Clinical trial NCT02832596: Changes in Measured Plasma Volume, Glycocalyx and Atrial Natriuretic Peptide During Anaesthesia
Official title: Changes in Measured Plasma Volume, Glycocalyx and Atrial Natriuretic Peptide During Anaesthesia, a Randomised Clinical Trial
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Blood Pressure
Anesthesia
Keywords: Anesthesia
Blood pressure
Plasma Volume
Vasopressor agents
Coronary artery bypass
Glycocalyx
ANP
Coagulation
Lead sponsor: Sahlgrenska University Hospital
Sponsor class: OTHER
First posted: 2016-07-14
Enrollment: 24
Sex: ALL
Minimum age (years): 40
Maximum age (years): 90
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: BASIC_SCIENCE

Brief summary: The arterial blood pressure is thought to affect the ratio between filtration and reabsorption of fluids in the circulating blood volume and thereby the plasma volume. During induction of anesthesia blood pressure, hemoglobin level and hematocrits decreases and the plasma volume increases. The aim of the study is to evaluate weather a maintained blood pressure with norepinephrine during anesthesia induction reduces the increase in 125 iodine-labeled human serum albumine (125I-HSA) measured plasma volume.

Detailed description: 24 patients scheduled for coronary artery bypass surgery will be included and randomized to receive either norepinephrine in the dose needed to maintain pre-anesthesia blood pressure or to a control group and receive norepinephrine only if mean arterial pressure decreases below 60 mmHg. Equal anesthesia in both groups will be monitored. No fluids will be infused.

Changes in vascular resistance and cardiac output will be measured with thermodilution and changes in plasma volume will be measured with 125I-HSA.

Endothelial cell function will be evaluated by measuring leakage of 125I-HSA and the plasma concentration of endothelial cell markers. Hormonal effects will be evaluated by measuring the plasma concentration of atrial natriuretic peptide (ANP). Shedding of glycocalyx will be evaluated by measuring heparan sulphate. The level of fibrinogen and platelet function will be evaluated by thromboelastography/multiplate.

Eligibility criteria: Inclusion Criteria:

* Elective coronary artery surgery patients

Exclusion Criteria:

* Age under 40 years
* Untreated hypertension
* A reduced left ventricular systolic ejection fraction of 45% or less
* Diabetes mellitus
* Former stroke and/or a known carotid artery stenosis

Primary outcomes:
measure: The change of plasma volume measured by 125I-HSA before anesthesia induction until 50 minutes after anesthesia induction.
timeFrame: 50 minutes from anesthesia induction
Secondary outcomes:
measure: Difference in 125I-HSA leakage
timeFrame: 50 minutes from anesthesia induction
measure: ANP, heparan sulphate, thrombomodulin, fibrinogen, ROTEM
timeFrame: 50 minutes from anesthesia induction
Other outcomes:
Locations:
city: Gothenburg
country: Sweden
facility: Sahlgrenska University Hospital
Study officials:
affiliation: Sahlgrenska University Hospital
name: Andreas Nygren, MD PHD
role: PRINCIPAL_INVESTIGATOR
References: