An interventional study of Liberal Phosphate Replacement Protocol and Restrictive Phosphate Replacement Protocol in Phosphate Deficiency, Hypophosphatemia and Protocol Optimization, sponsored by Caboolture Hospital. Not yet recruiting. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-12-17.
Sponsored by Caboolture Hospital · Not applicable, Interventional, and Other
The aim of this cluster, crossover, randomised controlled trial is to compare two standard arms of treatment for the replacement of phosphate in critically ill patients.
We hypothesise that protocolised restricted phosphate replacement, compared to protocolised liberal phosphate replacement, will result in reduced administration of phosphate with similar clinical outcomes.
All eligible Intensive Care Unit (ICU) patients will be included during their admission with the selected protocol for that period as per usual practice and treatment standards.
This study looks to compare liberal and restrictive phosphate replacement protocols (each arm is a current "standard of care" already used in practice) to investigate whether restrictive phosphate replacement in critically ill patients leads to reduced phosphate administration and/or equivalent patient outcomes.
Derangements of serum phosphate concentrations are common among ICU patients; high and low levels variably associated with worse outcomes. The PROMPT trial will compare two standard arms of treatment for the replacement of phosphate in critically ill patients. Phosphate is currently replaced routinely in ICU's however there is not a standardised evidence-based guideline to effectively guide phosphate administration for ICU patients
This is a cluster, crossover, electronic medical record integrated, randomised, controlled trial. Sites (not patients) will be randomised to wither the liberal or restrictive phosphate replacement protocol for a 6-month period, followed by a 1-month washout period, before switching to the next protocol for the preceding 6-month period. The allocated phosphate replacement protocol will be updated in the electronic medical record to be followed; this process is already part of normal clinical practice.
53 studies on the registry are indexed under Hypophosphatemia; 16 are open to participants now.
This study's planned enrollment of 2,400 is above the median of 46 across 26 interventional studies indexed under Hypophosphatemia.
Browse Hypophosphatemia studies →This is the only study on the registry with Caboolture Hospital as lead sponsor.
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Exclusion Criteria:
The liberal group, a recommendation for phosphate replacement would be given if the serum phosphate concentration was 0.79 mmol/L, but not if 0.80 mmol/L.
Other: Liberal Phosphate Replacement Protocol
The restrictive protocol will recommend phosphate replacement to commence at a threshold of 0.50 mmol/L, and the liberal protocol at 0.80 mmol/L.
Other: Restrictive Phosphate Replacement Protocol
The liberal group, a recommendation for phosphate replacement would be given if the serum phosphate concentration was 0.79 mmol/L, but not if 0.80 mmol/L.
The restrictive protocol will recommend phosphate replacement to commence at a threshold of 0.50 mmol/L, and the liberal protocol at 0.80 mmol/L.
non-inferiority for days alive and free of the intensive care unit (ICU) up to 30 days (DAF-ICU-30)
The primary outcome will be assessed as non-inferiority in the number of days alive and free of ICU within 30 days from study enrolment. ICU length of stay will be used to calculate. This measure is reported on a continuous scale ranging from 0 (worst outcome: death or full ICU stay) to 30 (best outcome: alive and ICU-free for all 30 days), where higher scores indicate a better outcome. The difference between groups will be expressed as a mean difference with 95% confidence intervals.
Time frame: 30 Days post study enrolment
Phosphate usage
Quantities of intravenous and oral phosphate replaced (total and individually)
Time frame: individual arm and total quantities used over 12-month study period
Patients receiving phosphate
Proportion of patients receiving any phosphate replacement
Time frame: total proportion of patients receiving phosphate throughout 12-month study period
Hospital Length of Stay
Total time spent in hospital - hospital admission time to hospital discharge time
Time frame: hospital admission to hospital discharge throughout 12-month study period
Hospital Mortality
hospital mortality rates for all participants throughout study period
Time frame: hospital admission to hospital discharge throughout 12-month study period
cardiac rhythm disturbance
Symptomatic cardiac rhythm disturbance (cardiac arrhythmia that requires treatment with chemical or electric cardioversion)
Time frame: ICU admission to ICU discharge, throughout 12-month study period
Mechanical ventilation hours
Hours of invasive mechanical ventilation
Time frame: hospital admission to hospital discharge, throughout 12-month study period
Tracheal reintubation
Tracheal intubation requirement during admission
Time frame: hospital admission to hospital discharge, throughout 12-month study period
No study locations are listed for this record.
Plan to share: No
Start is estimated for Jan 2026; primary completion for Feb 2027, 13 months later.
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This study is not yet recruiting, as verified in Dec 2025. You cannot join it, but the record below documents what was studied.
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