Validation of a Post-Filter Hematocrit Calculation Formula: A Comparative Analysis With Measured Post-Filter Hematocrit Values
Overview
- Phase
- Not Applicable
- Status
- Recruiting
- Sponsor
- Gwyndolyn M. Radford
- Enrollment
- 20
- Locations
- 1
- Primary Endpoint
- Agreement between measured and calculated post-filter hematocrit values.
Overview
Brief Summary
Filter clotting is a major complication of continuous renal replacement therapy (CRRT), resulting in blood loss, reduced treatment efficacy, and increased cost. One modifiable factor associated with filter clotting is filtration fraction (FF), or the proportion of plasma water being removed from the blood over the course of the filter. In convention, a cutoff of FF<20-30% has been used to prevent hemofilter clotting, but no evidence correlating FF with hemofilter clotting has been documented. Some experts have proposed that post-filter hematocrit (Hct) could be a more direct marker for determining hemofilter clotting risk, but evidence supporting clinical utility of this marker is lacking.
HCTpost=HCTpre/(FF(HCTpre-1)+1)
In our proposed validation study, we hope to determine whether our formula for post-filter Hct provides accurate results when compared to measured values. The information obtained from this study will potentially justify the use of utilizing the formula in future studies.
The procedure of this study is collecting blood samples from the post-filter lines of patients on CRRT at different time points and different flow rates. This will be considered the "measured post-filter hematocrit" which will then be compared to the calculated formula above, using the other values obtained from daily labs (for pre-filter hematocrit) and CRRT machine settings.
Detailed Description
This investigational study is listed as "other" because it is a validation study comparing two measurement methods-comparing a calculated versus a machine-measured post-filter hematocrit- and is typically classified as a cross-sectional investigational study in the context of diagnostic or method comparison research.
Study Design
- Study Type
- Interventional
- Allocation
- Na
- Intervention Model
- Single Group
- Primary Purpose
- Other
- Masking
- None
Eligibility Criteria
- Ages
- 18 Years to — (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •patients initiated on CRRT age equal than or greater to 18 years of age
Exclusion Criteria
- •patients on ECMO
Outcomes
Primary Outcomes
Agreement between measured and calculated post-filter hematocrit values.
Time Frame: Participation begins at consent and includes a single study procedure in which four post-filter blood samples are collected over ~40 minutes. Participation ends after the final draw. Generally, no longer than 1 day.
Use Bland-Altman analysis to assess agreement and quantify bias and limits of agreement. Calculate correlation coefficients (Pearson or Spearman) to evaluate the strength of association.
Secondary Outcomes
- Analyze the impact of CRRT settings on discrepancies between measured and calculated Filtration Fraction(Participation begins at consent and includes a single study procedure in which four post-filter blood samples are collected over ~40 minutes. Participation ends after the final draw. Generally, no longer than one day.)
- Subgroup analysis based on patient-specific factors(Participation begins at consent and includes a single study procedure in which four post-filter blood samples are collected over ~40 minutes. Participation ends after the final draw.)
Investigators
Gwyndolyn M. Radford
Principal Investigator
University of Iowa