ED Toxicology

Purpose:
ED Toxicology is available as part of a comprehensive suite of programmes for the Clinical Laboratory to cover all of its basic core tests. These include: Serum Chemistry, Urine Chemistry, ED Toxicology, Lipids, Bilirubin and Serum Indices.

Ethanol, paracetamol and salicylate are frequent tests ordered in the Emergency Department as part of the investigation of the unconscious patient or in suspected overdose cases. Ethylene glycol, Methanol and Whole Blood Ethanol were added to this scheme in response to the ‘NHS services, Seven Day Working’ from NHS England. The Association for Clinical Biochemistry and Laboratory Medicine published guidance on the clinical Biochemistry tests that may be required for the optimal clinical management of ‘Critical’ and ‘Urgent’ patients. They recommended that Ethanol, Methanol and Ethylene Glycol be included as ‘Urgent’ tests and should be available within 4 hours.

Scope:
Four human serum and whole blood samples are distributed monthly, with a minimum of 48 samples distributed over the year covering a wide range including samples at the clinically important decision points. The samples consist of a panel of 8 linearly related samples where salicylate, paracetamol and ethanol have been added gravimetrically to “off the clot” serum from healthy volunteers tested negative for these analytes. The linear panel are distributed on a number of occasions over that period which are used to assess both laboratory and method performance, including linearity, bias, within and between batch imprecision. Separate samples are available for serum Ethylene glycol and Methanol and for Whole Blood Ethanol.

Key Features:

Toxic pathological range covered, cut-off levels where clinical decisions can have serious consequences for the patient.
Liquid human serum samples. Linearly related panel covering the analytical and Toxic pathological range.
Samples assess both laboratory and method performance, including linearity, bias, within and between batch imprecision.
Challenging samples at clinically relevant cut-off concentrations.

Frequency:
Monthly

Samples:
4 x 1.0mL
Whole Blood Ethanol 4 x 0.5mL

Material:
Off the clot human serum and whole blood

ED Toxicology Programme
Analyte	Approx. Range Covered
Salicylate	0 - 800	mg/L
Paracetamol	0 - 350	mg/L
Ethanol	0 - 4500	mg/L
*Ethylene Glycol	0 - 3000	mg/L
*Methanol	0 - 2500	mg/L
Whole Blood Ethanol	0 - 4500	mg/L