CURRENT RESEARCH PROJECTS

Dr. Pratik Pandharipande

His primary research focuses on cognitive and health related quality of life impairments during and after critical illness. Active areas of research include modifying sedation paradigms to improve outcomes, studies investigating genetic, demographic, environmental, and hospital acquired risk factors for long-term cognitive, mental and functional impairments, and rehabilitation and prehabilitation programs to reduce the impact of critical illness of long term quality of life in survivors of critical illnesses.

Ongoing studies include:

  1. "Maximizing the Efficacy of sedation and reducing Neurological Dysfunction in Septic patients (MENDS2 study). The specific aims of this study are to determine whether sedation of mechanically ventilated severely septic patients with an alpha2 agonist (dexmedetomidine) rather than a GABAergic agent (propofol) will increase days alive without delirium or coma (delirium/coma-free days), and reduce mortality and neuropsychological dysfunction.
  2. Prevalence and Risk Factors for PTSD in Veteran and Civilian populations. The specific aims of this project to evaluate the prevalence rates of PTSD using DSM IV symptom matching and assess the role of delirium, depression and sedative use in PTSD after critical illness.
  3. Biomarkers for Delirium and Cognitive Impairment. The specific aims of this study are to evaluate the role of inflammation and coagulation factors in delirium and long-term cognitive impairment

Dr. Christopher Hughes

His primary research focuses on the roles of endothelial dysfunction and blood brain barrier injury in cognitive dysfunction after acute medical and surgical illness and designing therapeutic regimens that modify these pathways to improve patient outcomes.

Ongoing studies include:

  1. Evaluating the mechanistic roles of endothelial activation, blood brain barrier and brain injury, and neuroinflammation in delirium and long-term cognitive impairment after critical illness in the elderly.
  2. PI for the MENDS2 study of dexmedetomidine vs. propofol for sedation of septic patients on mechanical ventilation.

GEMSSTAR R03


Dr. Joseph Schlesinger, II

His primary research focuses on Multisensory integration, human factors, aural perception, temporal precision, alarm development, patient monitoring, impact of noise on ICU delirium and PTSD, and medical education.

Ongoing studies include:

  1. Utilizing Multisensory Integration to Improve Monitoring in the Intensive Care Unit.
  2. Using multisensory alarms (audio and visual) to determine psychoacoustic qualities and optimal signal-to-noise ratio presentations to improve practitioner performance and ameliorate alarm fatigue.
  3. Determining optimal ICU rounding patterns to improve attentional reserve and executive function gauged by the stop-signal reaction task.

Elizabeth Heitman, PhD

Fogarty International Center/NIH #R25 TW009722-01, "VU-Mozambique Collaborative Research Ethics Education Program", E Heitman, T Moon, co-PI's, May 2014 - Dec 2018. A 5-year collaborative education program in Mozambique designed to build capacity among members of Mozambican research ethics committees for review of research protocols, increase awareness and understanding of national and international standards of research ethics and scientific integrity among Mozambican researchers, and develop relevant curricular material in research ethics in Portuguese.

NINDS "1U10NS086492, "The Vanderbilt Stroke Trials Network Regional Coordinating Center for Tennessee", HS Kirshner, PI, E Heitman, Co-Investigator, Sept 2013 - July 2018. A 4-year grant to increase the evidence base for the treatment of stroke through clinical trials, the ethics component of this program is still largely advisory.

NHLBI #1R25HL126145-01, "HBCU PRIDE Program", B Beech, PI, E Heitman, PI on $22,831 subaward to Vanderbilt University, Co-Investigator, Sept 2014 - May 2018. A 4-year research education and training grant to increase the capacity and number of African American social science and public health investigators in obesity research, HBCU Pride will provide a 10 day boot camp and ongoing mentoring to a 3 annual cohorts of young investigators from across the region.


Dr. Antonio Hernandez

His primary research focuses on the use of immunoadjuvants for enhancing the innate immune function and tissue reconditioning.

Ongoing studies include:

  1. Enhancing of Innate Anti-microbial Immunity via TLR4 Agonists. E Sherwood, PI, A Hernandez, Co-Investigator.

Dr. Frederic T. (Josh) Billings IV

His primary research focuses on intraoperative oxidative injury of surgery-induced kidney injury. He hypothesizes that intraoperative excess oxygen administration, hemolysis, and mitochondrial dysfunction are each intraoperative modifiable risk factors that increase production of free radicals, and that excess radical production increases postoperative kidney, brain, and heart dysfunction, leading to poor patient outcomes.

Ongoing studies include:

  1. Our research program focuses on mechanisms of surgery-induced acute kidney injury (AKI), namely intraoperative oxidative damage, and developing new therapy for AKI in humans. Our 445 subject Atrial Fibrillation and Renin Angiotensin Aldosterone System RCT demonstrated that intraoperative oxidative injury, rather than acute inflammation or anti-fibrinolysis, independently predicts postoperative AKI and that perioperative statin use is associated with a decreased incidence of AKI.
  2. Based on those findings, we designed and have now enrolled over 650 patients into the Statin AKI Cardiac Surgery RCT, testing the hypotheses that short-term, high does, perioperative atorvastatin reduces oxidative damage and AKI compared to placebo. Assessments of intraoperative oxygen administration and markers of mitochondrial dysfunction (both contributors to increased reactive oxygen species (ROS) production), oxidative damage, and postoperative AKI within this cohort led us to hypothesize that excess oxygen administration during surgery increases ROS production, increases oxidative damage, and increase postoperative morbidity including AKI, delirium, and myocardial injury.
  3. To test this hypothesis, we initiated the Risks of Oxygen during Cardiac surgery (ROC) trial in January 2015 in which we randomize cardiac surgery patients to hyperopia or normoxia during surgery and measure ROS production, oxidative injury, and postoperative morbidity. In the laboratory, we have been performing additional ex vivo studies of whole blood and circulating peripheral blood mononuclear cells to improve our understanding of the subcellular sources of ROS hemoglobin, mitochondria, or NADPH oxidases and the direct effects of increasing oxygen tension or ROS production.