Module - Drug Investigation (SLS125)

STP

Aim of this module

This module will provide the trainee with the knowledge and understanding of basic pharmacology and the mechanism of action of drugs. They will understand pharmacokinetics, pharmacogenomics and the criteria for valid therapeutic drug monitoring (TDM). They will optimise the use of commonly prescribed therapeutic drugs. They will be able to investigate the poisoned patient; screen for and confirm the presence of drugs of abuse. In the work-based module they will be expected to apply this knowledge as they learn to perform assays to assess therapeutic and toxic drugs using a range of methods and gain experience of the interpretation of results in a range of acute and chronic clinical conditions.

Work-based learning outcomes


  1. Perform a range of laboratory techniques used in the workplace to monitor therapeutic drug concentrations.
  2. Interpret the results of commonly used therapeutic drug monitoring (TDM) assays in the correct clinical context.
  3. Perform a range of laboratory and point-of-care techniques to investigate drugs of abuse and other toxic substances in cases of acute poisoning, and understand the clinical context in which such techniques can be useful.
  4. Decide the testing strategy for the investigation of patients taking drugs of abuse in the correct clinical and legal context.
  5. Decide the testing strategy for the investigation of the poisoned patient in the correct clinical and forensic context.
  6. Perform a range of pharmacogenetic tests.
  7. Interpret and report the results of analyses of drug abuse, poisons and pharmacogenetic tests in the correct clinical or forensic context.

Work-based Competencies


Learning outcome Title Knowledge
1 1,2

Perform the analyses to laboratory standard operating procedures for the following drugs:

  • digoxin and other cardioactive drugs
  • lithium
  • anticonvulsants
  • theophylline
  • ciclosporin and other immunosuppressive drugs.
  • The range of methods available for the individual drug analyses and the advantages/disadvantages of each method.
  • The principles of therapeutic drug monitoring (TDM); the criteria for valid TDM and the essentials of a TDM service.
  • For each drug selected:
    • its clinical use
    • pharmacokinetics – including common drug interactions
    • toxicity
    • monitoring therapy – including target ranges, recommended sampling times and sample types.
  • Mode of analysis (including advantages and disadvantages of the different methods in use).
2 1,3,4

Perform the analyses to laboratory standard operating procedures for drugs of abuse testing, including:

  • screening protocols
  • confirmation tests.
  • A selection of methods available for drugs of abuse analysis in both screening and confirmation testing and the advantages/disadvantages of each method.
  • Use of the following techniques:
    • immunoassay
    • POCT
    • thin layer chromatography
    • gas chromatography
    • high performance liquid chromatography
    • mass spectrometry.
  • Medico-legal considerations.
  • Specimen collection according to ‘chain of custody’ requirements.
  • Methods used to establish sample integrity and adulteration.
  • Screening and confirmation protocols, including qualitative, semi-quantitative and quantitative analysis.
  • Range of drugs commonly abused.
  • Metabolism of drugs commonly abused (including opiates and amphetamines).
  • Testing of patients on opiate maintenance or withdrawal therapy (methadone, buprenorphine).
  • Signs and symptoms of acute toxicity with identification of cases requiring urgent intervention and offer clinical advice on follow-up and/or further management.
3 1,3,5

Perform the analyses to laboratory standard operating procedures for drugs/toxins commonly found in overdose:

  • salicylates
  • paracetamol
  • ethanol
  • carbon monoxide.
  • The methods used for salicylate and paracetamol analysis in the base laboratory.
  • The methods used for ethanol and carbon monoxide, including laboratory and POCT techniques.
  • Specialist toxicological investigations and understand the protocol for the referral of samples to external laboratories.
  • The clinical signs and symptoms of individual drug toxicity and the expected pattern of laboratory results seen in cases of toxicity.
  • In-depth knowledge of sampling time requirements.
  • The identification of cases requiring urgent intervention, including knowledge of specific treatment protocols for paracetamol overdose.
4 1,3,5

Assist with two of the following analyses (following observation of a practitioner performing the relevant analysis):

  • toxic metals (Al, Fe, Hg, Pb)
  • ethanol
  • ethylene glycol, methanol and related alcohols
  • paraquat
  • organophosphorus insecticides or nerve agents.
  • The methods used for metal analysis (AAS, ICPMS, colorimetric).
  • Toxicological investigations and understand the protocol for the referral of samples to external laboratories.
  • The clinical signs and symptoms of individual poison toxicity and the expected pattern of laboratory results seen in cases of toxicity.
  • Sampling time requirements.
  • The identification of cases requiring urgent intervention, including specific treatment protocols and antidotes where available.
5 6

Assist with at least one of the following pharmacogenetic assays (following observation of performance by practitioner):

  • cholinesterase variants
  • TPMT
  • CYP variability in drug metabolism
  • Acetylation.
  • The methods used and their application.
  • The software packages to enable the use of pharmacokinetics.
6 1

Perform review of internal quality control (IQC) and external quality assessment (EQA) performance of a range of TDM and other drug assays.

  • The different EQA schemes and the scoring used in drug analysis.
  • The different cut-off levels used to assess drugs of abuse analysis (clinical versus workplace testing).
7 2,3,4,5,6

Identify cases that require urgent intervention and offer clinical advice on the follow-up and/or further management of the patient.

  • Time-critical and grossly abnormal results requiring urgent clinical interventions for the full range of investigations in this module.
  • Types and options for intervention, follow-up and clinical management and factors affecting their selection.
  • Responsibilities for follow-up, further management and interventions.
8 2,3,4,5,6

Interpret biochemical and toxicological data in light of the clinical details.

  • Correct use of data in relation to the full range of investigations specified within this module.
9 2,3,4,5,6

Draft written reports on investigations.

  • Requirements of report, including sources of information, appropriate use of patient records, reference materials and current national/international guidelines.

Work-based assessment


Complete 2 Case-Based Discussion(s)
Complete 2 of the following DOPS and/or OCEs
Type Title
DOPS Perform calibration and quality control of an automated analyser assay for a therapeutic drug
DOPS Perform screening tests for drugs of abuse
DOPS Refer drugs of abuse samples which test positive for confirmatory testing
DOPS Perform confirmatory testing for drugs of abuse samples
DOPS Select the sample type and preanalytical requirements and undertake the measurement of digoxin
DOPS Select the sample type and preanalytical requirements and undertake the measurement of an immunosuppressives drug
DOPS Select the sample type and preanalytical requirements and undertake the measurement of an antibiotic.
DOPS Identify refer and report toxicology samples which require urgent analysis at an external laboratory
DOPS Interpret an External Quality Assurance Report for an anticonvulsant
DOPS Interpret an External Quality Assurance Report for an immunosuppressant drug
DOPS Interpret an External Quality Assurance Report for an antibiotic
DOPS Perform a paracetamol assay
DOPS Perform an ethanol assay
OCE Discuss an abnormal paracetamol result and the therapeutic intervention with a healthcare professional