The Czermak–Hering test is a vagal maneuver consisting of the application of external digital pressure to the carotid sinus.
[1] The test is performed at the patient's bedside by imposing moderate pressure with the fingers, repeatedly massaging the left or the right carotid arteries.
The Czermak–Hering test is a test for autonomic nervous function (vasovagal response), exerting:[2] Johann Nepomuk Czermak stated that mechanical compression of the carotid artery due to the carotid sinus reflex initiates a stimulus of the heart inhibitory branches of the vagus nerve.
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