HESI Pharmacology Practice Exam

Correct Answer B: Triglyceride level

Explanation:

Isotretinoin (commonly prescribed for severe acne) can have significant systemic side effects, including alterations in lipid metabolism. One of the key concerns is the potential for an increase in triglyceride levels, which can sometimes lead to pancreatitis if they become excessively elevated. Therefore, triglyceride level testing is required before starting isotretinoin and periodically throughout treatment to monitor for this potential adverse effect. Elevated triglycerides are a known side effect of isotretinoin and may require dose adjustments or discontinuation of the drug if levels become too high.

Explanation of Incorrect Options:

A. Platelet count:

While isotretinoin can affect various blood cell counts, it is not typically associated with significant changes in platelet count. Therefore, platelet count is not the primary lab test ordered before starting isotretinoin.

C. Complete blood count (CBC):

A CBC may be performed as part of general health monitoring, but triglyceride levels are more directly relevant to isotretinoin therapy, as the medication can lead to lipid disturbances.

D. White blood cell count:

Isotretinoin is not typically associated with significant effects on the white blood cell count. Although leukopenia may be a rare side effect, it is not the primary concern compared to triglyceride monitoring.

Summary:

Triglyceride level (B) is the correct laboratory test to monitor for potential lipid abnormalities and pancreatitis in clients prescribed isotretinoin for severe acne. While other blood tests like a complete blood count (C) or platelet count (A) might be monitored as part of routine care, triglyceride levels are specifically critical for assessing the safety of isotretinoin therapy.

Correct Answer D: Withhold the medication and call the HCP if the pulse is less than 60 beats per minute.

Explanation of Correct Answer:

Digoxin (Lanoxin) is a cardiac glycoside used to treat heart failure and certain arrhythmias by increasing the force of contraction and slowing the heart rate. One of the most important nursing considerations when administering digoxin is to monitor the heart rate. Bradycardia (a heart rate of less than 60 beats per minute) is a known adverse effect of digoxin and may indicate digoxin toxicity or that the medication is affecting the heart too strongly. If the pulse is less than 60 beats per minute, the nurse should withhold the medication and contact the healthcare provider to ensure the safety of the client.

Why the Other Options Are Incorrect:

A. Count the radial and carotid pulses every morning.

While it is important to monitor pulse rates before administering digoxin, checking both the radial and carotid pulses every morning is not necessary. The nurse should focus on counting the radial pulse as it is more accessible. It is also essential to note that carotid pulses should be avoided in some situations, such as in patients with cervical spine issues or those prone to carotid sinus hypersensitivity, where pressure on the carotid artery could trigger bradycardia or syncope.

B. Check the blood pressure every morning and evening.

While it is important to monitor blood pressure, it is not a specific requirement when taking digoxin. Digoxin primarily affects the heart rate and contractility rather than blood pressure. However, in cases where the client also has hypertension or hypotension, it is reasonable to monitor blood pressure, but it is not the most critical action related to digoxin therapy.

C. Stop taking the medication if the pulse is higher than 100 beats per minute.

A pulse greater than 100 beats per minute does not necessarily require stopping digoxin. In fact, tachycardia is more commonly treated with digoxin, as it helps to slow the heart rate in cases of atrial fibrillation or other arrhythmias. Therefore, if the pulse is above 100 beats per minute, the medication should not be stopped, and the nurse should consult with the healthcare provider regarding any changes in treatment.

Summary:

The nurse should withhold digoxin and contact the healthcare provider if the pulse is less than 60 beats per minute, as this may indicate digoxin toxicity or excessive heart rate suppression. Monitoring pulse rate is a critical aspect of care, but checking blood pressure or stopping the medication for a pulse over 100 beats per minute is not the appropriate action.

Correct answer B: 10

Detailed explanation of the correct answer:

To calculate the rate of oxytocin being infused in milliunits per minute, let's break down the problem step by step.

Step 1: Convert the total amount of oxytocin available in the solution to milliunits.

The available solution contains 20 units of oxytocin in 1,000 mL of Ringer's Lactated solution.

1 unit = 1,000 milliunits.

Thus, 20 units = 20 × 1,000 = 20,000 milliunits.

Step 2: Determine how many milliunits are in 1 mL of solution.

The total volume of the solution is 1,000 mL.

Therefore, each mL contains 20,000 milliunits ÷ 1,000 mL = 20 milliunits/mL.

Step 3: Calculate how many milliunits are being delivered per minute.

The infusion pump is programmed to deliver 30 mL/hour.

To convert this to mL/minute, divide by 60 minutes:

30 mL/hour ÷ 60 minutes/hour = 0.5 mL/minute.

Step 4: Calculate the rate in milliunits/minute.

