musings of a salt whisperer
This noon comference was not done by me but by Dr. Steigewalt. The whole team was there.
Dr. Steigerwalt provided some great handouts:
We are going to study renal and patient survival in our CKD clinic. One of our team members who is charged with creating the data capture form wanted to look at prior form. So here it is.
Today’s journal club was on Aliskiren (Tekturna)combined with Losartan versus Losartan alone from the NEJM and Benazepril + Amlodipine (Lotrel) versus ACEi + HCTZ (Lotensin HCT) from KI. Both studies use change in albuminuria for the primary endpoint.
The Aliskiren study had an expected outcome. The shocker would have been if it had gone the other way. The surprising thing was how close they came to showing an actual decrease in progression (p=0.07) in only 6 months and with only 600 patients. Looks like aliskiren + ARB is a lock to slow the progression to doubling of creatinine and prevention of dialysis.
The Guard study was a surprise because the old generic lowered albuminuria more than the new hotness Lotrel. A lot of spin in the discussion on why that may have occurred.
One of my (soon to be former) fellows wanted a copy of this work-sheet handout on electrolyte free water clearance.
Yesterday we discussed the problem with the curvilinear relationship between gfr and creatinine and how the MDRD equation dispenses with this problem. Today we will go over a handout introducing GFR, MDRD and how to manage them, including referral to a nephrologist.
Additionally I want to do my canned acute renal failure lecture. This lecture has been made obsolete by the recent ATN data and data from Vanderbilt so it will need to be revised.
I love it when some of the arcane nephrology knowledge makes headlines. When I heard NPR covering hyponatremia I almost cried. I am training for a half marathon in October and so I have been thinking about this topic.
Almond, Et al’s study published in the NEJM looked at 488 blood samples from 766 runners recruited from the 2002 Boston Marathon. They found post-race:
When they looked at predictors of hyponatremia, univariate predictors included:
Of note use of sport drinks compared to pure water made no difference. In the multivariate analysis, hyponatremia was associated with:
Of note the female gender falls out in the multivariate analysis as it likely was accounted for both by the longer running time and lower BMI.
In the discussion the authors mention that most sport drinks have only 18 mmol/L of Na.
On Monday one of our interns gave a lecture on the range of renal pathology possible found with lupus nephritis.
This was a follow up on her lecture on the renal manifestations of lupus nephritis by WHO criteria. After her lecture we went down to bowels of the hospital to look at the kidney biopsy we had done on Friday on one of our patients with lupus.
Just got my second rhabdomyolysis patient in the last 2 months. Both had anuric acute renal failure and both had CPKs over 100,000.
In fellowship, the dogma was that sodium bicarbonate was ineffective and could do harm. The reasoning was that alkalinizing urine made calcium-phosphate less soluble, increasing the likelihood of calcification in the tubule extending the renal damage.
Recently, I found a paper from the Journal of Trauma 2004 by Brown and Rhee (Alternative) which showed compelling trends for improved outcomes with mannitol and bicarbonate. What was so impressive to me was that as the disease got more severe (higher CPK) the experimental group appeared to do relatively better. The authors were prevented from reaching a significant p value primarily by having too few patients with severe rhabdo.
I will use the handout from a prior morning report on the subject for the teaching session on Monday.
This month I’m attending on the renal ward at Saint John Hospital and Medical Center. I have a huge team: one fellow, one second year resident, three interns (2 categorical and one ER resident) and two medical students. I have been having a blast teaching them.
I am going to track all of the teaching I do this month here.
So far this is the formal (as opposed to bedside) teaching we have done:
Monday June 2: Introduction to Two-Ell
Tuesday June 3: Nephrotic Syndrome
Wednesday June 4: Dialysis basics and Anti-hypertensive agents saves lives
Thursday June 5: Renal Adventures in Imaging (the nephrologic implications of Gadolinium and NFD, phosphate nephropathy as a complication of colonoscopy prep, and contrast nephropathy)
More to come.