The Critical Care and Perioperative Population Health Research (CAPER) Unit


Duke Anesthesiology’s Critical Care and Perioperative Population Health Research (CAPER) Unit launched in April 2019. CAPER’s mission is to improve the lives of patients undergoing surgery and critical care globally, through the conduct of large-scale observational research using rigorous population health methods.

Message from the Directors

Vijay Krishnamoorthy, MD, PhD & Karthik Raghunathan, MBBS, MPH

Vijay Krishnamoorthy, MD, MPH, PhD & Karthik Raghunathan, MBBS, MPH

Welcome to Duke Anesthesiology’s Critical Care and Perioperative Population Health Research (CAPER) Unit! Through a foundation built on the rigorous methodologic principles of epidemiology and health services research, our unit aims to fill the gap between basic science research and clinical trials, by conducting high-quality observational research to advance knowledge in the care of perioperative and critically ill patients. We are comprised of a methods core (methodologists, analysts and data sources), subject-matter experts and a diverse membership who are all dedicated to advancing outcomes research in the fields of critical care and perioperative medicine. Through this, our goal is to improve health outcomes in perioperative and critically ill populations, both locally and globally. Please explore our website and feel free to contact us if you would like to be a part to this diverse and exciting group!

Core Operating Values

The following core operating values influence the culture and public image of the Critical Care and Perioperative Population Health Research (CAPER) Unit as an effective organization to improve the public’s health through research, education, and collaboration.

With humility and curiosity, it seeks answers to questions posed by patients, families, clinicians, and others interested in the delivery of high-quality perioperative and critical care. The CAPER Unit will conduct work with the following core values:

  • Caring Attitude
  • Respectfulness
  • Diversity
  • Integrity and Accountability
  • State of the Art Practices
  • Collaboration
  • Education
  • Financial Sustainability

What We Do

To achieve our mission of improving the lives of patients undergoing surgery and critical care globally, the CAPER Unit conducts rigorous observational research grounded in our core competencies (epidemiology, health services research, comparative effectiveness, and causal inference).

Our vision is to excel at our core competencies to generate new knowledge, collaborate in key domains (health economics, health policy, and implementation science) to convert this knowledge into practice, and become global leaders in perioperative/critical care population health research.

Why Do We Need?

Why is rigorous population health research needed in critical care and perioperative medicine?

There are several factors that have contributed to the need for rigorous population health research in critical care and perioperative medicine:

  1. The evidence base is lacking for much of daily clinical practice, particularly when data from randomized-controlled clinical trials (RCT) are limited.
  2. Health care costs have skyrocketed, forcing stakeholders to consider the value of medical care. For example, critical care accounts for greater than one percent of the gross domestic product of the United States, and is expected to rise further.
  3. There has been a dramatic rise in the volume of health care data available, with a concurrent advancement in statistical techniques and computing capabilities.
  4. Advancing health equity in critical care and perioperative medicine is a priority.
  5. The results of observational clinical studies are sometimes biased, often due to poor methodologic rigor. This is especially relevant, as millions of dollars in research funding are poured into clinical trials that are based on preliminary observational data.

Why do we need a Critical Care and Perioperative Population Health Research Unit at Duke Anesthesiology?

The unique nature of critical care and perioperative research requires a specialized group conducting diverse research, while applying a core set of foundational methods that can help to fill gaps in evidence and advance patient care. Because of the combination of world leaders with subject matter expertise in a variety of critical care and perioperative domains with methodologists that have expertise in population health research within Duke Anesthesiology, the CAPER Unit harmonizes these areas. The CAPER unit organizes its strengths in a diverse variety of domains in critical care and perioperative medicine under a common methodologic framework.

