Prolonged observation time reveals temporal fluctuations in the sublingual microcirculation in pigs given arginine vasopressin

Imaging sublingual microcirculatory perfusion in pediatric patients receiving procedural sedation with propofol: A pilot study

Objective

Procedural sedation with propofol is widely used in the pediatric population. A well‐known side effect of propofol is a decrease in peripheral vascular resistance resulting in hypotension, but little is known about the effects on microcirculation in humans. We aimed to evaluate the effects of propofol on the sublingual microcirculatory perfusion by continuous video imaging in pediatric patients undergoing procedural sedation.

Methods

Patients admitted to the Pediatric Intensive Care Unit for procedural sedation were recruited. Oral microcirculation was measured employing a continuous monitoring strategy with incident dark‐field illumination imaging. Measurements were obtained before and 3 minutes after propofol induction. Total and perfused vessel densities, proportion of perfused vessels, microvascular flow index, blood vessel diameter (Ø_bv), and systemic hemodynamics were analyzed.

Results

Continuous measurements were achieved in seven patients. Three minutes after propofol induction mean arterial pressure decreased (P = 0.028) and total and perfused vessel densities increased by 12% (P = 0.018) and 16% (P = 0.018), respectively. MFI was unaltered and mean Ø_bv increased but not significantly.

Conclusions

Propofol induction induces a reduction in mean arterial pressure and a rise in sublingual microvascular perfusion. The observed effects of propofol on the sublingual microcirculation may be due to a decrease in microvascular resistance.

Microcirculatory assessment of patients under VA-ECMO

Background

Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is an effective technique for providing emergency mechanical circulatory support for patients with cardiogenic shock. VA-ECMO enables a rapid restoration of global systemic organ perfusion, but it has not been found to always show a parallel improvement in the microcirculation. We hypothesized in this study that the response of the microcirculation to the initiation of VA-ECMO might identify patients with increased chances of intensive care unit (ICU) survival.

Methods

Twenty-four patients were included in this study. Sublingual microcirculation measurements were performed using the CytoCam-IDF (incident dark field) imaging device. Microcirculatory measurements were performed at baseline, after VA-ECMO insertion (T1), 48–72 h after initiation of VA-ECMO (T2), 5–6 days after (T3), 9–10 days after (T4), and within 24 h of VA-ECMO removal.

Results

Of the 24 patients included in the study population, 15 survived and 9 died while on VA-ECMO. There was no significant difference between the systemic global hemodynamic variables at initiation of VA-ECMO between the survivors and non-survivors. There was, however, a significant difference in the microcirculatory parameters of both small and large vessels at all time points between the survivors and non-survivors. Perfused vessel density (PVD) at baseline (survivor versus non-survivor, 19.21 versus 13.78 mm/mm², p = 0.001) was able to predict ICU survival on initiation of VA-ECMO; the area under the receiver operating characteristic curve (ROC) was 0.908 (95 % confidence interval 0.772–1.0).

Conclusion

PVD of the sublingual microcirculation at initiation of VA-ECMO can be used to predict ICU mortality in patients with cardiogenic shock.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-016-1519-7) contains supplementary material, which is available to authorized users.