Hospital case volume and clinical outcomes in critically ill patients with acute kidney injury treated with dialysis

Intensive Care Unit Volume of Sepsis Patients Does Not Affect Mortality: Results of a Nationwide Retrospective Analysis

BACKGROUND

There is little research evaluating outcomes from sepsis in intensive care units (ICUs) with lower sepsis patient volumes as compared to ICUs with higher sepsis patient volumes. Our objective was to compare the outcomes of septic patients admitted to ICUs with different sepsis patient volumes.

MATERIALS AND METHODS

We included all patients from the eICU-CRD database admitted for the management of sepsis with blood lactate ≥ 2mmol/L within 24 hours of admission. Our primary outcome was ICU mortality. Secondary outcomes included hospital mortality, 30-day ventilator free days, and initiation of renal replacement therapy (RRT). ICUs were grouped in quartiles based on the number of septic patients treated at each unit.

RESULTS

10,716 patients were included in our analysis; 272 (2.5%) in low sepsis volume ICUs, 1,078 (10.1%) in medium-low sepsis volume ICUs, 2,608 (24.3%) in medium-high sepsis volume ICUs, and 6,758 (63.1%) in high sepsis volume ICUs. On multivariable analyses, no significant differences were documented regarding ICU and hospital mortality, and ventilator days in patients treated in lower versus higher sepsis volume ICUs. Patients treated at lower sepsis volume ICUs had lower rates of RRT initiation as compared to high volume units (medium-high vs. high: OR = 0.78, 95%CI = 0.66-0.91, P-value = 0.002 and medium-low vs. high: OR = 0.57, 95%CI = 0.44-0.73, P-value < 0.001).

CONCLUSION

The previously described volume-outcome association in septic patients was not identified in an intensive care setting.

A Review on the Application and Limitations of Administrative Health Care Data for the Study of Acute Kidney Injury Epidemiology and Outcomes in Children

Administrative health care databases contain valuable patient information generated by health care encounters. These "big data" repositories have been increasingly used in epidemiological health research internationally in recent years as they are easily accessible and cost-efficient and cover large populations for long periods. Despite these beneficial characteristics, it is also important to consider the limitations that administrative health research presents, such as issues related to data incompleteness and the limited sensitivity of the variables. These barriers potentially lead to unwanted biases and pose threats to the validity of the research being conducted. In this review, we discuss the effectiveness of health administrative data in understanding the epidemiology of and outcomes after acute kidney injury (AKI) among adults and children. In addition, we describe various validation studies of AKI diagnostic or procedural codes among adults and children. These studies reveal challenges of AKI research using administrative data and the lack of this type of research in children and other subpopulations. Additional pediatric-specific validation studies of administrative health data are needed to promote higher volume and increased validity of this type of research in pediatric AKI, to elucidate the large-scale epidemiology and patient and health systems impacts of AKI in children, and to devise and monitor programs to improve clinical outcomes and process of care.

AKI Treated with Renal Replacement Therapy in Critically Ill Patients with COVID-19

BACKGROUND

AKI is a common sequela of coronavirus disease 2019 (COVID-19). However, few studies have focused on AKI treated with RRT (AKI-RRT).

METHODS

We conducted a multicenter cohort study of 3099 critically ill adults with COVID-19 admitted to intensive care units (ICUs) at 67 hospitals across the United States. We used multivariable logistic regression to identify patient-and hospital-level risk factors for AKI-RRT and to examine risk factors for 28-day mortality among such patients.

RESULTS

A total of 637 of 3099 patients (20.6%) developed AKI-RRT within 14 days of ICU admission, 350 of whom (54.9%) died within 28 days of ICU admission. Patient-level risk factors for AKI-RRT included CKD, men, non-White race, hypertension, diabetes mellitus, higher body mass index, higher d-dimer, and greater severity of hypoxemia on ICU admission. Predictors of 28-day mortality in patients with AKI-RRT were older age, severe oliguria, and admission to a hospital with fewer ICU beds or one with greater regional density of COVID-19. At the end of a median follow-up of 17 days (range, 1-123 days), 403 of the 637 patients (63.3%) with AKI-RRT had died, 216 (33.9%) were discharged, and 18 (2.8%) remained hospitalized. Of the 216 patients discharged, 73 (33.8%) remained RRT dependent at discharge, and 39 (18.1%) remained RRT dependent 60 days after ICU admission.

CONCLUSIONS

AKI-RRT is common among critically ill patients with COVID-19 and is associated with a hospital mortality rate of >60%. Among those who survive to discharge, one in three still depends on RRT at discharge, and one in six remains RRT dependent 60 days after ICU admission.

Interhospital Transfer and Outcomes in Patients with AKI: A Population-Based Cohort Study

BACKGROUND

Patients with AKI may require interhospital transfer to receive RRT. Interhospital transfer may lead to delays in therapy, resulting in poor patient outcomes. There is minimal data comparing outcomes among patients undergoing transfer for RRT versus those who receive RRT at the hospital to which they first present.

METHODS

We conducted a population-based cohort study of all adult patients (≥19 years) who received acute dialysis within 14 days of admission to an acute-care hospital between April 1, 2004 and March 31, 2015. The transferred group included all patients who presented to a hospital without a dialysis program and underwent interhospital transfer (with the start of dialysis ≤3 days of transfer and within 14 days of initial admission). All other patients were considered nontransferred. The primary outcome was time to 90-day all-cause mortality, adjusting for demographics, comorbidities, and measures of acute illness severity. We also assessed chronic dialysis dependence as a secondary outcome, using the Fine and Gray proportional hazards model to account for the competing risks of death. In a secondary post hoc analysis, we assessed these outcomes in a propensity score-matched cohort, matching on age, sex, and prior CKD status.

RESULTS

We identified 27,270 individuals initiating acute RRT within 14 days of a hospital admission, of whom 2113 underwent interhospital transfer. Interhospital transfer was associated with lower rate of mortality (adjusted hazard ratio [aHR], 0.90; 95% CI, 0.84 to 0.97). Chronic dialysis dependence was not significantly different between groups (aHR, 0.98; 95% CI, 0.91 to 1.06). In the propensity score-matched analysis, interhospital transfer remained associated with a lower risk of death (HR, 0.88; 95% CI, 0.80 to 0.96).

CONCLUSIONS

Interhospital transfer for receipt of RRT does not confer higher mortality or worse kidney outcomes.