#NephMadness 2019: Bowman’s Bracketology for Volume Assessment

Posted on March 25, 2019 by AJKDblog in NephMadness // 0 Comments

Brendan Bowman
Brendan Bowman is Associate Professor of Medicine at the University of Virginia. He is the Medical Director of the UVA dialysis program, co-director of the renal physiology course, and provides inpatient nephrology consultation in the ICU. He once made his high school junior varsity basketball team…but never saw the floor!

Competitors for the Volume Assessment Region

Old School vs New School

Dry on Dialysis vs Wet on Dialysis

This year’s Volume Assessment region wraps all the drama of NephMadness into one corner of your bracket: a young gun upstart out to prove itself, a classic powerhouse, and a Cinderella story some say snuck into the tournament. Let’s go matchup by matchup:

Old School vs New School

There is no more hand-wringing chairside experience than volume assessment. Our classic physical exam and vitals assessment techniques are older than Naismith himself. The Old Schoolers say their approach has been getting the job done for years – why change now? Others say vital sign interpretation and physical examination in patients on dialysis are hopelessly confounded by medication timing and comorbidities. But before your write off the old schoolers, they have one more trick play to call: protocolized ultrafiltration. In the DRIP trial, participants underwent successful serial target weight reduction resulting in improved blood pressure control. Target weight was achieved when the patient developed symptoms of volume depletion. Despite the weight of experience on this team, a paucity of supporting studies for the classic approach leaves this team vulnerable to upset.

The New Schoolers wield a re-tooled volume assessment offense – borrowing some tricks they learned playing in our sister league – the ICU. Bioimpedance and ultrasound-based techniques are most familiar to clinicians, but these have been generally thought unwieldy and impractical for daily use. In the fast-breaking world of dialysis, efficiency is prized. However, innovations like point-of-care ultrasound probes that connect to smartphones overcome the practicality argument, allowing dialysis units to maintain a smooth transition game from weigh-in to target weight adjustment. Just like their opponent, the new schoolers have a surprise play in their game plan: noninvasive cardiac output monitoring. This technique uses alternating current to evaluate stroke volume, calculate cardiac output, and determine a patient’s fluid responsiveness. Unfortunately for team New School, some of their best data are in the ICU league, not dialysis. No one knows if they’ll be run out of the gym now that they’re in the big dance.

Dry on Dialysis vs Wet on Dialysis

At first glance, this doesn’t even seem much of a matchup. What chance does an undersized squad from a small town like Team Wet on Dialysis have against the juggernaut that is Team Dry on Dialysis? Team Dry has been running over opponents for years with the obvious benefits of volume control. The negative consequences of volume overload are legion: increased hospitalization rates, left ventricular hypertrophy, and increased mortality, to name a few. This was the end of the story until a few teams scouted a weakness in Team Dry’s game plan – excessive ultrafiltration rates are associated with increased mortality. This has been a game-changing concept as evidenced by ultrafiltration rate’s inclusions as a reporting measure in the Quality Incentive Program (QIP) in its freshman season! Couple this with an increasing emphasis on the patient’s experience of care – meaning reducing dialysis related cramping, myalgias and nausea, and all of a sudden, Team Wet looks like a sleeper pick to go far in this tournament!

– Guest Post written by Brendan Bowman

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