Vallabhajosyula, Saraschandra

Background: The objective of this study was to characterize patients with hyponatremia at hospital admission into clusters using an unsupervised machine learning approach, and to evaluate the short- and long-term mortality risk among these distinct clusters. Methods: We performed consensus cluster analysis based on demographic information, principal diagnoses, comorbidities, and laboratory data among 11,099 hospitalized adult hyponatremia patients with an admission serum sodium below 135 mEq/L. The standardized mean difference was utilized to identify each cluster’s key features. We assessed the association of each hyponatremia cluster with hospital and one-year mortality using logistic and Cox proportional hazard analysis, respectively. Results: There were three distinct clusters of hyponatremia patients: 2033 (18%) in cluster 1, 3064 (28%) in cluster 2, and 6002 (54%) in cluster 3. Among these three distinct clusters, clusters 3 patients were the youngest, had lowest comorbidity burden, and highest kidney function. Cluster 1 patients were more likely to be admitted for genitourinary disease, and have diabetes and end-stage kidney disease. Cluster 1 patients had the lowest kidney function, serum bicarbonate, and hemoglobin, but highest serum potassium and prevalence of acute kidney injury. In contrast, cluster 2 patients were the oldest and were more likely to be admitted for respiratory disease, have coronary artery disease, congestive heart failure, stroke, and chronic obstructive pulmonary disease. Cluster 2 patients had lowest serum sodium and serum chloride, but highest serum bicarbonate. Cluster 1 patients had the highest hospital mortality and one-year mortality, followed by cluster 2 and cluster 3, respectively. Conclusion: We identified three clinically distinct phenotypes with differing mortality risks in a heterogeneous cohort of hospitalized hyponatremic patients using an unsupervised machine learning approach.

Acute myocardial infarction with cardiogenic shock (AMI-CS) is associated with high mortality and morbidity despite advancements in cardiovascular care. AMI-CS is associated with multiorgan failure of non-cardiac organ systems. Acute kidney injury (AKI) is frequently seen in patients with AMI-CS and is associated with worse mortality and outcomes compared to those without. The pathogenesis of AMI-CS associated with AKI may involve more factors than previously understood. Early use of renal replacement therapies, management of comorbid conditions and judicious fluid administration may help improve outcomes. In this review, we seek to address the etiology, pathophysiology, management, and outcomes of AKI complicating AMI-CS.

Summary Background Hospitalized patients with hyperkalemia are heterogeneous, and cluster approaches may identify specific homogenous groups. This study aimed to cluster patients with hyperkalemia on admission using unsupervised machine learning (ML) consensus clustering approach, and to compare characteristics and outcomes among these distinct clusters. Methods Consensus cluster analysis was performed in 5133 hospitalized adult patients with admission hyperkalemia, based on available clinical and laboratory data. The standardized mean difference was used to identify each cluster’s key clinical features. The association of hyperkalemia clusters with hospital and 1-year mortality was assessed using logistic and Cox proportional hazard regression. Results Three distinct clusters of hyperkalemia patients were identified using consensus cluster analysis: 1661 (32%) in cluster 1, 2455 (48%) in cluster 2 and 1017 (20%) in cluster 3. Cluster 1 was mainly characterized by older age, higher serum chloride and acute kidney injury (AKI), but lower estimated glomerular filtration rate (eGFR), serum bicarbonate and hemoglobin. Cluster 2 was mainly characterized by higher eGFR, serum bicarbonate and hemoglobin, but lower comorbidity burden, serum potassium and AKI. Cluster 3 was mainly characterized by higher comorbidity burden, particularly diabetes and end-stage kidney disease, AKI, serum potassium, anion gap, but lower eGFR, serum sodium, chloride and bicarbonate. Hospital and 1-year mortality risk was significantly different among the three identified clusters, with highest mortality in cluster 3, followed by cluster 1 and then cluster 2. Conclusion In a heterogeneous cohort of hyperkalemia patients, three distinct clusters were identified using unsupervised ML. These three clusters had different clinical characteristics and outcomes.

