Introduction to StO2 Monitoring

Assess Tissue Perfusion Rapidly & Noninvasively

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InSpectra StO2 Systems

Ardolic, Ann Emerg Med. 2010;56:S131.Cohn, J Trauma. 2007;62:44.Moore, Int Proc TSIS 2007;111.

Quick assessment helps identify hypoperfused patients in

seconds

Continuous monitor tracks a patient’s response

to interventions

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What Is StO2?

SaO2 and SpO2

measure O2

saturation in the

arteries.

ScvO2 measures O2

saturation in the superior vena cava.

SvO2 measures O2 saturation in the pulmonary

artery.StO2 measures O2 saturation in the microcirculation,

where O2 diffuses to tissue cells. Direct measure of tissue oxygenation and sensitive indicator of tissue perfusion status.

InSpectra StO2

StO2 = hemoglobin oxygen saturation of the microcirculation

SaO2

SpO2

ScvO2

SvO2

Cohn, J Trauma. 2007;62:44Lima, Crit Care. 2009;13(Suppl 5):S13

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Why Measure Thenar Muscle?

During shock, blood flow to peripheral muscles and core organs (liver, gut and kidneys) is reduced in order to preserve brain and heart oxygenation

Thenar muscle group is peripheral muscle

StO2 measured in thenar allows noninvasive monitoring of early changes in perfusion status during shock and resuscitation

Thenarmuscles

Chalmers, J Physiol. 1967;192:561.Beilman, Shock. 1999;12:196.

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StO2 measurement site

Thenar site minimally affected by

– age

– gender– edema– adipose

StO2 not confounded by hypothermia

Crookes, J Trauma. 2005;58:806.Poeze, Int Care Med. 2006;32:788.Beilman, Ann Surg. 2009;249:845.

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How Does the Technology Work?

Animation image to be inserted

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Watching the Value; Watching the Trend

Low StO2 is associated with poor outcomes and should be investigated

75%

100%

0%

StO2 low;assess patient;

resuscitate if indicated

StO2

rising toward normal; assess continued

resuscitation

StO2 falling; assess patient;

resume resuscitation if indicated

StO2 high; usually seen in

systemic vasodilation and high CO

StO2 adequate; assess need for

further resuscitation; stop if indicated

StO

2

Cohn, J Trauma. 2007;62:44. Leone, Anesthesiology. 2009;111:366.Lima, Crit Care. 2009;13(Suppl 5):S13. Sagraves, J Trauma. 2009;67:441.

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Stratify Risk & Guide Resuscitation

Low StO2 is associated with poor outcomes• Organ dysfunction• Mortality

Incidence of low StO2 is high even when vital signs are not alarming

Cohn, J Trauma. 2007;62:44. Veening, Crit Care. 2010;14(Suppl 1):P151.Lima, Crit Care. 2009;13(Suppl 5):S13 Leone, Anesthesiology. 2009;111:366.Sagraves, J Trauma. 2009;67:441

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Emergency Medicine

Patients Who May Benefit

High Acuity ElderlyHigh Acuity Elderly Trauma Trauma

• Any age

• Mechanism of injury puts at risk for bleeding

• May have non-alarming vital signs

Medical BleedingMedical Bleeding

• All patients at risk for bleeding/suspected of internal bleeding:

-Gastrointestinal-Vaginal-Nasal

• Over 65 years old with:

-Shortness of breath-Chest pain-Abdominal pain-Falls-Weakness-Syncope

Critical Care

Patients described above Patients considered to be resuscitated; have non-alarming clinical signs Patients requiring active treatment

Veening, Crit Care. 2010;14(Suppl 1):P151.Ardolic, Ann Emerg Med. 2010;56:S131.

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References

Ardolic B et al. The Incidence of Hypoperfusion In Patients Waiting for a Medical Floor Bed. Annals Emerg Med. 2010;56(3):S131.

Beilman GJ et al. Early hypothermia in severely injured trauma patients is a significant risk factor for multiple organ dysfunction syndrome but not mortality. Ann Surg. 2009;249(5):845-850.

Beilman GJ et al. Near-infrared spectroscopy measurement of regional tissue oxyhemoglobin saturation during hemorrhagic shock. Shock. 1999;12(3):196-200.

Chalmers JP et al. Effects of hemorrhage on the distribution of the peripheral blood flow in the rabbit. J Physiol. 1967;192:561-574.

Cohn SM et al. Tissue oxygen saturation predicts the development of organ dysfunction during traumatic shock resuscitation. J Trauma. 2007;62(1):44-55.

Crookes BA et al. Can near-infrared spectroscopy identify the severity of shock in trauma patients? J Trauma. 2005;58(4):806-816.

Leone et al. Oxygen Tissue Saturation Is Lower in Nonsurvivors than in Survivors after Early Resuscitation of Septic Shock. Journal of the American Society of Anesthesiologists. August 2009: Vol 111 issue 2

Lima et al. Low tissue oxygen saturation at the end of early goal-directed therapy is associated with worse outcome in critically ill patients. Crit Care. 2009;13(Suppl 5):S13.

Moore FA. Tissue oxygen saturation predicts the development of organ failure during traumatic shock resuscitation. In: Faist E, ed. International Proceedings of the 7th World Congress on Trauma, Shock, Inflammation and Sepsis. Munich, Germany, 13-17 March 2007. Bologna, Italy: Medimond; 2007:111–114.

Poeze, M. Tissue-oxygenation assessment using near-infrared spectroscopy during severe sepsis: confounding effects of tissue edema on StO2 values. Int Care Med. 2006;32(5):788-789.

Sagraves et al. Tissue Oxygenation Monitoring in the Field: A New EMS Vital Sign, J Trauma. September 2009: Vol 67 No. 3

Veening et al. Incidence of a low tissue oxygen saturation in a mixed population of critically ill patients. Crit Care. 2010;14(Suppl 1):P151.

InSpectraTM StO2 Measurement Systems noninvasively measure an approximated value of percent hemoglobin oxygen saturation in thenar skeletal muscle tissue (StO2). Visit us online at www.htibiomeasurement.com for full Instructions for use. ©2011 Hutchinson Technology Inc. 5027648 G 07/12 All Rights Reserved. Rx Only.