Direct Cellular Oximetry for Monitoring Patient Health

Clinical Need

Opticyte is focused on delivering a real-time cellular oximeter that will take the guesswork out of knowing patient oxygen status and response to treatment.

One of the primary goals of clinicians caring for critically ill patients is to restore and maintain sufficient oxygen levels in the body’s tissues and organs. Prolonged periods of low tissue and organ oxygen levels lead to clinical shock, resulting in multiple organ failure, loss of limbs and death.

 

Current measurement methods are too slow or rely on indirect clinical information, leaving clinicians guessing at patient condition, treatment protocol, and treatment effectiveness.  Clinicians need a device that provides direct monitoring of cellular oxygenation to provide real-time information on patient condition and treatment effectiveness. This will allow clinicians in intensive care, surgery, and emergency medicine to diagnose and monitor many challenging conditions, most notably:

 

  • Septic shock
  • Traumatic shock (hemorrhage)
  • Cardiogenic shock (heart attack)
  • Congestive heart failure (heart doesn’t pump blood as well as it should)
  • Peripheral artery disease
  • Diabetes

 

Of all these conditions, septic shock represents the most significant clinical need and opportunity for the Opticyte cellular oximetry technology.

 

What is Septic Shock?

Shock is a life-threatening condition that occurs when the body is not getting enough blood flow. As a result, cells and organs do not receive enough oxygen and nutrients to function properly.

 

 

In a healthy body, cells are perfused with blood being routed through the local capillary beds. The capillary blood delivers oxygen and nutrients to cells and carries away cellular waste products. During septic shock, capillary bed blood flow is disrupted by the presence of infection. Septic shock is a serious condition, defined by the body’s inability to respond to fluid replacement. If this condition persists, cells begin to die from lack of oxygen – ultimately leading to organ failure or death.

 

Sepsis represents one of the most challenging issues facing the U.S. healthcare system today:

 

  • Sepsis is #1 medical cost in US hospitals, costing $20 billion annually
  • Sepsis can lead to septic shock, resulting in tissue damage, organ failure, and death
  • 28-50% death rate for ICU sepsis patients in the US
  • Over 268,000 deaths per year in US

 

How is Shock Measured Today?

There are several methods currently used for indirectly estimating oxygen levels in tissues and organs when clinical shock is suspected.

 

  • Most commonly, physicians will monitor heart rate and blood pressure. Because blood pressure is maintained over a wide range of cardiac output values, limited compensatory changes in cardiac output may not be noticed clinically, and the presence of tissue hypoxia (low oxygen levels in tissue) may not always be noticed. This leaves clinicians guessing as to the condition of their patient.

 

  • Intermittent blood sampling may be used to determine the presence of lactate, a metabolic response to cellular hypoxia.  This metabolic response is not immediate, making lactate a lagging indicator of shock at best.  Also, lactate is not a continuous measurement – measured about once per hour – further delaying the immediacy needed for life-saving intervention.

 

  • Invasive catheters can be placed to continuously monitor arterial and venous blood oxygen, but catheters are expensive and require expertise not always available in the emergency department.

 

  • Pulse oximeters are widely used to measure the oxygen bound to hemoglobin in arterial blood. A reading of “normal” from a pulse oximeter indicates that blood is circulating and gas is exchanging in the lungs. However, pulse oximeters readings do not monitor tissue perfusion and therefore do not indicate what is happening in the cells.  Pulse oximeters do not indicate the presence of shock.

 

How Does the Opticyte Cellular Oximeter Compare to a Pulse Oximeter?

Whereas pulse oximetry readings provide information about the oxygen supply in arterial blood, our novel Opticyte technology directly measures oxygen in the cells, where it is needed and used.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Experimental Data

In a trauma patient admitted to the emergency department, Opticyte’s CellSat™ technology continuously monitored cellular oxygenation.  When cellular oxygen levels dipped to dangerous levels, pulse oximetry showed no warning signs. After administering two fluid boluses, cellular oxygen levels were stabilized.

 

Pulse oximetry readings may appear unchanged while cellular oxygen levels are headed in a dangerous downward trend.

Direct monitoring of cellular oxygen clearly represents the “Holy Grail” of effective shock detection and treatment. Opticyte’s novel technology will soon allow clinicians an unprecedented view into the oxygenation status of their critically ill patients.

Opticyte, Inc.

University of Washington

Box 352141

4000 Mason Road, Suite 300

Seattle, WA 98195