Advancing Physiologic Science

Advancing physiologic science and emerging medical technologies through rigorous human testing

Areas of Research

The UCSF Hypoxia Lab has unique capacity to conduct a wide range of studies aimed at advancing understanding of human physiology and improving technologies that measure physiologic signals, including oxygen saturation, heart rate, blood pressure, cerebral blood flow, and hemoglobin concentration. We perform physiologic studies to support the development and regulatory verification of medical devices and AI algorithms. Our novel protocols assess performance across diverse populations, including different ages, genders, body sizes, and skin tones. The lab operates as an independent, nonprofit testing facility within UCSF, in collaboration with the UCSF Center for Health Equity in Surgery & Anesthesia, the UCSF epochAI Lab, and the Uganda Hypoxia Lab.

Physiologic Sensor Development

Regulatory Verification Testing

Real World Clinical Trials

Regulatory Science

Human Adaptation to High Altitude

Predictive Machine Learning

Standard Pulse Oximeter Study in San Francisco

We determine the accuracy of pulse oximeters by exposing volunteers to short periods of low oxygen levels (75-100% SaO2) while monitoring how the oximeter responds. This helps us understand if these devices are accurate for everyone regardless of skin color during these low oxygen conditions.

Standard Pulse Oximeter Study in Uganda

Motion Testing

During pulse oximetry testing, we can include tools that mimic patient movements. These tools, which come from the manufacturer, are called motion fixtures. They help us simulate scenarios where a patient might be moving, allowing us to see how well the pulse oximeters perform in situations with motion during low oxygen conditions.

Methemoglobin Study

We assess pulse oximeters tailored for detecting methemoglobin (metHb), a hemoglobin type not carrying oxygen as usual. To ensure if pulse oximeters reliably detect elevated metHb levels during low-oxygen conditions, volunteers undergo brief low-oxygen exposure (75-100% SaO2) while we observe oximeter responses.

Carboxyhemoglobin Study

We assess pulse oximeters tailored for detecting carboxyhemoglobin (COHb), a hemoglobin type not carrying oxygen as usual. To ensure if pulse oximeters reliably detect elevated COHb levels during low-oxygen conditions, volunteers undergo brief low-oxygen exposure (75-100% SaO2) while we observe oximeter responses.

Cerebral Oximetry Study

We’re studying cerebral oximeters to gauge their accuracy in measuring brain oxygen levels. Comparing readings with direct blood measurements from the artery (SaO2) and jugular vein (SjvO2) helps us assess performance, particularly when arterial oxyhemoglobin saturation (SaO2) is between 70% and 100%.

Low Perfusion Testing

With low perfusion testing, we can simulate low perfusion (reduced blood flow) using clamps or cuffs. We can also test in various body positions, like the Trendelenburg position. This allows us to examine how well devices perform under low oxygen conditions (75-100% SaO2) where blood flow may be limited or changed.

Transcutaneous Carbon Dioxide Sensor Testing

We’re testing transcutaneous carbon dioxide sensors to see how well they monitor carbon dioxide levels in the blood. We’re examining their performance alone and when used with pulse oximetry and desaturation of oxyhemoglobin (a component of the blood that carries oxygen).

Drug-Induced Apnea Testing

Using medications like Propofol and Remifentanil, we induce temporary breathing pauses (apneic events) to simulate opioid-related respiratory slowdown. The aim is to evaluate how effectively the oximeter combination can identify this reduced oxygen condition, crucial for monitoring patients in these specific medical situations.

Neonatal Accuracy Testing

To ensure pulse oximeters work effectively in diverse scenarios, we test them on neonates undergoing heart surgery, where physiological conditions change. Multiple blood samples are taken, providing insights into oximeter performance amidst rapidly changing variables.

Profound Hemodilution Study

This study aims to assess the accuracy of new non-invasive pulse oximeters, measuring total blood hemoglobin without skin puncture. By temporarily removing and re-infusing blood in healthy volunteers (isovolemic hemodilution), we induce changes in hemoglobin concentration.