This document discusses the case of a 34-year-old male found unconscious after ingesting radiator fluid. The patient presents with coma, hypothermia, respiratory distress, renal failure, and a high anion gap metabolic acidosis. Laboratory findings include an elevated osmolal gap and normal arterial blood gases. The registrar analyzes the patient's condition and laboratory results, determining the likely diagnosis is ethylene glycol poisoning presenting late with complications including aspiration pneumonia and renal failure. Immediate management should include interventions for hypothermia, renal replacement therapy, and antidote therapy with fomipizole or ethanol infusion.

1. Case Discussion
Muhammad Asim Rana
BSc, MBBS, MRCP, MRCPS, FCCP, EDIC, SF-CCM
Department of Critical Care Medicine
King Saud Medical City
Comatose Patient

2. Clinical Summary
• You are the on call ICU Registrar and are
covering the night shift.
• You have almost finished your energy reserves
at around 4 am, after finishing wards round
and just came back to the ICU doctors room
and thrown your self in chair when the bleep
rings
Why does Asim like such worst scenarios always?

3. History
• 34 years old male Indian patient
• Car mechanic by profession
• Brought to A & E by Red Crescent
• No past medical history
• No attendant available.
• Patient was found unconscious in the workshop and
they found empty bottle of radiator fluid near him.
• ER called MSP and he has called you as patient is
unconscious

4. Dilemma continues
• ER and MSP are looking at you to take him to
ICU because of low conscious level.
• What you are supposed to do?
1. Fight with ER & MSP that why they have not
assessed the case before calling you
2. Read the file……
3. Call your senior
4. Start examining the patient
Very Bad Senior Again!!!

5. Causes of COMA
Structural
OR
Surgical
•DIFFUSE DAMAGE TO BOTH
HEMISPHERES
•VASCULAR DAMAGE
• INCREASED ICP
Metabolic
OR
Medical
Diffuse insult to both cerebral
hemispheres by toxins, either
from within or from outside

6. Alcohol
Epilepsy/Exposure
Insulin(Diabetic)
Overdose/Oxygenlow
Uremia(kidneyfailure)
Trauma/HeadInjury
InfectionorIatrogenic
Psychosisorpoisoning
Strokes
A E I O U T I P S
Causes of COMA

7. Clinical Summary
• You see him wearing a single T-Shirt and Trousers with very
cold weather out side, otherwise GPE is unremarkable. You
are told pt has been having diarrhea
• Vitals:
– Temp 32:C, BP 130/85, HR 129/min regular, SpO2 87% on 10
liters per min NRM
• CNS:
– GCS: E1M5V2
– No lateralization
– No signs of meningeal irritation
– Pupils bilaterally constricted equal and reactive
– Bilateral up going planters

8. Clinical Summary
• Cardiovasular Exam:
– Unremarkable except for tachycardia, auscultation
normal
• Abdomen:
– Unremarkable, the patient vomited while you were
examining the abdomen-coffee ground
• Respiration:
– Decreased Rt sided movements with decreased air
entry on Rt lower zone especially in Rt axillary area
with coarse crepts and broncheal breathing

9. Chest X-Ray

10. Laboratory Investigations
• CBC.. Hb% 14, WBCs 12, Platelets 230
• Na 140. K 6.6, Cl 109, Blood Glucose 200mg%
• BUN 28, Creatinine 344
• CK 8700, ALT 77, AST 92, ALP 150, Billir 17
• Amylase 23, Lipase 12
• Hepatitis viral markers negative
• HIV negative

11. Whatyouwilldonow? • Think of the steps you have to take as
an Intensivists:
• Need to know Diagnosis or ???
• Intubation and securing the airway?
• Reviewed the labs… What next?
• Looked at CXR.. What is this?
• What next?
• What antibiotics?
• What we are missing?
• Hypothermia needs attention or NO?

12. What else do you need?
Ct Brain Normal
CSF analysis
Proteins 34, LDH 12, Sugar 67mg% (RBS
200mg%),
Cell count 3, all lymphocytes.
Latex negative

13. Any thing else you would ask for?
ABGs:
pH 7.77, PaCO2 35.5, PaO2 57, HCO3 50.6
Check Internal data for consistency
[H+]= 24 x PaCO2/HCO3
24 x 35.5/50.6= 16.8
[H+]=7.8-pH x 100
7.8-7.77x 100= 3

14. Venous Blood Gas Repeated
• pH 6.878, PaCO2 20, PaO2 27.2, HCO3 4
• What is the impression now?
• How do we analyze the Blood Gas results?
• The six steps approach
• Although there is much to discuss about
reading blood gases…

15. Step-wise Approach
1. Acedemia or Alkalemia
2. Metabolic or Respiratory
3. For metabolic is it anion gap or non anion
gap.
4. For anion gap acidosis,is it associated with
other disturbances.
5. What is the respiratory compensation for the
metabolic disturbances.
6. For respiratory disturbances is it acute or
chronic.

