Systematic Use of DDAVP to Prevent Serum Sodium Overcorrection in Severe Hyponatremia: a Multicenter Open-label Randomized Controlled Trial (DASSOH)

Systematic Use of DDAVP to Prevent Serum Sodium Overcorrection in Severe Hyponatremia: a Multicenter Open-label Randomized Controlled Trial

Systematic Use of DDAVP to Prevent Serum Sodium Overcorrection in Severe Hyponatremia: a Multicenter Open-label Randomized Controlled Trial

Multicentre, prospective, open-label randomized controlled superiority trial with stratification on the presence of neurological symptoms at inclusion and on the presence/absence of risk factors for central pontine myelinolysis (chronic alcohol abuse, malnutrition, serum potassium < 3.0 mmol/L). Patients in ICU with severe hyponatremia defined by SNa < 115 mmol/L or SNa < 120 mmol/L in the presence of neurological symptoms (convulsions, stupor defined by a Glasgow score <12 or signs of brain herniation) and a normal or decreased extracellular fluid volume will be included. After written informed consent, they will be randomized (1:1), using a computer-generated randomization scheme of various-sized blocks, stratified by the presence of neurological symptoms at inclusion (seizures, stupor defined as Glasgow score <12 or signs of brain herniation) and on the presence/absence of risk factors for central pontine myelinolysis (chronic alcohol abuse [defined according to World Health Organization definition], malnutrition [BMI<20.5 or weight loss >5% in 3 months], serum potassium < 3.0 mmol/L), through a centralized 24-hour Internet service (CleanWEB™), to receive standard hyponatremic treatment alone or standard hyponatremic treatment and DDAVP 4 μg/ml IV, after randomisation and for a total duration of 48 hours. Since administration of DDAVP leads to an important decrease in urine output and increase in urine osmolarity which are clinically obvious very rapidly, a single or double blind trial is not appropriate. However, all investigators will be unaware of aggregate outcomes during the study and brain MRI imaging will be performed and analyzed blinded to the randomization group

Multicentre, prospective, open-label randomized controlled superiority trial with stratification on the presence of neurological symptoms at inclusion and on the presence/absence of risk factors for central pontine myelinolysis (chronic alcohol abuse, malnutrition, serum potassium < 3.0 mmol/L).

DDAVP 4µg/ml IV Additional doses may be administrated every 6h for a maximum of 48h - Standard hyponatremia treatment : Presence of neurological symptoms : sodium chloride 3% 150ml for 20 min Absence of neurological symptoms : Hyper or isotonic fluid but never hypotonic

Standard hyponatremia treatment alone : Presence of neurological symptoms : sodium chloride 3% 150ml for 20 min Absence of neurological symptoms : Hyper or isotonic fluid but never hypotonic

Posology: 4µg in 2ml IV solution Route of administration: Intravenous Duration of treatment: 48h maximum (additional doses every 6h)

Standard hyponatremia treatment alone : Presence of neurological symptoms : sodium chloride 3% 150ml for 20 min Absence of neurological symptoms : Hyper or isotonic fluid but never hypotonic

reduced occurrence of overcorrection of serum sodium concentration (SNa) in the first 48 hours after randomization

proportion of patients with SNa level overcorrection : any risk factor: SNa increase > 6 mmol/L in less than H24, or >12 mmol/L in less than H48. Without risk factor: SNa increase > 10 mmol/L in less than H24, or > 18 mmol/L in less than H48

proportion of patients with neurological symptoms at inclusion and who subsequently have a normal Glasgow Coma Scale at H6

proportion of patients with the occurrence of central pontine myelinolysis diagnosed on clinical and MRI criteria at day 15 (or earlier if clinically justified)

proportion of patients with any (pontine or extrapontine), symptomatic or not, osmotic demyelination as assessed by brain MRI at day 15 (or earlier if clinically justified)

on the percentage of patients with neurological symptoms at inclusion and reaching the initial goal of rapid partial pre-defined correction of SNa level

proportion of patients with neurological symptoms with an increase of 5.0 mmol/L or more of SNa from inclusion to H6

the occurrence of any new neurological sign in relation with hyponatremia in patients with a normal neurological exam at inclusion or on the reappearance of any neurological sign in relation with hyponatremia after inclusion

proportion of patients with seizures, stupor or sign of brain herniation appearing or reappearing after inclusion

Inclusion Criteria: Adults ( ≥18 years) Current admission in ICU Severe hyponatremia defined by SNa <120 mmol/L in the presence of neurological symptoms (seizures, stupor defined as Glasgow score < 12, or signs of brain herniation) or by SNa <115 mmol/L Normal or decreased extracellular fluid volume Exclusion Criteria: Obvious increase of extracellular fluid volume (cirrhosis with ascites, congestive heart failure, nephrotic syndrome); Previous DDAVP or hypertonic fluid administration for the current episode of severe hyponatremia SNa increased by 5 mmol or more between admission at hospital and randomisation (H0) Known contraindication to DDAVP Allergy Syndrome of inappropriate antidiuretic hormone secretion (SIADH) History of unstable angina and/or known or suspected heart failure. Willebrand disease type 2b (due to risk of thrombocytopenia) Severe previous neurologic disability (Glasgow Outcome Scale < 3) Diabetes insipidus receiving DDAVP treatment Moribund state (patient likely to die within 24h) Need for invasive mechanic ventilation Limitation of life support (comfort care applied only) at the time of screening Enrolment to another interventional study on hyponatremia care/management Pregnancy or breastfeeding Subject deprived of freedom, subject under a legal protective measure No affiliation to any health insurance system Refusal to participate to the study (patient or legal representative or family member or close relative if present)