Ans. b (Paradoxical respiration). (Ref. Harrison's Principles of Medicine 16th ed., 1589)"RESPIRATORY FAILURE# 4 types of respiratory dysfunctions are- Pump dysfunction (Hypercapnic respiratory failure)- Airway dysfunction- Alveolar dysfunction- Pulmonary vascular dysfunction# Hypercapnic Respiratory Failure- Respiratory failure due to a disease of the muscles used for breathing ("pump or ventilatory apparatus failure") is called hypercapnic respiratory failure. The lungs of these patients are normal.- This type of respiratory failure occurs in patients with neuromuscular diseases such as myasthenia gravis, stroke, cerebral palsy, poliomyelitis, ammyotropic lateral sclerosis, muscular dystrophy, postoperative situations limiting ability to take deep breaths, and in depressant drug overdoses.- Each of these disorders involves a loss or decrease in neuromuscular function, inefficient breathing and limitation to the flow of air into the lungs.- Abdominal paradox which indicates diaphragm fatigue is the 'hallmark' of pump failure.- Other features include presence of wheezing,* VC<10 mL/kg, IF < -20 cm H20, RSBI > 105.- In general, mechanical devices that help move the chest wall help these patients.# Symptoms Of Respiratory Failure- The clinical features of respiratory failure vary widely in individual patients because so many different conditions can lead to this disorder.- There are no physical signs unique to respiratory failure.- At extremely low arterial oxygen (PaO2) levels, patients have rapid heart rates, rapid breathing rates, and they are confused, sweaty, and cyanotic (blue).- Chronically low arterial oxygen makes patients irritable, and elevated carbon dioxide produces headaches and sleepiness.- Difficult, rapid, or laboured breathing (dyspnea) is a consistent symptom in the awake patient.- The functions of the heart and blood vessels are often severely impaired in patients with respiratory failure.