Heart rate measurements.

<p>Data from the arterial pressure catheter (grey) and the telemetry sensor (black).</p

Hepatic flow changes.

<p>(Left) Changes in total hemoglobin concentration (ΔHbT, black dots) in hepatic tissue versus total hepatic flow measured by the addition of the HA and PV Transit-Time flowmeters' measurements (grey line). (Right) Total hepatic flow (grey) and mean arterial pressure (black) trends show that the increase in flow after t = 200 min is accompanied by an increase in the arterial pressure suggesting that a systemic response is responsible for that increase.</p

Hepatic flow changes prior to the increase in blood pressure.

<p>(Left) Total hemoglobin concentration (ΔHbT) and flow changes. (Right) Scatter plot of measured hemoglobin concentration change (ΔHbT) vs. tissue perfusion (flow normalized by liver weight).</p

Venous oxygen saturation.

<p>Data from the telemetry sensor (black dots) and the central venous catheter (grey line) for study 1 (left) and 2 (right).</p

Scatter plot of the predicted vs. measured MOS for study 1 (black) and 2 (grey).

<p>Scatter plot of the predicted vs. measured MOS for study 1 (black) and 2 (grey).</p

Schematic of the envisioned wireless sensor implanted on the liver.

<p>Schematic of the envisioned wireless sensor implanted on the liver.</p

Flow chart of the signal processing.

<p>This was employed to compute the oxygen saturation at the arterial and venous side along with perfusion changes from the measured AC and DC signals.</p

Typical PPG signal.

<p>a- Schematic of the collected reflectance signal (Note that the various signal components are not drawn to scale to allow easy visualization). b- Spectrum of the reflectance signal collected with our sensor prior to amplification and with the DC signal omitted.</p

Predicted venous oxygen saturation by combining the DC NIRS measurements with the AC pulse oximetry measurements.

<p>Note that the missing values correspond to the periods where MOS dropped below 72% and, because of the previously reported problem with signal from the red wavelength, could not get reliable pulse oximetry measurements. Study 1 & 2 are shown in left & right panel respectively.</p