. DESIGN: Multistate database of hospitalizations from 2007 to 2014 from New York, Florida, Kentucky, California, and Maryland. PARTICIPANTS: In total, 181,305 patients ≥18 years old underwent mitral or aortic valve repair or replacement and met the inclusion criteria. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Mortality rates were higher among black (5.59%) than white patients (4.28%, p < 0.001) and among Medicaid (4.66%), Medicare (5.22%), and uninsured (4.58%) patients compared with private insurance (2.45%, p < 0.001). After controlling for age, sex, presenting comorbidities, urgent or emergent operative status, and hospital case volume, mortality odds remained significantly elevated for black (odds ratio [OR] 1.127, confidence interval [CI] 1.038-1.223), uninsured (OR 1.213, CI 1.020-1.444), Medicaid (OR 1.270, 95% CI 1.116-1.449) and Medicare (OR 1.316, 95% CI 1.216-1.415) patients. CONCLUSIONS: Markers of low SES, including race/ethnicity, insurance status, and household income, are associated with increased risk of in-hospital mortality following cardiac valve surgery. Further research is warranted to understand and help decrease mortality risk in underinsured, less-wealthy and non-white patients undergoing cardiac valve surgery.

Noteworthy Literature From 2019 for Cardiothoracic Critical Care.

This annual article summarizes key findings from notable studies published in 2019 relevant to the practice of cardiothoracic critical care medicine. This year's article encompasses updates to the literature on enhanced recovery after cardiac surgery, extracorporeal membranous oxygenation, delirium, and primary graft dysfunction after heart transplant.