Prognostic value of early hemodynamic improvement in patients with acute kidney injury and hemodynamic instability treated with continuous renal replacement therapy

Background

Since description of continuous renal replacement therapy (CRRT), these therapies provided improvement in hemodynamic parameters while reducing need for vasopressors in shock. Our aim is to determine whether hemodynamic improvement after 24 h of CRRT is a strong predictor of short term survival.

Methods

In a prospective observational study we enrolled 30 patients admitted to the intensive care unit (ICU)with acute kidney injury (AKI)and hemodynamic instability. AKI defined according to KDIGO criteria. All patients were subjected to continuous renal replacement therapy (CRRT). Based on the hemodynamic response 24 h after CRRT, patients were classified into responders (defined as having a 20% reduction in norepinephrine dosage or a 20% rise in MAP with no increase in norepinephrine), compared with nonresponders . All patients were followed up for 15 days after withdrawal of CRRT. Results of the 30 patients studied, 12 (40%) were responders and 18 (60%) were nonresponders. Responders showed higher mean arterial pressure and urine output during CRRT. SOFA score tended to increase significantly in nonresponders on day 3 (SOFA3) and day 4 (SOFA4) compared to nonresponders (P = 0.01, P = 0.001; respectively). During a 15 days follow-up period, the mortality rate among non responders was 100%, compared to 25% among responders (18 versus 3; P = 0.001).

Conclusion

Early hemodynamic improvement after CRRT is strong predictor of short term mortality. Of all scoring systems , post CRRT SOFA score is the most accurate prognostic indicator for mortality.