The primary cause of bronchiolitis is

Correct Answer: D

Rationale: The primary cause of bronchiolitis is Respiratory Syncytial Virus (RSV). RSV is the leading cause of bronchiolitis in infants and young children. It is highly contagious and spreads through respiratory secretions. RSV infects the lining of the small airways in the lungs, leading to inflammation, mucus production, and narrowing of the airways, which are characteristic features of bronchiolitis. Option A, Human metapneumovirus, is not the primary cause of bronchiolitis. While it can cause respiratory infections in children, RSV is more commonly associated with bronchiolitis. Option B, Parainfluenza viruses, typically cause croup, a viral infection that affects the upper airway, rather than bronchiolitis, which affects the lower airways. Option C, Rhinoviruses, are more commonly associated with the common cold and less likely to cause bronchiolitis compared to RSV. Understanding the primary causative agent of bronchiolitis is crucial for nurses caring for pediatric patients. Recognizing the signs and symptoms of RSV infection, such as cough, wheezing, and respiratory distress, can lead to prompt identification and treatment of bronchiolitis, ultimately improving patient outcomes. Educating parents about preventive measures, such as hand hygiene and avoiding exposure to sick individuals, can also help reduce the spread of RSV and the incidence of bronchiolitis in young children.

Correct Answer: A

Rationale: Blood cultures are an essential diagnostic tool in identifying the bacterial cause of pneumonia in hospitalized children. The correct answer is A) 10% to 20% of bacterial pneumonia. This range represents the typical positivity rate of blood cultures in bacterial pneumonia cases. Blood cultures help identify the specific bacterial pathogen responsible for the infection, guiding appropriate antibiotic therapy. Option B) 20% to 30% is incorrect because blood cultures are generally positive in a lower percentage of cases than this range. Option C) 30% to 40% and Option D) 40% to 50% are also incorrect as they overestimate the positivity rate of blood cultures in bacterial pneumonia cases. Educationally, understanding the diagnostic procedures for pneumonia, such as blood cultures, is crucial for nurses caring for pediatric patients. This knowledge helps in timely and accurate identification of the causative organism, leading to effective treatment and improved patient outcomes. Nurses need to be familiar with the expected positivity rates of diagnostic tests to interpret results correctly and collaborate with healthcare providers in providing optimal care for pediatric patients with pneumonia.

Correct Answer: D

Rationale: The correct answer is D) Cardiac catheterization for the definitive diagnosis of pulmonary arterial hypertension. Pulmonary arterial hypertension (PAH) is a serious condition that requires accurate diagnosis for appropriate management. Cardiac catheterization is considered the gold standard for diagnosing PAH as it directly measures the pressure in the pulmonary arteries and assesses the response to vasodilator medications, which is crucial for determining the severity of the condition and guiding treatment decisions. Option A) ECG is not the definitive diagnostic test for PAH. While an ECG may show signs of right ventricular hypertrophy, it does not provide direct measurements of pulmonary artery pressure. Option B) Echocardiography can provide valuable information about the heart's structure and function, including signs of PAH, but it does not directly measure pulmonary artery pressure like cardiac catheterization. Option C) CXR may show signs of pulmonary hypertension such as enlarged pulmonary arteries or changes in lung vasculature, but it does not provide direct measurements of pulmonary artery pressure needed for a definitive diagnosis of PAH. In an educational context, understanding the diagnostic modalities for PAH is essential for nursing students preparing for the NCLEX exam. This question helps reinforce the importance of cardiac catheterization in diagnosing PAH accurately and highlights the limitations of other diagnostic tests in providing definitive measurements of pulmonary artery pressure. Nurses need to be familiar with these diagnostic procedures to ensure timely and appropriate management of patients with PAH.

Correct Answer: B

Rationale: The correct answer is B) 20%. In Cystic Fibrosis (CF), approximately 20% of patients are born with intestinal obstruction caused by inspissated meconium, known as meconium ileus. This is a key feature of CF due to the thick, sticky mucus that affects various organs in the body, including the intestines. Option A) 10% is incorrect because the prevalence of meconium ileus in CF is higher than 10%. Option C) 30% and Option D) 40% are also incorrect as they overestimate the percentage of CF patients born with meconium ileus. Educationally, understanding the prevalence of meconium ileus in CF is crucial for nurses caring for pediatric patients with this condition. Recognizing this early sign can lead to prompt intervention and management, improving outcomes for these patients. It also highlights the multisystem nature of CF and the importance of a comprehensive approach to care.

Correct Answer: D

Rationale: In this scenario, the most likely diagnosis is choanal atresia (Option D). Choanal atresia is a congenital condition where there is a blockage of the posterior nasal passage, leading to respiratory distress, especially in newborns. In this case, the infant's initial ability to cry vigorously and then sudden onset of cyanosis and respiratory distress point towards a possible airway obstruction, which aligns with choanal atresia. Option A, tracheoesophageal fistula, would typically present with symptoms such as choking, coughing, and respiratory distress immediately after birth due to abnormal connection between the trachea and esophagus. Option B, pneumothorax, would present with sudden onset respiratory distress, but the inability to pass a nasogastric tube is not consistent with this diagnosis. Option C, persistent fetal circulation, would not typically present with sudden respiratory distress and cyanosis after an initial period of normalcy. Educationally, this question highlights the importance of recognizing the signs and symptoms of choanal atresia in newborns, as prompt diagnosis and intervention are critical for the infant's well-being. Understanding common respiratory conditions in newborns is essential for pediatric nurses to provide timely and appropriate care in emergent situations.