Which patient’s condition would raise concerns regarding the administration of labetalol (Normodyne)?
A patient diagnosed with COPD.
A patient suffering from narrow-angle glaucoma.
A patient with hypertension.
A patient exhibiting tachycardia.
The Correct Answer is B
Choice A rationale:
COPD (Chronic Obstructive Pulmonary Disease) is a chronic lung disease that causes airflow obstruction. While labetalol can cause some bronchoconstriction, it is generally considered safe for use in patients with COPD. However, it's essential to monitor respiratory status closely, especially in those with severe COPD.
Choice B rationale:
Narrow-angle glaucoma is an eye condition characterized by increased intraocular pressure (IOP) due to impaired drainage of aqueous humor. Labetalol can exacerbate this condition by further increasing IOP through its beta-blocking effects. This can lead to acute angle-closure glaucoma, a medical emergency that can result in permanent vision loss.
Specific mechanisms by which labetalol can increase IOP:
Reduced aqueous humor production: Beta-blockers like labetalol can decrease the production of aqueous humor, the fluid that maintains eye pressure. While this might seem beneficial, a significant reduction can lead to anterior chamber shallowing, which can mechanically block the drainage angle and trigger angle closure.
Impaired uveoscleral outflow: Beta-blockers can also impair the uveoscleral outflow pathway, an alternative route for aqueous humor drainage that becomes more important in glaucoma patients. This can further contribute to IOP elevation.
Vasoconstriction of ciliary blood vessels: Labetalol's alpha-blocking effects can cause vasoconstriction of the ciliary blood vessels, which supply blood to the ciliary body responsible for aqueous humor production. This can reduce blood flow and indirectly hinder aqueous humor drainage.
Pupillary dilation: Beta-blockers can cause pupillary dilation, which can mechanically narrow the anterior chamber angle and obstruct aqueous humor outflow.
Therefore, labetalol is generally contraindicated in patients with known narrow-angle glaucoma.
Choice C rationale:
Hypertension (high blood pressure) is one of the primary indications for labetalol. It is an effective antihypertensive medication that works by blocking beta receptors, leading to decreased heart rate, contractility, and blood pressure.
Choice D rationale:
Tachycardia (fast heart rate) can also be treated with labetalol due to its beta-blocking effects. It helps to slow down the heart rate and restore a normal rhythm.
Nursing Test Bank
Naxlex Comprehensive Predictor Exams
Related Questions
Correct Answer is C
Explanation
Choice A rationale:
Insulin resistance is a condition in which the body's cells become less responsive to insulin, requiring more insulin to maintain normal blood glucose levels.
It's primarily caused by factors such as obesity, physical inactivity, and genetic predisposition. Rotating injection sites does not directly address these underlying causes of insulin resistance.
It can help ensure consistent insulin absorption, but it's not the primary mechanism for preventing insulin resistance.
Choice B rationale:
Allergic reactions to insulin are rare but can occur.
They typically manifest as localized symptoms at the injection site, such as redness, swelling, itching, or pain.
In severe cases, systemic reactions like hives, difficulty breathing, or anaphylaxis can occur.
Rotating injection sites might reduce the risk of localized allergic reactions by preventing repeated exposure to insulin in the same area of skin.
However, it does not prevent systemic allergic reactions, which are immune-mediated and not dependent on the injection site.
Choice C rationale:
Lipodystrophy is a condition characterized by abnormal changes in fat distribution under the skin. It can occur as a complication of repeated insulin injections at the same site.
There are two main types of lipodystrophy:
Lipohypertrophy: This involves the accumulation of excess fatty tissue at injection sites, creating visible lumps or bumps. Lipoatrophy: This involves the loss of fatty tissue at injection sites, leading to depressions or indentations in the skin.
Both lipohypertrophy and lipoatrophy can interfere with insulin absorption, leading to unpredictable blood glucose control.
Rotating injection sites helps to prevent lipodystrophy by distributing insulin injections over a wider area of skin, reducing the likelihood of repeated trauma to the same tissue.
Choice D rationale:
Insulin shock, also known as hypoglycemia, is a condition that occurs when blood glucose levels drop too low.
It can be caused by several factors, including excessive insulin dosing, missed meals, or increased physical activity. Rotating injection sites does not directly affect the risk of insulin shock.
It's essential for individuals using insulin to monitor their blood glucose levels regularly, adjust insulin doses as needed, and follow a balanced diet and exercise plan to prevent hypoglycemia.
Correct Answer is C
Explanation
Choice A rationale:
Erythromycin ointment does not have moisturizing properties. Its primary purpose is to prevent bacterial infection, not to provide moisture to the eyes.
While some ointments may have a slight moisturizing effect, this is not the main reason for using erythromycin ointment in newborns.
If moisture is the primary concern, other products specifically designed to lubricate the eyes would be more appropriate.
Choice B rationale:
Chemical conjunctivitis is typically caused by exposure to irritants such as chlorine in swimming pools or strong chemicals. Erythromycin ointment is not effective in preventing chemical conjunctivitis.
In fact, it could potentially worsen the irritation if used in cases of chemical conjunctivitis.
If chemical conjunctivitis is suspected, flushing the eyes with water or saline solution and seeking medical attention would be the appropriate course of action.
Choice D rationale:
Erythromycin ointment is an antibiotic, but it is not typically used to treat active infections in newborns.
If a newborn has a suspected eye infection, a healthcare provider would likely prescribe a different antibiotic eye drop or ointment that is more effective in treating the specific infection.
However, erythromycin ointment can be used as a prophylactic measure to prevent eye infections, which is why it is commonly administered to newborns shortly after birth.
Choice C rationale:
Erythromycin ointment is primarily used to prevent eye infections in newborns.
It is effective against a variety of bacteria that can cause conjunctivitis, including Neisseria gonorrhoeae (the bacteria that causes gonorrhea) and Chlamydia trachomatis (the bacteria that causes chlamydia).
These bacteria can be passed from the mother to the baby during childbirth, and if left untreated, they can cause serious eye infections that can lead to vision loss.
By applying erythromycin ointment to the newborn's eyes shortly after birth, the risk of these infections can be significantly reduced.
Whether you are a student looking to ace your exams or a practicing nurse seeking to enhance your expertise , our nursing education contents will empower you with the confidence and competence to make a difference in the lives of patients and become a respected leader in the healthcare field.
Visit Naxlex, invest in your future and unlock endless possibilities with our unparalleled nursing education contents today