PVCs can be caused by cardiac ischemia or infarction, increased workload on the heart (eg, exercise, fever, hypervolemia, heart failure, tachycardia), digitalis toxicity, acidosis, or electrolyte imbalances, especially hypokalemia.
Sinus tachycardia occurs when the sinus node creates an impulse at a faster-than-normal rate. Causes include medications that stimulate the sympathetic response (e.g., catecholamines, aminophylline, atropine), stimulants (e.g., caffeine, nicotine), and illicit drugs (e.g., amphetamines, cocaine, Ecstasy).
Avoid caffeinated beverages.
If PACs are infrequent, no medical interventions are necessary. Causes of PACs include caffeine, alcohol, nicotine, stretched atrial myocardium (e.g., as in hypervolemia), anxiety, hypokalemia (low potassium level), hypermetabolic states (e.g., with pregnancy), or atrial ischemia, injury, or infarction. The nurse should instruct the patient to avoid caffeinated beverages.
The nurse is teaching a beginning EKG class to staff nurses. As the nurse begins to discuss the the parts of the EKG complex, one of the students asks what the normal order of conduction through the heart is. The correct response would be which of the following?
a) SA node, AV node, right and left bundle branches, bundle of His, and the Purkinje fibers
b) Sinoatrial (SA) node, atrioventricular (AV) node, bundle of His, right and left bundle branches, and the Purkinje fibers
c) SA node, AV node, bundle of His, the Purkinje fibers, and the right and left bundle branches
d) AV node, SA node, bundle of His, right and left bundle branches, and the Purkinje fibers