Evaluation of the sublingual microcirculation in cardiogenic shock

Orthogonal polarized spectral imaging- and sidestream darkfield-technique have enabled visual evaluation of the microcirculation. Different investigators described microcirculatory alterations, especially in surgical patients suffering from septic shock. We investigated the sublingual microcirculation in non-surgical patients admitted to our medical, intensive care unit (ICU).

In 24 severely ill (APACHE-II Score: 27.8+/-11.3), intubated patients admitted to our ICU the sublingual microcirculation was recorded with a handheld intravital microscope. Sublingual vessels were categorized according to their size (small: 10-25 microm; medium: 26-50 microm; large: 51-100 microm) and the flow in semiquantitative categories (0: no flow; 1: intermittent flow; 2: sluggish flow; 3: continuous flow).

Patients with cardiogenic shock (n=7) had lower microflow compared with patients without cardiogenic shock (small p<0.001, medium p<0.001, large p=0.003). Several other diseases, including diabetes and arterial hypertension, age, gender, had no influence. In general, patients with a flow less than 3 in the small vessels showed higher arterial blood lactate levels (p=0.043) compared to continuous flow.

A consequence of cardiogenic shock is the impairment of microcirculation with organ hypoperfusion. We observed that cardiac output is correlated to disturbance in microflow in the smallest vessels. On-line evaluation of microcirculation in vivo may be a valid tool for optimizing therapeutic measures in high risk patients. Additional online material may be found at: http://www.kim1.uniklinik-jena.de/Microcirculation.html.