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

Study Status: Recruiting
Recruit Status: Recruiting
Study Type: Observational

Official Title: Assessment of Portal Flow Using Bedside Doppler Ultrasonography for the Detection of Portal Pulsatility as a Risk Factor for Acute Kidney Injury in Cardiac Surgery Patients

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 Summary:

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.


Sponsor: Montreal Heart Institute

Current Primary Outcome: 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) [ Time Frame: 7 days after surgery ]

The definition of acute kidney injury is based on the KDIGO guidelines


Original Primary Outcome: Same as current

Current Secondary Outcome:

  • Mortality [ Time Frame: 30 days after surgery ]
  • Duration of intensive care stay [ Time Frame: 30 days after surgery ]
  • Delirium defined as an Intensive Care Delirium Screening Checklist score of 4 or more. [ Time Frame: 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 [ Time Frame: 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.
  • Severe acute kidney injury (KDIGO stage 2 or more) defined by an increase in serum creatinine of ≥200% of baseline. [ Time Frame: 7 days after surgery ]
    The definition of acute kidney injury is based on the KDIGO guidelines
  • Discontinuous blow flow in renal interlobar vessels [ Time Frame: 3 days after surgery ]
    The presence of abnormal discontinuous blow flow in renal interlobar vessels assessed by bedside Doppler ultrasound.


Original Secondary Outcome: Same as current

Information By: Montreal Heart Institute

Dates:
Date Received: July 5, 2016
Date Started: August 2016
Date Completion:
Last Updated: August 10, 2016
Last Verified: August 2016