tailieunhanh - Critical Care Obstetrics part 31

Critical Care Obstetrics part 31 provides expert clinical guidance throughout on how you can maximize the chances of your patient and her baby surviving trauma. In this stimulating text, internationally recognized experts guide you through the most challenging situations you as an obstetrician are likely to face, enabling you to skillfully:Recognize conditions early-on which might prove life threatening, Implement immediate life-saving treatments in emergency situations, Maximize the survival prospects of both the mother and her fetus | Thromboembolic Disease a clot in the iliac vessels as well as pelvic thrombophlebitis or ovarian vein thrombosis. The use of computed tomography CT or magnetic resonance imaging MRI however may be more helpful in these latter conditions. MRI is now being used more frequently for the diagnosis of DVT in the pregnant patient and may eventually become the imaging modality of choice 63 . Ascending venography Venography is the gold standard for the diagnosis of DVT in pregnancy. If the clinical suspicion is high and non-invasive tests are negative limited venography with abdominal shielding should be done. With the patient at an approximate 40 incline and bearing weight on her unaffected leg radiographic contrast dye is injected into a dorsal vein of the involved foot. This position allows for the gradual and complete filling of the leg veins without layering of the dye and reduces the likelihood of a falsepositive test. Nonetheless false-positive tests may result from poor technique poor choice of injection site contraction of the leg muscles or extravascular pathology such as a Baker s popliteal cyst hematoma cellulites edema or muscle rupture. In addition the larger diameter of the deep femoral and iliac veins can lead to incomplete filling with the dye and unreliable results. Positive identification of a thrombus requires visualization of a well-defined filling defect in more than one radiography view Figure . Suggestive signs of a DVT include abrupt termination of a vessel absence of opacification or diversion of blood flow. Unlike ultrasonography and Doppler procedures venography is associated with significant side effects. Twenty-four percent of patients will experience minor side effects of muscle pain leg swelling tenderness or erythema 64 . Five percent will develop an allergic reaction. There exists a 1-2 risk of thrombophlebitis after the procedure. These side effects can be reduced by 70 by lowering the concentration of contrast medium 61 . Using a .