Quantitative assessment of the microcirculation in healthy volunteers and in patients with septic shock.

OBJECTIVE: The microcirculation of septic patients has been characterized only semiquantitatively. Our goal was to characterize the sublingual microcirculation in healthy volunteers and patients with septic shock quantitatively. Our hypotheses were that 1) hyperdynamic blood flow is absent in septic shock; 2) nonsurvivors show more severe alterations than survivors; and 3) quantitative and semiquantitative microcirculatory parameters have a similar performance. DESIGN: Prospective, observational study. SETTING: Teaching intensive care unit in a university-affiliated hospital. SUBJECTS: Twenty-five normal volunteers and 25 patients with septic shock. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The sublingual microcirculation was evaluated by means of sidestream dark field imaging. Semiquantitative and quantitative microcirculatory parameters were determined through the use of applied software. Septic patients showed decreased perfused capillary density (13.2±4.4 mm/mm² vs. 16.6±1.6 mm/mm²), proportion of perfused capillaries (0.78±0.23 vs. 1.00±0.01), microvascular flow index (2.15±0.61 vs. 2.97±0.03), and red blood cell velocity (830±183 µm/sec vs. 1332±187 µm/sec) along with increased heterogeneity flow index (1.64±1.14 vs. 0.25±0.19) compared with controls. No differences were found in total capillary density (16.9±2.2 vs. 16.7±1.6). Only 4% of capillaries analyzed showed red blood cell velocities>75th percentile of the velocities of the normal volunteers. The nonsurvivors exhibited decreased perfused capillary density, proportion of perfused capillaries, and microvascular flow index along with increased heterogeneity flow index compared with the survivors. The correlations between microvascular flow index and proportion of perfused capillaries, total capillary density and number of grid-crossing capillaries, and red blood cell velocities and microvascular flow index gave high R values (0.92, 0.65, and 0.52, respectively; p<.0001 for all). CONCLUSIONS: The main characteristics of sublingual microcirculation in patients with septic shock are hypoperfusion and increased flow heterogeneity. Hyperdynamic microvascular blood flow was not found. Nonsurvivors showed more severe alterations than survivors. Quantitative and semiquantitative microcirculatory variables displayed similar behaviors.

Heterogeneity of dietary profiles in highly sedentary young Guadeloupean women.

OBJECTIVE: The aim was to examine the relationship between physical activity pattern and dietary profile. Although some clustering of the variables related to these major determinants of cardiovascular risk has been demonstrated, they have not been extensively studied together. PARTICIPANTS, DESIGN, AND SETTING: Two hundred two female university students from the main Guadeloupe (French West Indies) campus participated. They self-administered a validated Food Frequency Questionnaire and the 1-yr recall Modifiable Activity Questionnaire. Principal-component analysis was performed on the scores and the variables related to the physical activity pattern and dietary profile. RESULTS: A model including 10 variables explained 84.9% of the total variance. The physical activity pattern was not associated with the dietary profile, apart from fruit intake. The physical activity level was homogeneously low (median 1.58, first and last quartile cutoffs 1.54 and 1.66, respectively). There was no correlation between the physical activity level and the Food Frequency Questionnaire score (r=-.005). CONCLUSIONS: The absence of a strong relationship between the food and physical activity profiles is interpreted as a possible reflection of a dysregulation of the quality of food intake in this population with a sedentary lifestyle.