Portal Flow Pulsatility as a Risk Factor for Acute Kidney Injury After Cardiac Surgery

Completed

• Conditions: Acute Kidney Injury; Postoperative Complications; C.Surgical Procedure; Cardiac; Cardio-Renal Syndrome; Right-Sided Heart Failure
• Interventions: Procedure: Cardiac surgery

• Registration Number: NCT02831907
• Lead Sponsor: Montreal Heart Institute

Brief Summary

The purpose of this study is to evaluate the possible association between portal vein flow pulsatility and acute kidney injury after cardiac surgery. Participants will undergo assessment of portal vein flow and intra-renal blood flow using bedside Doppler ultrasound before surgery and daily for three days after cardiac surgery.

Detailed Description

Acute kidney injury is a frequent complication after cardiac surgery. Venous congestion from right ventricular dysfunction and fluid overload can impair kidney perfusion resulting in the cardio-renal syndrome.

An increase in the variation of blood flow velocity in the portal vein during the cardiac cycle called portal pulsatility is a sign of congestive heart failure. Portal pulsatility occurs when increased central venous pressure results liver venous congestion. The presence of abnormal portal pulsatility could be used as a marker of venous congestions in other organs such as the kidneys. Discontinuous intra-renal vein flow is a risk factor for death or re-hospitalization in heart failure patients and could be seen in patients with portal pulsatility.

Study Timeline

• Study First Submitted: 2016-07-05
• Study First Submitted QC: 2016-07-11
• Study First Posted: 2016-07-13
• Study Start: 2016-08
• Primary Completion: 2017-07-31
• Study Completion: 2017-07-31
• Status Verified: 2017-08
• Last Update Submitted: 2017-08-28
• Last Update Posted: 2017-08-30

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 146

Inclusion Criteria

• 18 years and older.
• Undergoing cardiac surgery with the use of cardiopulmonary bypass
• Able to provide consent.

Exclusion Criteria

• Chronic renal replacement therapy before the procedure.
• Chronic kidney disease stage 5 defined as a estimated glomerular filtration rate by the MDRD equation (eGFR-MDRD) of 15 mL/min/1,73m2 or less.
• Critical pre-operative state defined as aborted sudden death, preoperative cardiac massage, preoperative ventilation before anaesthetic room, preoperative inotropes or intra-aortic counterpulsation balloon.
• Patients previously diagnosed with a condition interfering with Doppler evaluation of the portal system: Portal vein thrombosis, Cirrhosis.
• Patients with documented AKI before surgery.
• Confirmed or suspected pregnancy.
• Kidney transplant recipients.

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Cardiac surgery patients	Cardiac surgery	Adult patients having a cardiac surgery at the Montreal Heart Institute

Primary Outcome Measures

Name	Time	Method
Acute kidney injury defined by an increase in serum creatinine of ≥150% of baseline or an elevation of 0.3 mg/dL or more within a contiguous period of 48 hours. (KDIGO criteria)	7 days after surgery	The definition of acute kidney injury is based on the KDIGO guidelines

Secondary Outcome Measures

Name	Time	Method
Mortality	30 days after surgery
Severe acute kidney injury (KDIGO stage 2 or more) defined by an increase in serum creatinine of ≥200% of baseline.	7 days after surgery	The definition of acute kidney injury is based on the KDIGO guidelines
Duration of intensive care stay	30 days after surgery
Discontinuous blow flow in renal interlobar vessels	3 days after surgery	The presence of abnormal discontinuous blow flow in renal interlobar vessels assessed by bedside Doppler ultrasound.
Delirium defined as an Intensive Care Delirium Screening Checklist score of 4 or more.	7 days after surgery	Intensive Care Delirium Screening Checklist is a validated tool for the screening of delirium in the intensive care unit.
Composite endpoint of persistent organ dysfunction (POD) plus death at day 3 and 7	3 days and 7 days after surgery	Persistent organ dysfunction (POD) plus death is a validated outcome measure in cardiac surgery patients. It is defined as one of the following: mechanical ventilation without breaks for a period of more than 48 hours or vasopressor therapy (ongoing need for vasopressor agents such as norepinephrine, epinephrine, vasopressin, dopamine 45 μg/ kg/min, or phenylephrine 450 μg/min for more than 2 hours in a given day); or mechanical circulatory support (ongoing need for mechanical devices such as extracorporeal membrane oxygenation or intra-aortic counterpulsation balloon pump) or continuous renal replacement therapy or new intermittent hemodialysis; or death.

Trial Locations

Locations (1)

Montreal Heart Institute; 🇨🇦 Montreal, Quebec, Canada