A nurse in the emergency department is caring for a client who was injured in a motor-vehicle crash. The client reports dyspnea and severe pain. The nurse notes that the client's chest moves inward during inspiration and bulges out during expiration. The nurse should identify this finding as which of the following?

Choice A Reason: This choice is incorrect because warm, flushed skin is not a sign of respiratory acidosis. Warm, flushed skin may indicate fever, infection, inflammation, or allergic reaction, but it does not reflect the acid-base imbalance in the blood.

Choice B Reason: This choice is incorrect because hyperactive deep tendon reflexes are not a sign of respiratory acidosis. Hyperactive deep tendon reflexes may indicate hypocalcemia, hyperthyroidism, or spinal cord injury, but they do not reflect the carbon dioxide level in the blood.

Choice C Reason: This choice is incorrect because bounding peripheral pulses are not a sign of respiratory acidosis. Bounding peripheral pulses may indicate increased cardiac output, anxiety, or hyperthyroidism, but they do not reflect the pH level in the blood.

Choice D Reason: This choice is correct because widened QRS complexes are a sign of respiratory acidosis. QRS complexes are the segments on an electrocardiogram (ECG) that represent the depolarization of the ventricles. A normal QRS complex duration is 0.06 to 0.10 seconds, and a widened QRS complex duration is more than 0.12 seconds. A widened QRS complex may indicate hyperkalemia, which is a common complication of kidney failure and respiratory acidosis. Hyperkalemia is a condition in which the serum potassium level is higher than normal (more than 5 mEq/L). It may cause cardiac arrhythmias, muscle weakness, or paralysis.

Choice A Reason: This is incorrect because cognitive impairment that decreases over several months post-injury is more likely to occur in a client who has a diffuse axonal injury, which is a widespread damage to the brain's white mater.

Choice B Reason: This is incorrect because neurologic deficits that increase up to 2 weeks post-injury are more likely to occur in a client who has a subdural hematoma, which is a collection of blood between the dura and the arachnoid membranes.

Choice C Reason: This is incorrect because a change in the level of consciousness that develops over 48 hr is more likely to occur in a client who has an intracerebral hematoma, which is a collection of blood within the brain tissue.

Choice D Reason: This is correct because a lucid period followed by an immediate loss of consciousness is a typical manifestation of an epidural hematoma, which is a collection of blood between the skull and the dura. The lucid period occurs when the initial bleeding stops and the client regains consciousness. The immediate loss of consciousness occurs when the bleeding resumes and causes increased intracranial pressure.