Effects of Prolonged Delivery of Nitric Oxide Gas on Plasma Reduction-Oxidation Reactions in Cardiac Surgical Patients

November 9, 2022 updated by: Lorenzo Berra, MD, Massachusetts General Hospital

This study is an ancillary (add-on) study to the clinical trial entitled "Effect of Nitric Oxide in Cardiac Surgery Patients With Endothelial Dysfunction", which has Clinical Trials.gov identifier NCT02836899. NCT02836899 trial randomizes cardiac surgical patients to receive either Nitric Oxide (NO) or a placebo during and after cardiac surgery.

This ancillary study aims to assess the effects of Nitric Oxide on plasma reduction-oxidation reactions of patients undergoing cardiac surgery requiring prolonged cardiopulmonary bypass.

Study Overview

Detailed Description

The endothelial dysfunction is a pathologic process characterized by impaired endothelial nitric oxide (NO) signaling and metabolism leading to decreased vascular response to vasodilation. Cardiac surgical patients affected by multiple cardiovascular risk factors (e.g., hypertension, diabetes, dyslipidemia) commonly present with endothelial dysfunction due to a chronic unbalance of the redox state caused by an increased oxidative stress. Moreover, the use of cardiopulmonary bypass, the hemolysis, the ischemia and the inflammation associated with the surgery magnifies the oxidative stress, which has been shown to contribute to post-operative complications. In order to decrease oxidative stress, several antioxidant drugs and vitamins have been trialed with marginal health benefits.

Recently, different research groups reported that NO delivered during cardiac surgery improved outcomes both in children and adults. Nitric oxide decreased the incidence and the severity of postoperative acute kidney injury, the extension of infarction size, the duration of mechanical ventilation, the length of stay and the use of rescue therapies as postoperative venous-arterial extra-corporeal membrane oxygenation.

The exogenous administration of NO has been shown to prevent the scavenging of endogenous NO by inactivating the highly oxidative-reactive ferrous plasma oxy-hemoglobin to ferric met-hemoglobin. Our group is conducting a randomized controlled trial at Massachusetts General Hospital (Boston, USA) in patients with signs and symptoms of endothelial dysfunction, undergoing cardiac surgery requiring prolonged cardiopulmonary bypass and randomized to receive NO or placebo. However, the mechanisms underlying the effects of NO admistration on plasmatic redox equilibrium have still to be determined. The aim of this ancillary study is (I) to determine the changes of redox state in the plasma of surgical patients receiving either 80 ppm of NO (study group) or Nitrogen (placebo group). (II) To evaluate whether the degree of change in redox state is associated to postoperative complication.

Study Type

Interventional

Enrollment (Anticipated)

100

Phase

  • Phase 2

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Study Locations

    • Hampshire
      • Southampton, Hampshire, United Kingdom, SO16 6YD
        • Active, not recruiting
        • MP 825 Southampton General Hospita
    • Massachusetts
      • Boston, Massachusetts, United States, 02114
        • Recruiting
        • Massachusetts General Hospital
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Eligible and randomized in the trial NCT02836899
  • Provide written informed consent
  • Age ≥ 18 years of age
  • Elective cardiac or aortic surgery with CPB >90 minutes
  • Clinical evidence of endothelial dysfunction assessed by a specifically designed questionnaire

Exclusion Criteria:

  • Estimated Glomerular Filtration Rate less than 30 ml/min/1.73 m2
  • Emergent cardiac surgery
  • Life expectancy < 1 year at the time of enrollment
  • Hemodynamic instability as defined by a systolic blood pressure <90 mmHg.
  • Mean pulmonary artery pressure ≥ 40 mm Hg and PVR > 4 Wood Units.
  • Left ventricular ejection fraction < 30% by echocardiography obtained within three months of enrollment
  • Administration of one or more Packed Red Blood Cell (PRBC) transfusions in the week prior to enrollment
  • X-ray contrast infusion less than 48 hours before surgery
  • Evidence of hemolysis from any other origin:

    a. Intravascular: i. Intrinsic RBC defects leading to hemolytic anemia (eg, enzyme deficiencies, hemoglobinopathies, membrane defects) ii. Extrinsic: liver disease, hypersplenism, infections (eg, bartonella, babesia, malaria), treatment with oxidizing exogenous agents (eg, dapsone, nitrites, aniline dyes), exposure to other hemolytic agents (eg, lead, snake and spider bites), lymphocyte leukemia, autoimmune hemolytic disorders b. Extravascular: Infection (eg, clostridial sepsis, severe malaria), paroxysmal cold hemoglobinuria, cold agglutinin disease, paroxysmal nocturnal hemoglobinuria, iv infusion of Rho(D) immune globulin, iv infusion of hypotonic solutions

