Does continuous arterial blood pressure monitoring during surgery benefit patients who are high risk, particularly those who are older and living with frailty?

ISRCTN ISRCTN12558538
DOI https://doi.org/10.1186/ISRCTN12558538
IRAS number 351284
Secondary identifying numbers R&D 24/006
Submission date
10/07/2025
Registration date
09/09/2025
Last edited
09/09/2025
Recruitment status
Not yet recruiting
Overall study status
Ongoing
Condition category
Surgery
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data
Record updated in last year

Plain English summary of protocol

Background and study aims
Many people have low blood pressure during surgery, which can be harmful, especially for older or frail patients. This can affect important organs like the heart, kidneys, or brain. One way to help is by measuring blood pressure continuously during surgery using a drip in the wrist, instead of checking it every few minutes with a cuff. This might help doctors spot and treat low blood pressure more quickly. However, this method isn’t used often because there isn’t enough research to support it. This study aims to find out if continuous blood pressure monitoring during surgery helps high-risk patients, especially those having surgery for a broken hip.

Who can participate?
The study is for people aged 65 or older who are considered frail and need surgery for a broken hip.

What does the study involve?
Participants will be randomly placed into one of two groups. One group will have their blood pressure measured continuously during surgery using a drip in the wrist. The other group will have it measured at regular intervals using a cuff. Researchers will look at how well the study works, track blood pressure during surgery, check for any complications, and ask patients about their quality of life afterward.

What are the possible benefits and risks of participating?
The study may help improve care for future patients by showing whether continuous blood pressure monitoring is better. There may be some small risks from the drip used for monitoring, such as discomfort or infection, but these are rare and will be carefully managed.

Where is the study run from?
South Tees Hospitals NHS Foundation Trust (UK)

When is the study starting and how long is it expected to run for?
The study started in June 2025 and is expected to run until April 2028.

Who is funding the study?
National Institute for Health and Care Research (NIHR) (UK)

Who is the main contact?
Andrew Kane, andrew.kane@nhs.net

Contact information

Mr Andrew Kane
Public, Scientific, Principal Investigator

South Tees Hospitals NHS Foundation Trust
James Cook University Hospital
Marton Road
Middlesbrough
TS4 3BW
United Kingdom

ORCiD logoORCID ID 0000-0001-9488-4086
Phone +44 7709619017
Email andrew.kane@nhs.net

Study information

Study designA feasibility study consisting of an external multi-centre two-arm parallel-group assessor-blinded randomized pilot trial with a nested qualitative study
Primary study designInterventional
Secondary study designRandomised controlled trial
Study setting(s)Hospital
Study typePrevention, Safety
Participant information sheet To follow
Scientific titleContinuous ARterial monitoring in Elderly and Frail patients for hip fractUre surgery to prevent Low blood pressure
Study acronymCAREFUL
Study objectives1. To undertake a systematic review and meta-analysis to understand what is currently known regarding the use of continuous blood pressure monitoring and its impact on intra-operative hypotension and associated morbidity.
2. To understand clinician attitudes towards continuous arterial monitoring in older frail patients presenting for trauma surgery through questionnaires and focus groups.
3. To undertake a feasibility study with embedded qualitative research to assess whether a full-scale randomised controlled trial (RCT) of continuous invasive arterial blood pressure monitoring versus standard care is feasible in the older, frail patient population presenting for hip fracture surgery.
Ethics approval(s)

Not yet submitted, Ethics committee name not provided (Address not provided, City not provided, Zip/postal code not provided; Telephone number not provided; Email not provided), ref: 25/WA/0235

Health condition(s) or problem(s) studiedContinuous invasive arterial blood pressure monitoring during orthopaedic trauma surgery
InterventionStudy arms
Participants will be randomly allocated in a 1:1 ratio using block randomisation, stratified by site to either:
Continuous invasive arterial blood pressure monitoring
• Up to three attempts to establish continuous invasive arterial blood pressure monitoring using local anaesthesia before general or neuraxial anaesthesia.
• Continuous arterial blood pressure monitoring will be maintained until the patient reaches the recovery room, where it may be discontinued or continued at the discretion of the clinical team.
OR
Standard care
• 3-to-5-minute cycles of blood pressure monitoring.

Duration of treatment
Start: From the start of anaesthesia care.
End: The randomised treatment can be removed at a point the clinician feels is appropriate- normally in the recovery room.

Follow-up period
120 days from the day of surgery.

