Clinical trial NCT04250389: Microcirculatory Effects of Methylene Blue
Official title: Microcirculatory Effects of Methylene Blue in Vasoplegic Shock After Cardiopulmonary Bypass: a Pilot Study
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Acute Circulatory Failure
Keywords: Methylene Blue
Lead sponsor: Hospices Civils de Lyon
Sponsor class: OTHER
First posted: 2020-01-31
Enrollment: 25
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: All patients receiving methylene blue for refractory vasoplegic shock (VS) in intensive care unit after Cardiopulmonary Bypass CPB. Refractory VS was defined as follow: a dose of norepinephrine \> 0.5µg/kg/min to obtain a mean arterial pressure of 65-75 mmHg with a normal or increase cardiac (\> 2 L.min-1.m-2).

Brief summary: International guidelines recommend Methylene Blue (MB) as a second-line drug in the treatment of norepinephrine refractory vasoplegic shock (VS) after Cardiopulmonary Bypass CPB. Macrocirculatory effects of MB in this setting are now well established but microcirculatory effects of MB remain unknown.

The purpose of this study is to assess the micro vascular effects of a single administration of methylene blue (1.5 mg/kg over 30 minutes) for norepinephrine-refractory VS post CPB.

Microcirculatory effect will be monitored before and one hour after MB infusion through cutaneous refill time, video microscopy measurements of the sublingual microcirculation and tissue oxygen saturation combined with vascular occlusion test (VOT).


Eligibility criteria: Inclusion Criteria:

* patients receiving methylene blue prescribed by the clinician in charge of the patient
* patient receiving a dose of norepinephrine \> 0.5µg/kg/min
* normal or increase cardiac (\> 2 L.min-1.m-2) at the time of inclusion
* vasoplegic syndrome post cardiopulmonary bypass for cardiac surgery

Exclusion Criteria:

* the need for hemodynamic intervention during the time of study (fluid resuscitation, introduction of inotropic or vasopressor support, change in inotropic support dose)
* age under 18 years

Primary outcomes:
measure: Change in tissue oxygenation (resaturation speed expressed as %/sec) during the vessel obstruction test.
timeFrame: one hour after the start of methylene blue infusion
Secondary outcomes:
measure: Video microscopy measurements of the sublingual microcirculation
timeFrame: one hour after the start of methylene blue infusion
measure: Cutaneous and gingival refill time
timeFrame: one hour after the start of methylene blue infusion
measure: Metabolic variables
timeFrame: one hour after the start of methylene blue infusion
Other outcomes:
Locations:
city: Bron
country: France
facility: Service d'anesthesie reanimation, Hôpital cardiologique Louis Pradel
Study officials:
References:
citation: Maurin C, Portran P, Schweizer R, Allaouchiche B, Junot S, Jacquet-Lagreze M, Fellahi JL. Effects of methylene blue on microcirculatory alterations following cardiac surgery: A prospective cohort study. Eur J Anaesthesiol. 2022 Apr 1;39(4):333-341. doi: 10.1097/EJA.0000000000001611.