3 Committee considerations

Issues considered in this guidance

3.1

The following issues of clinical and decontamination practice were considered in terms of clinical and cost effectiveness, patient safety and the extent to which they reduce the risk of Creutzfeldt–Jakob disease (CJD) transmission:

  • use of reusable and single-use instruments in surgical procedures

  • arrangements for cleaning, sterilising and tracking of reusable surgical instruments.

Issues not considered in this guidance

3.2

The following issues were not considered in this guidance:

  • Transfusion of blood or blood products, including occupational exposure to blood or body fluids. Several organisations provide advice on measures to reduce the risks from blood transfusion and exposure to blood in the workplace, including the Department of Health and Social Care Advisory Committee on the Safety of Blood, Tissues and Organs (SABTO), and the Advisory Committee on Dangerous Pathogens' Transmissible Spongiform Encephalopathies subgroup.

  • Extracorporeal life-support machinery, including cardiopulmonary bypass, haemodialysis and ventilator equipment.

  • The risk of CJD and variant CJD (vCJD) transmission through drugs, which is regulated by the Medicines and Healthcare products Regulatory Agency (MHRA).

  • The safety of transplant grafts, which is the responsibility of the Department of Health and Social Care and SABTO.

  • The decontamination and reuse of single-use instruments, for which the MHRA has issued guidance advising against the reuse of such items.

  • General dentistry.

The evidence

3.3

For detailed information on the evidence see the University of Sheffield's School of Health and Related Research (ScHARR) systematic review, which consists of the following evidence:

  • Direct evidence is limited because of the rare nature of CJD. Eight systematic reviews on the incidence and prevalence of CJD in the general population in the UK, risk of transmission through surgery, incubation periods, infectivity, efficacy of decontamination procedures, adherence to NICE guidance by keeping surgical instrument sets together, complications from single-use instruments and the likelihood of patients who have had high-risk surgery returning for further surgery. The systematic reviews use historical case reports of surgically transmitted CJD (stCJD), observational data, case-control studies and animal studies. They are mostly descriptive, and no formal critical appraisal of study quality was done.

  • An updated version of the model used in NICE's previous appraisal of patient safety and reduction of risk of transmission of CJD (IPG196) to assess the cost effectiveness of potential strategies to reduce the risk of stCJD: the updated model assumes that all genotypes are susceptible to stCJD infection and that patients with stCJD can be misdiagnosed with an alternative neurodegenerative disease. A calibration of predicted model inputs was done with the number of possible stCJD cases observed between 2005 and 2018. All assumptions and the calibration were agreed with the CJD advisory subcommittee. A formal elicitation exercise with members of the CJD advisory subcommittee was used to update the parameters used in the modelling.