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Background. In adults severely disturbed microcirculatory flow can be observed by Orthogonal Polarized Spectral (OPS) imaging techniques during sepsis. Therefore we set out to assess for microcirculatory changes in term newborns with suspected early onset infection using OPS. Methods. OPS images were obtained prospectively from the vascular bed of the ear conch and upper arm of 47 newborns on their 1st, 2nd, and 3rd day of life. OPS sequences were analyzed semiquantitatively offline and blinded to clinical status of the infant. Flow in vessels was classified as continuous or noncontinuous flow and given as proportion of total vessels per image as in the studies in adults. Results. The proportion of vessels with continuous flow was significantly lower in the infants with infection (69% [56-81] versus 90% [87-94] (P = 0.0003)). None of the infants with infection was in shock or severely septic. Conclusion. In term neonates the microcirculatory flow is impaired in a large proportion of vessels even in mild to moderate infection. These changes can be observed at the onset of disease at the external ear, an optimal site for microcirculatory measurements in term infants.

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OBJECTIVES: To assess potential effects of a hemodynamically significant persistent ductus arteriosus (sPDA) in the skin microcirculation in preterm neonates. STUDY DESIGN: In 25 patients (<32 weeks of gestation; birth weight <1250 g) with sPDA (n = 13) or no significant PDA (non-sPDA; n = 12) functional vessel density and vessel diameters were investigated prospectively. Sidestream dark field imaging was performed in the skin of both arms from the third day of life until PDA closure or until day 7 or 8 for the non-sPDA group. RESULTS: Before PDA treatment, functional vessel density was significantly lower in the sPDA group compared with the non-sPDA group. In the sPDA group, there were significantly fewer large vessels (diameter >20 microm) and significantly more small vessels (diameter <10 microm). After successful PDA treatment, these differences disappeared. In both groups, functional vessel density differed significantly between the left and right arm, persisting even after successful treatment. Regression analysis showed an inverse linear correlation between the hemodynamic echocardiographic findings and functional vessel density (P <.005). CONCLUSION: sPDA causes major changes in the microcirculation of premature neonates; functional vessel density is reduced, with a shift in perfusion from larger toward smaller vessels. The redistribution of flow might be a compensatory mechanism to preserve physiologic metabolism.

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In adults with severe sepsis, the disturbances of the sublingual microcirculation can be quantified with orthogonal polarization spectral imaging. We investigated the cutaneous microcirculation of preterm infants with proven infection (PosInf) and with suspected but unproven infection (NegInf). In 25 infants, orthogonal polarization spectral images were obtained daily, videos of the images were blinded, and analyzed off-line. Functional small vessel density (FSVD) was prospectively calculated from day 3 to day 30 of life. There were 17 episodes of proven and nine episodes of suspected but unproven nosocomial late onset infection. Four infants remained healthy. The data were analyzed for the 5 d before the start of antibiotics (day -5 until day -1). FSVD varied widely, but in the PosInf-group, we found a 10% decline from day -5 to day -1 (p = 0.013). There was no significant change over time in the NegInf-group (p = 0.58). Thus, in infants with proven infection, FSVD decreases already 1 d before changes in laboratory parameters. However, these changes in FSVD during infection are not represented by absolute values, but must be identified by daily intraindividual observation.

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BACKGROUND: The aim of this study was to determine the effects of HIV type-1 (HIV-1) infection and antiretroviral therapy (ART) on placental mitochondria. METHODS: HIV-1-infected pregnant women and HIV-1-uninfected controls were enrolled prospectively. Placental mitochondrial DNA (mtDNA) copy numbers were determined by quantitative PCR, subunits II and IV of cytochrome c oxidase (COX) were quantified by western blot and mitochondrial ultrastructure was evaluated by electron microscopy. Venous blood lactate was measured in newborns. RESULTS: In total, 45 HIV-1-infected pregnant women on ART and 32 controls were included. Mean +/-sd mtDNA copy numbers were significantly reduced in ART and HIV-1-exposed placentas (240 +/-118 copies/cell) in comparison with controls (686 +/-842 copies/cell; P<0.001). The mean COX II/IV ratio was 48% lower in the investigational group compared with controls (P<0.001). There was no evidence of severe ultrastructural damage within mitochondria of HIV-1-infected ART-exposed placentas. Although lactate levels between newborns did not differ, they were negatively correlated with placental mtDNA levels. There was no clear association between mitochondrial parameters and a particular nucleoside reverse transcriptase inhibitor (NRTI), the number of NRTIs or time of NRTI exposure. CONCLUSIONS: Placental tissue of HIV-1-infected ART-exposed pregnancies shows evidence of mtDNA depletion with secondary respiratory chain compromise. The clinical effects of this finding warrant further investigation.

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Changes in microcirculation have been recognized as central to many disease processes. The aim of this study was to evaluate factors, which influence the microcirculation of the skin during the first month of life in premature infants. Red blood cell (RBC) velocity, vessel diameter, and functional small vessel density (FSVD) were measured daily for the first 30 d on the upper arm in preterm infants with gestational age <30 wk. Orthogonal polarization spectral (OPS) images were analyzed off-line with the Capi- Scope-Image program. In 25 infants, FSVD decreased significantly from week 1 (mean +/- SD 236 +/- 33 cm/cm2) to week 4 (207 +/- 30 cm/cm2) and correlated directly with Hb levels and incubator temperature. Vessel diameters and RBC velocity did not change significantly, nor did clinical parameters such as blood pressure, heart rate or body temperature. Microvascular parameters were not dependent on gestational or postnatal age. The microcirculation of the skin might be an easily accessible window to obtain better understanding of circulatory changes in the postnatal period. Our data are essential as basis for further studies in this field. Hb levels and possible incubator temperatures have a substantial influence on functional small vessel density and therefore need to be taken in account.

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