CAPER Research Graphic


The CAPER Unit focuses its research around five major pillars:

CAPER - Methods

Improving the rigor of observational research through methodologic innovation

CAPER - Injury Epidemiology

Examining trauma, the opioid epidemic, and public health

CAPER - Resuscitation, Analgesia, and Nutrition

Comparative effectiveness of common critical care and perioperative interventions

CAPER - Multi-Organ Dysfunction

Studying organ dysfunction and clinical outcomes in critical care and perioperative medicine

CAPER - Learning Health

Moving from “data to knowledge” to “knowledge to practice”

Project Examples

  1. Examination of the use of capture-recapture methods to optimize ascertainment of exposures and outcomes in perioperative and critical care research
  2. Examination of natural experiment designs (coupled with Roger’s diffusion curve) to reduce residual confounding in observational perioperative research
  3. Improving methods for before-after studies in perioperative research
  4. Review of advanced methods for reducing cofounding in perioperative and critical care research (mediation analysis, natural experiment design, instrumental variable analysis, propensity scores, and interrupted time series)

Project Examples

  1. Mechanisms and clinical impact of myocardial dysfunction following traumatic brain injury
  2. Multi-organ dysfunction following traumatic brain injury
  3. Optimizing early hemodynamic management in adult and pediatric traumatic brain injury
  4. Trends and variation in healthcare utilization following severe acute brain injury
  5. Racial and ethnic disparities in healthcare utilization following severe acute brain injury
  6. Systematic review of incidence of multi-organ dysfunction following moderate-severe traumatic brain injury
  7. Examination of impact of ICU care on outcomes following traumatic brain injury in Tanzania
  8. Clinical epidemiology of moderate traumatic brain injury in low and middle-income countries
  9. Descriptive epidemiology of outcomes (healthcare utilization, readmission, mortality, violence, arrest) following emergency room visit for opioid overdose
  10. Opioids following surgery in the United States and impact of the Veteran’s Affairs Opioid Safety Initiative
  11. Guideline adherence for multimodal analgesia in TKA (VA versus non-VA)

Project Examples

  1. Association of FDA warning (reading hydroxyethyl starch) with bleeding outcomes following musculoskeletal surgery in the United States
  2. Unintended consequences of albumin for perioperative resuscitation
  3. Balanced fluids versus saline on outcomes in critically ill patients: mediating effects of chloride level
  4. Progression of chronic kidney disease following major abdominal surgery: effect modification by baseline renal function
  5. Heart-rate and blood-pressure coupling in perioperative medicine
  6. Effect of oral nutrition supplements on perioperative outcomes
  7. Joint and combined effects of multimodal analgesia in perioperative medicine

Project Examples

Pulmonary Outcomes

  1. Examination of the introduction of Sugammadex on post-op respiratory failure
  2. Perioperative lung-protective ventilation strategies
  3. SCCM Discovery Network SAGE Study

Neurological Outcomes

    1. Association between gonadal hormones on ICH pathophysiology and outcome
    2. Affects of blood pressure agent class used after ICH  on hematoma growth and mortality
    3. Use of SSRIs prior to ICH affects long-term outcome
    4. Incidence, mediators, and outcome of ARDS after ICH
    5. Defining associations between serum, CSF, and radiographic biomarkers with acute ICH pathophysiology and long-term outcome

Project Example

  1. Duke Health System ICU Registry


Our research is funded through department, industry, foundation, and federal sources. Examples of current funding sources include:

CAPER Funding

Not only do the CAPER members produce excellent science, but they are dedicated to supporting the early careers of clinician scientists.

Duncan McLean, MB, ChB

Meet the Team

Duke Advisory Board

Lesley H. Curtis, PhDLesley H. Curtis, PhD
Professor in Population Health Sciences & Medicine

Adrian F. Hernandez, MD, MHSAdrian F. Hernandez, MD, MHS
Professor of Medicine

Joseph P. Mathew, MD, MHSc, MBA, FASEJoseph P. Mathew, MD, MHSc, MBA
Jerry Reves, MD, Professor of Anesthesiology

Senior Scholars

Atilio Barbeito, MD, MPHAtilio Barbeito, MD, MPH
Associate Professor of Anesthesiology

Ashraf S. Habib, MBBCh, MSc, MHSc, FRCAAshraf S. Habib, MBBCh, MSc, MHSc, FRCA
Professor of Anesthesiology

