NAD Supplementation to Reduce the Incidence of Cardiac Surgery Associated Acute Kidney Injury

This single-center, randomized, double-blind, placebo-controlled trial will serve as a pilot for a larger study that aims to assess the efficacy of nicotinamide in reducing ischemia-reperfusion injury and acute kidney injury (AKI) in patients undergoing cardiac surgery. A total of 20 patients will be randomized in a 1:1 ratio to receive either a one-time dose of NAM 3000 mg or a matching placebo on the morning of surgery. Safety assessments and clinical outcomes will be monitored for 2 days (> 5 half-lives) . Blood samples will be collected from patients at up to two time points: preoperatively (after insertion of an arterial line [for blood] and intraoperatively at the end of CPB. Urine samples will also be collected at two timepoints: after insertion of the foley catheter but prior to incision, and on the morning of post-operative day 1. Discarded tissue specimens will be collected from patients at two time points: initially when excised pre-bypass, and another post-bypass, depending on the tissue availability and as a regular part of the surgery. Time points will be recorded for all the collections.

Inclusion criteria

• Age ≥18 years
• Undergoing coronary artery bypass graft (CABG) and/or valve surgery with cardiopulmonary bypass (CPB) at BIDMC. Includes combination surgeries that involve CABG and/or valve plus other procedures (e.g., Maze procedure, aortic aneurysm repair).
• AKI risk score ≥6 at the time of screening

Exclusion criteria

• History of AKI in the seven days prior to surgery, defined as any of the following:

• Increase in serum creatinine ≥0.3 mg/dl in 48h
• Increase in serum creatinine ≥50% in 7d (if no value available in last 7d, use most recent value in last 3 months)
• Urine output ≤0.5 ml/kg/h x 6 consecutive hours (only assessed in patients with hourly monitoring via Foley catheter)
• Receipt of renal replacement therapy (RRT) within 7d
• Advanced chronic kidney disease (eGFR <15 ml/min/1.73m2 or end-stage kidney disease receiving RRT)
• Pregnant or breastfeeding*
• Positive COVID test in the last 10 days.
• Prisoner or institutionalized
• Existing or anticipated durable VAD

• Conflict with other studies

• Previous usage of nicotinamide supplements in the past 30 days