An interventional study of Fluid restriction and Free fluids in Fluid Overload and Congestive Heart Failure, sponsored by University College, London. Completed at 1 site in United Kingdom. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-02-06.
Sponsored by University College, London · Not applicable, Interventional, and Other
The aim of this feasibility study is to determine whether an alert embedded within the electronic health record (EHR) causes clinicians to enrol patients into a randomised controlled trial (RCT) comparing oral fluid restriction versus no restriction in patients admitted to hospital with fluid overload.
One of the main causes of fluid overload is heart failure where there is a lack of strong evidence to support the effectiveness of oral fluid restriction in the acute setting. This causes significant variation in clinical practice where decisions on whether or not to impose a restriction in oral fluid intake is based on the preference of the treating clinician rather than robust evidence from research.
THIRST Alert is a pragmatic randomised controlled trial (RCT), embedded in the EHR, which seeks to determine whether a computerised alert for the clinical team can change clinician behaviour during routine NHS care at University College London Hospitals NHS Foundation Trust (UCLH).
Patients with suspected fluid overload will be identified based on the prescription of intravenous furosemide, a medication used to stimulate diuresis (increased urine output) to remove excess fluid. A repeat prescription of intravenous furosemide within the first 48 hours of an unplanned admission will trigger the alert.
A clinician from the treating team will then be asked to consider enrolling the patient into the RCT if they judge that oral fluid restriction might be beneficial but they have uncertainty about this (clinical equipoise). Enrolled patients will be randomised to either oral fluid restriction of 1 litre per day or no fluid restriction. This will then be actioned through documenting as part of the clinical plan in the patients record and then communicated to the patient and the rest of the clinical team, including nursing staff.
The study will record the number of patients recruited into the trial and the effect of the alert on enrolled patients' subsequent oral fluid intake. There are no additional tests or follow up for patients and the trial finishes on discharge from the study site. All trial outcomes will use data collected from routine care and the study is supported by the UCLH Biomedical Research Centre, funded by NIHR.
Trial Design:
A single centre, pragmatic, parallel group randomised controlled trial and feasibility study. The study will be conducted entirely within University College Hospital, at University College London Hospitals NHS Foundation Trust.
Research Hypothesis:
Clinician-facing alerts, delivered through the electronic health records system, provide a feasible method of enrolling patients into pragmatic trials evaluating the effectiveness of routine treatments
Clinical Research question:
In hospitalised patients with fluid overload, does an automated clinician-facing computerised decision support system (CDSS) alert recommendation for either oral fluid restriction (to 1L per day) or no-fluid restriction (continue with free fluids) result in a change in clinical behaviour and change in the oral fluid intake of enrolled patients?
Study participants:
The study population will be patients treated for suspected fluid overload with a regular prescription of intravenous (IV) furosemide within 48 hours of an unplanned hospital admission.
For staff participants, any clinician with prescribing rights for IV furosemide may be exposed to the CDSS alert. For subsequent medical staff, nursing staff and other allied health professionals, patient enrolment into the trial and their treatment allocation status will be communicated through both EHR and clinical processes that are embedded within routine care, including verbal and non-digital patient handover.
Summary of Interventions:
This study will evaluate the effect of a Best practice advisory (BPA) interruptive alert that is embedded within the electronic health record (EHR) used at the study site. The first BPA will ask the treating clinician whether they judge randomisation to either oral fluid restriction or no restriction is appropriate - if yes is selected, randomised allocation to one of two subsequent alerts will occur at the point of care. This intervention will be tested in silico prior to deployment to the live EHR.
Ethics:
This study protocol was approved by the London Riverside Research Ethics Committee (Ref: 22/LO/0889) and sponsored by University College London (Ref: 151938).
840 studies on the registry are indexed under Edema; 92 are open to participants now.
This study's enrollment of 23 is below the median of 52 across 608 interventional studies indexed under Edema.
Browse Edema studies →University College, London is the lead sponsor of 647 studies on the registry; 145 are open to participants now.
Of its 6 completed or terminated interventional studies of FDA-regulated products, 2 (33%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
The alert will suggest to the treating clinician to fluid restrict the patient to 1L of oral fluid per day
Behavioral: Fluid restriction
The alert will suggest to the treating clinician to continue without any oral fluid restriction
Behavioral: Free fluids
Oral fluid restriction of 1000ml per day
Continue care without any oral fluid restriction
Number of patients recruited into the trial
The number of patients in which the usual care team thought there was equipoise for oral fluid restriction
Time frame: 3 months
Difference in oral fluid intake between intervention and control arms
Difference in documented oral intake (ml)
Time frame: 48 hours after randomisation
Adherence to randomised alert recommendation
Proportion of alerts actioned with corresponding clinical documentation
Time frame: During trial recruitment window (up to day 2)
Proportion of alerts with clinical orders for nursing staff
Corresponding documentation of nursing receipt of treatment allocation
Time frame: During trial recruitment window (up to day 2)
Oral fluid intake
Documented oral fluid intake (ml)
Time frame: From date of randomisation until date of hospital discharge, assessed up to 120 days after trial start date
Net fluid balance
Documented overall fluid balance (ml)
Time frame: From date of randomisation until date of hospital discharge, assessed up to 120 days after trial start date
Weight change after randomisation
Weight (kg)
Time frame: 48 hours after randomisation
Length of stay
Number of Days
Time frame: From day of admission to day of discharge, assessed up to 120 days after trial start date
Frequency of blood test measurements of renal function
Number of times blood tests are measured
Time frame: From date of randomisation until date of hospital discharge, assessed up to 120 days after trial start date
Prescription of Diuretic medications
Dose and duration of intravenous and oral diuretics
Time frame: From date of randomisation until date of hospital discharge, assessed up to 120 days after trial start date
Daily change in creatinine
48 hours after randomisation
Time frame: From 48 hours after randomisation until date of hospital discharge, assessed up to 120 days after trial start date
Patient reported outcome measure
Visual analog scale (1-10) of wellbeing, thirst perception and breathlessness
Time frame: From date of randomisation until date of hospital discharge, assessed up to 120 days after trial start date
Plan to share: No
This study is completed, as verified in Feb 2025. You cannot join it, but the record below documents what was studied.
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