16. Step-wise Approach
• Step1:
• Acidemia or Alkalemia?
• Acidemia
• Step2:
• Metabolic or Respiratory?
• Metabolic
• Step3:
• Is there anion gap or no?
• 140-109+4=27
• Yes high anion gap metabolic acidemia

17. High Anion Gap Metabolic Acidemia
• M
• U
• D
• P
• I
• L
• E
• S

18. High Anion Gap Metabolic Acidemia
• Methanol
• Uremia
• DKA
• Paraldehyde
• Ischemia, Iron, INH, Isopropyl alcohol
• Lactic acidosis
• Ethylene glycol
• Salicylates

19. Back to Brain Exercise
• What could be the cause in our patient?
• Yes, He might be a case alcohol ingestion!!
• Which Alcohol?
• Methanol, Ethanol, Ethylene glycol, Isopropyl
Alcohol
• How will you proceed further?
• Check Serum Osmolality, Urine for?
• Why & which one,.. Calculated or measured?

20. Continue The Thinking Process
• Osmolal Gap =
Measured osmolarity - Calculated osmolarity
Normal 0 - 10. Abnormal > 10.
• Calculated osmolarity =
2 x (Na+) + BUN/2.8 + Glucose/18

21. Move your Brain Cells
Na+ = 140, Glucose = 200, BUN = 28
Measured serum osmolality = 310
• Osmolal gap = Measured OSM - Calculated OSM:
= 310 - (2x140 + 200/18 + 28/2.8)
= 310 - (280 + 11 + 10)
= 310 - 301
= 9 Now What There is NO Osmolal Gap?

22. Remember!!!
• All alcohols are osmotically active
• Methanol and Ethanol are characterized by
– High Anion Gap Acidosis
– Osmolal gap
• Only methanol and ethanol are metabolized to
acids
• Isopropyl Alcohol is metabolized to acetone.
• Ethylene glycol may be metabolized completely
to toxic metabolized not active osmotically….
Normal Osmolal gap..
• Late presentation!!!!

23. Remaining steps of ABGs analysis
• Is the respiratory compensation adequate?
• Winter formula
• Exp pCO2 = [1.5(measured HCO3
-)]+8± 2
• Exp pCO2 = [1.5(3.7)]+8±2= 13.5 ±2
• So what is this?
• Respiratory element !!!
• Why?
• Low GCS and Chest problem infective process

24. Remaining steps of ABGs analysis
• Are there any other metabolic disturbances?
• Corrected HCO3
- = Measured HCO3
- + Delta gap
• Delta Gap?
• Calculated Anion Gap – Normal Anion Gap
• Corrected HCO3= ( AG-12) +Measured HCO3
• 24=(AG-12)+Measured HCO3
• 24=(27-12)+Measured HCO3
• 24=(15)+4= 19
• This stays less than 24… So what does it mean?
There is additional
non anion gap metabolic
acidosis
What could be the reason?

25. Normal Anion Gap Acidosis
(Hypokalemia)
• Diarrhea
• Ureteral diversion
• Renal tubular
acidosis
– Proximal
– Distal
• Mineralcorticoid
deficiency
• Carbonic anydrase
inhibitor
– Acetazolamide
– Mefenamic acid
• Post hypocapneic
state

26. Normal Anion Gap Acidosis
(Hyperkalemia)
• Early renal failure
• Renal disease
–SLE interstitial
nephritis
–Amyloidosis
–Hydronephrosis
–Sickle cell
nephropathy
• Acidifying agents
–Ammonium
chloride
–Calcium chloride
–Arginine
• Sulfur toxicity

27. Summary of Assessment
• Case of alcohol ingestion(Ethylene Glycol) with
complications masking the clinical picture
• Late presentation
• Aspiration pneumonia
• Early Renal Failure
– Rhabdomyolysis
– Ethylene Glycol
• Hypothermia

28. Management
• Which of the following interventions is most
likely to benefit this patient?
1. IV fluids (Crystalloids)
2. Ethanol infusion
3. Fomipizole
4. Thiamine
5. Haemodialysis

29. Hope we conveyed the message
Thank you for your patience