Differential Regulation of RAAS-axis in Patients Undergoing Cardiac Surgery

Recruiting

• Conditions: Vasoplegia; Vasoplegic Shock
• Interventions: Procedure: on-pump surgery; Procedure: off-pump surgery

• Registration Number: NCT05833828
• Lead Sponsor: Universität Münster

Brief Summary

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

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 Timeline

• Study First Submitted: 2023-01-19
• Study First Submitted QC: 2023-04-25
• Study First Posted: 2023-04-27
• Study Start: 2023-08-24
• Status Verified: 2024-12
• Last Update Submitted: 2024-12-06
• Last Update Posted: 2024-12-12
• Primary Completion: 2025-05
• Study Completion: 2025-08

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 40

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 & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
on-pump coronary artery bypass graft surgery	on-pump 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).
off-pump coronary artery bypass graft surgery	off-pump 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).

Primary Outcome Measures

Name	Time	Method
Differences in plasma concentration of Renin	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 I	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 Angiotensinogen	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

Name	Time	Method
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
Differences in plasma concentration of Angiotensin 1-9	between induction of anesthesia and immediately after surgical intervention

Trial Locations

Locations (2)

Deutsches Herzzentrum der Charité; 🇩🇪 Berlin, Germany

University Hospital Münster; Department of Anesthesiology, Intensive Care Medicine and Pain Medicine; 🇩🇪 Münster, Germany