Dr. Tanvi Khera joined the team at Beth Israel Deaconess Medical Center as a Clinical Research Fellow in July 2019 after completing her residency in anesthesiology and critical care at Government Medical College in Chandigarh, India. She is collaborating with the cardiac anesthesiology research team on studies aimed at determining the cause-and-effect relationship between post-operative condition and cognitive dysfunction, as well as pursuing her academic anesthesiology interests under Dr. Subramaniam's mentoring. Improved perioperative patient outcomes, pain management, and the development of safe anesthesia techniques are among her research interests. In this video Dr. Khera discusses Dexmedetomidine and IV Acetaminophen for the Prevention of Postoperative Delirium Following Cardiac Surgery.
Link to Abstract-
Brief Summary: Based on different postoperative sedation and analgesia regimens, researchers will analyze the incidence and duration of postoperative delirium in patients 60 years old following coronary artery bypass grafting (CABG) with/without valve surgery (aortic and/or mitral). Patients will either get IV dexmedetomidine and IV acetaminophen, or normal postoperative care with IV propofol and morphine or hydromorphone. In these patients, the Confusion Assessment Method (CAM) will be utilized to assess delirium. The researchers also want to examine the analgesic needs of individuals with and without IV acetaminophen 48 hours after surgery. Finally, researchers will use a cognitive assessment scale to assess postoperative cognition in post-surgical patients up to one year after discharge.
Description in detail:
A total of 120 patients were randomized and received a study intervention in this prospective, randomized, placebo-controlled, triple-blinded, factorial design investigation. The typical sedation/analgesic propofol and opioid regimen will be compared against intravenous dexmedetomidine and acetaminophen.
After giving their informed agreement, study participants will be randomized by an unblinded investigator and given a precise mix of sedatives and analgesics. IV propofol or IV dexmedetomidine will be used as sedatives, and IV acetaminophen or placebo will be used as analgesics (100 mL 0.9 percent NaCl equivalent to the administered volume of IV acetaminophen). The following four treatment arms will be assigned to subjects in the following order: 1:1:1:1:1:1:1:1:1:1:1:1:1:1:1:1:1:1: IV acetaminophen with IV propofol, IV acetaminophen with IV dexmedetomidine, IV propofol with placebo, IV dexmedetomidine with placebo, IV propofol with placebo While patients are in the operating room, sedation and analgesic techniques will begin and continue as they are moved to the Cardiovascular Intensive Care Unit (CVICU). Weight-based sedation drugs will be used (a loading infusion of 0.5-1 g/kg over 10 minutes followed by a maintenance infusion of 0.1-1.4 g/kg/hr for IV dexmedetomidine or 20-100 g/kg/min for IV propofol). Patients are given postoperative anesthesia 4-6 hours before being awakened in the CVICU. Patients randomized to this treatment will receive IV acetaminophen (1g or 100mL) every 6 hours for 48 hours. In each group, the same amount of placebo will be given in the same amount of time. In all patients, oral acetaminophen will be continued until discharge. For breakthrough pain, all groups will receive bolus doses of opioids (IV morphine or hydromorphone).
A blinded investigator will deliver a preoperative (baseline) and a series of post-operative examinations to patients to assess delirium. The Montreal Cognitive Assessment (MoCA), days of the week (DOW), months of the year (MOY), Delirium Symptom Interview (DSI), Geriatric Depression Scale (GDS), and the Confusion Assessment Method will all be used as baseline tests (CAM). The DSI, CAM, and a standard cognitive exam will be used in daily cognitive tests. The MoCA, DOW, MOY, DSI, and CAM will be provided at discharge. The telephonic MoCA, DSI, GDS, and CAM will be used in follow-up evaluations one month and one year after discharge. The treating professionals will not be given the delirium research assessments. Clinicians will assess and treat delirium as usual, including reversible cause assessment and correction, behavioral management, and the administration of IV haloperidol for agitation as needed. The study will keep track of haloperidol rescue doses.
All individuals' blood will be drawn at the baseline assessment, on post-operative day 1 (POD1) in the ICU, on POD 2 in the ICU, and within 48 hours of discharge. At each time point, two sets of 10 mL of blood will be collected, for a total of 80 mL of blood per patient. At baseline, efforts will be made to take blood efficiently through the patient's arterial line or to supplement planned draws using phlebotomy. The buffy coat and plasma will be removed from the blood, aliquoted into labeled vials, and kept at -80°C for future use in a biomarker bank.
The following are the primary outcome measures:
Delirium Incidence [Timing: Participants will be tracked for the remainder of their hospital stay, which is usually 5 days]
The incidence of delirium will be compared between patients who received IV acetaminophen and those who did not, starting 24 hours after surgery and continuing daily until discharge. According to the Confusion Assessment Method, delirium is characterized as an acute shift in pre-operative baseline condition with added symptoms of inattention, disordered thinking, and altered loss of consciousness (CAM).