NCLEX Practice Exam for Pharmacology: Maternal & Newborn Medications

EXPLANATION

 

✔Correct answer:

Instructing the client to avoid voiding before administration. Instructing the client to avoid voiding before administering Dinoprostone should be questioned. It is important for the client to void prior to the administration of Dinoprostone to ensure that the bladder is empty. An empty bladder helps reduce the risk of discomfort and potential complications during the procedure, and it also allows the medication to be placed more accurately.

Think of ensuring the bladder is empty before administering Dinoprostone like clearing the pathway before laying down new pavement. An empty bladder ensures that the medication can be administered without obstruction or added pressure.

Dinoprostone (a prostaglandin E2) is used to ripen the cervix and induce labor. It works by stimulating contractions of the uterine smooth muscle and softening the cervix, facilitating labor. Proper administration and accurate placement are crucial for its effectiveness, and an empty bladder can help achieve this.

 

✘Incorrect answer options:

Positioning the client in a side-lying position for 30 to 60 minutes post-administration. This is a standard protocol after administering Dinoprostone. Positioning the client in a side-lying position helps retain the medication and ensures it remains in place for optimal absorption and effectiveness.

Monitoring the client's vital signs during the procedure. Monitoring vital signs is a critical intervention to ensure the client’s safety and detect any adverse reactions early. This is a standard practice for any procedure involving the administration of medications to induce labor.

Ensuring the client voids prior to administration. This is a correct and necessary intervention. Having the client void before administration helps ensure proper placement of the medication and reduces discomfort.

 

References

• Lehne, R. A., & Rosenthal, L. D. (2019). Pharmacology for Nursing Care (10th ed.). Elsevier.
• Kee, J. L., Hayes, E. R., & McCuistion, L. E. (2018). Pharmacology: A Patient-Centered Nursing Process Approach (9th ed.). Saunders.

EXPLANATION

 

✔Correct answer:

Ischemic heart disease. Methylergonovine (Methergine) is an ergot alkaloid used to prevent or treat postpartum hemorrhage by inducing uterine contractions and vasoconstriction. However, it can also cause significant vasoconstriction in other parts of the body, including the coronary arteries. For patients with ischemic heart disease, this vasoconstriction can exacerbate their condition, potentially leading to angina or even myocardial infarction. Therefore, the presence of ischemic heart disease in the patient's medical history is a contraindication to the use of methylergonovine, and Nurse Patel should contact the prescribing physician for an alternative treatment.

Think of methylergonovine like a very strong coffee that constricts blood vessels. For someone with a heart condition (like ischemic heart disease), this strong coffee could be dangerous because it could further reduce blood flow to the heart, similar to how caffeine might make someone with high blood pressure feel worse.

Methylergonovine acts directly on the smooth muscle of the uterus and vasculature. It increases the tone, rate, and amplitude of uterine contractions, which helps to reduce bleeding by compressing blood vessels at the placental site. However, methylergonovine also induces generalized vasoconstriction, which can increase blood pressure and reduce blood flow to critical areas such as the heart. The drug is rapidly absorbed following oral administration, with onset of action typically within 5-10 minutes and lasting for several hours.

 

✘Incorrect answer options:

Hypothyroidism. Hypothyroidism is not a contraindication for methylergonovine use. While thyroid function can affect many body systems, there is no direct contraindication for the use of methylergonovine in patients with hypothyroidism.

Diabetes Mellitus. Diabetes mellitus requires careful management, particularly during the postpartum period, but it is not a direct contraindication for methylergonovine. Patients with diabetes should be monitored for potential complications, but methylergonovine can still be used.

Acute gastroenteritis. Acute gastroenteritis is an infection of the gastrointestinal tract and is not a contraindication for methylergonovine. While it may cause significant discomfort and dehydration, it does not impact the safety profile of methylergonovine directly.

 

References

• Lehne, R. A., & Rosenthal, L. D. (2019). Pharmacology for Nursing Care (10th ed.). Elsevier.
• Kee, J. L., Hayes, E. R., & McCuistion, L. E. (2018). Pharmacology: A Patient-Centered Nursing Process Approach (9th ed.). Saunders.

EXPLANATION

 

✔Correct answer:

Place the client in the supine position. Placing the client in the supine position should be avoided when managing hypertonic contractions. The supine position can decrease uterine blood flow and increase pressure on the inferior vena cava, reducing cardiac output and potentially exacerbating fetal distress. Instead, the client should be positioned in a side-lying position to improve uteroplacental perfusion and fetal oxygenation.

