A 34-year-old woman just delivered a 4100-g boy after a 15-hour labor, including a 21/2-hour second stage. During the repair of a midline episiotomy, there is a marked increase in the amount of vaginal bleeding.Which of the following is the most common cause of immediate postpartum hemorrhage?
Answer(s): B
The main mechanism by which hemostasis is achieved following delivery is contraction of the myometrium to compress the uterine vessels that had been supplying the placenta. Lack of effective myometrial contraction (i.e., uterine atony) is the major cause of postpartum hemorrhage. If the uterus is found to be firmly contracted, then other factors, such as cervical or vaginal lacerations or a coagulopathy, must be sought.
A 34-year-old woman just delivered a 4100-g boy after a 15-hour labor, including a 21/2-hour second stage. During the repair of a midline episiotomy, there is a marked increase in the amount of vaginal bleeding.Which of the following is the best immediate management of the probable cause of this postpartum hemorrhage?
Answer(s): A
Immediate management is bimanual massage and compression of the uterine fundus by placing one fist into the anterior vaginal fornix and the other hand abdominally posterior to the uterus. The uterine massage is often enough to cause myometrial contractions and slowing of the bleeding. Oxytocin or an ergot alkaloid (e.g., methylergonovine) should then be administered if bimanual massage of the uterus is ineffective.Insertion of a gauze pack is never indicated because it is rarely effective. It may actually worsen the bleeding by preventing contraction of the myometrium. Persistent bleeding from the uterus despite these measures may indicate uterine rupture, retained placental fragments, or placenta accreta. If a careful curettage of the uterine lining fails to remove any placental fragments and decrease uterine bleeding, hypogastric artery ligation or a hysterectomy must be considered.
A 55-year-old woman has a bloody discharge from her left breast. A mammogram discloses a cluster of microcalcifications 3 cm beneath her left nipple.Which of the following is the best next step in her evaluation?
Answer(s): D
Both the bloody nipple discharge and the microcalcifications are indications for a breast biopsy. Although there are benign-appearing radiographic calcifications, clusters of calcification are associated with a 25% chance of a cancer. An image-guided percutaneous biopsy is preferred because a fine- needle biopsy has about a 20% false negative rate. Cytology is a screening tool. In the presence of significant risk factors for cancer, a tissue diagnosis is mandatory. Imaging studies are also screening tools with a false negative and a false positive rate, making such studies inappropriate fordiagnosis
A 55-year-old woman has a bloody discharge from her left breast. A mammogram discloses a cluster of microcalcifications 3 cm beneath her left nipple.Which of the following is the principal advantage of a fine-needle aspiration of a breast mass?
The advantages of a fine-needle aspiration of a breast mass are that it can distinguish between a cystic and solid lesion, and it reduces the number of open breast biopsies when it is positive for cancer. However, a negative needle biopsy is nondiagnostic (and nonreassuring), and an open biopsy is still necessary. A fineneedle biopsy does not differentiate between noninvasive and invasive cancer, nor does it delineate the extent of in situ disease. Most breast surgeons will not perform definitive surgery (e.g., mastectomy or lumpectomy with lymph node dissection) without histologic confirmation of cancer: core-needle biopsy, surgical biopsy, or frozen section at the time of lumpectomy or mastectomy
A 55-year-old woman has a bloody discharge from her left breast. A mammogram discloses a cluster of microcalcifications 3 cm beneath her left nipple.Which of the following factors is associated with the greatest lifetime risk for developing breast cancer?
The factor associated with the greatest lifetime risk for developing breast cancer is age of the woman.Hereditary breast cancers account for 510% of all breast cancers and give the woman a relative risk of approximately 2. The relative risk is 4 with two first-degree relatives. Increased lifetime estrogen exposure is a minor risk factor for breast cancer. Obesity, early menarche, late menopause, and low parity are associated with an increased lifetime estrogen exposure and are minor risk factors for breast cancer. The prevalence of breast cancer increased from 30 per 10,000 women years (no hormone replacement) to 38 per 10,000 women years (women on hormone replacement), according to data from the Women's Health Initiative. This increase was not statistically significant, but the hormone arms of the study were stopped after 5.56 years because a prestudy threshold defined by the investigators' Data Safety Monitoring Board was exceeded. Stated otherwise, the risk of breast cancer increases from 3.3 to 4.1 per 1000 women using hormone replacement. Estrogens are considered promoters of breast cancer rather than inducers or initiators.
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