This document discusses the importance of recognizing a "lactate gap" - a discrepancy between lactate levels measured by different analyzers - in diagnosing ethylene glycol poisoning. It describes two cases where patients presented with acidosis but very high lactate levels only on the Radiometer point-of-care analyzer, revealing ethylene glycol toxicity. The author emphasizes that a lactate gap can provide an early diagnosis and avoid delays in critical treatment for ethylene glycol poisoning. He concludes by stressing the importance of using multiple analyzers and considering all diagnostic clues when evaluating unclear causes of acidosis.

1. A (happy) error:
OR why you should “mind the gap”
Peter Brindley
Full Time Critical Care Doc
Other Stuff:
MD, FRCPC, FRCP-Edin, FRCP-Lond
Professor, Critical Care Medicine, Medical Ethics, Anesthesiology
brindley@ualberta.ca/@docpgb

2. Would the other Dr Brindley please
“stand up”
Dr Giles Brindley.
not related!
“Brindley dropped his pants before the audience
…a very respectable erection”

3. Our sensitive friend, Lactate
”
Impending collapse
Vulnerable patient
Early warning
Sensitive
Cheap
Immediate

4. • Pt intubted in ED d/t decr’d loc
• Sick (& pH<7) but not “lactate >40” sick
Case 1: Lactate >40 (x3)

5. • Minimal Hx
• Surgery prepared to operate
• To ICU for stabilization (& dx)
– Plasma/lab: lactate 1.5mmol/L; pH<7 (repeated)
– POC ABG (Bayer) lactate 2.0mmol/L; pH<7 (repeated)
– POC ABG (Radiometer) lactate 40mmol/L: pH<7 (repeated)
• Acidemia real; etiology “unreal”
Case 1: pH<7.0 WTF

6. “lactate Gap”= EG
• Increased Osm/ Osm gap
• Ethylene Gycol “rushed”…
…positive but took 2 hours
• Changed to IHD etc
• Patient recovered
– ICU x 7d, Dialysis x 14d

7. “Mind the gap”
• MIND THE (LACTATE) GAP:
– High false + lactate w Radiometer after EG
– But not with plasma or other POC
– Potential laparotomy (mortality)
– Potential delayed EG therapy (morbidity)

8. Case 2
• POC lactate >20, pH <7.2// iStat lactate N.
• “lactate gap”  1st bedside Dx of EG
• Immediate IHD
• Extubated/discharged within 48h
• …Many other examples

9. – “Lactate gap” can be used for good!
– Important given
•Denial; strange ODs
•Late presentations; Consequences of delay
– & YOU NEED TWO ANALYZERS

10. N.B: Use all diagnostic clues
• Look at this table on e-Bay.
• How can you tell it is being sold by a man?

12. Look at the mirror…..
If you post a picture on the internet…..
WEAR CLOTHES when taking the picture!

14. No such thing as personal opinion…
David Brindley PhD, DSc, FRS etc etc

15. Scientific Method

16. Using Brindley blood
• Added EG metabolites:
– Glycolate, Glyoxalate, Oxalate, (Formate).
• Tested on 5 common analyzers:
– Radiometer (POC),
– Beckman (lab),
– Vitros (lab)
– Bayer, (POC)
– Istat (POC)

18. EG NOT MT

19. Insert Heritage Picture
CMAJ 2007: 176(8): 1097
Q.E.D

21. And enjoy the gap

22. Many thx
Now please disagree
brindley@ualberta.ca
@docpgb