Think of the uterus like a garden hose. If you lie directly on the hose (supine position), you kink it and reduce water flow. Lying on your side allows the hose to flow freely, just like the side-lying position allows better blood flow to the uterus and baby.

Oxytocin is a synthetic hormone that stimulates uterine contractions by binding to oxytocin receptors in the uterine muscle, increasing intracellular calcium levels. Hypertonic contractions, characterized by excessively frequent, prolonged, or strong contractions, can impair uteroplacental blood flow and lead to fetal hypoxia. Proper management includes stopping the oxytocin infusion to reduce contraction strength and frequency, positioning the patient to enhance blood flow, and providing supplemental oxygen to improve fetal oxygenation.

 

✘Incorrect answer options:

Stop the oxytocin infusion. This is a correct and necessary action. Stopping the oxytocin infusion is crucial to reduce the intensity and frequency of contractions and prevent further complications.

Decrease the flow rate of the intravenous additive solution. Reducing the flow rate of the intravenous additive solution can help mitigate the effects of hypertonic contractions. It is an appropriate intervention to decrease the stimulation of uterine contractions.

Administer oxygen at 8 to 10 liters per minute. Administering oxygen is a correct intervention. Providing supplemental oxygen helps ensure that both the mother and fetus receive adequate oxygenation during periods of compromised blood flow caused by hypertonic contractions.

 

References

• Lehne, R. A., & Rosenthal, L. D. (2019). Pharmacology for Nursing Care (10th ed.). Elsevier.
• Kee, J. L., Hayes, E. R., & McCuistion, L. E. (2018). Pharmacology: A Patient-Centered Nursing Process Approach (9th ed.). Saunders.

EXPLANATION

 

✔Correct answer:

"The vitamin K will protect the newborn from bleeding." Vitamin K is essential for the synthesis of clotting factors in the liver, which are necessary for blood coagulation. Newborns are at risk for vitamin K deficiency because they have low stores of this vitamin at birth, and their intestinal bacteria, which help synthesize vitamin K, are not yet fully developed. Administering a vitamin K injection to a newborn helps to prevent a serious condition called Vitamin K Deficiency Bleeding (VKDB), which can lead to severe bleeding and hemorrhage. By providing this injection, we ensure that the newborn has enough vitamin K to produce adequate clotting factors and reduce the risk of bleeding.

Think of vitamin K like a crucial ingredient in a recipe for making glue. Without this ingredient, the glue won't stick properly, just as without vitamin K, the blood cannot clot effectively, leading to a higher risk of bleeding.

Vitamin K is a fat-soluble vitamin that plays a key role in the synthesis of prothrombin and other clotting factors (factors II, VII, IX, and X) in the liver. The injection provides an immediate source of vitamin K, bypassing the immature gut flora that would otherwise produce the vitamin over time. The onset of action is rapid, ensuring that the newborn has sufficient levels to prevent bleeding. The vitamin is stored in the liver and used as needed for the production of clotting factors.

 

✘Incorrect answer options:

"The vitamin K will protect against jaundice and anemia." Jaundice and anemia are not prevented by vitamin K. Jaundice is caused by elevated levels of bilirubin in the blood, and anemia is typically related to a deficiency in red blood cells or hemoglobin. Vitamin K's primary role is in blood clotting, not in managing bilirubin levels or red blood cell production.

"The vitamin K will prevent hyperbilirubinemia." Hyperbilirubinemia, or high levels of bilirubin in the blood, is not prevented by vitamin K. This condition is usually managed through phototherapy or other methods that help break down bilirubin. Vitamin K does not play a role in bilirubin metabolism.

"The vitamin K provides active immunity." Active immunity involves the production of antibodies in response to an antigen, such as through vaccination. Vitamin K does not provide immunity; it is solely involved in the synthesis of clotting factors to prevent bleeding.

 

References

• Lehne, R. A., & Rosenthal, L. D. (2019). Pharmacology for Nursing Care (10th ed.). Elsevier.
• Kee, J. L., Hayes, E. R., & McCuistion, L. E. (2018). Pharmacology: A Patient-Centered Nursing Process Approach (9th ed.). Saunders.

