MSN 611 : Clinical Pharm & Intervention for APRNs - NKU

Correct Answer:

C - a bloated and tense tympanic abdomen.

Explanation of the Correct Answer:

Pyloric stenosis in a 6-week-old infant is characterized by nonbilious, projectile vomiting, which typically occurs shortly after feeding (postprandial). The infant often appears hungry after vomiting and may be at risk for dehydration due to the loss of fluids. One of the classic physical findings in pyloric stenosis is the presence of an olive-shaped mass in the right upper quadrant of the abdomen, which is a hypertrophied pylorus. Sunken orbits and a depressed anterior fontanelle indicate dehydration, which is a common complication of pyloric stenosis due to vomiting.

However, a bloated and tense tympanic abdomen would be unexpected in pyloric stenosis. This type of abdominal distention suggests a different pathology, such as intestinal obstruction or another cause of gas accumulation in the intestines, not pyloric stenosis. In pyloric stenosis, the abdomen may be slightly distended but is not typically bloated or tense.

Why the Other Options Are Incorrect:

A - Postprandial projectile vomiting that is nonbilious:

This is one of the hallmark symptoms of pyloric stenosis. The hypertrophied pylorus causes an obstruction that leads to forceful vomiting after feeding, and the vomit is nonbilious because the obstruction is above the bile duct entry into the small intestine.

B - Sunken orbits and depressed anterior fontanelle, indicating dehydration:

Dehydration is a common complication of pyloric stenosis due to frequent vomiting. Infants with pyloric stenosis may develop signs of dehydration, such as sunken orbits (eyes) and a depressed fontanelle (the soft spot on the skull). These signs indicate fluid loss that needs to be addressed.

D - An olive-shaped mass in the right upper quadrant of the abdomen:

This is a classic finding in pyloric stenosis. The mass represents the hypertrophied pyloric muscle and can often be palpated in the right upper quadrant, just to the right of the midline. It is considered a key diagnostic sign for this condition.

Correct Answer:

C - Labetalol.

Explanation of the Correct Answer:

Labetalol is a non-selective beta-blocker with alpha-1 blocking properties that is commonly used in hypertensive emergencies. The combination of beta-blockade and alpha-1 blockade helps to reduce both heart rate and vascular resistance, which makes labetalol particularly effective in rapidly lowering blood pressure in emergency situations. It can be administered intravenously for quick action and is often used in acute settings such as hypertensive crises or emergencies.

Why the Other Options Are Incorrect:

A - Metoprolol tartrate:

Metoprolol tartrate is a cardioselective beta-blocker, primarily blocking beta-1 receptors, and is typically used for managing chronic hypertension and heart conditions, such as heart failure or arrhythmias. It is not commonly used for hypertensive emergencies because it lacks the alpha-1 blockade that would help in reducing peripheral vascular resistance. Intravenous formulations are available but may not be as effective in rapidly managing blood pressure in a hypertensive crisis.

B - Nadolol:

Nadolol is a non-selective beta-blocker that is used for chronic management of hypertension and angina. However, it is not typically used in hypertensive emergencies. Its long duration of action and lack of alpha-1 receptor blockade make it less suitable for the acute reduction of blood pressure in emergencies.

D - Bisoprolol:

Bisoprolol is a cardioselective beta-1 blocker, similar to metoprolol, and is used for chronic management of hypertension and heart failure. Like metoprolol, it is not typically used in hypertensive emergencies, as it does not offer the necessary rapid blood pressure reduction seen with labetalol in acute settings.

Correct Answer:

A - Hoarseness

Explanation of the Correct Answer:

Croup is a viral respiratory infection commonly seen in young children, typically caused by the parainfluenza virus. The hallmark symptoms include a barking cough, which often sounds like the child is barking like a seal. Another common symptom is hoarseness due to inflammation of the larynx (voice box). Hoarseness results from irritation and swelling of the vocal cords, making the voice sound raspy or weak.

Why the Other Options Are Incorrect:

B - Prolonged expiratory phase:

While croup primarily affects the upper airway, causing inflammation in the larynx and trachea, it generally does not result in a prolonged expiratory phase, which is more typical of lower respiratory issues, such as asthma or bronchiolitis. In croup, the main issue is inspiration, and the inspiratory stridor (a high-pitched sound during inhalation) is a characteristic feature.

C - Difficulty swallowing:

Difficulty swallowing is not a common symptom of croup. It may be seen in other conditions that affect the throat, such as tonsillitis or pharyngitis, but it is not a primary symptom of croup.

D - Lethargy:

Lethargy or extreme fatigue would be more concerning in cases of severe illness, such as sepsis or severe respiratory distress. In croup, the child is usually alert and exhibits symptoms like the barking cough and hoarseness. Lethargy would be a concerning sign if present and might suggest the need for urgent intervention, but it is not typically associated with mild to moderate croup.

