Final answer:
Transcutaneous cardiac pacing is indicated for unresponsiveness and absence of a pulse, as it is used to manage serious arrhythmias or cardiac arrest.
Step-by-step explanation:
The correct answer to which indication is appropriate for transcutaneous cardiac pacing is 'c) Unresponsiveness and absence of a pulse.' Transcutaneous cardiac pacing is an emergency procedure used in the event of serious arrhythmias or cardiac arrest where the heart beats too slowly or stops completely. In such cases, immediate pacing is necessary to maintain a sufficient heart rate and ensure cardiac output and perfusion. Conditions such as a mild headache, stable cardiac rhythm, and hypertension are not indications for this invasive intervention. Since tachycardia is a rapid heart rate, and can be associated with conditions like fever, anemia, or hyperthyroidism, it's important that proper diagnosis and treatment be determined for underlying causes rather than immediate pacing, except in life-threatening situations where the heart rate is dangerously low (bradycardia) or absent.