Krista Haines, MA, DOKrista L. Haines, MA, DO
Assistant Professor of Surgery

Michael L. James, MD, FAHA, FNCSMichael L. James, MD, FAHA, FNCS
Associate Professor of Anesthesiology

Michael Kent, MDMichael L. Kent, MD
Associate Professor of Anesthesiology

Jordan M. Komisarow, MDJordan M. Komisarow, MD
Assistant Professor of Neurosurgery

Vijay Krishnamoorthy, MD, MPH, PhDVijay Krishnamoorthy, MD, MPH, PhD
Associate Professor of Anesthesiology

Yi-Ju Li, PhDYi-Ju Li, PhD
Professor of Biostatistics and Bioinformatics

Ryan C. McDevittRyan C. McDevitt
Professor of Business Administration

Steve Melton, MDSteve Melton, MD
Assistant Professor of Anesthesiology

Marie-Louise Meng, MDMarie-Louise Meng, MD
Assistant Professor of Anesthesiology

Galen Royce-Nagel, MDGalen Royce-Nagel, MD
Assistant Professor of Anesthesiology

Tetsu Ohnuma, MD, MPHTetsu Ohnuma, MD, MPH
Associate in Research

Nosayaba Osazuwa-Peters, MPH, PhDNosayaba Osazuwa-Peters, MPH, PhD
Assistant Professor in Head and Neck Surgery & Communication Sciences

Jamie Privratsky, MD, PhDJamie R. Privratsky, MD, PhD
Assistant Professor of Anesthesiology

Srinivas Pyati, MDSrinivas Pyati, MD, MBBS
Assistant Professor of Anesthesiology

Karthik Raghunathan, MBBS, MPHKarthik Raghunathan, MBBS, MPH
Associate Professor of Anesthesiology

Rebecca Schroeder, MDRebecca A. Schroeder, MD
Associate Professor of Anesthesiology

Shreyansh Shah, MBBSShreyansh Shah, MBBS
Assistant Professor of Neurology

Annemarie Thompson, MDAnnemarie Thompson, MD
Professor of Anesthesiology

David A. Williams, MD, MPHDavid A. Williams, MD, MPH
Assistant Professor of Anesthesiology

Paul E. Wischmeyer, MD, EDICPaul E. Wischmeyer, MD, EDIC
Professor of Anesthesiology

Marc J. Pepin, PharmD, BCPS, BCGPMarc J. Pepin, PharmD, BCPS, BCGP
Clinical Pharmacy Specialist, Geriatrics
PGY2 Geriatric Pharmacy Residency Program Director
Durham VA Health Care System


Matthew FullerMatthew Fuller



Megan Fah, MDMegan Fah, MD

Selby Johnson, MDSelby Johnson, MD

Sachin Mehta, MDSachin Mehta, MD

Sean Moore, MDSean Moore, MD


Vincent Brinker, MDVincent Brinker, MD

Fintan Hughes, MB, BCh, BAOFintan Hughes, MB, BCh, BAO

Suhas Kochat, MD, MBASuhas Kochat, MD, MBA

Kathryn Pearson, MDKathryn Pearson, MD

Sydney Reed, MDSydney Reed, MD

Medical Students

Zach Frere
MS candidate, Duke University School of Medicine, Department of Biostatistics

Riley LeagueRiley League
PhD Student in Economics

Camilo ToroCamilo Toro
MD Candidate, Duke University School of Medicine


The CAPER Unit will leverage its existing collaborations (for SMEs, data and analytic support) with additional new collaborations at Duke to enhance its ability to conduct the most rigorous outcomes research in perioperative and critical care medicine.

CAPER Collaborations

Updates & Announcements

CPOP Seminar Series
Twice a month
5 – 6 PM | MSRBIII, Room 1125

Contact Us

Critical Care and Perioperative Population Health Research (CAPER) Unit
40 Duke Medicine Circle
DUMC 3094
Durham, NC 27710

Lauren Brooks

Chris KeithCritical Care and Perioperative Population Health Research (CAPER) Unit