Assessment of the Hemodynamic Effect of Hydroxocabalamin in Refractory Vasodilatory Shock

Study Overview
=================
Brief Summary
-----------------
Through clinical cases or retrospective work with small sample size, some authors have observed an improvement in hemodynamic parameters, with a reduction or even withdrawal of norepinephrine after administration of a single dose of hydroxocobolamin (HCB) in refractory vasoplegic shock (cardiac surgery, liver transplantation and septic shock). HCB produces beneficial alterations in NO metabolism and may be suitable in vasoplegic syndrome. In addition, HCB seems to be involved in the elimination of hydrogen sulfide which also has an endogenous vasodilator function in the vascular endothelium. By these different actions it would cause vasoconstriction in vascular smooth muscle cells. Previous reports demonstrate that HCB was useful for refractory vasoplegic syndrome. The investigators will conduct a retrospective data collection of patients who was given intravenous HCB for refractory vasoplegic shock since January 2019.

Detailed Description
-----------------
Vasoplegic shock is defined by arterial hypotension, a high cardiac output with a normal or high cardiac index, collapsed systemic vascular resistance (SVR) and high dose of norepinephrine in the absence of hypovolaemia. The drop in secondary organ perfusion pressure ultimately leads to multiple organ failure and death. Through clinical cases or retrospective work with small sample size, some authors have observed an improvement in hemodynamic parameters, with a reduction or even withdrawal of norepinephrine after administration of a single dose of hydroxocobolamin (HCB) in refractory vasoplegic shock (cardiac surgery, liver transplantation and septic shock). HCB produces beneficial alterations in NO metabolism and may be suitable in vasoplegic syndrome. In addition, HCB seems to be involved in the elimination of hydrogen sulfide which also has an endogenous vasodilator function in the vascular endothelium. By these different actions it would cause vasoconstriction in vascular smooth muscle cells. Previous reports demonstrate that HCB was useful for refractory vasoplegic syndrome. The investigators will conduct a retrospective data collection of patients who was given intravenous HCB for refractory vasoplegic shock since January 2019.

Official Title
-----------------
Assessment of the Hemodynamic Effect of Hydroxocabalamin in Refractory Vasodilatory Shock

Conditions
-----------------
Hemodynamics, Vasoplegia, Intensive Care Unit, Shock

Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: All SVR patients over 18 years of age who had received a dose of HCB since January 1 2019 will be included. Exclusion Criteria: Patients who received treatment for another indication were not included.

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| responders to treatment<br>A patient will be defined as a responder to hydroxocobolamin infusion if there is an increase of more than 20% in Average blood pressure, relative to the pre-treatment value, for at least 15 minutes within one hour of treatment administration. | |
| non-responders to treatment<br>A patient will be defined as a non-responder to hydroxocobolamin infusion if there is not an increase of more than 20% in Average blood pressure, relative to the pre-treatment value, for at least 15 minutes within one hour of treatment administration. | |

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of patients responding to treatment with HCB | A patient will be defined as a responder to hydroxocobalamin infusion if there is an increase of more than 20% in average blood pressure, relative to the pre-treatment value, for at least 15 minutes within one hour of treatment administration. | 1 hour | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The change in average blood pressure over time in responder patients | Blood pressure is measured in units of millimeters of mercury (mmHg). | one hour | 
| The change in average blood pressure over time in non-responder patients | Blood pressure is measured in units of millimeters of mercury (mmHg). | one hour | 
| The change in doses of NAd (mg/h) in responder patients |  | one hour | 
| The change in doses of NAd (mg/h) in non-responder patients |  | one hour | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
vasoplegia, hydroxocobalamin, hemodynamics, intensive care unit, shock