Early and late acute kidney injury: temporal profile in the critically ill pediatric patient

Abstract

Background Increasing AKI diagnosis precision to refine the understanding of associated epidemiology and outcomes is a focus of recent critical care nephrology research. Timing of onset of acute kidney injury (AKI) during pediatric critical illness and impact on outcomes has not been fully explored. Methods Secondary analysis of the Assessment of Worldwide Acute Kidney Injury, Renal Angina, and Epidemiology (AWARE) database. AKI defined as per Kidney Disease Improving Global Outcomes (KDIGO) criteria. Early AKI defined as diagnosed at ≤48 hours after ICU admission, with any diagnosis >48 hours denoted as late AKI. Transient AKI defined as return to baseline SCr ≤48 hours of onset, and those without recovery fell into the persistent category. A second incidence of AKI ≥48 hours after recovery was denoted as recurrent. Patients were subsequently sorted into distinct phenotypes as early-transient, late-transient, early-persistent, late-persistent, and recurrent. Primary outcome was major adverse kidney events (MAKE) at 28 days or at study exit, with secondary outcomes including AKI-free days, ICU length of stay (LOS), and inpatient renal replacement therapy (RRT). Results 1,262 patients had AKI and were included. Overall mortality rate was 6.4% (n = 81), with 34.2% (n = 432) fulfilling at least one MAKE-28 criteria. The majority of patients fell in the early-transient cohort (n = 704, 55.8%). The early-persistent phenotype had the highest odds of MAKE28 (OR 7.84, 95% CI 5.45–11.3), and the highest mortality rate (18.8%). Oncologic and nephrologic/urologic comorbidities, at AKI diagnosis were associated with MAKE28. Conclusion Temporal nature and trajectory of AKI during a critical care course are significantly associated with patient outcomes, with several subtypes at higher risk for poorer outcomes. Stratification of pediatric critical care associated AKI into distinct phenotypes is possible and may become an important prognostic tool.

Impact of the Magnitude and Timing of Fluid Overload on Outcomes in Critically Ill Children: A Report From the Multicenter International Assessment of Worldwide Acute Kidney Injury, Renal Angina, and Epidemiology (AWARE) Study

“…Evaluation of the magnitude of FO over the temporal trajectory of an ICU stay may further delineate these targets for clinical intervention. A recent publication by Ruth et al (20) evaluated this concept as it pertains to acute kidney injury (AKI) in a secondary analysis of the Assessment of Worldwide Acute Kidney Injury, Renal Angina, and Epidemiology (AWARE) study. This study showed that factors such as timing, trajectory, duration, and magnitude of AKI collectively impact outcomes (20).…”

“…The AWARE study is an international multicenter study of critically ill children and young adults designed to evaluate the epidemiology and impact of AKI and FO (20,(23)(24)(25)(26)(27). This planned secondary analysis aims to: 1) describe the epidemiology of FO and 2) determine the association between FO magnitude (peak FO) and of FO ≥ 5% and FO ≥ 10% at the end of ICU Day1 and 2, with outcomes (AKI on day 3, 28-d ventilation-free days [VFDs], 28-d ICU-free days, and 28-d mortality).…”

The Neglected Price of Pediatric Acute Kidney Injury: Non-renal Implications

“…These definitions are agnostic to etiology, course, rate and degree of recovery, and timing of onset in relation to critical illness. Evidence is rapidly accumulating to indicate that severity is not the only dimension that has outcome implications; rather, timing of onset, duration, number of episodes, and rate of recovery, have discrete impacts on organ and global outcomes (21)(22)(23)(24)(25).…”

“…Renal recovery after AKI episodes is not always complete. Certain risk factors, such as extent of pre-morbid kidney health, repeat events, and underlying risk factors contribute to impaired recovery with long term consequences (22,23,25). About 10% of AKI survivors develop chronic kidney disease (CKD) (26)(27)(28)(29).…”

Fluid Overload Precedes and Masks Cryptic Kidney Injury in Pediatric Acute Respiratory Distress Syndrome

“…FO-adjusted creatinine, which corrects measured creatinine by degree of FO, has been shown to improve prediction of postoperative AKI in adults following cardiac surgery (16). Additionally, trajectories and durations of AKI have stronger associations with poor outcome than peak severity (17)(18)(19). Given the complex interrelatedness of FO, creatinine, AKI, and outcomes, it is possible that we are systematically underestimating the true burden of AKI due to the limitations of the definitions used.…”