Anatomic and physiologic changes in lower extremity venous hemodynamics associated with pregnancy

AbstractPurpose: The purpose of this study was to describe the physiologic effects of pregnancy on lower extremity venous hemodynamics.Methods: Eight pregnant women, six with no known venous disease (NVD) and two with documented deep venous obstruction (DVO), were identified in the first trimester (TM) and studied monthly until delivery and once postpartum (pp) by air plethysmography and duplex scan.Results: None of six women in the NVD group (12 extremities) had obstruction or elevated ambulatory venous pressures as estimated by air plethysmography. In addition, despite significant increases in common femoral vein and saphenofemoral junction diameters, no woman in the NVD group had reflux by either test. Venous filling index increased significantly during pregnancy and decreased significantly pp, but all values remained within the normal range (0.55 ± 0.2 ml/sec first TM, 1.01 ± 0.38 ml/sec late third TM, 0.58 ± 0.08 ml/sec pp; p < 0.03 both comparisons). Common femoral vein diameters increased and decreased in similar fashion (0.99 ± 0.25 cm first TM, 1.21 ± 0.25 cm late third TM, 0.80 ± 0.11 cm pp; p < 0.0005 first vs late third TM, p < 0.005 late third TM vs pp). Saphenofemoral junction vein diameters similarly increased and decreased in size (0.46 ± 0.07 cm first TM, 0.68 ± 0.19 cm late third TM, 0.50 ± 0.10 cm pp; p < 0.01 first vs late third TM, p < 0.03 late third TM vs pp). Neither of the two women in the DVO group showed deterioration of outflow fraction or venous filling index as pregnancy progressed, and neither had thromboembolic complications despite moderate to severe preexisting obstruction. Both women in the DVO group delivered uneventfully. No woman in either group developed varicose veins.Conclusion: Pregnancy-induced changes in lower extremity venous hemodynamics in the NVD and DVO groups were detected but were small. Hormonal or other systemic factors must play a significant role in the development of postpartum varicose veins. (J Vasc Surg 1996;24:763-7.

Mycotic renal artery degeneration and systemic sepsis caused by infected renal artery stent

AbstractA case of Staphylococcus aureus renal artery stent infection was studied. Fourteen days after the procedure, the patient had a fever, hypotension, and an elevated white blood cell (WBC) count. Blood cultures were positive for S aureus on admission and during the patient's hospitalization, despite intravenous vancomycin therapy. Evaluation included serial CT scans, revealing increasing persistent inflammation with development of multiple renal intraparenchymal abscesses, and arteriography, showing marked degeneration of the renal artery. Therapy required resection of the renal artery/stent and nephrectomy. This case confirms the severe nature of S aureus stent infection; we recommend prophylactic antibiotics before these procedures, as well as expeditious evaluation and consideration for aggressive surgical therapy if this complication is suspected. (J Vasc Surg 1998;28:547-50.

Introduction of Genetically Engineered Organisms - Draft Programmatic Environmental Impact Statement—July 2007

The U.S. Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS) regulates the environmental introduction of genetically engineered (GE) organisms, including crop and noncrop plants, vertebrate and invertebrate animals, and micro-organisms. APHIS regulations are grounded in the most up-to-date science and are designed to provide a level of oversight appropriate for the safe introduction of GE organisms. APHIS is considering whether revisions to its regulations are necessary. One purpose of such revisions would be to address current and future technological trends resulting in GE plants with which the agency is less familiar, such as plants with environmental stress tolerance or enhanced nutrition, and plants engineered for new purposes such as biofuels or for production of pharmaceutical or industrial compounds. Additionally, the regulations would be revised to ensure a high level of environmental protection, to create regulatory processes that are transparent to stakeholders and the public, to consider the efficient use of agency resources, to ensure that the level of oversight is commensurate with the risk, and to ensure conformity with obligations under international treaties and agreements, such as World Trade Organization (WTO) agreements. To this end, this draft environmental impact statement (DEIS) was prepared to provide agency decisionmakers with a full range of regulatory alternatives and assist them in selecting a preferred alternative

Defective lung macrophage function in lung cancer +/- chronic obstructive pulmonary disease (COPD/emphysema)-mediated by cancer cell production of PGE2?

