The following drugs cause hypokalaemia:

Correct Answer: C

Rationale: In pediatric cardiovascular nursing, understanding the effects of drugs on electrolyte balance is crucial. The correct answer, option C) Salbutamol for asthma, causes hypokalemia. Salbutamol is a beta-2 adrenergic agonist that can stimulate the Na+/K+ pump, leading to potassium shifting into cells and subsequent hypokalemia. This effect is important to monitor in pediatric patients to prevent cardiac arrhythmias. Option A) Commencement of digoxin for atrial fibrillation is incorrect because digoxin can actually lead to hyperkalemia due to its effects on renal potassium excretion. Option B) ACE inhibitors typically do not cause hypokalemia; instead, they can lead to hyperkalemia due to their mechanism of action on the renin-angiotensin-aldosterone system. Option D) Vitamin B1 for the treatment of pernicious anemia is incorrect as it does not have a direct impact on potassium levels. Understanding the specific effects of medications on electrolytes is essential for safe pediatric pharmacological management, especially in cardiovascular conditions where electrolyte imbalances can have serious consequences on cardiac function.

Correct Answer: B

Rationale: In pediatric cardiovascular nursing, understanding the typical features of Down's syndrome is crucial for providing holistic care to patients. The correct answer, option B) Hypotonia, is a key characteristic of Down's syndrome. Hypotonia, or reduced muscle tone, is commonly observed in individuals with Down's syndrome and can impact their motor development and overall physical abilities. Option A) Brachycephaly refers to a shortened head shape, which is not a typical feature of Down's syndrome. Male infertility, option C), is not a common characteristic associated with Down's syndrome. Option D) Increased a-fetoprotein in amniotic fluid is more indicative of neural tube defects rather than Down's syndrome. Educationally, understanding these distinctions is essential for healthcare professionals working with pediatric patients with Down's syndrome. Recognizing the unique features of this condition can aid in early identification, appropriate interventions, and tailored care planning to optimize outcomes for these individuals.

Correct Answer: D

Rationale: In bronchopulmonary dysplasia (BPD), the correct answer is D) Hyperinflation is an associated finding. BPD is a chronic lung disease that primarily affects premature infants who have been treated with oxygen and mechanical ventilation. Hyperinflation occurs as a result of air trapping in the lungs due to inflammation, scarring, and damage to the tiny air sacs. This leads to increased residual volume and decreased expiratory flow rates. Option A) Lung compliance is increased is incorrect because in BPD, lung compliance is actually decreased due to the fibrotic changes in the lungs. Option B) Bronchial reactivity is increased is incorrect because BPD primarily affects the alveoli and air sacs, leading to respiratory distress and not bronchial reactivity. Option C) Lung function typically improves with age is incorrect as BPD can lead to long-term respiratory complications and lung function deficits that may persist into adulthood. Educationally, understanding the pathophysiology of BPD is crucial for pediatric cardiovascular nurses to provide appropriate care and interventions for infants with this condition. Recognizing the associated findings like hyperinflation can guide treatment strategies and improve outcomes for these vulnerable patients.

Correct Answer: B

Rationale: In Wolff-Parkinson-White (WPW) syndrome, the correct answer is B) Wide QRS complexes occur more frequently than narrow QRS. This is because WPW is characterized by an accessory pathway between the atria and ventricles, leading to early ventricular activation and a delta wave on the ECG, resulting in a widened QRS complex. This finding is a hallmark of WPW syndrome and distinguishes it from other arrhythmias. Option A) The abnormal pathway in WPW is not between the atrial and ventricular myocardium, but rather an accessory pathway bypassing the normal conduction system. Option C) Narrow QRS complexes are not regular in WPW due to the presence of the accessory pathway causing abnormal conduction patterns. Option D) Verapamil is contraindicated in WPW as it can worsen conduction through the accessory pathway, potentially leading to life-threatening arrhythmias like ventricular fibrillation. Understanding the ECG findings in WPW is crucial for nurses caring for pediatric patients with this condition. Recognizing the characteristic wide QRS complexes helps in prompt identification and appropriate management to prevent complications associated with WPW syndrome, such as supraventricular tachycardia. Nurses play a vital role in monitoring these patients, administering correct treatments, and educating families on the signs and symptoms of arrhythmias in WPW syndrome.

Correct Answer: C

Rationale: The correct answer is C) Iron is the stimulant for ferritin production. In the context of body iron stores, iron plays a crucial role in regulating the synthesis of ferritin, a protein that stores iron in a non-toxic form. When iron levels in the body are high, ferritin synthesis increases to store excess iron. Conversely, when iron levels are low, ferritin synthesis decreases to help release stored iron for essential functions. Regarding the incorrect options: A) Serum ferritin is actually a reliable indicator of body iron stores. It correlates well with total body iron levels and is commonly used in clinical practice. B) In a healthy individual, most iron is stored in hemoglobin within red blood cells, not as ferritin. D) Haemosiderin is a form of storage iron that is less readily mobilized compared to ferritin in cases of iron deficiency. In an educational context, understanding the regulation of ferritin production is crucial for healthcare providers, especially in pediatric patients who may be at risk of iron deficiency or overload. This knowledge helps in interpreting laboratory results, making appropriate treatment decisions, and providing patient education on iron balance and supplementation.