What is the initial temporizing measure for hypotension following the onset of 3rd degree heart block?

The initial temporizing measure for hypotension due to 3rd degree heart block is transcutaneous pacing. In this condition, there is a complete dissociation between the atria and ventricles, leading to ineffective heart contractions and resulting in low cardiac output and hypotension. Transcutaneous pacing provides immediate electrical stimulation to the heart, temporarily overriding the block and re-establishing an adequate heart rate.

While fluid resuscitation and IV fluids may be beneficial in cases of hypovolemia-induced hypotension, they do not directly address the underlying issue of the heart block. Medications may be considered as part of management, but in the acute setting where immediate reversal of the cardiac issue is necessary, transcutaneous pacing is the most effective initial response. This approach stabilizes the patient while further interventions can be planned.