Randomisation
The randomisation schedule will be stratified by site and formed of randomly permuted blocks of randomly varying size using a 1:1 allocation ratio. The allocation sequence will be generated by a statistician not involved in the study and uploaded to the REDCap platform.
Following consent, randomisation will be performed immediately via the REDCap platform. Clinical teams will be informed as early as possible to allow planning of care.
Intervention typeProcedure/Surgery
Primary outcome measureFeasibility outcomes:
1. Site setup is measured using number of sites recruiting first participant at end of trial
2. Participant recruitment rate is measured using number of participants recruited per site per month at end of trial
3. Outcome follow-up data completeness is measured using proportion of participant-reported outcome data collected at 120 days
4. Intervention compliance is measured using proportion of participants receiving allocated treatment at end of trial
5. Treatment crossover is measured using proportion of patients not receiving allocated treatment at baseline and during hospital stay
6. Unblinding rate is measured using number of outcome assessors unblinded to trial allocation at 120 days
Secondary outcome measuresFeasibility of data collection of clinical and patient-reported outcome measures:
1. Pre-injury mobility is measured using patient or carer report at baseline
2. Pre-injury quality of life is measured using EuroQol EQ5D5L questionnaire at baseline
3. Pre-injury residential status is measured using patient or carer report at baseline
4. Delirium is measured using 4AT tool at baseline and on day 3 (+/-1 day) post-surgery
5. Comorbidities are measured using patient notes at baseline
6. Drug history is measured using patient notes at baseline
7. Routine blood test results are measured using full blood count, urea and electrolytes, clotting screen, CRP at baseline
8. Blood pressure is measured using standard clinical measurement on admission
9. ASA score is measured using anaesthetic chart at time of surgery
10. Type of anaesthetic is measured using anaesthetic chart at time of surgery
11. Volume of fluids administered is measured using anaesthetic chart during surgery
12. Units of blood products administered is measured using anaesthetic chart during surgery
13. Vasopressor and inotrope use is measured using anaesthetic chart during surgery
14. Estimated blood loss is measured using anaesthetic chart during surgery
15. Cardiac arrest is measured using anaesthetic chart during surgery
16. Death in theatre is measured using anaesthetic chart during surgery
17. Intra-operative blood pressure is measured using uploaded intra-operative measurements during surgery
18. First blood pressure in recovery is measured using standard clinical measurement in recovery room
19. Postoperative complications are measured using Comprehensive Complications Index at 120 days
20. Discharge destination is measured using patient notes at time of hospital discharge
21. Residential status is measured using patient or carer report at 120 days post-surgery
22. Mobility is measured using patient or carer report at 120 days post-surgery
23. Quality of life is measured using EuroQol EQ5D5L questionnaire at 120 days (+/-7 days) post-surgery
Overall study start date01/06/2025
Completion date01/04/2028

Eligibility

Participant type(s)Patient
Age groupSenior
Lower age limit65 Years
SexBoth
Target number of participants100
Key inclusion criteria1. ≥65 years old
2. Clinically frail – assessed as a Clinical Frailty Scale (CFS) Score of 5 or more
3. Primary proximal hip fracture (fractured neck of femur)
Key exclusion criteria1. Planned continuous arterial blood pressure monitoring or use of non-invasive blood pressure monitoring at a high frequency
2. Refusal to consent
Date of first enrolment01/10/2025
Date of final enrolment01/10/2027

Locations

Countries of recruitment

  • England
  • United Kingdom

Study participating centre

South Tees Hospitals NHS Foundation Trust
James Cook University Hospital
Marton Road
Middlesbrough
TS4 3BW
United Kingdom

Sponsor information

Funders

Funder type

Government

National Institute for Health and Care Research
Government organisation / National government
Alternative name(s)
National Institute for Health Research, NIHR Research, NIHRresearch, NIHR - National Institute for Health Research, NIHR (The National Institute for Health and Care Research), NIHR
Location
United Kingdom

Results and Publications

Intention to publish date30/12/2027
Individual participant data (IPD) Intention to shareYes
IPD sharing plan summaryPublished as a supplement to the results publication
Publication and dissemination planPlanned publication in a peer-reviewed journal. We will also hold a stakeholder event, including PPI representation, to disseminate findings, gather feedback and guide the development of a definitive study. We will communicate the results to the Centre for Peri-operative Care to inform future iterations of peri-operative guidelines for patients living with frailty. Findings will be presented at conferences and meetings (including RCoA and RCS events where team members regularly present), and feedback will be given to the PPI group. All WP will be published in peer-reviewed journals with open access. The aim will be to build engagement with clinicians who may become PIs.
IPD sharing planAll data generated or analysed during this study will be included in the subsequent results publication

Editorial Notes

24/07/2025: Trial's existence confirmed by the National Institute for Health and Care Research (NIHR) (UK).