Hemodynamic support Prospective multicenter observational study of patients in shock treated with vasopressin: Protocol of the VASOPRESIN with vasopressin: VASOPRES Registry study protocol.

Background: In cases of arterial hypotension and/or hypoperfusion that do not respond to fluid therapy, the administration of intravenous catecholamines, especially norepinephrine, is usually the treatment of choice. However, prolonged exposure to high doses of norepinephrine increases mortality, as well as the possibility of arrhythmias, organ damage, and tissue ischemia. An early multimodal vasopressor strategy, which involves adding vasopressin (a drug with a mechanism of action different from catecholamines) to low-dose norepinephrine, could improve the safety profile.

Objective: The main objective is to characterise the routine clinical practice of vasopressin (VASOPRES) use in the context of shock, collecting clinical, analytical and echocardiographic data.

Methods: The VASOPRES Registry is a prospective multicentre observational study, in which critical care anaesthesia units from all over Spain will participate, collecting data on patients over 18 years of age in whom treatment with vasopressin is initiated, regardless of the type of shock they present. The duration of the study is estimated at 24 months, starting from its approval by the Clinical Research Ethics Committee (CEIm).

Results: Data collection started in July 2024 and is expected to end in July 2026. The Vasopres registry has already been approved by the Clinical Research Ethics Committee of the Hospital Universitario de La Princesa, Madrid (registration number 5596) in May 2024. The study is registered in ClinicalTrials.gov under the number NCT06422975 and in the Spanish Clinical Trials Register (REec) through the GESTO platform (Observational studys with authorized medicines) under the identification number 0083-2024-OBS. The results will be published in specialised journals and presented at conferences and congresses.

Conclusions: The Vasopres Registry may provide insight into the uncertainties that still exist about the use of AVP as well as its use in routine clinical practice in various types of shock. Furthermore, it is also hoped that the results of this study will identify potential areas for improvement where more targeted research is needed.