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Circulatory shock can lead to death or severe complications, if not promptly diagnosed and effectively treated. Typically,
diagnosis and management of circulatory shock are guided by blood pressure and heart rate. However, these variables have
poor specificity, sensitivity, and predictive value. Early goal-directed therapy in septic shock patients, using central venous
catheterization (CVC), reduced mortality from 46.5% to 30%. However, CVC is invasive and complication-prone. We
proposed to use an optoacoustic technique for noninvasive, rapid assessment of peripheral and central venous oxygenation. In
this work we used a medical grade optoacoustic system for noninvasive, ultrasound image-guided measurement of
central and peripheral venous oxygenation. Venous oxygenation during shock declines more rapidly in the periphery
than centrally. Ultrasound imaging of the axillary [peripheral] and internal jugular vein [central] was performed using
the Vivid e (GE Healthcare). We built an optoacoustic interface incorporating an optoacoustic transducer and a standard
ultrasound imaging probe. Central and peripheral venous oxygenations were measured continuously in healthy
volunteers. To simulate shock-induced changes in central and peripheral oxygenation, we induced peripheral
vasoconstriction in the upper extremity by using a cooling blanket. Central and peripheral venous oxygenations were
measured before (baseline) and after cooling and after rewarming. During the entire experiment, central venous
oxygenation was relatively stable, while peripheral venous oxygenation decreased by 5-10% due to cooling and
recovered after rewarming. The obtained data indicate that noninvasive, optoacoustic measurements of central and
peripheral venous oxygenation may be used for diagnosis and management of circulatory shock with high sensitivity and specificity.
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