Effect of Protein Supplementation and Fluid Restriction on Plasma Sodium Levels in Patients Undergoing Pituitary Surgery
TREASURE-PIT
1 other identifier
interventional
282
1 country
1
Brief Summary
The investigators are conducting this study to investigate new preventive measures for patients with low sodium levels (hyponatremia), which can occur after surgery on the pituitary gland. This hyponatremia is often caused by the syndrome of inappropriate antidiuresis (SIAD). SIAD occurs when the pituitary gland secretes too much antidiuretic hormone. The antidiuretic hormone causes the kidneys to absorb more water. This dilutes the sodium in the blood and leads to hyponatremia. Low sodium levels are particularly common after pituitary surgery, as the procedure on the pituitary gland can lead to increased reactive secretion of antidiuretic hormone. At present, apart from educating patients about the symptoms of hyponatremia, there are no established standard measures for prevention after pituitary surgery. If hyponatremia is present, it is currently treated primarily by fluid restriction, which is not always pleasant or easy to adhere to. With this study, the investigators want to investigate whether protein supplementation or fluid restriction between day 4 and day 9 after surgery can serve as a preventive measure to stabilize sodium levels after pituitary surgery and improve the quality of life of patients.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P75+ for not_applicable
Started Jan 2026
Typical duration for not_applicable
1 active site
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
November 14, 2025
CompletedFirst Posted
Study publicly available on registry
December 9, 2025
CompletedStudy Start
First participant enrolled
January 20, 2026
CompletedPrimary Completion
Last participant's last visit for primary outcome
October 1, 2028
ExpectedStudy Completion
Last participant's last visit for all outcomes
October 1, 2028
February 3, 2026
February 1, 2026
2.7 years
November 14, 2025
February 2, 2026
Conditions
Keywords
Outcome Measures
Primary Outcomes (1)
Odds ratio of treatment failure (intervention compared to standard of care)
The primary objective is to evaluate the effectiveness of fluid restriction (Treatment A), and dietary protein supplementation (Treatment B) compared to the current standard care with no specific intervention and no fluid management guidance (Treatment C) in preventing treatment failure, defined at day 9 as a decrease in plasma sodium by at least 4 mmol/lL from baseline, and hyponatremia (plasma sodium \<135mmol/L) or a decrease of at least 1 point in the MoCa score compared to baseline.
3 days post-surgery (time of randomization), and day 9 post-surgery.
Study Arms (3)
Limited fluid intake
EXPERIMENTALPatients will limit their total daily fluid intake
Additional protein
EXPERIMENTALPatients will consume additional protein daily
No instructions
ACTIVE COMPARATORPatients will not receive specific instructions.
Interventions
Patients will limit their total daily fluid intake to a maximum of 1000 ml, including any liquids of their choice, such as water, milk, or juice.
Patients will not receive specific instructions on protein supplementation or fluid restriction. They will follow standard post-operative care and drink or eat freely based on natural appetite and thirst.
Patients will consume an additional 80 grams of protein daily through two 150 ml protein drinks (40 grams of protein each, MOLTEIN PURE Drink, OMANDA) in various flavors. They can distribute the drinks throughout the day and drink other fluids freely based on thirst.
Eligibility Criteria
You may qualify if:
- Adult patients (aged 18 or older) undergoing trans-sphenoidal or trans-cranial surgery for sellar / suprasellar pathology
- No pre-existing AVP-deficiency and SIAD or other causes of hyponatremia
You may not qualify if:
- AVP deficiency diagnosed before surgery based on established criteria
- Other type of neurosurgery / intracranial pathology / pre-existing spontaneous CSF -rhinorrhea
- Traumatic brain injury or intracranial hemorrhage
- Systemic infection or other causes for systemic stress
- Lactose intolerance, milk protein allergy, soy allergy, nuts allergy or known hypersensitivity or allergy to one of the components of the protein supplementation
- Inborn metabolic disorders implying carbohydrate, lipid, or protein metabolism
- Severe hepatic impairment (ALAT/ASAT \>3x upper limit) or advanced symptomatic liver disease defined as past or current hepatic encephalopathy, liver cirrhosis Child C, or decompensated (bleeding, jaundice, hepatorenal syndrome)
- Reduction of eGFR \<45 mL/min/1.73m² (KDIGO G3b, G4 and G5) or end stage renal disease (dialysis)
- Recently initiated (within the last 5 days) SGLT2 inhibitors, vaptans, or oral urea therapy
- Pregnancy or breastfeeding
- Lack of capacity or other reason preventing from giving informed consent or following study procedures.
Contact the study team to confirm eligibility.
Sponsors & Collaborators
Study Sites (1)
University Hospital Basel
Basel, 4031, Switzerland
MeSH Terms
Conditions
Condition Hierarchy (Ancestors)
Study Officials
- PRINCIPAL INVESTIGATOR
Mirjam Christ-Crain, Prof. Dr. med.
University Hospital Basel, Endocrinology
Central Study Contacts
Study Design
- Study Type
- interventional
- Phase
- not applicable
- Allocation
- RANDOMIZED
- Masking
- NONE
- Purpose
- PREVENTION
- Intervention Model
- PARALLEL
- Sponsor Type
- OTHER
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
November 14, 2025
First Posted
December 9, 2025
Study Start
January 20, 2026
Primary Completion (Estimated)
October 1, 2028
Study Completion (Estimated)
October 1, 2028
Last Updated
February 3, 2026
Record last verified: 2026-02