Objectives: To assess whether an increase in mean arterial pressure in patients with septic shock and previous systemic arterial hypertension changes microcirculatory and systemic hemodynamic variables compared with patients without arterial hypertension (control). Design: Prospective, nonblinded, interventional study. Setting: Three ICUs in two teaching hospitals. Patients: After informed consent, we included patients older than 18 years with septic shock for at least 6 hours, sedated, and under mechanical ventilation. We paired patients with and without arterial hypertension by age. Interventions: After obtaining systemic and microcirculation baseline hemodynamic variables (time 0), we increased noradrenaline dose to elevate mean arterial pressure up to 85–90 mm Hg before collecting a new set of measurements (time 1). Measurements and Main Results: We included 40 patients (20 in each group). There was no significant difference in age between the groups. After the rise in mean arterial pressure, there was a significant increase in cardiac index and a slight but significant reduction in lactate in both groups. We observed a significant improvement in the proportion of perfused vessels (control: 57.2 ± 14% to 66 ± 14.8%; arterial hypertension: 61.4 ± 12.3% to 70.8 ± 7.1%; groups: p = 0.29; T0 and T1: p < 0.001; group and time interaction: p = 0.85); perfused vessels density (control: 15.6 ± 4 mm/mm2 to 18.6 ± 4.5 mm/mm2; arterial hypertension: 16.4 ± 3.5 mm/mm2 to 19.1 ± 3 mm/mm2; groups: p = 0.51; T0 and T1: p < 0.001; group and time interaction: p = 0.70), and microcirculatory flow index (control: 2.1 ± 0.6 to 2.4 ± 0.6; arterial hypertension: 2.1 ± 0.5 to 2.6 ± 0.2; groups: p = 0.71; T0 and T1: p = 0.002; group and time interaction: p = 0.45) in both groups. Conclusions: Increasing mean arterial pressure with noradrenaline in septic shock patients improves density and flow in small vessels of sublingual microcirculation. However, this improvement occurs both in patients with previous arterial hypertension and in those without arterial hypertension.

BackgroundActive mobilization is not possible in patients under deep sedation and unable to follow commands. In this scenario, passive therapy is an interesting alternative. However, in patients with septic shock, passive mobilization may have risks related to increased oxygen consumption. Our objective was to evaluate the impact of passive mobilization on sublingual microcirculation and systemic hemodynamics in patients with septic shock.MethodsWe included patients who were older than 18 years, who presented with septic shock, and who were under sedation and mechanical ventilation. Passive exercise was applied for 20 min with 30 repetitions per minute. Systemic hemodynamic and microcirculatory variables were compared before (T0) and up to 10 min after (T1) passive exercise. p values <0.05 were considered significant.ResultsWe included 35 patients (median age [IQR 25–75%]: 68 [49.0–78.0] years; mean (±SD) Simplified Acute Physiologic Score (SAPS) 3 score: 66.7 ± 12.1; median [IQR 25–75%] Sequential Organ Failure Assessment (SOFA) score: 9 [7.0–12.0]). After passive mobilization, there was a slight but significant increase in proportion of perfused vessels (PPV) (T0 [IQR 25–75%]: 78.2 [70.9–81.9%]; T1 [IQR 25–75%]: 80.0 [75.2–85.1] %; p = 0.029), without any change in other microcirculatory variables. There was a reduction in heart rate (HR) (T0 (mean ± SD): 95.6 ± 22.0 bpm; T1 (mean ± SD): 93.8 ± 22.0 bpm; p < 0.040) and body temperature (T0 (mean ± SD): 36.9 ± 1.1 °C; T1 (mean ± SD): 36.7 ± 1.2 °C; p < 0.002) with no change in other systemic hemodynamic variables. There was no significant correlation between PPV variation and HR (r = −0.010, p = 0.955), cardiac index (r = 0.218, p = 0.215) or mean arterial pressure (r = 0.276, p = 0.109) variation.ConclusionsIn patients with septic shock after the initial phase of hemodynamic resuscitation, passive exercise is not associated with relevant changes in sublingual microcirculation or systemic hemodynamics.Electronic supplementary materialThe online version of this article (doi:10.1186/s13613-017-0318-x) contains supplementary material, which is available to authorized users.