EXPLANATION

 

✔Correct answer:

Administering intratracheally. Lung surfactant is administered intratracheally to treat respiratory distress syndrome (RDS) in newborns. This route ensures that the surfactant is delivered directly to the lungs, where it can quickly reduce surface tension in the alveoli, improve lung compliance, and enhance oxygenation. Administering the surfactant via the intratracheal route allows it to spread throughout the alveoli, promoting more effective gas exchange and reducing the work of breathing for the newborn.

Think of the intratracheal administration of surfactant like adding oil directly to the engine of a car to ensure it runs smoothly. By applying the surfactant directly to the lungs, it helps them function more effectively, just as oil helps the engine run better.

Lung surfactant is a substance that reduces the surface tension of the fluid lining the alveoli in the lungs. In newborns with RDS, the lack of sufficient surfactant leads to alveolar collapse, impaired gas exchange, and increased work of breathing. Intratracheal administration ensures that the surfactant is delivered directly to the site of action. Once administered, the surfactant spreads across the alveolar surfaces, reducing surface tension and allowing the alveoli to remain open during exhalation, thus improving respiratory function and oxygenation.

 

✘Incorrect answer options:

Administering intravenously. Intravenous administration is not appropriate for surfactant therapy because the surfactant needs to be directly applied to the alveoli in the lungs to be effective. Intravenous administration would not achieve the desired therapeutic effect.

Administering intramuscularly. Intramuscular administration is not suitable for surfactant therapy as it would not deliver the medication to the lungs where it is needed to reduce alveolar surface tension and improve lung function.

Administering intradermally. Intradermal administration is used for allergy testing or certain vaccines but is not appropriate for delivering lung surfactant. This route would not reach the lungs and would be ineffective in treating RDS.

 

References

• Lehne, R. A., & Rosenthal, L. D. (2019). Pharmacology for Nursing Care (10th ed.). Elsevier.
• Kee, J. L., Hayes, E. R., & McCuistion, L. E. (2018). Pharmacology: A Patient-Centered Nursing Process Approach (9th ed.). Saunders.

EXPLANATION

 

✔Correct answer:

Random blood sugar. Dexamethasone is a corticosteroid, and one of its significant side effects is hyperglycemia (elevated blood sugar levels). Corticosteroids can increase blood glucose levels by promoting gluconeogenesis and decreasing glucose uptake by cells. Pregnant patients are already at a higher risk for gestational diabetes, and the administration of dexamethasone can further exacerbate this risk. Therefore, Nurse Lopez should prioritize regular monitoring of the patient's blood sugar levels to manage and mitigate any potential complications arising from hyperglycemia.

Think of dexamethasone like adding sugar to a drink. If you keep adding sugar, the drink becomes too sweet. Similarly, dexamethasone can increase blood sugar levels in the body, so it’s important to keep checking and make sure it doesn’t get too high.

Dexamethasone is a potent synthetic glucocorticoid with anti-inflammatory and immunosuppressant properties. It works by binding to glucocorticoid receptors, influencing the expression of specific genes involved in inflammation and metabolism. This includes increasing the production of glucose in the liver and reducing its uptake by muscle and fat tissue, leading to elevated blood sugar levels. Regular monitoring of blood glucose can help in timely intervention and management of any corticosteroid-induced hyperglycemia.

 

✘Incorrect answer options:

Uric acid. While uric acid levels can be relevant in monitoring conditions like preeclampsia, they are not directly affected by dexamethasone. Therefore, it is not the primary concern in this context.

Serum calcium. Dexamethasone can affect calcium metabolism, potentially leading to decreased calcium levels over long-term use. However, monitoring blood sugar levels takes precedence in the acute setting due to the immediate risks associated with hyperglycemia.

Red blood cell count. While corticosteroids can affect red blood cell production and may lead to an increase in red blood cell count over time, this is not the primary concern with short-term dexamethasone therapy. Monitoring blood glucose is more critical in the short term.

 

References

• Lehne, R. A., & Rosenthal, L. D. (2019). Pharmacology for Nursing Care (10th ed.). Elsevier.
• Kee, J. L., Hayes, E. R., & McCuistion, L. E. (2018). Pharmacology: A Patient-Centered Nursing Process Approach (9th ed.). Saunders.

