释义 |
DictionarySeemassagecarotid sinus massage
Carotid Sinus Massage DefinitionCarotid sinus massage involves rubbing the large part of the arterial wall at the point where the common carotid artery, located in the neck, divides into its two main branches.PurposeSinus, in this case, means an area in a blood vessel that is bigger than the rest of the vessel. This is a normal dilation of the vessel. Located in the neck just below the angle of the jaw, the carotid sinus sits above the point where the carotid artery divides into its two main branches. Rubbing the carotid sinus stimulates an area in the artery wall that contains nerve endings. These nerves respond to changes in blood pressure and are capable of slowing the heart rate. The response to this simple procedure often slows a rapid heart rate (for example, atrial flutter or atrial tachycardia) and can provide important diagnostic information to the physician.DescriptionThe patient will be asked to lie down, with the neck fully extended and the head turned away from the side being massaged. While watching an electrocardiogram monitor, the doctor will gently touch the carotid sinus. If there is no change in the heart rate on the monitor, the pressure is applied more firmly with a gentle rotating motion. After massaging one side of the neck, the massage will be repeated on the other side. Both sides of the neck are never massaged at the same time.PreparationNo special preparation is needed for carotid sinus massage.AftercareNo aftercare is required.RisksThe physician must be sure there is no evidence of blockage in the carotid artery before performing the procedure. Massage in a blocked area might cause a clot to break loose and cause a stroke.Normal resultsCarotid sinus massage will slow the heart rate during episodes of atrial flutter, fibrillation, and some tachycardias. It has been known to stop the arrhythmia completely. If the procedure is being done to help diagnose angina pectoris, massaging the carotid sinus may make the discomfort go away.ResourcesBooksMcGood, Michael D., editor. Mayo Clinic Heart Book: The Ultimate Guide to Heart Health. New York: William Morrow and Co., Inc., 1993.Key termsAngina pectoris — Chest pain usually caused by a lack of oxygen in the heart muscle.Arrhythmia — Any deviation from a normal heart beat.Atrial fibrillation — A condition in which the upper chamber of the heart quivers instead of pumping in an organized way.Atrial flutter — Rapid, inefficient contraction of the upper chamber of the heart.Carotid artery — One of the major arteries supplying blood to the head and neck.Tachycardia — A rapid heart beat, usually over 100 beats per minute.ca·rot·id si·nus mas·sage (kă-rot'id sī'nŭs mă-sahzh') Therapeutic manipulation of the carotid sinus in treatment of supraventricular tachycardia. carotid sinus massage Abbreviation: CSM Application of pressure to and rubbing of the carotid artery to slow a supraventricular tachycardia (SVT). This is one of the maneuvers sometimes used before drug therapy for SVT. CAUTION!CSM should not be performed on patients with known atherosclerosis of the carotid arteries, on patients who are elderly or of advanced middle age, or on patients with carotid bruits. Stroke may result from the procedure, esp. if small emboli break off from the carotid artery during the massage.Patient careA patient with narrow complex tachycardia (QRS duration of less than 0.12 sec) is placed in a supine position and given supplementary oxygen. An intravenous catheter is inserted, and an automated blood pressure cuff is applied. Electrodes are placed on the chest to monitor heart rate and rhythm, and an oximeter is positioned on a finger or earlobe. The carotid arteries are examined for bruits. If any are present, the procedure should not be performed. The carotid sinus is located approximately 2 cm above the thyroid cartilage on the nondominant artery (usually the right carotid artery). Firm pressure is applied to the artery in a back and forth motion for about 5 seconds. The heart rate and rhythm are carefully observed during the procedure. See also: massage |