289 - Hemostatic Changes After Initiating Pediatric Continuous Renal Replacement Therapy

Continuous renal replacement therapy (CRRT) is the dialytic therapy of choice for the most critically ill pediatric patient. Exposure to the foreign material in a CRRT circuit has been shown to activate the coagulation cascade leading to changes in hemostatic parameters in adults.  Within our < 10kg, pediatric CRRT population we have noted a decrease in platelets after CRRT initiation.


Objective: We assessed the impact of CRRT start on hemostatic parameters within a larger more heterogeneous critically ill pediatric CRRT cohort.

Design/Methods:

We included pediatric CRRT patients (< 18 years) between 2/2018-2/2020. Hematological data was collected prior to and 24 hours after CRRT start. We hypothesized a decrease in hemostatic parameters (platelets and fibrinogen) would occur after CRRT filter exposure.


Results:

Ninety-four patients (median age of 96 months (IQR 19.5 – 174) and weight 25 kg (13.4 – 50.8) had paired platelet values; 55 (59%) patients were thrombocytopenic (plt < 100 x10³/µL) prior to CRRT initiation with median of 73x10³/µL (43-175 x10³). Median platelet change was 4 x10³/µL (-16-45 x10³) with median platelet count of 68 x10³/µL (38-140 x10³) 24 hours after CRRT initiation. Forty-eight (51%) were on vasoactive medications, median PELOD-2 score was 7 (6-10).  There was no significant decrease in platelets after CRRT initiation.

Ninety-one patients had paired fibrinogen values. Median fibrinogen count was 264 mg/dL (165-435) before CRRT initiation and 256 mg/dL (150-356) 24 hours after CRRT start. There was not a significant decrease in fibrinogen after CRRT initiation. Only 17 (19%) patients had hypofibrinogenemia (fib < 150) prior to CRRT initiation.

We analyzed patients with decrease in platelets and fibrinogen as a sensitivity analysis. Forty-one (37%)  patients had a decrease in platelets; decrease in platelet count was associated with respiratory (p=0.001) and renal/urologic (p=0.02) comorbidities. Thirty-nine (43%) patients had a decrease in fibrinogen after CRRT initiation. A decrease in fibrinogen was associated with primary cardiac diagnosis (p < 0.001) and/or metabolic/endocrine comorbid conditions (p=0.02).

 


Conclusion(s): Decrease in platelet and fibrinogen levels after exposure to CRRT filter is uncommon in pediatric patients. However, a subset had a decrease in platelet count and fibrinogen levels. This case mix appears to differ based on associated comorbid conditions. Future work should further delineate the changes in hemostatic parameters in the context of transfusion exposure in the pediatric CRRT population.