EXPLANATION

 

✔Correct answer:

Developing Rh incompatibility. Rho(D) immune globulin (RhoGAM) is administered to Rh-negative mothers who have given birth to an Rh-positive baby to prevent the development of Rh incompatibility in future pregnancies. When an Rh-negative mother is exposed to Rh-positive fetal blood cells, her immune system may produce antibodies against these cells. In subsequent pregnancies, these antibodies can cross the placenta and attack the red blood cells of an Rh-positive fetus, leading to hemolytic disease of the newborn (HDN). RhoGAM works by preventing the mother's immune system from recognizing and producing antibodies against Rh-positive cells, thus protecting future pregnancies.

Think of RhoGAM as a "peacekeeper" that prevents a conflict. Just as a peacekeeper intervenes to prevent fighting between two groups, RhoGAM prevents the mother’s immune system from attacking Rh-positive cells, thereby maintaining peace between the mother and future Rh-positive pregnancies.

Pharmacodynamics and Pharmacokinetics: RhoGAM contains antibodies to the Rh(D) antigen. When administered to an Rh-negative mother, these antibodies bind to any Rh-positive fetal red blood cells that may have entered the mother's bloodstream, marking them for removal before the mother's immune system can react and produce antibodies against them. This prevents sensitization to the Rh antigen. RhoGAM is typically given at 28 weeks of pregnancy and within 72 hours after delivery of an Rh-positive baby, as well as after any event that could cause fetal-maternal hemorrhage, such as amniocentesis or trauma.

 

✘Incorrect answer options:

Developing German Measles. German measles, or rubella, is a viral infection, and RhoGAM has no role in its prevention. Vaccination with the MMR vaccine (measles, mumps, and rubella) is used to protect against German measles.

Having Rh+ blood. RhoGAM does not affect the blood type of the baby. It is used to prevent the mother from becoming sensitized to Rh-positive blood, but it does not change the Rh status of the baby.

Developing Pernicious anemia. Pernicious anemia is a condition caused by vitamin B12 deficiency due to the lack of intrinsic factor, not related to Rh incompatibility. RhoGAM does not prevent or treat pernicious anemia.

 

References

• Lehne, R. A., & Rosenthal, L. D. (2019). Pharmacology for Nursing Care (10th ed.). Elsevier.
• Kee, J. L., Hayes, E. R., & McCuistion, L. E. (2018). Pharmacology: A Patient-Centered Nursing Process Approach (9th ed.). Saunders.

EXPLANATION

 

✔Correct answer:

"I will flush the newborn‘s eyes after instilling the ointment."  Flushing the newborn's eyes after administering erythromycin ointment is incorrect and indicates a need for further research. Erythromycin ophthalmic ointment is applied to prevent neonatal conjunctivitis, commonly caused by Neisseria gonorrhoeae or Chlamydia trachomatis. Flushing the eyes would remove the medication, rendering it ineffective in providing the necessary prophylactic treatment.

Imagine applying sunscreen to your skin for protection from sunburn and then immediately washing it off. The sunscreen would not have a chance to protect your skin, just like the erythromycin ointment would not have a chance to protect the newborn’s eyes if it is flushed out.

Erythromycin works by inhibiting bacterial protein synthesis, effectively preventing the bacteria from replicating. When applied as an ointment, it provides a protective barrier against potential bacterial infections. The ointment should remain in the conjunctival sac to ensure adequate contact time with the eye tissues, allowing the antibiotic to exert its prophylactic effect.

 

✘Incorrect answer options:

"I will clean the newborn‘s eyes before instilling the ointment." Cleaning the newborn’s eyes before instilling erythromycin ointment is a correct practice. It ensures that any debris or discharge is removed, which can help the medication to be more effective.

"I need to administer the eye ointment within an hour after maternal delivery." This statement is correct. Administering erythromycin within the first hour after birth is crucial for preventing infections that could be transmitted during delivery.

"I will instill the eye ointment into each of the newborn‘s conjunctival sacs." This is also correct. The ointment should be applied into the lower conjunctival sac of each eye to ensure proper distribution and efficacy of the medication.

 

References

• Lehne, R. A., & Rosenthal, L. D. (2019). Pharmacology for Nursing Care (10th ed.). Elsevier.
• Kee, J. L., Hayes, E. R., & McCuistion, L. E. (2018). Pharmacology: A Patient-Centered Nursing Process Approach (9th ed.). Saunders.

EXPLANATION

 

✔Correct answer:

Betamethasone (Celestone). Betamethasone is a corticosteroid administered to women at risk of preterm delivery to accelerate fetal lung maturation. Administering betamethasone helps increase the production of surfactant, which reduces the risk of neonatal respiratory distress syndrome (RDS). It is typically given between 24 and 34 weeks of gestation if preterm birth is imminent. If labor can be delayed for 48 hours, this provides enough time for the corticosteroid to enhance lung maturity significantly, thereby improving neonatal outcomes.