Introduction: Intracranial hemorrhage (ICH) is associated with high mortality rate of 30-52% despite current advances in management. New cardiovascular abnormalities (CA), such as EKG or cardiac biomarker abnormalities ensue in ICH and are postulated to be due to hypothalamic injury and catecholamine surge. These CA are thought to portend a poor prognosis. Methods: We evaluated clinical studies reporting CA in ICH and assessing their effect on mortality. Studies without a control group, pediatric, and non-English literature were excluded. We extracted data on demographics, comorbidities and mortality [in-hospital (IHM), 30 day (30M) and 90 day (90M)]. CA data included EKG changes (bradycardia, atrial fibrillation, bundle branch blocks, QTc prolongation, ST-segment depression, and ST-segment elevation), biomarker elevation (troponin-T (TnT), CK-MB and BNP), and wall motion abnormalities (WMA). Unadjusted and adjusted rates for CA and pooled risk ratio (RR) with 95% CI were calculated using Mantel-Haenszel random effects model for mortality. Results: We reviewed 453 studies, of which 26 met our inclusion criteria. Heterogeneity varied from moderate to severe depending on the outcome chosen. Of a total 5580 patients, 2796 (50.1%) had sub-arachnoid hemorrhage (SAH), 1633 ICH (29.3%) and 1151 (20.6%) both. The incidence of CA is presented in Table 1. Of these 26 studies, 19 evaluated the influence of new CA on mortality. IHM was noted in 175/566 (30.9%) and 491/2496 (19.7%) patients with and without CA, respectively. In addition, 30M and 90M were noted in 18/38 (47.4%) vs. 14/136 (10.3%) and 90/175 (51.4%) vs. 247/1139 (21.7%) patients with and without CA, respectively. CA was associated with worse IHM (RR 2.03, 95% CI 1.58-2.62, p<0.001), 30M (RR 3.18, 95% CI 1.86-5.42, p<0.001) and 90M (RR 2.11, 95% CI 1.44-3.08, p<0.001) in patients with ICH compared to those who did not have CA. Conclusion: CA are common in patients with ICH and are associated with worse IHM, 30M and 90M.

Introduction: Lactate is a known prognostic marker in critically ill patients, including patients with shock and cardiac arrest (CA). We sought to describe the association between admission lactate and hospital mortality in cardiac intensive care unit (CICU) patients, particularly those with CA. Methods: We retrospectively evaluated adult patients admitted to a tertiary care CICU from January 1, 2007, to April 30, 2018, with measured lactate on admission. We examined hospital mortality as a function of admission lactate level in patients with and without CA. Multivariable logistic regression was used to determine predictors of hospital mortality in the overall cohort, after adjustment for clinical characteristics, therapies, and illness severity. Results: We included 3,042 patients with a median age of 70 years (IQR 60-80), including 40.5% (n=1,233) females. There were 789 patients (26.1%) with a diagnosis of CA. The median APACHE-4 predicted mortality was 24.2% (IQR 10.9-50.7), and 50.8% (n=1546) were treated with vasoactive infusions. The median lactate on admission was 1.8 mmol/L (IQR 1.1-3.0). CICU mortality occurred in 478 (15.7%) patients) and hospital mortality occurred in 706 (23.2%) patients. Hospital mortality rose progressively as a function of admission lactate ( Figure ). On univariable analysis, lactate was associated with increased hospital mortality among the overall cohort (OR 1.36, CI 1.31-1.42, P < .001; AUROC 0.71), patients with CA (OR 1.33 (95% CI 1.25-1.41, P < .01; AUROC 0.73), and patients without CA (OR 1.27, CI 1.21-1.34, P < .01; AUROC 0.64). On multivariable analysis, lactate was one of the most significant predictors of hospital mortality (adjusted OR 1.13 per mmol/L, 95% CI 1.08-1.18, P < .001). Conclusions: Admission lactate levels are strongly associated with increased hospital mortality among CICU patients, especially those with CA. The prognostic value of lactate levels may help inform clinicians caring for CICU patients.

Background The role of race and ethnicity in the outcomes of cardiac arrest (CA) complicating acute myocardial infarction (AMI) is incompletely understood. Methods and Results This was a retrospective cohort study of adult admissions with AMI‐CA from the National Inpatient Sample (2012–2017). Self‐reported race/ethnicity was classified as White, Black, and others (Hispanic, Asian or Pacific Islander, Native American, Other). Outcomes of interest included in‐hospital mortality, coronary angiography, percutaneous coronary intervention, palliative care consultation, do‐not‐resuscitate status use, hospitalization costs, hospital length of stay, and discharge disposition. Of the 3.5 million admissions with AMI, CA was noted in 182 750 (5.2%), with White, Black, and other races/ethnicities constituting 74.8%, 10.7%, and 14.5%, respectively. Black patients admitted with AMI‐CA were more likely to be female, with more comorbidities, higher rates of non–ST‐segment–elevation myocardial infarction, and higher neurological and renal failure. Admissions of patients of Black and other races/ethnicities underwent coronary angiography (61.9% versus 70.2% versus 73.1%) and percutaneous coronary intervention (44.6% versus 53.0% versus 58.1%) less frequently compared to patients of white race ( p <0.001). Admissions of patients with AMI‐CA had significantly higher unadjusted mortality (47.4% and 47.4%) as compared with White patients admitted (40.9%). In adjusted analyses, Black race was associated with lower in‐hospital mortality (odds ratio [OR], 0.95; 95% CI, 0.91–0.99; P =0.007) whereas other races had higher in‐hospital mortality (OR, 1.11; 95% CI, 1.08–1.15; P <0.001) compared with White race. Admissions of Black patients with AMI‐CA had longer length of hospital stay, higher rates of palliative care consultation, less frequent do‐not‐resuscitate status use, and fewer discharges to home (all P <0.001). Conclusions Racial and ethnic minorities received less frequent guideline‐directed procedures and had higher in‐hospital mortality and worse outcomes in AMI‐CA.

