Despite calling it “laboratory error”, a lot of the problem happens long before the sample gets to the lab. #NKFClinicals
75% of errors happen before sample gets to the lab! #NKFClinicals
It is almost never an analytical issue. Because these guys are careful.
Case 1/6 K was 6 and normal in ER, this happens every January. The outpatient winter K is too high. He was symptomatic. Also occurs with sister.
Familial Pseudohyperkalemia, they have fast leak in response to cooling and time.
If you spin the sample first to separate the cells from the plasma.
Case 2/6
Unexplained low CO2 in an infant
History of diarrhea
First sample 11 2 hours later it was 18.
The small ample in a big tube allows CO2 to escape resulting in artifact.
Case 3
Elevations in lactate of 10 after surgery
On antibiotics.
Not concordat with clinical picture
Routine labs and ABG
3 days and 8 doctors to figure out they were drawing the labs downstream from an LR infusion 🤦🏼♂️ #NKFClinicals
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Michael Emmett on electrolyte artifacts
Pre-analytical and analytical #NKFClinicals
Starting with pseudohyponatremia
These are real cases
The osmolality was 294, so there is a huge gap. 44ish
Implies Artifactual decrease in sodium
Her triglycerides were >6000 #NKFClinicals
Note the different between HCO3 and tCO2 should be closer than 19 and 9. #NKFClinicals
I presented a poster at #NKFClinicals. This came from working with ViforCSL on the KALM-1 and KALM-2 meta-analysis of the pivotal trials of difelikefalin for CKD associated pruritus (CKDaP). About a year ago we brainstomed what other lessons could we could pull from the data.
A question we had was how quickly do people respond to the drug, or put more practically, if you start a patient on difelikefalin and a month later they are still having intense itch, how likely will it be that they still could respond?
Look at the only figure on the poster and focus on the bars, this gives the fraction of people who will ultimately respond to difelikefalin who have responded at 4 weeeks, 8 weeks and 12 weeks.
Never in the history of medicine has so much been done, by so many, so incompetently, with so little consequence as in the treatment of severe hyponatremia. #Tweetorial 1/10
You shouldn't correct hyponatremia too fast. The speed limit is 8 mmol/L per day. We are terrible at it. In George et al, 41% of 1,490 pts were corrected faster than 8 mEq/L. Look at the poor slobs at the left of the nomogram whose Na actually went down 🤪 2/10
Thankfully this incompetence is rarely punished. Of the 611 (41% of 1490) patients who over-corrected in the George trial, only 7 developed osmotic demyelination syndrome (ODS). Screw the sodium correction and you can get away with it 99% of the time. 3/10
The begining of my medical career was dominated by HIV
Start med school in 91. Magic Johnson announces he is HIV+
MS3 med students do blood draws on HIV+ patients (phlebotomy refuses)
MS4 lost my first patient, advanced dementia HIV
Graduated in '95, peak HIV, 50k US deaths
The whole clincal world was HIV, but you would go to the textbooks and they would still be calling HIV HLTV3. It was bonkers. It was in this envirnoment that UpToDate crushed Harrisons.
Then during residency HAART emerges and the whole thing melts away in a matter of years. All that knowledge about opportunistic infections becomes less a critical part of IM and selective ID knowledge.