Blood flow velocity comparison in the eye capillaries and postcapillary venules between normal pregnant and non-pregnant women.

BACKGROUND: There is no consensus on how much and at what diameters the blood flow velocity changes in the female microcirculation during normal pregnancy. METHODS: A non-contact, digital slit-lamp biomicroscopy system was used to measure axial blood velocity (Vax) and diameter (D) in the conjunctival microcirculation of 28 normal non-pregnant women (Control Group), 17 women in the first semester of their normal pregnancy (Group 1) and 16 women in the third trimester of their normal pregnancy (Group 2). Blood volume flow (Q) was estimated from Vax and D. Microvessels were classified as "capillaries" (CAP) with D < 9 µm, "postcapillary venules of size 1" (PC1) with 9 ≤ D < 14 µm and "postcapillary venules of size 2" (PC2) with 14 ≤ D ≤ 24 µm. RESULTS: The women groups did not differ significantly in age, diastolic and systolic pressure and diameter of each size. Taking as baseline the capillary Vax of 0.51 mm/s of the Control Group, there was a statistically significant (p < 0.001) increase to 0.74 mm/s (45%) in Group 1 and to 0.95 mm/s (86%) in Group 2. This significant Vax increase in capillaries (CAP) was a consistent finding irrespective of the exact vessel size cut-off value for discriminating CAP from PC1. There was no statistical difference in Vax among groups at postcapillary venules of size 2 (PC2). Statistical conclusions for blood volume flows were similar to velocities. CONCLUSIONS: Normal pregnancy increases significantly axial blood velocity (Vax) in capillaries (CAP) with diameter <9 µm.

Predicting short-term mortality in patients with pulmonary embolism: a simple model.

BACKGROUND: The aim of the present study was to develop a simple prognostic rule that could classify patients with pulmonary embolism (PE) into categories of increased risk of 30-day mortality. METHODS: One hundred patients with PE were enrolled. Clinical and laboratory findings were recorded on admission for each patient. Differences between groups' survival and death were tested, and the association with the 30-day mortality was determined. RESULTS: Three variables had a significant effect on survival: age, Charlson index and the alveolar to arterial (A-a) gradient. A receiver operating characteristic analysis was performed, and the cut-off points used for the comparison of survival were 67 years of age, A-a gradient over 52.8 mm Hg and Charlson index over 2. By combining these variables, a score was established for distinguishing patients with PE who are at high risk. This score was also validated in a group of 30 consecutive patients admitted to the hospital for PE Additionally, a tree method was applied and showed that for patients with a history of diabetes and Charlson index >3, the expected outcome is death. CONCLUSIONS: The results of this study suggest that patients with PE could be stratified into categories of increasing risk of 30-day mortality using a simple score based only on routinely available variables. Future studies are needed to validate our prognostic model in a large cohort of patients with PE.