Author Question: Which of the following information best helps to distinguish chronic hypercapnic respiratory failure ... (Read 46 times)

gonzo233 · **on:** Jul 16, 2018

Which of the following information best helps to distinguish chronic hypercapnic respiratory failure from acute hypercapnic respiratory failure?

a. Long-standing dyspnea that worsens on exertion
b. Forced expiratory volume in 1 sec to forced vital capacity ratio (FEV1/FVC) of less than 75 predicted
c. Kidneys retaining bicarbonate to elevate the blood pH
d. Physical signs of hypoxemia, such as cya-nosis and clubbing

Question 2

Which of the following are associated with hypercapnic respiratory failure due to respiratory muscle weakness or fatigue?

1. Hyperthyroidism
2. Myasthenia gravis
3. Amyotrophic lateral sclerosis
4. Guillain-Barr syndrome
a. 1 and 3 only
b. 1, 2, and 3 only
c. 3 and 4 only
d. 2, 3, and 4 only

cloudre37 · **Reply #1 on:** Jul 16, 2018

Answer to Question 1

ANS: C
Most commonly, chronic hypercapnic respiratory failure accompanying COPD or obesi-ty-hypoventilation syndrome would elicit a renal response by which the kidneys retain bicar-bonate to elevate the blood pH.

Answer to Question 2

ANS: D
Examples include spinal trauma, motor neuron disease where lesions of the anterior horn cells may gradually lead to progressive ventilatory failure (such as in amyotrophic lateral sclerosis, or poliomyelitis), motor nerve disorders (including Guillain-Barr syndrome and Char-cot-Marie-Tooth disease), disorders of the neuromuscular junction (such myasthenia gravis and botulism), and muscular diseases (including muscular dystrophy, myositis, critical care myopathy, and metabolic disorders).