Each mL contains 20 milliunits of oxytocin.

Therefore, at 0.5 mL/minute, the infusion delivers:

0.5 mL/minute × 20 milliunits/mL = 10 milliunits/minute.

Explanation of why the other options are incorrect:

A. 5 milliunits/minute is incorrect because it underestimates the amount being delivered.

C. 15 milliunits/minute is incorrect because it overestimates the delivery rate.

D. 20 milliunits/minute is incorrect because it would only be correct if the infusion rate were higher than 30 mL/hour.

Summary:

The client is receiving 10 milliunits per minute of oxytocin.

Correct Answer D: Human immunodeficiency virus (HIV) infection

Explanation of Correct Answer:

Lamivudine (Epivir) is an antiretroviral medication that is commonly used in the treatment of human immunodeficiency virus (HIV) infection. It works by inhibiting the reverse transcriptase enzyme, which is essential for the replication of the HIV virus. Lamivudine is often used in combination with other antiretroviral drugs as part of highly active antiretroviral therapy (HAART) to manage HIV infection and prevent progression to AIDS.

Why the Other Options Are Incorrect:

A. Pancreatitis

Lamivudine is not prescribed to treat pancreatitis. While pancreatitis may be a potential adverse effect of some medications, lamivudine itself is not a treatment for this condition. The management of pancreatitis typically involves supportive care and addressing the underlying cause.

B. Pharyngitis

Lamivudine is not prescribed for pharyngitis (sore throat), which is typically caused by viral or bacterial infections. Treatment for pharyngitis depends on the underlying cause (e.g., antibiotics for bacterial infections like streptococcal pharyngitis, supportive care for viral causes). Lamivudine is not effective for this condition.

C. Tonic-clonic seizures

Lamivudine is not used to treat tonic-clonic seizures. Seizures are typically managed with anticonvulsant medications, and lamivudine is not part of this therapeutic regimen. The treatment of seizures involves drugs like phenytoin, valproate, or levetiracetam, depending on the specific cause.

Summary:

Lamivudine (Epivir) is used to treat HIV infection by inhibiting the replication of the virus. It is not used to treat pancreatitis, pharyngitis, or tonic-clonic seizures.

Correct Answer A: Heart rate

Explanation of the Correct Answer: When administering digoxin (Lanoxin), it is essential to assess the heart rate before administration, as this medication is primarily used to increase the force of heart contractions and slow the heart rate in cases of heart failure and atrial fibrillation. A low heart rate, typically below 60 beats per minute, could indicate that the client is at risk for digoxin toxicity, as the medication can further slow the heart rate. If the heart rate is below 60 beats per minute, the nurse should withhold the dose and notify the healthcare provider.

Why the Other Options Are Incorrect:

B. Temperature Although temperature is an important indicator of infection or other systemic issues, it is not the most critical vital sign to assess when administering digoxin. A change in temperature would not immediately affect the decision to administer digoxin.

C. Respirations Respiratory rate is important for monitoring respiratory status, but it is not the most relevant vital sign to assess before giving digoxin. Respiratory issues may arise if the heart failure is severe, but heart rate is more directly influenced by digoxin.

D. Blood pressure While blood pressure is important to monitor in clients with heart failure and in those receiving digoxin, it is not as directly relevant as heart rate for determining whether the medication should be administered. Blood pressure may be affected by the client’s heart condition, but heart rate plays a more direct role in digoxin’s effects and safety.

Summary:

The most important vital sign to assess before administering digoxin is the heart rate because it directly relates to the medication's effects on the heart. If the heart rate is too low, the medication should be withheld to prevent the risk of bradycardia and potential digoxin toxicity.

Correct Answer D: Compete with estradiol for binding to estrogen in tissues containing high concentrations of receptors

Explanation:

Tamoxifen is a selective estrogen receptor modulator (SERM) used primarily in the treatment of hormone receptor-positive metastatic breast cancer. Its primary mechanism of action is to compete with estradiol (a natural estrogen) for binding to estrogen receptors on tumor cells. By binding to these receptors, tamoxifen blocks the action of estrogen, preventing it from stimulating the growth of estrogen-dependent breast cancer cells. This makes tamoxifen an effective treatment in estrogen receptor-positive breast cancer.

Explanation of Incorrect Options:

A. Increase DNA and RNA synthesis – This is not the mechanism of action of tamoxifen. While certain chemotherapy agents may work by affecting DNA and RNA synthesis, tamoxifen's role is more specific to blocking estrogen's effects on the tumor.

B. Promote the biosynthesis of nucleic acids – Tamoxifen does not promote nucleic acid biosynthesis. Its action is centered on blocking estrogen from binding to receptors on cancer cells.

