Differential Regulation of RAAS-axis in Patients Undergoing Cardiac Surgery (RAAS-HLM)

Differences in Plasma Concentration of RAAS-axis Hormones in Patients Undergoing Cardiac Surgery With or Without Cardiopulmonary Bypass

This study investigates the question of whether there are differences in the plasma concentration of hormones of the RAAS-axis between patients undergoing on-pump cardiac surgery and those receiving off-pump surgery

Study Overview

• Status: Recruiting
• Conditions: Vasoplegia; Vasoplegic Shock
• Intervention / Treatment: Procedure: on-pump surgery; Procedure: off-pump surgery

Detailed Description

In patients undergoing cardiac surgery, the occurrence of vasoplegia or vasoplegic shock is a common and sometimes very severe complication. Although there are multiple factors that may affect the incidence and severity of vasoplegia, it remains unclear which role the use of cardiopulmonary bypass may play in the pathogenesis of this complication. The heart normally pumps blood through the lungs where the blood primarily gets oxygenated. However, it is also known that pulmonary blood flow is also essential for the activation of various hormones, some of which are central to the regulation of vascular tension and blood pressure. If the pulmonary circulation is bypassed, as is the case in on-pump cardiac surgery, it is likely that the resulting differential activity of hormones may cause or contribute to the incidence of vasoplegia. This study aims to show whether cardiopulmonary bypass leads to the differential regulation of hormones of the renin-angiotensin-aldosterone-system which could explain why some patients suffer from vasoplegia or vasoplegic shock following such procedures.

• Study Type: Observational
• Enrollment (Estimated): 40

Contacts and Locations

• Study Contact: Name: Alexander Zarbock, MD; Phone Number: +492518347255; Email: aki@anit.uni-muenster.de

Study Locations

• Germany
  • Münster, Germany, 48149
    • Recruiting
    • University Hospital Münster; Department of Anesthesiology, Intensive Care Medicine and Pain Medicine
    • Contact: Alexander Zarbock, MD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

University Hospital

Description

Inclusion Criteria:

1. adult patients undergoing on- or off-pump coronary artery bypass graft surgery
2. written informed consent

Exclusion Criteria:

1. emergency surgery in the context of acute coronary syndrome
2. ACE-inhibitor or Angiotensin 1 (AT1)-receptor-blocker intake that was not paused on the day of surgery
3. Chronic kidney disease with estimated glomerular filtration rate (eGFR)<30ml/min/1.73m²
4. Severe structural lung disease (asbestosis, silicosis, severe sarcoidosis, tuberculosis, severe emphysema, chronic obstructive pulmonary disease (COPD) Gold 3-4, lung fibrosis)
5. Chronic pulmonary hypertension
6. Pregnancy or breastfeeding
7. Persons with any kind of dependency on the investigator or employed by the institution responsible or investigator
8. Persons held in an institution by legal or official order

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
on-pump coronary artery bypass graft surgery; Due to the observational design of the study, no study-specific interventions are performed. Except for the above mentioned laboratory analyses, the treatment of the patients is completely guided by the responsible ICU physicians. Study participation does not influence the determination of surgical procedure (on- vs off-pump).	Procedure: on-pump surgery; the surgery will be performed "on-pump"
off-pump coronary artery bypass graft surgery; Due to the observational design of the study, no study-specific interventions are performed. Except for the above mentioned laboratory analyses, the treatment of the patients is completely guided by the responsible ICU physicians. Study participation does not influence the determination of surgical procedure (on- vs off-pump).	Procedure: off-pump surgery; the surgery will be performed "off-pump"

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Differences in plasma concentration of Angiotensinogen	between induction of anesthesia and immediately after surgical intervention
Differences in plasma concentration of Renin	between induction of anesthesia and immediately after surgical intervention
Differences in plasma concentration of Angiotensin I	between induction of anesthesia and immediately after surgical intervention
Differences in plasma concentration of Angiotensin converting enzyme (ACE)	between induction of anesthesia and immediately after surgical intervention
Differences in plasma concentration of Angiotensin II	between induction of anesthesia and immediately after surgical intervention
Differences in plasma concentration of Aldosterone	between induction of anesthesia and immediately after surgical intervention

Secondary Outcome Measures

Outcome Measure	Time Frame
Differences in plasma concentration of Angiotensin 1-9	between induction of anesthesia and immediately after surgical intervention
Differences in plasma concentration of Angiotensin 2-7	between induction of anesthesia and immediately after surgical intervention
Differences in plasma concentration of Dipeptidyl-peptidase 3 (DPP3)	between induction of anesthesia and immediately after surgical intervention
Incidence of vasoplegia	within 12 hours post surgery
Cumulative dose of vasopressors	within 12 hours post surgery

Collaborators and Investigators

• Sponsor: Universität Münster
• Investigators: Study Chair: Alexander Zarbock, MD, University Hospital Muenster, Dept. of Anesthesiology, Intensive Care Therapy and Pain Medicine

Study record dates

Study Major Dates

• Study Start (Actual): August 24, 2023
• Primary Completion (Estimated): November 1, 2024
• Study Completion (Estimated): February 1, 2025

Study Registration Dates

• First Submitted: January 19, 2023
• First Submitted That Met QC Criteria: April 25, 2023
• First Posted (Actual): April 27, 2023

Study Record Updates

• Last Update Posted (Estimated): December 20, 2023
• Last Update Submitted That Met QC Criteria: December 14, 2023
• Last Verified: December 1, 2023

More Information

Terms related to this study

• Keywords: cardiac surgery; cardiopulmonary bypass; vasoplegia; vasoplegic shock
• Additional Relevant MeSH Terms: Pathologic Processes; Cardiovascular Diseases; Vascular Diseases; Postoperative Complications; Vasoplegia
• Other Study ID Numbers: AnIt22-08

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: No
• Studies a U.S. FDA-regulated device product: No