Think of betamethasone as a "crash course" for the baby's lungs. Just as a crash course quickly teaches someone the essentials, betamethasone quickly prepares the baby's lungs to function better outside the womb.

Betamethasone is a synthetic glucocorticoid that crosses the placenta and promotes the release of surfactant by stimulating type II pneumocytes in the fetal lungs. This enhances lung compliance and reduces the incidence of respiratory distress syndrome. The standard regimen involves two doses administered 24 hours apart. The drug's effects on lung maturation can significantly reduce neonatal morbidity and mortality associated with preterm birth.

 

✘Incorrect answer options:

Butorphanol tartrate (Stadol). Butorphanol is an opioid analgesic used for pain management during labor. While it can provide pain relief, it does not play a role in promoting fetal lung maturity or delaying preterm labor.

Fentanyl (Sublimaze). Fentanyl is another opioid analgesic used for pain relief in various medical settings, including during labor. It is effective for pain management but does not contribute to fetal lung development or preterm labor management.

Sufentanil (Sufenta). Sufentanil is an opioid analgesic used for pain relief during surgery and labor. Similar to fentanyl and butorphanol, it provides pain management but does not aid in fetal lung maturation or the management of preterm labor.

 

References

• Lehne, R. A., & Rosenthal, L. D. (2019). Pharmacology for Nursing Care (10th ed.). Elsevier.
• Kee, J. L., Hayes, E. R., & McCuistion, L. E. (2018). Pharmacology: A Patient-Centered Nursing Process Approach (9th ed.). Saunders.

EXPLANATION

 

✔Correct answer:

Grade 1. The grading of deep tendon reflexes ranges from 0 to 4, with Grade 0 indicating no response and Grade 4 indicating a very brisk, hyperactive response with clonus (repetitive muscle contractions). A Grade 1 reflex indicates a diminished but present response, which suggests hyporeflexia. This grading is particularly relevant for patients on magnesium sulfate therapy, as one of the signs of magnesium toxicity is diminished or absent deep tendon reflexes. Monitoring for Grade 1 reflexes is crucial, as it can be an early indicator of toxicity before more severe symptoms, such as respiratory depression, occur.

Think of the deep tendon reflexes like the volume on a radio. Grade 2 is normal volume, Grade 0 is the radio turned off, and Grade 1 is the volume turned down very low. For someone on magnesium sulfate, we need to make sure the radio isn’t turned down too low (Grade 1) or off completely (Grade 0), as this indicates magnesium toxicity.

Magnesium sulfate acts as a central nervous system depressant and a muscle relaxant by reducing acetylcholine release at neuromuscular junctions. Therapeutic levels help to prevent seizures in preeclampsia without significantly affecting respiratory or cardiac function. However, elevated magnesium levels can lead to toxic effects, including hyporeflexia (diminished reflexes), which are graded as Grade 1. Early detection of these signs allows for timely intervention to prevent progression to more severe toxicity.

 

✘Incorrect answer options:

Grade 0. Grade 0 indicates no reflex response at all, which is more severe than Grade 1. This suggests complete loss of the reflex, indicating significant magnesium toxicity.

Grade 2. Grade 2 is considered a normal reflex response. It suggests that the reflexes are within the normal range and not affected by the magnesium sulfate therapy.

Grade 4. Grade 4 indicates a very brisk, hyperactive response with clonus. This is the opposite of a diminished response and suggests hyperreflexia, which is not a typical concern with magnesium sulfate therapy.

 

References

• Lehne, R. A., & Rosenthal, L. D. (2019). Pharmacology for Nursing Care (10th ed.). Elsevier.
• Kee, J. L., Hayes, E. R., & McCuistion, L. E. (2018). Pharmacology: A Patient-Centered Nursing Process Approach (9th ed.). Saunders.

EXPLANATION

 

✔Correct answer:

Blood pressure. Before administering Methylergonovine (Methergine), it is crucial for Nurse Sarah to check the patient's blood pressure. Methylergonovine is a potent vasoconstrictor that can significantly increase blood pressure. Administering it to a patient with preexisting hypertension or elevated blood pressure could lead to dangerous complications, including hypertensive crisis or stroke. Therefore, assessing and ensuring that the patient’s blood pressure is within a safe range is the top priority before administration.

