Near Infrared Spectroscopy for the Detection of Acute Kidney Injury in Children Following Cardiac Surgery
Condition: Acute Kidney Injury; Heart; Dysfunction Postoperative, Cardiac Surgery; Children
MeSH terms: Acute Kidney Injury; Wounds and Injuries
Study type: Observational

Summary: 
      One in a hundred children is born with a heart defect. Some children require heart surgery
      within the first few days of life, while others can wait until they are older. A complication
      of open-heart surgery is low blood flow due to the heart-lung machine that can cause sudden
      loss of kidney function known as acute kidney injury (AKI). AKI causes complications that can
      increase hospital length of stay and increase risk of death. Current ways to identify AKI are
      not able to it until 2 or 3 days after it has occurred. Because of this, there is not a
      specific treatment for AKI. If the investigators diagnose AKI early, they might be able to
      treat it and improve outcomes in children. NIRS is a skin monitor that can detect low blood
      flow to the kidney and might help diagnose AKI when it occurs in the operating room. The use
      of NIRS to diagnose AKI early is the focus of this study.
    

Detailed description: 
      Near infrared spectroscopy (NIRS) is a noninvasive tool used for continuous monitoring of
      regional tissue oxyhemoglobin saturation. Sensors are placed on the head and abdomen or flank
      and use light to measure the percent oxygen levels in tissues. Head NIRS has been correlated
      with oxygen levels of the blood returning from the brain, and an abrupt decline in
      post-operative cardiac patients has been shown in retrospective studies to predict an
      impending event such as cardiac arrest. Animal studies have demonstrated that somatic NIRS
      monitoring is able to detect flow-induced changes in regional oxygen levels of the kidney and
      gut directly under the sensor. Unlike cerebral NIRS monitoring, there is no data regarding
      the clinical utility of NIRS over the abdomen and flank in predicting outcomes. Children are
      at risk of decreased organ perfusion following cardiac surgery, and is a phenomenon termed
      low cardiac output syndrome (LCOS). It occurs in approximately 25% of neonates and young
      children following cardiac surgery. The effects of LCOS on end organ function, specifically
      the kidney may result in acute kidney injury, thereby increasing morbidity and mortality. The
      incidence of acute kidney injury (AKI) following cardiac surgery is reported as high as 40%.
      The use of NIRS in the operating room to detect AKI in pediatric patients undergoing cardiac
      surgery is the focus of this proposal Specific Aim 1: Determine if a reduction in renal NIRS
      intra-operatively identifies patients with AKI Hypothesis: Reduced intra-operative renal NIRS
      will precede the diagnosis of acute kidney injury by an increase in serum creatinine within 1
      to 3 days post-cardiopulmonary bypass Specific Aim 2: Determine if a reduction in renal NIRS
      intra-operatively correlates with increases in emerging biomarkers of AKI.

      Hypothesis: Reduced intra-operative renal NIRS will precede the development if AKI as
      detected by neutrophil gelatinase-associated lipocalin, IL-6 and IL-18 by at least 2 hours.
    

Observational model: Case-Control
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        All children undergoing cardiac surgery with the use of cardiopulmonary bypass at our
        institution.
      
Biospecimen description: 
      Serum, Urine
    
Keywords: Near Infrared Spectroscopy (NIRS); Acute kidney injury (AKI)