Background There are limited contemporary data on the use of emergent coronary artery bypass grafting (CABG) in acute myocardial infarction. Methods and Results Adult (aged >18 years) acute myocardial infarction admissions were identified using the National (Nationwide) Inpatient Sample (2000–2017) and classified by tertiles of admission year. Outcomes of interest included temporal trends of CABG use; age‐, sex‐, and race‐stratified trends in CABG use; in‐hospital mortality; hospitalization costs; and hospital length of stay. Of the 11 622 528 acute myocardial infarction admissions, emergent CABG was performed in 1 071 156 (9.2%). CABG utilization decreased overall (10.5% [2000] to 8.7% [2017]; adjusted odds ratio [OR], 0.98 [95% CI, 0.98–0.98]; P <0.001), in ST‐segment–elevation myocardial infarction (10.2% [2000] to 5.2% [2017]; adjusted OR, 0.95 [95% CI, 0.95–0.95]; P <0.001) and non–ST‐segment–elevation myocardial infarction (10.8% [2000] to 10.0% [2017]; adjusted OR, 0.99 [95% CI, 0.99–0.99]; P <0.001), with consistent age, sex, and race trends. In 2012 to 2017, compared with 2000 to 2005, admissions receiving emergent CABG were more likely to have non–ST‐segment–elevation myocardial infarction (80.5% versus 56.1%), higher rates of noncardiac multiorgan failure (26.1% versus 8.4%), cardiogenic shock (11.5% versus 6.4%), and use of mechanical circulatory support (19.8% versus 18.7%). In‐hospital mortality in CABG admissions decreased from 5.3% (2000) to 3.6% (2017) (adjusted OR, 0.89; 95% CI, 0.88–0.89 [ P <0.001]) in the overall cohort, with similar temporal trends in patients with ST‐segment–elevation myocardial infarction and non–ST‐segment–elevation myocardial infarction. An increase in lengths of hospital stay and hospitalization costs was seen over time. Conclusions Utilization of CABG has decreased substantially in acute myocardial infarction admissions, especially in patients with ST‐segment–elevation myocardial infarction. Despite an increase in acuity and multiorgan failure, in‐hospital mortality consistently decreased in this population.

Background: This study aimed to determine the rates of inpatient palliative care service use and assess the impact of palliative care service use on in-hospital treatments and resource utilization in hospital admissions for hepatorenal syndrome. Methods: Using the National Inpatient Sample, hospital admissions with a primary diagnosis of hepatorenal syndrome were identified from 2003 through 2014. The primary outcome of interest was the temporal trend and predictors of inpatient palliative care service use. Logistic and linear regression was performed to assess the impact of inpatient palliative care service on in-hospital treatments and resource use. Results: Of 5571 hospital admissions for hepatorenal syndrome, palliative care services were used in 748 (13.4%) admissions. There was an increasing trend in the rate of palliative care service use, from 3.3% in 2003 to 21.1% in 2014 (p < 0.001). Older age, more recent year of hospitalization, acute liver failure, alcoholic cirrhosis, and hepatocellular carcinoma were predictive of increased palliative care service use, whereas race other than Caucasian, African American, and Hispanic and chronic kidney disease were predictive of decreased palliative care service use. Although hospital admission with palliative care service use had higher mortality, palliative care service was associated with lower use of invasive mechanical ventilation, blood product transfusion, paracentesis, renal replacement, vasopressor but higher DNR status. Palliative care services reduced mean length of hospital stay and hospitalization cost. Conclusion: Although there was a substantial increase in the use of palliative care service in hospitalizations for hepatorenal syndrome, inpatient palliative care service was still underutilized. The use of palliative care service was associated with reduced resource use.