Current status of tissue monitoring in the management of shock.

PURPOSE OF REVIEW: Tissue monitoring is one of the main strategies at the bedside to guide resuscitation of shock. Advances in tissue monitoring technologies have established noninvasive optical methods and transcutaneous oximetry as modalities of considerable value in the critical care setting for tissue monitoring in shock. The purpose of this article is to highlight the latest developments into the clinical applications of near-infrared spectroscopy, direct visualization of sublingual microcirculation, and transcutaneous oxygen measurements (PtcO2). RECENT
FINDINGS: Near-infrared spectroscopy has been successfully applied in patients with septic shock during vasopressor and blood transfusion therapy to identify patients at high risk for microcirculatory failure. A new generation incident dark field imaging-based handheld microscope has been introduced for quantification of microcirculatory alterations at bedside. Preliminary comparisons with previous versions have shown better quality and superiority of incident dark field in detecting more vessels. PtcO2 measurements have been applied mainly to detect a peripheral low-flow state in circulatory failure using the oxygen challenge test. Altered lung function might have an influence on PtcO2, and thus affect the oxygen challenge test.
SUMMARY: The latest developments of noninvasive optical monitoring and transcutaneous oximetry technologies have helped early identification of septic patients at high risk for microcirculatory failure and could allow more targeted interventions in shock.