Change in alkaline phosphatase activity associated with intensive care unit and hospital length of stay in patients with septic acute kidney injury on continuous renal replacement therapy.

BACKGROUND: Evidence suggests that alkaline phosphatase attenuates inflammatory response in sepsis by lipopolysaccharide detoxification and adenosine triphosphate dephosphorylation. We sought to determine changes in alkaline phosphatase (AP) activity during septic acute kidney injury (AKI) and clinical parameters associated with AP activity. METHODS: In this retrospective study, we investigated baseline (when initiating CRRT) and follow-up AP activity on day 3, and associated outcomes in patients who underwent continuous renal replacement therapy (CRRT) due to septic AKI. RESULTS: We analyzed the baseline AP activity of 155 patients and day 3 AP activity in 123 patients. Baseline AP activity was not associated with renal or inflammatory biomarkers, or outcomes. It did not significantly differ between the 75 survivors and 80 non-survivors (p = 0.155). AP activity was higher on day 3 than at baseline (105 U/L [interquartile range, 79-156] vs 90 U/L [interquartile range, 59-133]). In particular, liver and bone isoforms increased significantly (p < 0.05), but intestine isoforms did not reach statistical significance (p = 0.367). In addition, day 3 AP activity showed a weak correlation with length of ICU stay (r = 0.213, p = 0.018) and length of hospital stay (r = 0.216, p = 0.017), but not with survival (r = - 0.035, p = 0.698). CONCLUSION: Endogenous AP activity significantly increased in patients with septic AKI. However, neither baseline nor follow-up AP activity was associated with survival.

Predictive Factors of Duration of Continuous Renal Replacement Therapy in Acute Kidney Injury Survivors.

The factors influencing continuous renal replacement therapy (CRRT) duration for critically ill patients with acute kidney injury (AKI) are unclear. Therefore, we investigated the clinical factors that could influence the duration of CRRT for AKI survivors. In this retrospective observational study, the medical records of all hospital survivors who required CRRT for AKI in intensive care units were analyzed. The CRRT duration (median, 6 days) was categorized as short-duration CRRT (≤ 6 days, n = 65) and long-duration CRRT (> 6 days, n = 59), according to the median CRRT duration. A urine output of less than 0.5 mL/kg/h (adjusted odds ratio [OR], 3.4; P = 0.010), mechanical ventilation use (adjusted OR, 7.9; P = 0.001), and extracorporeal membrane oxygenation (ECMO) use (adjusted OR, 6.5; P = 0.010) were independent predictors of long-duration CRRT, whereas serum creatinine and neutrophil gelatinase-associated lipocalin were not significant predictors. A clinical model demonstrated a good discriminatory ability to predict long-duration CRRT (area under the curve, 0.84; 95% confidence interval, 0.76-0.90). The urine output immediately before CRRT initiation and factors associated with disease severity significantly affected the duration of CRRT. Simultaneously considering the urine output, mechanical ventilation use, and ECMO use predicted CRRT duration in AKI survivors.

Early continuous renal replacement therapy in septic acute kidney injury could be defined by its initiation within 24 hours of vasopressor infusion.

PURPOSE: The optimal timing for the initiation of early continuous renal replacement therapy (CRRT) is uncertain and requires a practically feasible definition with acceptable evidence. MATERIALS AND METHODS: We investigated the clinical impacts of 3-time interval parameters on the morbidity and mortality of 177 patients with septic shock-induced acute kidney injury: (1) time from vasopressor initiation to CRRT initiation (Tvaso-CRRT), (2) time from intensive care unit (ICU) admission to CRRT initation (TICU-CRRT), and (3) time from endotracheal intubation to CRRT initiation (Tendo-CRRT). RESULTS: The proportion of the patients with Tvaso-CRRT less than 24 h (median, 14 h, interquartile range [IQR], 5-30 h) was significantly higher in the survival group than in the non-survival group (84.3% vs. 58.5%, p < 0.001). Tvaso-CRRT less than 24 h and Sequential Organ Failure Assessment score were independent factors associated with 28-day mortality and 90-day mortality. TICU-CRRT (median, 17 h, IQR, 5-72 h) and Tendo-CRRT (median, 13 h, IQR, 4-48 h) were significantly correlated with both the length of ICU stay (p < 0.001) and mechanical ventilation duration (p < 0.001), but not mortality. CONCLUSIONS: Considering the possible therapeutic measurement by physician on the basis of the results in this study, early CRRT could be defined by a Tvaso-CRRT less than 24 h.