Specimen Collection

• DO NOT SWAB THE VENEPUNCTURE SITE WITH ALCOHOL.

Sample stability:

• 2 days at 25 ^o C
• 2 weeks at 5 ^o C
• 4 weeks at -15 ^o C

4.5 mL Adult PST Blood (Preferred)

5 mL Heparin Blood

4 mL Plain Blood

0.5 mL Paediatric Microsample

0.5 mL Paediatric Micro-heparin Plasma

0.5 mL Paediatric Micro-PST Plasma
Reference Intervals

Units: mmol/L

11 -22	patients usually have signs of intoxication including impaired judgement, increase reflex time and decrease reaction time
> 22	patients usually have signs suggesting depression of the central nervous system.
> 88	fatalities have been reported with serum alcohol above this level. It has been reported that the lethal level for 50% of nonalcohol dependent population is at 98mmol/L although individuals have survived levels as high as 326mmol/L

This test is NOT accepted for medico-legal purposes.

Conversion factor:

for ethanol: mg/100 mL = mmol/L x 4.6

Uncertainty of Measurement: 10% below the level of 10mmol/L

5% at the levels of 50 mmol/L and higher

Turnaround Time: Within 3 hours
Assay Method

Principle : Enzymatic

Reagents: Roche ETOH2 kit

Analyser: Cobas c502

Diagnostic Use and Interpretation

Ethanol measurement may be useful for judging whether the level of unconsciousness can be explained by the alcohol concentration alone, or whether some other toxicological cause should be sought. (see ranges above).

The current (from 1 Dec 2014) legal driving limit for adult is 10.9 mmol/L (50 mg/100mL). Prior to 1 Dec 2014 the limit was 17.4mmol/L (80 mg/100ml).

Rate of metabolism : ethanol is eliminated at a constant rate between 2.4 and 4.8 mmol/L per hour, depending on the individual.

References:

Kurt C Kleinschmidt in Ethanol Chapter 31 p.593 in Haddad and Winchester's Clinical Management of Poisoning and Drug overdose 4th edition 2007 Shannon MW, Borron SW, Burns MJ (eds) Saunders Elsevier

Contact Information

Emails to chemicalpathologist@adhb.govt.nz will receive priority attention from the on-call chemical pathologist.

If the query concerns a specific patient please include the NHI number in your email.

If email is not a suitable option, please contact the on-call chemical pathologist via Lablink (Auckland City Hospital ext. 22000 or 09-3078995).

Individual chemical pathologists may be contacted but will not be available at all times.

After-hours : contact Lablink (Auckland City Hospital ext. 22000 or 09-3078995) or hospital operator for on duty staff after hours.

Dr Samarina Musaad (Clinical Lead) : SamarinaM@adhb.govt.nz ext. 22402

Dr Cam Kyle: CampbellK@adhb.govt.nz ext 22052

Dr Weldon Chiu: WeldonC@adhb.govt.nz ext. 23427

Dr Campbell Heron: CHeron@adhb.govt.nz ext. 23427

Dr Sakunthala Jayasinghe: Sakunthala@adhb.govt.nz ext. 23427

Last updated at 15:26:00 06/01/2025