23/154 Point of care Doppler ultrasound prior to emergency scrotal exploration

Introduction

The aim of the HTA Programme is to ensure that high quality research information on the clinical effectiveness, cost-effectiveness and broader impact of healthcare treatments and tests are produced in the most efficient way for those who plan, provide or receive care from NHS and social care services. The commissioned workstream invites applications in response to calls for research on specific questions which have been identified and prioritised for their importance to the NHS, patients and social care.

Research question

What is the diagnostic accuracy of scrotal point-of-care Doppler ultrasound (POCUS) carried out by a member of the initial assessment team prior to emergency scrotal exploration?

1. Technology: Doppler point-of-care ultrasound (POCUS) performed by an accredited assessing team (surgeon, emergency medicine doctor, radiologist).
2. Patient group: Patients of any age, presenting acutely with testicular pain and suspected testicular torsion in whom a decision for scrotal exploration has been made. Applications are encouraged which include recruitment from geographic populations with high disease burden which have been historically underserved by research activity in this field.
3. Setting: Emergency or any other suitable setting.
4. Reference standard: Scrotal exploration.
5. Study design: Diagnostic test accuracy study.
6. Important outcomes: Measures of diagnostic test accuracy of POCUS (including, but not limited to, sensitivity, specificity, positive and negative predictive values, likelihood ratios, diagnostic odds ratio).
7. Other outcomes: Inter- and intra-rater reliability; proportion of negative explorations that could have been safely avoided if decisions had been made using the ultrasound scan; value of clinical features as predictors of testicular torsion in patients presenting with acute scrotal pain; a composite score, utilising clinical and radiological features to predict the likelihood of testicular torsion in a given patient; training requirements for surgeons and emergency medicine physicians to become competent in the performance and interpretation of POCUS; costs; patient/parent/carer and clinician acceptability. Applicants should consider subgroup analyses as appropriate. Existing Core Outcomes should be included amongst the list of outcomes unless a good rationale is provided to do otherwise.
8. Minimum duration of follow-up: Until outcome of surgical exploration.

Rationale

In patients presenting with new onset scrotal pain, testicular torsion (twisting) is routinely suspected. Testicular torsion is one of the most important urological emergencies in which the blood supply to the testis can become reduced. In the worst-case scenario, this can result in the loss of the testis for affected patients.

Traditionally, to assess the cause of pain, patients undergo an emergency surgical exploration of the scrotum in the operating theatre. If the cause is testicular torsion, the testis is untwisted to preserve the blood supply and fixed to prevent re-twisting. However, in the majority of patients who undergo surgical exploration, torsion is not found.

The European Association of Urology guidelines state that Doppler ultrasound is useful to evaluate acute scrotum, with good diagnostic accuracy reported in the literature. In contrast, UK guidelines from the Royal College of Surgeons of England state that 'in patients with a history and physical examination suggestive of torsion, imaging studies should not be performed as they may delay treatment, therefore prolonging the ischaemic time'.

One of the major factors limiting use of ultrasound in patients with suspected torsion is that access to radiologists performing emergency scrotal ultrasound in the UK is variable, particularly out-of-hours. However, if the clinician assessing the patient was able to perform a point-of-care ultrasound (POCUS) of the scrotum when first seeing the patient, this may help to increase the use of prompt ultrasound, without introducing delay into the pathway, to decide on the need for surgical exploration. This could therefore reduce and avoid unnecessary surgical explorations. The clinician assessing the patient could be any one of a urological, general or paediatric surgeon, emergency medicine doctor or radiologist depending on local resources and time of the day.

The current approach exposes several thousand patients every year to potentially unnecessary surgical, anaesthetic risk and anxiety, as well as potential long-term effects, such as chronic scrotal pain. Furthermore, emergency explorations represent a significant use of NHS resources: occupying emergency operating theatres, theatre personnel and potential utilisation of overnight hospital beds.

The participants of the proposed study will be treated as usual; in addition, they will undergo point-of-care ultrasound examination prior to surgery. If ultrasound is proven to help detect or exclude testicular torsion, this research could result in substantial reductions of scrotal explorations and associated risks that patients are exposed to. The HTA Programme wishes to fund the study outlined above to inform clinical practice and future guidance in this clinical area.

Additional commissioning brief background information

A background document is available that provides further information to support applicants for this call. It is intended to summarise what prompted the call and the existing evidence base, including relevant work from the HTA and wider NIHR research portfolio. It was researched and written on the basis of information from a search of relevant sources and databases, and in consultation with a number of experts in the field. If you would like a copy please email htaresearchers@nihr.ac.uk.

Making an application

If you would like to apply for this call, you can begin your application via the funding opportunity page.

Your application must be submitted online no later than 1pm on 28 March 2024. Applications will be considered by the HTA Funding Committee at its meeting in May 2024.

Guidance notes and supporting information for HTA Programme applications are available.

Shortlisted Stage 1 applicants will be given 8 weeks to submit a Stage 2 application. The Stage 2 application will be considered at the Funding Committee in September 2024.

For commissioned topics, the Programme strongly discourages the practice of the same co-applicant joining more than one competing team, other than in unusual circumstances (for example, a lead from a named charity or a unique national expert in a condition).

For such exceptions, each application needs to state the case as to why the same person is included. The shared co-applicant should not divulge application details between teams, and both teams should acknowledge in their application that they are aware of the situation, and that study details have not been shared.

Should you have any queries please contact htacommissioning@nihr.ac.uk.