Acute kidney injury occurs in about 10% of hospitalized patients, but what is less known is the amount of effort AKI consumes in a nephrologist’s day? Does hospital AKI spill over to outpatient follow-up? Do nephrologists use current guidelines in prescribing dialysis for AKI? All of these questions were unknown when the ASN’s AKI Advisory Group addressed the topic. In 2013 they launched a one-day survey on a day-in-the-life of AKI from the perspective of the kidney doctor. Dr. Sarah Faubel (SF) of the University of Colorado discussed their study with eAJKD advisory board member Dr. Joel Topf.
To listen to an audio version this interview is based on:
eAJKD: Please tell us about your study?
SF: As part of the AKI Advisory Group, we are interested in coming up with a way to highlight the burden of acute kidney injury. World Kidney Day in 2013 focused on acute kidney injury, and we thought that represented a nice opportunity to get a feel for what was going on in the United States with patients with AKI. We got the idea to survey ASN nephrologists to understand how many inpatient and outpatient AKI consults were being seen, and how many of these patients were in the ICU and on dialysis. The effort of the average nephrologist in the US in dealing with AKI was our most important question.
eAJKD: These seem like very fundamental questions about what nephrologists do. Why was this not known before 2013?
SF: Many studies have looked at the rate of AKI in hospital admissions using diagnostic codes and billing. To my knowledge, this is the first study using a survey of nephrologist to identify how many patients they are seeing for AKI versus ESRD versus other aspects of nephrology care. As far as I know, that information has not been available before.
eAJKD: What were the major findings of the study?
SF: Not to our surprise, AKI is the number 1 reason for inpatient consultation to a nephrologist (regardless being a teaching hospital or a non-teaching hospital).
eAJKD: The outpatient AKI burden found in the survey of the nephrologists was minimal. What did you think of those results?
SF: Based on USRDS database studies, it has been highlighted that AKI is not a major proportion of outpatient clinic visits. While 50% of the inpatient consults were AKI related, only 9% were outpatient related in our survey.
eAJKD: Based on your survey, a large portion of AKI patients were on dialysis, However, there were some real questions about the quality of the dialysis that we were providing for AKI. Can you elaborate on that?
SF: We found that among patients who were receiving renal replacement therapy for AKI, a fairly low percentage had an assessment of dose. Of the 414 patients who were on renal replacement therapy, only 48 calculated dialysis clearance. When we asked nephrologists to recall over the last year how often they assessed dose of dialysis, it was a pretty low percentage who routinely assessed doses as part of their practice.
eAJKD: A concern in my patients who are getting various amounts of fluid and are very catabolic in the ICU is whether I can trust the pre- and post- BUN to access Kt/V. Do I need a more sophisticated calculation?
SF: I think that’s a real problem, and many people have questioned the reliability of Kt/V assessments in that setting. However, in studies conducted using that measure, most would recommend a minimum threshold Kt/V of 1.3. In my own practice when I measure Kt/V in the acute setting, it’s universally lower than what I expected on the first treatments, usually around 1.0. In summary, we are not delivering the dose of dialysis that we should in our patients with AKI. But the reliability of that measurement is certainly fair to question.
eAJKD: Do US practices of AKI defer from rest of the world?
SF: ISN has a very ambitious goal in this area, and an important project is underway to determine the global burden of acute kidney injury. They have a goal called “0 by 25” that no patient will die or develop AKI that could have been prevented. This survey is looking at a number of preventable causes of AKI. For example, diarrheal illness would be a good case. The survey has been translated into multiple languages. It is trying to get a sense of the global burden of AKI and ways that people can intervene earlier and improve the care worldwide of patients with AKI.