# Macrovascular and Microvascular Response to Fluid Removal during Hemodialysis for Acute Kidney Injury

> **NIH NIH K23** · UNIVERSITY OF PENNSYLVANIA · 2022 · $189,721

## Abstract

Project Summary
Over 13 million people develop acute kidney injury (AKI) each year. AKI increases the risk of incident chronic
kidney disease, end-stage kidney disease, and death. Fluid removal (ultrafiltration) is an important component
of managing dialysis-requiring AKI (AKI-D), but safe achievement of optimal volume status involves a delicate
balance between preventing fluid overload and avoiding circulatory compromise. Acuity of illness and comorbid
conditions render patients with AKI highly susceptible to even modest hemodynamic changes, and routine
blood pressure monitoring may be inadequate to detect subtle, yet clinically meaningful, perfusion changes
during hemodialysis. Continuous monitoring of systemic or local tissue perfusion is feasible using a variety of
near-infrared optical technologies, but there has been limited application of these devices during hemodialysis
particularly in the setting of AKI. The overarching premise of this proposal is that optimizing fluid management
in an already vulnerable AKI population requires (1) a marker that captures an individualized hemodynamic
response to fluid removal throughout hemodialysis treatments, and (2) more sensitive techniques to detect
hypoperfusion. Funded by an F32 award, Dr. Wang previously leveraged continuous hematocrit monitoring
(CHM) during maintenance hemodialysis treatments to calculate a semi-instantaneous plasma refill rate
(PRR), which refers to the rate of refilling of the vascular space from the interstitial space during ultrafiltration.
Through this K23 proposal, Dr. Wang will extend her investigations of PRR to the AKI setting and will evaluate
novel approaches to assessing perfusion during hemodialysis. Specifically, Dr. Wang will perform mediation
analysis using data from a large cohort of patients on maintenance hemodialysis to determine whether PRR
mediates the effects of treatment-related factors on intradialytic hypotension (Aim 1); and, in a prospective
cohort of patients with AKI-D, she will combine continuous hematocrit monitoring with two noninvasive
techniques – diffuse correlation spectroscopy and diffuse optic spectroscopy ‒ to simultaneously measure
changes in systemic perfusion (Aim 2) and cerebral perfusion and oxygenation (Aim 3) as a novel approach to
elucidate the physiology underlying both overt and subtle hemodynamic effects of hemodialysis. Additionally,
she will use bedside testing to link spatiotemporal changes in tissue physiology with changes in cognitive
function. To conduct this work, Dr. Wang will utilize the formal methodologic training and practical experience
in epidemiology, study design, and longitudinal analysis that she acquired through the Master of Science in
Clinical Epidemiology Program. Through her K23 career development plan, she will gain (1) skills in designing
and implementing prospective studies in dialysis, (2) experience studying outcomes in acute care, and (3)
expertise in advanced methods for analyzing multidimensional...

## Key facts

- **NIH application ID:** 10447162
- **Project number:** 5K23DK129770-02
- **Recipient organization:** UNIVERSITY OF PENNSYLVANIA
- **Principal Investigator:** Christina Hao Wang Brotman
- **Activity code:** K23 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2022
- **Award amount:** $189,721
- **Award type:** 5
- **Project period:** 2021-07-01 → 2026-04-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10447162

## Citation

> US National Institutes of Health, RePORTER application 10447162, Macrovascular and Microvascular Response to Fluid Removal during Hemodialysis for Acute Kidney Injury (5K23DK129770-02). Retrieved via AI Analytics 2026-05-22 from https://api.ai-analytics.org/grant/nih/10447162. Licensed CC0.

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