A nurse is caring for a client who has a pulmonary embolism and has a new prescription for enoxaparin 1.5 mg/kg/dose subcutaneously every 12 hours. The client weighs 245 lbs. How many mg should the nurse administer per dose? (Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)

Choice A Reason: This choice is incorrect because flatened neck veins are not a sign of cardiac tamponade. Cardiac tamponade is a condition in which fluid accumulates in the pericardial sac that surrounds the heart, causing compression and impaired filling of the heart chambers. This leads to reduced cardiac output and hypotension. One of the manifestations of cardiac tamponade is distended neck veins due to increased venous pressure and impaired venous return.

Choice B Reason: This choice is incorrect because bradycardia is not a sign of cardiac tamponade. Bradycardia is a condition in which the heart rate is slower than normal (less than 60 beats per minute). It may be caused by various factors such as vagal stimulation, medication side effects, hypothyroidism, or sinus node dysfunction. It may cause symptoms such as fatigue, dizziness, or syncope, but it does not indicate cardiac tamponade.

Choice C Reason: This choice is incorrect because sudden lethargy is not a specific sign of cardiac tamponade. Lethargy is a condition in which the person feels tired, sluggish, or drowsy. It may be caused by various factors such as sleep deprivation, depression, infection, anemia, or hypoglycemia. It may affect the person's mental and physical performance, but it does not indicate cardiac tamponade.

Choice D Reason: This choice is correct because muffled heart sounds are a sign of cardiac tamponade. Muffled heart sounds are heart sounds that are fainter or softer than normal due to reduced transmission of sound waves through fluid-filled pericardial sac. They may indicate that the heart function is compromised by cardiac tamponade and require immediate intervention such as pericardiocentesis (removal of fluid from pericardial sac).

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.