Correct Answer:

D - GI disorders.

Explanation of the Correct Answer:

H2 antihistamines, such as ranitidine and famotidine, are primarily used in the treatment of gastrointestinal (GI) disorders, including peptic ulcers, gastroesophageal reflux disease (GERD), and Zollinger-Ellison syndrome. These medications work by blocking histamine receptors in the stomach lining, thereby reducing acid secretion and promoting healing of ulcers and esophageal irritation. Their use in GI disorders is well-supported due to their ability to decrease stomach acid production.

Why the Other Options Are Incorrect:

A - Allergies:

H2 antihistamines are not the first-line treatment for allergies. They are primarily used for GI issues. For allergies, H1 antihistamines, such as diphenhydramine or loratadine, are more commonly prescribed as they target histamine receptors involved in allergic responses.

B - Insomnia:

H2 antihistamines are not used to treat insomnia. First-generation H1 antihistamines like diphenhydramine are sometimes used as short-term sleep aids, but H2 antihistamines are not effective for inducing sleep.

C - Acne:

H2 antihistamines do not treat acne. Acne is generally managed with topical treatments, oral antibiotics, or other specific medications like retinoids. H2 antihistamines do not have any significant role in acne management.

Correct Answer:

A. Starting rifampin

Explanation of the Correct Answer:

Rifampin is a potent cytochrome P450 (CYP450) enzyme inducer, particularly CYP2C9, which is involved in the metabolism of warfarin. When a patient is on warfarin, starting rifampin can increase the metabolism of warfarin, decreasing its plasma concentration and reducing its anticoagulant effect. This interaction can lead to hypercoagulability, increasing the risk of clot formation, which in this case likely contributed to the formation of pulmonary emboli (PE).

In this patient, after starting rifampin, the anticoagulant effect of warfarin was likely diminished, allowing for the development of a thrombus that later embolized to the lungs. Even though the patient was initially started on heparin, the subsequent insufficient anticoagulation due to rifampin’s effect on warfarin might have led to the fatal pulmonary emboli.

Why the Other Options Are Incorrect:

B. The development of acid-fast bacterial infection

While tuberculosis (due to the acid-fast bacteria) can cause severe illness, including a hypercoagulable state due to chronic inflammation, it is not directly responsible for triggering the chain of events leading to pulmonary embolism. The infection would not have been the primary cause of her thrombotic event, as the pulmonary embolism was more likely triggered by the drug interaction between rifampin and warfarin.

C. The air travel itself

Air travel can increase the risk of deep vein thrombosis (DVT) due to prolonged immobility, which can lead to the formation of blood clots. However, this patient's primary risk factor for thromboembolism appears to be the interaction between rifampin and warfarin, not the travel itself. The pulmonary embolism was likely related to the suboptimal anticoagulation from warfarin after rifampin was started, rather than a DVT caused by the flight.

D. Use of heparin for three days

Heparin is an effective anticoagulant, and its short-term use would not have contributed to hypercoagulability. In fact, heparin would have provided initial anticoagulation. The issue arose after the switch to warfarin, where rifampin induced the metabolism of warfarin and diminished its efficacy, leading to the formation of thrombi. Therefore, heparin use was not the cause of the pulmonary embolism.

Correct Answer:

A. Inhibition of bacterial DNA gyrase (quinolones)

Explanation of the Correct Answer:

Ciprofloxacin is a fluoroquinolone antibiotic. Its mechanism of action involves the inhibition of bacterial DNA gyrase (also known as topoisomerase II) and topoisomerase IV. These enzymes are essential for DNA replication and repair in bacteria. DNA gyrase specifically is responsible for relieving the supercoiling tension that occurs ahead of the replication fork during DNA unwinding. By inhibiting these enzymes, ciprofloxacin prevents DNA replication, leading to bacterial cell death. This action is bactericidal, making ciprofloxacin effective against a broad range of gram-negative and some gram-positive organisms, including those causing urinary tract infections.

Why the Other Options Are Incorrect:

B. Inhibition of bacterial cell wall synthesis

This describes the mechanism of action of beta-lactam antibiotics (e.g., penicillins, cephalosporins). These antibiotics inhibit the synthesis of the bacterial cell wall by targeting penicillin-binding proteins (PBPs). Ciprofloxacin does not act on the cell wall; instead, it interferes with DNA replication by inhibiting DNA gyrase.

C. Inhibition of bacterial protein synthesis

This describes the mechanism of action of antibiotics like macrolides (e.g., azithromycin), tetracyclines (e.g., doxycycline), and aminoglycosides (e.g., gentamicin), which target the bacterial ribosome to prevent protein synthesis. Ciprofloxacin, however, targets bacterial DNA replication rather than protein synthesis.

