A Comparison of Renal Perfusion in Thoracoabdominal Aortic Aneurysm (TAAA) Repair

May 9, 2023 updated by: Scott Lemaire, Baylor College of Medicine

A Comparison of Cold Blood Versus Cold Crystalloid Renal Perfusion for Prevention of Acute Renal Failure Following Thoracoabdominal Aortic Aneurysm Repair: A Randomized Study

The purpose of this randomized trial was to determine whether renal perfusion with cold blood provides better protection against renal ischemia than perfusion with cold crystalloid in patients undergoing TAAA repair with left heart bypass.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

Despite improvements in surgical techniques and postoperative care, renal dysfunction has consistently remained a significant and potentially lethal complication after thoracoabdominal aortic aneurysm (TAAA) repair. In an attempt to alleviate postoperative renal failure and its associated mortality, several techniques and intraoperative strategies have been used including: intraoperative administration of diuretics, steroids, or prostaglandins; minimization of ischemic times; renal hypothermia with cold crystallid solutions; selective warm (normothermic) blood perfusion as part of a left heart bypass (LHB) system; and hemodilution. However, despite the use of adjuvant techniques, the incidence of renal failure after TAAA repair still ranges from 3% to 27%. One of the techniques mentioned above involves cold crystalloid renal artery perfusion. This method aims to reduce metabolic needs of the renal system by inducing local hypothermia. Because oxygen consumption decreases 7% for each degree Celsius that temperature is reduced, the metabolic needs of tubular cells are reduced by almost 50% at 30 degrees Celsius. After the aorta is clamped and opened, the renal arteries are perfused with lactated Ringers solution (LR) that has been cooled to 4 degrees Celsius utilizing a roller pump to transport the LR through an appropriately cooled ice bath. This decreases the temperature of the kidneys to an average of 20 degrees Celsius. The volume of LR required to achieve this temperature ranges from 600 to 1800 ml. Renal cooling has been shown to preserve renal tissue as long as warm ischemic time is kept to a minimum. We recently compared renal artery cold crystalloid perfusion with normothermic blood perfusion in a randomized clinical trial involving 30 patients and discovered via multivariable analysis that cold LR was protective against acute postoperative renal dysfunction. In this study, we found that 62.5% of patients receiving normothermic blood perfusion developed acute postoperative renal dysfunction versus 21.4% in the cold LR group (p = 0.03). One method of renal protection not often used involves selective cold blood perfusion of the renal arteries. This technique also aims to reduce renal ischemic time during aortic cross-clamping and improve oxygenation to renal tissues; thereby, preventing reperfusion injury and organ dysfunction often associated with this operation. During aneurysm repair, left atrio-distal aortic bypass is performed using a centrifugal pump. Tubing connected to the distal end of this circuit passes through a container of ice allowing the perfusion of both renal arteries with cold blood. The flow rates into the renal arteries range from 100 to 450 ml/min. The celiac axis and superior mesenteric artery remain individually perfused in the standard fashion using normothermic blood. The best method of achieving renal protection remains unclear. Currently, normothermic blood and cold LR remain the two most commonly used methods of renal artery perfusion during TAAA repair. This randomized trial compared the effectiveness of two forms of renal artery perfusion, cold LR versus cold blood, to identify which method is more beneficial in the prevention of postoperative renal dysfunction.

Study Type

Interventional

Enrollment (Actual)

172

Phase

  • Not Applicable

Contacts and Locations

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

Study Locations

  • United States
    • Texas
      • Houston, Texas, United States, 77030
        • Baylor College of Medicine

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

Description

Inclusion Criteria:

  • age equal to or greater than 18
  • planned extent II or III thoracoabdominal aortic aneurysm repair
  • planned left heart bypass
  • patient consent obtained

Exclusion Criteria:

  • impaired left ventricular function
  • impaired renal function
  • prior thoracoabdominal aortic aneurysm repair
  • pseudoaneurysm
  • pre-existing liver disease
  • free aortic aneurysm rupture
  • inability to measure renal temperature
  • extent I or IV thoracoabdominal aortic aneurysm repair

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: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Single

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: 1
Cold blood renal perfusion
Procedure: Cold blood renal perfusion
Both kidneys receive intermitent perfusion with cold (4 degrees C) autologous blood during thoracoabdominal aortic aneurysm repair.
Active Comparator: 2
Cold crystalloid renal perfusion
Procedure: Cold crystalloid renal perfusion
Both kidneys receive intermittent perfusion with cold (4 degrees C) lactated Ringer's solution during thoracoabdominal aortic aneurysm repair. This is the standard renal perfusion technique in our practice.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Renal dysfunction
Time Frame: 10 postoperative days
10 postoperative days

Secondary Outcome Measures

Outcome Measure
Time Frame
Renal injury (increase in urinary biomarkers)
Time Frame: 7 postoperative days
7 postoperative days

Collaborators and Investigators

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

Sponsor

Baylor College of Medicine

Collaborators

Texas Heart Institute
Gillson-Longenbaugh Foundation

Investigators

  • Principal Investigator: Scott A. LeMaire, MD, Baylor College of Medicine

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.

General Publications

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

January 1, 2002

Primary Completion (Actual)

December 1, 2006

Study Completion (Actual)

December 1, 2006

Study Registration Dates

First Submitted

June 3, 2008

First Submitted That Met QC Criteria

June 4, 2008

First Posted (Estimate)

June 5, 2008

Study Record Updates

Last Update Posted (Actual)

May 10, 2023

Last Update Submitted That Met QC Criteria

May 9, 2023

Last Verified

May 1, 2023

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • H-9764

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

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.

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