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Quadruple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Placebo Comparator: Nitrogen
Inhaled nitrogen will be administered via the cardiopulmonary bypass (CPB) machine and after CPB via the inspiratory limb of the anesthetic or ventilator circuit, and thereafter via the mechanical ventilator in the Intensive Care Unit (ICU). Test gas administration will commence at the onset of CPB and last for 24 hours.
See arm description
Other Names:
  • N2
Blood samples will be collected over four time-points: (I) baseline (before surgery) (II) end of the surgery, (III) end of 24 hours of gas delivery and (IV) 24 hours from the gas suspension.
Experimental: Nitric Oxide
Inhaled nitric oxide (iNO) will be administered via the cardiopulmonary bypass (CPB) machine and after CPB via the inspiratory limb of the anesthetic or ventilator circuit, and thereafter via the mechanical ventilator in the ICU. Test gas administration will commence at the onset of CPB and last for 24 hours. At the end of 24 hours, inhaled nitric oxide (iNO) will be weaned and discontinued.
Blood samples will be collected over four time-points: (I) baseline (before surgery) (II) end of the surgery, (III) end of 24 hours of gas delivery and (IV) 24 hours from the gas suspension.
See arm description
Other Names:
  • iNO

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Changes in the concentration of glutathione/glutathione disulfide (GSH/GSSG) and the cysteine/ cysteine disulfide (Cys/CysSS) couples in the plasma after cardiac surgery.
Time Frame: Plasma will be sampled before the cardiac surgery and during the first 48 hours from surgery
The investigators will measure the changes in plasma concentration of GSH, GSSG, Cys, CysSS, of subjects undergoing cardiac surgery with prolonged cardiopulmonary bypass, using ultrahigh-performance liquid chromatography in combination with electrospray-ionization tandem mass spectrometry. The concentration will be expressed in microMoles.
Plasma will be sampled before the cardiac surgery and during the first 48 hours from surgery
Changes in the electrical potential of glutathione/glutathione disulfide (GSH/GSSG) and the cysteine/ cysteine disulfide (Cys/CysSS) couples in the plasma after cardiac surgery.
Time Frame: Plasma will be sampled before the cardiac surgery and during the first 48 hours from surgery
The investigators will compare the changes of plasma redox state from baseline of patients receiving either 80 ppm of nitric oxide (study group) or nitrogen (placebo group), during cardiac surgery. The redox state will be assessed by measuring the electrical potential of GSH/GSSG and the Cys/CysSS couples in the plasma, using Nerst's equation. The electrical potential will be express in milliVolt.
Plasma will be sampled before the cardiac surgery and during the first 48 hours from surgery

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Changes of concentration in plasma and red blood cells of nitric oxide metabolites after cardiac surgery.
Time Frame: Plasma will be sampled before the cardiac surgery and after the first 48 hours from surgery
The investigators will describe the trends in plasma and red blood cells of nitric oxide (NO) metabolites after the surgery. Nitric oxide (NO) metabolites concentrations will be measured using chemiluminescence. The concentrations will be expressed in microMoles.
Plasma will be sampled before the cardiac surgery and after the first 48 hours from surgery

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

July 25, 2019

Primary Completion (Anticipated)

February 28, 2024

Study Completion (Anticipated)

July 31, 2024

Study Registration Dates

First Submitted

July 10, 2019

First Submitted That Met QC Criteria

July 14, 2019

First Posted (Actual)

July 16, 2019

Study Record Updates

Last Update Posted (Actual)

November 10, 2022

Last Update Submitted That Met QC Criteria

November 9, 2022

Last Verified

November 1, 2022

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

No

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Cardiovascular Diseases

Clinical Trials on Nitrogen Gas for Inhalation

3
Subscribe