Think of Methylergonovine like a power tool that boosts pressure. Just as you wouldn’t want to use a power tool on a structure that’s already under high pressure to avoid causing damage, you wouldn’t want to give Methylergonovine to someone with high blood pressure without checking first.

Methylergonovine works by directly stimulating uterine and vascular smooth muscle, causing contraction of the uterus and vasoconstriction of blood vessels. This action is beneficial for managing postpartum hemorrhage by reducing uterine bleeding, but it also raises systemic vascular resistance and blood pressure. The medication is rapidly absorbed and has a quick onset of action, so ensuring that the patient's blood pressure is within a safe range before administration is essential to prevent adverse effects.

 

✘Incorrect answer options:

Vaginal bleeding. While assessing vaginal bleeding is important in the context of postpartum hemorrhage, it is not the immediate priority before administering Methylergonovine. The drug is given to control bleeding, but it must be ensured that it is safe to administer in terms of the patient’s blood pressure first.

Urine output. Monitoring urine output is essential for overall patient assessment, especially in terms of kidney function and fluid balance. However, it is not the most critical assessment prior to administering Methylergonovine, as blood pressure assessment takes precedence.

Deep tendon reflexes. Deep tendon reflexes are not directly relevant to the administration of Methylergonovine. They are more pertinent to monitoring magnesium sulfate therapy, where diminished reflexes can indicate toxicity.

 

References

• Lehne, R. A., & Rosenthal, L. D. (2019). Pharmacology for Nursing Care (10th ed.). Elsevier.
• Kee, J. L., Hayes, E. R., & McCuistion, L. E. (2018). Pharmacology: A Patient-Centered Nursing Process Approach (9th ed.). Saunders.

EXPLANATION

 

✔Correct answer:

B) Naloxone (Narcan). Naloxone is an opioid antagonist that is used to counteract the effects of opioid overdose, including severe respiratory depression. It works by binding to opioid receptors with a higher affinity than opioid agonists (like morphine or oxycodone), thereby displacing the opioid molecules and reversing their effects. This makes naloxone the ideal medication to have on hand for immediate use if Maria experiences opioid-induced respiratory depression during labor.

Think of naloxone as a "reset button" for the effects of opioids. Just as a reset button stops a device from malfunctioning and brings it back to its normal state, naloxone quickly reverses the dangerous effects of opioids and restores normal breathing.

Naloxone works by competitively binding to the same receptors in the brain that opioids bind to, specifically the mu, kappa, and delta opioid receptors. Because naloxone has a higher affinity for these receptors than most opioids, it can effectively displace the opioid molecules. The onset of action for naloxone is rapid, typically within 2 to 5 minutes when administered intravenously, and slightly longer when administered via intramuscular or subcutaneous routes. The half-life of naloxone is relatively short, about 30 to 81 minutes, which means that in some cases, multiple doses may be necessary to fully reverse opioid effects, especially with long-acting opioids.

 

✘Incorrect answer options:

Oxycodone (Oxycontin). Oxycodone is an opioid analgesic, not an opioid antagonist. Administering oxycodone would not help in cases of opioid-induced respiratory depression; in fact, it could worsen the situation by adding more opioid to the system, thereby increasing the risk of respiratory depression.

Morphine sulfate. Morphine is another opioid analgesic, similar to oxycodone. Like oxycodone, morphine would exacerbate opioid-induced respiratory depression rather than alleviate it. Therefore, it is not suitable for reversing the effects of an opioid overdose.

Meperidine hydrochloride (Demerol). Meperidine is also an opioid analgesic, and its use in this context would be inappropriate. Meperidine can cause respiratory depression similar to other opioids and would not counteract opioid-induced respiratory depression.

 

References

• Lehne, R. A., & Rosenthal, L. D. (2019). Pharmacology for Nursing Care (10th ed.). Elsevier.
• Kee, J. L., Hayes, E. R., & McCuistion, L. E. (2018). Pharmacology: A Patient-Centered Nursing Process Approach (9th ed.). Saunders.

EXPLANATION

 

✔Correct answer:

Respirations of 10 breaths per minute. One of the critical signs of magnesium sulfate toxicity is respiratory depression. Magnesium sulfate is a central nervous system depressant, and high levels can depress the respiratory center in the brain, leading to decreased respiratory rate. A respiratory rate of 10 breaths per minute is below the normal range (12-20 breaths per minute) and is indicative of potential toxicity. Immediate action is required to address this, including stopping the magnesium sulfate infusion and administering calcium gluconate as an antidote.

