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Our Research Areas

Our lab is interested in several research themes: OSA Pathogenesis, Sleep in HIV, Sleep in the Hospital, ECMO, ICU Recovery, and Augmented Intelligence.

OSA Pathogenesis

Obstructive sleep apnea (OSA) is increasingly recognized as a multifactorial disorder i.e., different people have OSA for different reasons. Although an anatomical predisposition (collapsibility of the upper airway) is required, other factors are important as well, including a low respiratory arousal threshold (wake up too easily), dysfunction in upper airway dilator muscles and instability in ventilatory control (which we quantify using the engineering term loop gain [LG]), which leads to periods of decreased pharyngeal tone as well periods of increased respiratory effort. I have been actively involved in efforts to characterize the different endotypes - defined as a subtype of a condition that has a distinct functional or pathobiological mechanism - important for OSA.

The ultimate goal of this work is to personalize therapy for OSA one day by addressing the underlying endotype to treat OSA effectively in an individual with targeted therapy.

Currently, we can measure these endotypes through careful manipulation of the airway during the night during sleep, and see how the person's muscles, respiratory drive and arousal mechanisms compensate.

In an individual, we can model how the traits go together.

This is important because two people might have the same severity of OSA for DIFFERENT reasons. Ultimately we hope to treat the underlying cause and personalize therapy.

We do have alternate therapies, such as oral appliances and upper airway surgery, but we are pretty bad at predicting who can use these. With a knowledge of the underlying physiology we can model outcomes from surgery more accurately .

Sleep in HIV

Thankfully, major strides have been made in the treatment of Human Immunodeficiency Virus (HIV) leading to greatly prolonged life expectancy for people on anti-retroviral therapy (ART). However, fatigue and early cardiovascular disease are major problems. Might sleep apnea be a culprit? Here's what we know about OSA in HIV:

1. OSA is appears to be common in those with HIV.

2. Traditional OSA risk factors may not predict OSA in PLWH.

3. Untreated OSA may be relevant for symptoms in PLWH.

4. Untreated OSA is likely to be associated with ongoing inflammation.

5. Few PLWH with OSA are diagnosed or treated.

We are conducting experiments to determine: - If people with HIV are predisposed to OSA - What the impact of sleep and sleep apnea are on fatigue and quality of life in people with HIV.


  • Chuck Hicks MD
  • Maile Karris MD
  • Igor Grant MD
  • Sonia Ancoli Israel PhD
  • Atul Malhotra MD
  • Jeremy Orr MD
  • Dae Kang PhD

Interested in Participating?

If you are in the San Diego area and would like to be considered, please call 858-246-2154 or email These studies are NIH funded and registered on (NCT03064204, NCT03575143)

Sleep in the Hospital

If you've ever been an ICU patient, or had to stay overnight in an ICU, you know that ICUs are not conducive to sleep. Increasingly, studies link lack of sleep to delirium, and efforts to promote sleep can reduce delirium rates. We are very interested in careful measurement of the hospital environment, ways to measure sleep in the hospital/ICU, and ultimately ways to improve sleep and delirium in the hospital. Stuti Jaiswal leads this work.

Here's what we've learned:

1. Hospitals are really loud, but making them more quite might not be the answer. 

2. ICUs aren't too bright at night, they are TOO DIM during the day. 

3. Sleep is really fragmented in the hospital.

4. Unfortunately, it doesn't like seem melatonin or Ramelteon are too helpful to reduce delirium. Also, it seems likely that sleep in the hospital is a problem for family members of ICU patients.

Giang is an ICU nurse we work with to look at this.


Extracorporeal membrane oxygenation (ECMO) is a mechanical life support for refractory respiratory and/or cardiac failure. Our research evaluates biomarker's changes associated with clinical interventions (ventilator changes, prone positioning, etc) for patients on ECMO. Quality improvement ECMO projects include evaluating nurses as the ECMO bedside specialist, physical therapy for severe ARDS patients on ECMO, and anticoagulation.

More about our ECMO Research

ICU Recovery

After an ICU admission, patients often struggle with new, significant problems in thinking, physical activity and mental health, a group of symptoms known as Post-Intensive Care Syndrome, or PICS. With the COVID-19 pandemic, people are increasingly recognizing the importance of diagnosing and treating symptoms of PICS. At UCSD, we have developed an ICU Recovery Clinic designed to do just that. As part of Amy Bellinghausen's work in the ICU Recovery Clinic, she has focused on the ways in which lessons learned in the ICU Recovery Clinic can be used to improve the ICU environment for patients, families and providers. One recent example was that, after patients in the ICU Recovery Clinic reported symptoms of nerve compression which started after they had undergone prone positioning (turned on their stomach to improve oxygenation), the UCSD ICU practice of proning was changed to better prevent this kind of injury. Old and new padding strategies pictured below.

More about our ICU Recovery Research