Association Between Acute Kidney Injury Duration and Outcomes in Critically Ill Children.

OBJECTIVES: Acute kidney injury occurs frequently in children during critical illness and is associated with increased morbidity, mortality, and health resource utilization. We aimed to examine the association between acute kidney injury duration and these outcomes. DESIGN: Retrospective cohort study. SETTINGS: PICUs in Alberta, Canada. PATIENTS: All children admitted to PICUs in Alberta, Canada between January 1, 2015, and December 31, 2015. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: In total, 1,017 children were included, and 308 (30.3%) developed acute kidney injury during PICU stay. Acute kidney injury was categorized based on duration to transient (48 hr or less) or persistent (more than 48 hr). Transient acute kidney injury occurred in 240 children (77.9%), whereas 68 children (22.1%) had persistent acute kidney injury. Persistent acute kidney injury had a higher proportion of stage 2 and stage 3 acute kidney injury compared with transient acute kidney injury and was more likely to start within 24 hours from PICU admission. Persistent acute kidney injury occurred more frequently in those with higher illness severity and in those admitted with shock, sepsis, or with a history of transplant. Mortality varied significantly according to acute kidney injury status: 1.8% of children with no acute kidney injury, 5.4% with transient acute kidney injury, and 17.6% with persistent acute kidney injury died during hospital stay (p < 0.001). On multivariable analysis adjusting for illness and acute kidney injury severity, transient and persistent acute kidney injury were both associated with fewer ventilation-free days at 28 days (-1.28 d; 95% CI, -2.29 to -0.26 and -4.85 d; 95% CI, -6.82 to -2.88), vasoactive support-free days (-1.07 d; 95% CI, -2.00 to -0.15 and -4.24 d; 95% CI, -6.03 to -2.45), and hospital-free days (-1.93 d; 95% CI, -3.36 to -0.49 and -5.25 d; 95% CI, -8.03 to -2.47), respectively. CONCLUSIONS: In critically ill children, persistent and transient acute kidney injury have different clinical characteristics and association with outcomes. Acute kidney injury, even when its duration is short, carries significant association with worse outcomes. This risk increases further if acute kidney injury persists longer independent of the degree of its severity.

Reduction in hospital mortality over time in a hospital without a pediatric medical emergency team: limitations of before-and-after study designs.

OBJECTIVE: To determine whether hospital mortality has decreased over time in a hospital that has not introduced a pediatric medical emergency team (PMET). DESIGN: Retrospective observational study. SETTING: Quaternary children's hospital. PARTICIPANTS: All pediatric inpatient separations (defined as any discharge, including death) during 10 fiscal years. MAIN OUTCOME MEASURES: We searched our hospital administrative database to determine the number of pediatric inpatient separations and deaths, and we searched the hospital switchboard and pediatric intensive care databases to determine ward code and cardiopulmonary arrest rates. Relative risks (RRs) with 95% confidence intervals (CIs) and logistic regression compared results over time. RESULTS: During the periods of the 2 PMET studies showing a reduction in hospital mortality, we found a decrease in hospital mortality: for 1999-2002 vs 2002-2006, 212 deaths among 14 161 patients (1.50%) vs 219 of 26 767 (0.82%), RR, 0.55 (95% CI, 0.44-0.69); for 2000-2005 vs 2005-2007, 300 deaths among 29 497 patients (1.02%) vs 98 of 14 005 (0.70%), RR, 0.69 (95% CI, 0.55-0.86). During the periods of the 3 PMET studies showing no change in or not examining hospital mortality, we found no significant change in hospital mortality. The annual odds ratio for survival was 1.13 (95% CI, 1.09-1.16). There were no changes in ward code and cardiopulmonary arrest rates over time. CONCLUSIONS: We found a reduction in hospital mortality over time in a children's hospital without a PMET. This demonstrates the limitation of before-and-after study designs, and we hypothesize that multiple co-interventions account for the decrease in mortality. Whether a PMET could have reduced mortality further is unknown.