In chronic obstructive pulmonary disease (COPD/emphysema) we have shown a reduced ability of lung and alveolar (AM) macrophages to phagocytose apoptotic cells (defective ‘efferocytosis’), associated with evidence of secondary cellular necrosis and a resultant inflammatory response in the airway. It is unknown whether this defect is present in cancer (no COPD) and if so, whether this results from soluble mediators produced by cancer cells. We investigated efferocytosis in AM (26 controls, 15 healthy smokers, 37 COPD, 20 COPD+ non small cell lung cancer (NSCLC) and 8 patients with NSCLC without COPD) and tumor and tumor-free lung tissue macrophages (21 NSCLC with/13 without COPD). To investigate the effects of soluble mediators produced by lung cancer cells we then treated AM or U937 macrophages with cancer cell line supernatant and assessed their efferocytosis ability. We qualitatively identified Arachidonic Acid (AA) metabolites in cancer cells by LC-ESI-MSMS, and assessed the effects of COX inhibition (using indomethacin) on efferocytosis. Decreased efferocytosis was noted in all cancer/COPD groups in all compartments. Conditioned media from cancer cell cultures decreased the efferocytosis ability of both AM and U937 macrophages with the most pronounced effects occurring with supernatant from SCLC (an aggressive lung cancer type). AA metabolites identified in cancer cells included PGE2. The inhibitory effect of PGE2 on efferocytosis, and the involvement of the COX-2 pathway were shown. Efferocytosis is decreased in COPD/emphysema and lung cancer; the latter at least partially a result of inhibition by soluble mediators produced by cancer cells that include PGE2.Francis C. Dehle, Violet R. Mukaro, Craig Jurisevic, David Moffat, Jessica Ahern, Greg Hodge, Hubertus Jersmann, Paul N. Reynolds, Sandra Hodg

Pelvic congestion syndrome: Early clinical results after transcatheter ovarian vein embolization

AbstractPurpose: This case series describes the early radiographic and clinical results of attempted transcatheter ovarian vein (OV) embolization in 11 women with symptoms that were suggestive of the pelvic congestion syndrome (PCS). Methods: Eleven women (mean age, 33.1 years) who were multiparous were referred for lower extremity or vulvar varicosities (n = 8) or for tubo-ovarian varicosities (n = 3). After a clinical diagnosis of PCS was established, the women underwent ovarian (n = 5) or ovarian and iliac vein (n = 6) venography. Enlarged or incompetent OVs were embolized with 0.035-inch stainless steel coils or with 0.018-inch platinum microcoils and absorbable gelatin sponge. Incompetent tributaries to hypogastric veins were embolized as well (n = l). Symptoms before embolization and after embolization were recorded with a standard questionnaire, and the post-embolization symptoms were expressed as individual and overall percent relief. Results: Nine of the 11 women underwent embolization. Embolization of both OVs (n = 4), of the left OV alone (n = 4), or of a left obturator vein that communicated with vulvar varices (n = l) was performed. Eight of the 9 women (88.9%) had more than 80% immediate relief. Overall and individual symptom relief varied from 40% to 100% at the mean 13.4-month follow-up. One woman with variant anatomy and one woman with evidence of prior left OV thrombosis were not treated. There were no major complications. Two women had a mild to moderate return of the symptoms at 6 and 22 months. Conclusions: Transcatheter embolization provides excellent initial and variable midterm relief in women with typical PCS symptoms and with OV or OV and internal iliac (hypogastric) tributary vein incompetence. This interventional technique may replace or complement the traditional surgical approaches to this rarely recognized and poorly understood disease. (J Vasc Surg 1998;28:862-8.

Physiological changes in venous hemodynamics associated with elective fasciotomy

It has been postulated that lower extremity fasciotomy may disrupt the calf musculovenous pump and predisposes to development of chronic venous insufficiency (CVI). However, studies based on trauma patients who undergo emergent fasciotomy are confounded by the possibility of concomitant vascular and soft tissue injury and use historical controls. This is a prospective study that evaluates venous hemodynamics in young patients undergoing elective fasciotomy for chronic exertional compartment syndrome (CECS), eliminating the problems associated with retrospective study of trauma patients. CECS was diagnosed by history and, when indicated, measurement of compartment pressures. Prior to elective two- or four-compartment fasciotomy, each patient underwent lower extremity air plethysmography (APG) and colorflow duplex ultrasonography. These studies were repeated a minimum of 6 weeks postoperatively. Fifteen patients who had fasciotomies for CECS were studied; two of these patients had bilateral fasciotomies for a total of 17 limbs. There were 13 male and two female patients (average age 31.2 years). APG and colorflow duplex were performed an average of 12 weeks after fasciotomy. Outflow fraction, venous volume, and ejection volume showed no significant changes postoperatively. However, the venous filling index (VFI) increased (0.9 ± 0.1 vs. 1.1 ± 0.1 mL/sec; p \u3c 0.05, paired t-test), the ejection fraction tended to decrease (59 ± 4% vs. 52 ± 2%; p \u3c 0.08, paired t-test), and the residual volume fraction (RVF) increased (26 ± 3% vs. 36 ± 5%; p \u3c 0.05, paired t-test). There were no patients with evidence of deep venous reflux. Two extremities with preoperative greater saphenous vein (GSV) reflux did not worsen, and three extremities developed new GSV reflux following fasciotomy, although VFI remained normal in each extremity. Elective fasciotomy for CECS does not lead to significant venous reflux but likely does diminish calf muscle pump function and increases RVF moderately in young adult patients. With longer follow-up this diminished calf muscle pump function may increase the risk of CVI. © Annals of Vascular Surgery Inc