C. Increase estrogen concentration and estrogen response – Tamoxifen does not increase estrogen levels. Instead, it inhibits estrogen's effects on tumor cells, particularly in hormone receptor-positive breast cancers.

Summary:

Tamoxifen primarily works by competing with estradiol for binding to estrogen receptors on breast cancer cells, preventing estrogen from stimulating cancer growth. Correct answer: D. Compete with estradiol for binding to estrogen in tissues containing high concentrations of receptors.

Correct Answer B: 2.3 ml

Explanation:

We are given:

Prescribed dose of amikacin = 0.572 grams

Available concentration = 250 mg/ml

Step 1: Convert the prescribed dose to milligrams.

0.572 grams × 1000 = 572 mg

Step 2: Use the concentration to calculate the volume to administer.

572 mg ÷ 250 mg/ml = 2.288 ml

Step 3: Round to the nearest tenth.

2.288 rounds to 2.3 ml

Explanation of Incorrect Options:

A. 2.0 ml – This would provide only 500 mg, which is less than the prescribed 572 mg.

C. 2.5 ml – This would provide 625 mg, which is more than prescribed.

D. 2.7 ml – This would provide 675 mg, which is much higher than the prescribed dose.

Summary:

The nurse should add 2.3 ml of amikacin to the infusion to deliver the correct dose. Correct answer: B. 2.3 ml.

Correct Answer D: Cough and chest pain

Why this answer is correct:

Cough and chest pain may indicate the development of pulmonary toxicity, a rare but serious adverse effect associated with nitrofurantoin (Macrodantin). This medication can cause acute, subacute, or chronic pulmonary reactions, including interstitial pneumonitis or pulmonary fibrosis, especially with long-term use. These symptoms require immediate discontinuation of the drug and prompt medical evaluation, as continued use can lead to severe, irreversible lung damage.

Why the other options are incorrect:

A. Nausea

Nausea is a common and usually mild gastrointestinal side effect of nitrofurantoin. It can often be managed by taking the medication with food or adjusting the dose. It does not require discontinuation of the drug unless it becomes severe or persistent.

B. Diarrhea

Like nausea, diarrhea can occur as a common gastrointestinal side effect. While it may require symptomatic management or monitoring for superinfection (e.g., Clostridium difficile), it is not a reason to immediately discontinue the medication unless it becomes severe.

C. Anorexia

Anorexia may occur as a general side effect of many antibiotics, including nitrofurantoin. It is typically not life-threatening and does not necessitate stopping the medication unless it leads to significant weight loss or nutritional deficits.

Summary:

Nitrofurantoin can cause pulmonary toxicity, particularly with prolonged use. Cough and chest pain are early signs of this serious complication and must be reported immediately, prompting the discontinuation of the medication. Therefore, D is the correct answer.

Correct Answer C: Consult with health care providers (HCPs) before receiving immunizations

Explanation:

When a patient is receiving an antineoplastic (chemotherapy) medication, they are often immunocompromised due to the medication's effects on the immune system. Many chemotherapy agents can weaken the immune system, making the patient more vulnerable to infections. As a result, it is crucial for the nurse to instruct the patient to consult with their healthcare provider (HCP) before receiving any immunizations, as live vaccines or certain other vaccines may not be appropriate during chemotherapy. The healthcare provider can guide the patient on which vaccines are safe to receive and when.

Explanation of Incorrect Options:

A. To take aspirin (acetylsalicylic acid) as needed for headache – This is not appropriate advice. Aspirin can increase the risk of bleeding, especially for patients undergoing chemotherapy, as chemotherapy can affect platelet counts and blood clotting. Non-steroidal anti-inflammatory drugs (NSAIDs) like aspirin should generally be avoided during chemotherapy unless specifically prescribed by the healthcare provider.

B. Drink beverages containing alcohol in moderate amounts each evening – Alcohol can interfere with the immune system, increase the risk of liver toxicity, and exacerbate side effects of chemotherapy, such as nausea and fatigue. Patients receiving chemotherapy should avoid alcohol unless specifically cleared by their healthcare provider.

D. That it is not necessary to consult HCPs before receiving a flu vaccine at the local health fair – This is incorrect. As mentioned in option C, patients receiving chemotherapy should consult their healthcare provider before receiving any vaccines, including the flu vaccine. Flu vaccines are typically inactivated (not live), but it is still crucial to consult with the healthcare provider to ensure the vaccine is appropriate for the patient’s current condition and immune status.

Summary:

Patients receiving antineoplastic medications should consult with their healthcare provider before receiving any immunizations due to their compromised immune system. Correct answer: C. Consult with health care providers (HCPs) before receiving immunizations.