Think of magnesium sulfate like a dimmer switch for the nervous system. While it helps to reduce excessive activity (like in preeclampsia), too much can dim the lights too far, leading to problems like slowed breathing. In this analogy, a respiratory rate of 10 is like the lights being dimmed so much that it’s barely lit – a clear sign to turn the dimmer back up (or stop the medication).

Pharmacodynamics and Pharmacokinetics: Magnesium sulfate acts as a vasodilator and muscle relaxant by blocking neuromuscular transmission and decreasing the release of acetylcholine at the neuromuscular junction. This helps in managing preeclampsia by lowering blood pressure and preventing seizures. Therapeutic serum magnesium levels are typically maintained between 4-7 mEq/L for preeclampsia management. Levels above this range increase the risk of toxicity, with respiratory depression being a primary concern. The kidneys excrete magnesium, so adequate urine output is essential to prevent accumulation and toxicity.

 

✘Incorrect answer options:

Serum magnesium level of 7 mEq/L. While a serum magnesium level of 7 mEq/L is at the upper limit of the therapeutic range, it is not yet indicative of toxicity. However, levels above this range would be concerning.

Urine output of 25 mL/hr. This urine output is below the normal range (typically >30 mL/hr) and could indicate decreased renal function, which is a concern for magnesium excretion and potential toxicity. However, it is not as immediate a sign of toxicity as respiratory depression.

Presence of deep tendon reflexes. The presence of deep tendon reflexes (DTRs) generally indicates that magnesium levels are within the therapeutic range. Loss of DTRs would be a sign of magnesium sulfate toxicity, but their presence is not concerning.

 

References

• Lehne, R. A., & Rosenthal, L. D. (2019). Pharmacology for Nursing Care (10th ed.). Elsevier.
• Kee, J. L., Hayes, E. R., & McCuistion, L. E. (2018). Pharmacology: A Patient-Centered Nursing Process Approach (9th ed.). Saunders.

EXPLANATION

 

✔Correct answer:

Excessive uterine contractions. Excessive uterine contractions, also known as uterine tachysystole, can be a sign that the oxytocin (Pitocin) infusion needs to be terminated. Uterine tachysystole is defined as more than five contractions in a 10-minute period, averaged over 30 minutes. This condition can lead to reduced uteroplacental blood flow, resulting in fetal hypoxia and distress. It can also increase the risk of uterine rupture. Nurse Smith should immediately stop the oxytocin infusion if she observes excessive uterine contractions to prevent complications for both the mother and the baby.

Think of oxytocin as the gas pedal of a car. Excessive uterine contractions are like driving too fast, which can be dangerous. Just as you would ease off the gas pedal to slow down and avoid an accident, stopping the oxytocin infusion helps to slow down the contractions to keep both the mother and baby safe.

Oxytocin is a hormone that stimulates uterine contractions by increasing the intracellular calcium levels in uterine muscle cells. When administered to induce labor, it is given intravenously and its effects are quickly observed. The half-life of oxytocin is short, about 3-5 minutes, which allows for rapid adjustment of its effects. However, because its action can lead to strong and frequent contractions, careful monitoring is essential to prevent hyperstimulation of the uterus.

 

✘Incorrect answer options:

Fatigue. Fatigue is a common symptom during labor but is not a reason to terminate the oxytocin infusion. Management of fatigue includes providing rest periods and supportive care, but it does not indicate that the oxytocin infusion needs to be stopped.

Early decelerations of the fetal heart rate. Early decelerations are typically benign and often related to head compression during contractions. They are not usually a sign of fetal distress and do not necessitate stopping the oxytocin infusion. Continuous monitoring is necessary, but early decelerations alone are not a cause for discontinuation.

Nausea. Nausea can occur during labor for various reasons but is not directly related to the safety of oxytocin administration. It does not indicate the need to stop the oxytocin infusion. Management of nausea involves supportive care and possibly antiemetic medications.

 

References

• Lehne, R. A., & Rosenthal, L. D. (2019). Pharmacology for Nursing Care (10th ed.). Elsevier.
• Kee, J. L., Hayes, E. R., & McCuistion, L. E. (2018). Pharmacology: A Patient-Centered Nursing Process Approach (9th ed.). Saunders.