The most common cause of immediate postpartum haemorrhage is uterine atony, not trauma to the genital tract.

Correct Answer: A

Rationale: The correct answer is A: TRUE. Uterine atony is the most common cause of immediate postpartum hemorrhage due to inadequate uterine contraction to control bleeding. This is supported by research and clinical evidence. Trauma to the genital tract is a less common cause and usually leads to delayed hemorrhage. Choice B is incorrect as uterine atony is a well-documented primary cause. Choice C is incorrect as uterine atony is consistently the leading cause. Choice D is incorrect as the cause of immediate postpartum hemorrhage is clear, with uterine atony being the most common culprit.

Correct Answer: C

Rationale: The correct answer is C because in obstructive shock due to a large pulmonary embolus, there is increased resistance to blood flow out of the right ventricle, leading to elevated right ventricular pressure. This causes a backup of blood into the pulmonary circulation, increasing left ventricular pressure. The increased left ventricular pressure results in decreased cardiac output as the left ventricle struggles to pump against the increased resistance. A: Elevated atrial and decreased ventricular pressures - This is incorrect as obstructive shock typically results in elevated ventricular pressures due to increased resistance. B: Elevated right-sided and decreased left-sided pressures - This is partially true, but C is a more complete answer that explains the consequences of these pressures on cardiac output. D: Elevated left ventricular pressure and decreased systemic vascular resistance - This is incorrect as obstructive shock leads to increased, not decreased, systemic vascular resistance due to the embolus obstructing blood flow.

Correct Answer: B

Rationale: The correct answer is B: Lipoma. A lipoma is a common benign tumor made of fat cells. In this case, the patient's presentation of a painless, soft, round, flesh-colored lump with smooth borders is consistent with a lipoma. The absence of symptoms like pain, erythema, or tenderness further supports this diagnosis. Lipomas are usually non-tender to palpation and can grow to a significant size. The other choices (A, C, D) are not the correct answers because they do not align with the characteristics described in the patient's presentation. Neurolemma is associated with nerve sheath tumors, hemangioma with blood vessel tumors, and lymphangioma with lymphatic vessel tumors, none of which match the clinical findings in this case.

Correct Answer: B

Rationale: The correct answer is B: Inadequate surfactant levels. Surfactant is a substance that reduces surface tension in the alveoli, preventing their collapse. In respiratory distress syndrome, premature infants have insufficient surfactant production, leading to collapsed alveoli and difficulty breathing. Choice A is incorrect because it focuses on quality rather than quantity of surfactant. Choice C is incorrect as rib cage underdevelopment is associated with congenital conditions like thoracic dystrophy, not RDS. Choice D is incorrect as gradual alveolar rupture is not a known cause of RDS.

Correct Answer: B

Rationale: The correct answer is B: CT urogram. This is the appropriate next step in the workup for Melanie's microscopic hematuria. A CT urogram can provide detailed imaging of the urinary tract to identify any structural abnormalities or causes of hematuria. A urology consultation (choice A) may be necessary after the imaging results. Upper urinary imaging (choice C) is not specific enough and may not provide a comprehensive evaluation. Cystoscopy (choice D) is invasive and typically reserved for cases where lower urinary tract issues are suspected, which is not indicated in Melanie's case without further evaluation.

Correct Answer: D

Rationale: Rationale: 1. Obstructed labor can lead to prolonged pressure on the uterus, causing hemorrhage and uterine rupture (A). 2. Prolonged labor can result in fetal distress due to reduced oxygen supply and potential infection (B). 3. Therefore, both complications mentioned in A and B can occur in obstructed labor. Summary: A: Incorrect - Preterm birth and asphyxia are not directly related to obstructed labor. B: Incorrect - Only fetal distress and infection are commonly associated with obstructed labor. C: Incorrect - Both A and B are possible complications of obstructed labor, making D the correct choice.

Correct Answer: A

Rationale: The correct answer is A: There is a slightly higher risk of neurologic complications. Rationale: 1. Off-pump bypass grafting involves performing surgery on a beating heart without the use of a heart-lung machine. 2. The lack of cardiopulmonary bypass during off-pump surgery can lead to reduced blood flow to the brain, increasing the risk of neurologic complications. 3. This is why the AGACNP advises Mr. Nelson about the slightly higher risk of neurologic complications associated with off-pump bypass. 4. Choice B is incorrect as long-term results actually suggest similar or better patency rates for grafts in off-pump surgery. 5. Choice C is incorrect as the statement about the incidence increasing significantly in the last 10 years is not relevant to the risks of off-pump surgery. 6. Choice D is incorrect as off-pump surgery is not considerably more expensive and the correlation with better long-term outcomes is debatable.

Correct Answer: D

Rationale: The correct answer is D: Compound presentation. This term refers to the situation where there is more than one part of the fetus on the pelvic brim at the onset of labor. This can include a hand or arm alongside the head or another body part. The other choices are incorrect because: A: Unstable lie refers to the fetus being in a transverse position. B: Fetal malpresentation indicates an abnormal presentation of the fetus, such as breech or transverse. C: Fetal malposition refers to the fetus being in a suboptimal position, like occiput posterior. Thus, the best choice is D as it specifically describes the scenario of multiple fetal parts on the pelvic brim.

Correct Answer: D

Rationale: The correct answer is D. A ruptured uterus can lead to fetal distress and necessitate a cesarean section. Failure of the cervix to dilate is indicative of a potential uterine rupture, as the uterus may not be able to contract effectively due to the rupture. Maternal dehydration (A), pyrexia (B), and oliguria (C) are not specific signs of a ruptured uterus and may be present in various other conditions. Therefore, failure of the cervix to dilate is the most relevant early sign in this scenario.