D. Inhibition of bacterial folic acid synthesis

This describes the mechanism of action of sulfonamides and trimethoprim, which inhibit enzymes involved in the synthesis of folic acid, a critical vitamin for bacterial growth. Ciprofloxacin does not interfere with folic acid synthesis; it acts by inhibiting DNA gyrase.

Correct Answer:

B - Brainstem.

Explanation of the Correct Answer:

Triptans, which are a class of drugs used primarily to treat migraine headaches, exert their effects by acting as serotonin 1B and 1D agonists. These receptors are located primarily in the brainstem, which plays a crucial role in regulating the pain pathways involved in migraines. When triptans bind to these serotonin receptors, they help to constrict blood vessels, reduce inflammation, and inhibit the release of pain-inducing neuropeptides, thus alleviating the migraine symptoms. The brainstem is involved in modulating the transmission of pain signals from the brain to the rest of the body, making it the site of action for these drugs.

Why the Other Options Are Incorrect:

A - Temporal lobe:

The temporal lobe is involved in auditory processing, memory, and language, but it is not the primary site of action for triptans. While the temporal lobe may be affected in some neurological disorders, triptans specifically target receptors in the brainstem.

C - Occipital lobe:

The occipital lobe is primarily responsible for visual processing. While visual disturbances, such as auras, can occur with migraines, triptans do not act in the occipital lobe; instead, their effects are mediated in the brainstem, where pain processing occurs.

D - Thalamus:

The thalamus is involved in relaying sensory information to the cortex and is part of the pain processing pathway. However, the specific action of triptans is not centered in the thalamus but rather in the brainstem, where serotonin 1B and 1D receptors are concentrated.

Correct Answer:

A - syphilis during pregnancy may result in increased fetal mortality.

Explanation of the Correct Answer:

Syphilis is a sexually transmitted infection caused by Treponema pallidum and is particularly concerning during pregnancy because it can be transmitted to the fetus, leading to congenital syphilis. If left untreated, syphilis during pregnancy can lead to miscarriage, stillbirth, or preterm birth, and can also result in severe birth defects or neonatal death. Therefore, screening for syphilis in pregnant patients is essential to reduce the risk of fetal mortality and morbidity associated with congenital syphilis.

Why the Other Options Are Incorrect:

B - Hormonal changes associated with pregnancy may trigger activation of latent syphilis:

This is not accurate. While syphilis can exist in a latent form, hormonal changes during pregnancy do not trigger the activation of latent syphilis. The infection is typically transmitted to the fetus during pregnancy if the mother has an active syphilis infection. Screening is done to identify active syphilis before it can be passed to the fetus.

C - A positive result will preclude the need for a cesarean section at delivery:

This is not correct. While syphilis is a serious infection, it does not automatically determine the need for a cesarean section. A caesarean section might be recommended if the mother has active herpes simplex virus infection, which can be transmitted during vaginal delivery. However, syphilis is usually treated with antibiotics (penicillin) during pregnancy, and treatment reduces the risk of vertical transmission of the infection to the infant, making a cesarean section unnecessary in most cases.

D - Untreated syphilis can cause neonatal respiratory distress:

While syphilis can cause serious complications for the newborn, including congenital syphilis, it does not typically cause neonatal respiratory distress. Respiratory distress is more commonly seen in conditions like respiratory infections or prematurity. The primary concern with syphilis is its potential to cause birth defects, neurological issues, or even fetal death if left untreated, not respiratory distress.

Correct Answer:

A - scalp, elbows, and knees

Explanation of the Correct Answer:

Plaque psoriasis is the most common form of psoriasis, and it is characterized by raised, red patches covered with silvery-white scales. These lesions are commonly found on the scalp, elbows, and knees, which are classic sites for plaque psoriasis. The distribution of these lesions tends to be symmetrical, and these areas are prone to trauma and friction, which can exacerbate the condition (a phenomenon known as the Koebner response).

Why the Other Options Are Incorrect:

B - Hands, feet, and buttocks:

While psoriasis can affect the hands and feet, it is not the most common location for plaque psoriasis. Palmoplantar psoriasis, which affects the palms of the hands and soles of the feet, is a separate subtype of psoriasis. The buttocks are also not a typical location for plaque psoriasis lesions, making this option less accurate.

C - Forearms, back, and knees:

While the knees are a common location for plaque psoriasis, the forearms and back are less typical for the disease’s presentation. The forearms can be affected, but the scalp is more characteristic, as well as the elbows. The back is more often involved in other types of psoriasis, such as inverse psoriasis, but is not as commonly affected by plaque psoriasis.

D - Trunk and lower extremities:

Plaque psoriasis can affect the trunk and lower extremities, but this is not as common as the scalp, elbows, and knees. While it is possible for lesions to occur in these areas, they are less typical than the classic sites of involvement seen in plaque psoriasis.