Noninvasive examination of the venous system in the leg: presclerotherapy evaluation

Sclerotherapy of varicose veins and telangiectasia should be preceded by a directed medical history and physical examination. Factors including the presence of significant venous disease should prompt a more extensive evaluation. Of the physical examination techniques and noninvasive technologies available, Doppler ultrasound provides the most pertinent information, but the potential uses of each method are described.     

Effect of long-term sympathectomy on the arterial wall in rabbits and rats

The effect of chemical sympathectomy with 6-hydroxydopamine (6-OH-DA) on collagen formation in the aortic wall was investigated in rabbits and rats. Eight weeks after 6-OH-DA treatment of rabbits, there was a significant increase an collagen content in aortas and histologic changes in the elastic elements within the media. The possibility of a direct effect of 6-OH-DA on connective tissue formation was investigated in a subsequent experiment in rats. The rates of collagen synthesis and prolyl hydroxylase activity (PHA) were determined in aortas and in the fibrotic granuloma around subcutaneously implanted polyvinylalcohol sponges. Rates of collagen synthesis and PHA were significantly increased in the aortas of 6-OH-DA treated rats, but not in fibrotic granuloma, confirming the changes seen in the aorta of rabbits and suggesting that 6-OH-DA does not directly affect collagen synthesis. We conclude that the sympathetic nervous system influences the metabolic activity of the aorta. Our data indicate that when the aortic wall is deprived of adrenergic nervous stimulation, changes occur which resemble those seen in natural aging of the aorta. It is plausible to assume that such a metabolic derangement in the vessel wall will make these vessels more vulnerable to additional stresses.     

‘This neo-natal ménage à trois’: British media framing of transnational surrogacy

Background: Media framing can influence people’s perceptions of social changes in family building, and has the potential to influence their future actions. Objectives: to analyse the type of framing and construction used in British newsprint of transnational commercial surrogacy. Methods: UK newspapers were searched using the search engine Lexis-Nexis. One hundred and ninety-seven articles were analysed. Content analysis was undertaken to identify the use of gain, loss, neutral, alarm and vulnerability frames, as well as type of construction (i.e. ethical, social, legal, financial and medical). Four researchers independently analysed articles using a coding strategy. Results: Differences between serious (mainly legal, financial), middle-market (legal) and tabloid (social, financial) newspapers were found. There were three main foci; buying babies – affordable only to those wealthy enough to pay for it; the legal complications of transnational surrogacy – reporting a sense of the legal system lagging behind this practice; and gay families – repeatedly questioning their suitability as parents – demonstrating a prevailing heterosexual stereotype about reproduction and parenting. Conclusions: Stereotyping was prevalent and the welfare of children and medical aspects of transnational surrogacy were minimally addressed, indicating the media selectively influences its readership.     

Pre- and postcapillary resistances in cat mesentery

The hemodynamic behavior of the isolated autoperfused intestinal loop (including mesenteric segment) of the cat was studied in terms of inflow and outflow pressures (BP and VP), arteriolar and venular pressures (P_a and P_v), and blood flow (Q). The regional vascular resistance [$\text{RR =}\text{(BP ? VP)}\text{Q}$] was subdivided into a precapillary resistance [$\text{P}{}_{\mathrm{<mtext>r</mtext>}}\text{R =}\text{(BP ? P}{}_{\mathrm{a}}\text{)}\text{Q}$], capillary resistance [$\text{CR =}\text{(P}{}_{\mathrm{a}}\text{? P}{}_{\mathrm{v}}\text{)}\text{Q}$], and postcapillary resistance [$\text{P}{}_{\mathrm{<mtext>s</mtext>}}\text{R =}\text{(P}{}_{\mathrm{v}}\text{? VP)}\text{Q}$]. With normal perfusion pressure it was found that: P_rR = 68%, P_sR = 20.5% and CR = 11.5%. Two different responses were noted when perfusion pressure was lowered to 20mm Hg. In the first group, precapillary resistance fell significantly, whereas postcapillary resistance did not change. In the second group, the regional resistance increased due to the increase in precapillary resistance and a significantly greater increase in postcapillary resistance. The regulatory mechanism in the first group is based on local readjustment of the precapillary vasculature with no participation of postcapillary vessels. The second group of responses appears to be related to completely dilated vessels, where regulation is achieved by increasing postcapillary resistance in an attempt to maintain the capillary pressure and homeostatic balance.     

Quantified duplex augmentation in healthy subjects and patients with venous disease: San Diego population study

OBJECTIVE: This study was undertaken to determine the quantitative augmentation response in several veins examined in a cohort assembled to permit comparisons by sex, age, and ethnicity, under normal conditions and in the presence of obstruction, with and without trophic changes. METHOD: The common femoral vein, superficial femoral vein, sapheno-femoral junction, popliteal vein, sapheno-popliteal junction, and posterior tibial vein were studied with duplex ultrasonographic scanning. Augmentation response was elicited with use of an automated cuff inflator. Mean level of each response was analyzed according to patient sex, age, and ethnicity, each adjusted for the other two. Normal values were compared with those obtained from legs with venous obstructive disease, with or without signs of trophic changes. RESULTS: Decreased augmentation response was noted only in the sapheno-femoral junction and sapheno-popliteal junction, and was smaller in women. Augmentation response was slightly increased in the oldest age group (>70 years) in the common femoral vein, superficial femoral vein, popliteal vein, and posterior tibial vein. The highest augmentation response was found in Asian subjects, in the common and superficial femoral veins and the sapheno-femoral and sapheno-popliteal junctions; and the smallest augmentation response was found in African American subjects, in these same veins and junctions. Differences in vein diameters may explain these findings, ie, smaller diameters in Asians and larger diameters in African Americans. Most important, compared with normal values, augmentation response was decreased in legs with venous obstructive disease only when trophic changes were present. CONCLUSION: Like quantification of reflux, quantitative evaluation of the augmentation response may help in diagnosis of venous obstructive disease when trophic changes are present.