释义 |
DictionarySeepulsecarotid pulse
pulse [puls] 1. pulsation.2. the beat of the heart as felt through the walls of a peripheral artery, such as that felt in the radial artery at the wrist. Other sites for pulse measurement include the side of the neck (carotid artery), the antecubital fossa (brachial artery), the temple (temporal artery), the anterior side of the hip bone (femoral artery), the back of the knee (popliteal artery), and the instep (dorsalis pedis artery). What is felt is not the blood pulsing through the arteries (as is commonly supposed) but a shock wave that travels along the walls of the arteries as the heart contracts. This shock wave is generated by the pounding of the blood as it is ejected from the heart under pressure. It is analogous to the hammering sound heard in steam pipes as the steam is forced into the pipes under pressure. A pulse in the veins is too weak to be felt, although sometimes it is measured by sphygmograph (see below); the tracing obtained is called a phlebogram. The pulse is usually felt just inside the wrist below the thumb by placing two or three fingers lightly upon the radial artery. The examiner's thumb is never used to take a pulse because its own pulse is likely to be confused with that of the patient. Pressure should be light; if the artery is pressed too hard, the pulse will disappear entirely. The number of beats felt in exactly 1 minute is the pulse rate. In taking a pulse, the rate, rhythm, and strength or amplitude of the pulse are noted. The average rate in an adult is between 60 and 100 beats per minute. The rhythm is checked for possible irregularities, which may be an indication of the general condition of the heart and the circulatory system. The amplitude of a pulse can range from totally impalpable to bounding and full; however, such terms are vague and subject to misinterpretation. To provide a more standardized description of pulse amplitude some agencies and hospitals use a scale that provides a more objective evaluation and reporting of the force of a pulse. On such a scale zero would mean that the pulse cannot be felt; +1 would indicate a thready, weak pulse that is difficult to palpate, fades in and out, and is easily obliterated with slight pressure; +2 would be a pulse that requires light palpation but once located would be stronger than a +1; +3 would be considered normal; and a +4 pulse would be one that is strong, bounding, easily palpated, and perhaps hyperactive, and could indicate a pathological condition such as aortic regurgitation. If a pulse is noted to be weaker during inhalation and stronger during exhalation (pulsus paradoxus), this could indicate either greater reduction in the flow of blood to the left ventricle than is normal, as in constrictive pericarditis or effusion" >pericardial effusion, or a grossly exaggerated inspiratory maneuver, as in tracheal obstruction, asthma, or emphysema. An instrument for registering the movements, form, and force of the arterial pulse is called a sphygmograph. The sphygmographic tracing (or pulse tracing) consists of a curve having a sudden rise (primary elevation) followed by a sudden fall, after which there is a gradual descent marked by a number of secondary elevations.Pulses palpated during assessment of the arterial system.abdominal pulse that over the abdominal aorta.alternating pulse one with regular alteration of weak and strong beats without changes in cycle length. Called also pulsus alternans.anacrotic pulse one in which the ascending limb of the tracing shows a transient drop in amplitude, or a notch.anadicrotic pulse one in which the ascending limb of the tracing shows two extra small waves or notches.anatricrotic pulse one in which the ascending limb of the tracing shows three extra small waves or notches.apical pulse the pulse over the apex of the heart, as heard through a stethoscope or palpated.atrial venous pulse (atriovenous pulse) a venous pulse in the neck that has an accentuated a wave during atrial systole, owing to increased force of contraction of the right atrium; a characteristic of tricuspid stenosis.bigeminal pulse one in which two beats occur in rapid succession, the groups of two being separated by a longer interval, usually related to regularly occurring ventricular premature beats. Called also pulsus bigeminus.bisferious pulse pulsus bisferiens.brachial pulse that which is felt over the brachial artery at the inner aspect of the elbow; palpated before taking blood pressure to determine location for the stethoscope.capillary pulse Quincke's pulse.carotid pulse the pulse felt over the carotid artery, which lies between the larynx and the sternocleidomastoid muscle in the neck; frequently used to assess effectiveness of cardiac massage during cardiopulmonary resuscitation. It can be felt by pushing the muscle to the side and pressing against the larynx, or, if the patient is dyspneic, by palpating the pulse at the groove in the muscle.catadicrotic pulse one in which the descending limb of the tracing shows two small notches.catatricrotic pulse one in which the descending limb of the tracing shows three small additional waves or notches.Corrigan's pulse a jerky pulse with full expansion and sudden collapse occurring in regurgitation" >aortic regurgitation; called also water-hammer pulse.dicrotic pulse a pulse characterized by two peaks, the second peak occurring in diastole and being an exaggeration of the wave" >dicrotic wave; called also pulsus bisferiens.dorsalis pedis pulse the pulse felt on the top of the foot, between the first and second metatarsal bones. In 8 to 10 per cent of the population this pulse cannot be detected.entoptic pulse a subjective sensation of seeing a flash of light in the dark with each heart beat.femoral pulse one located where the femoral artery passes through the groin in the femoral triangle.funic pulse the arterial tide in the umbilical cord.hard pulse (high-tension pulse) one with a gradual impulse, long duration, slow subsidence, and a firm state of the artery between beats.jerky pulse one in which the artery is suddenly and markedly distended.paradoxical pulse one that markedly decreases in amplitude during inhalation, as often occurs in constrictive pericarditis.pistol-shot pulse Corrigan's pulse.plateau pulse one that is slowly rising and sustained.popliteal pulse one palpated in the popliteal fossa, most easily detected when the patient is lying prone with the knee flexed about 45 degrees.posterior tibial pulse a pulse felt over the posterior tibial artery just posterior to the ankle bone on the inner aspect of the ankle.quick pulse one that strikes the finger smartly and leaves it quickly; called also pulsus celer.Quincke's pulse alternate blanching and flushing of the skin that may be elicited in several ways, such as by pressing on the end of the nail and observing the nail bed or skin at the root of the nail. It is caused by pulsation of subpapillary arteriolar and venous plexuses and is sometimes seen in aortic insufficiency, although it may occur in normal persons under certain conditions. Called also capillary pulse (because it was formerly thought to be due to pulsations in the capillaries) and Quincke's sign.radial pulse that felt over the radial artery at the wrist.Riegel's pulse one that is diminished during respiration.slow pulse one with less than the usual number of pulsations per minute; called also vagus pulse and pulsus tardus.thready pulse one that is very fine and scarcely perceptible.tricrotic pulse one in which the tracing shows three marked expansions in one beat of the artery.trigeminal pulse one with a pause after every third beat.vagus pulse slow pulse.venous pulse the pulsation over a vein, especially over the right jugular vein.water-hammer pulse Corrigan's pulse.wiry pulse a small, tense pulse.ca·rot·id pulsethe pulse of the carotid arteries in the neck.ca·rot·id pulse (kă-rot'id pŭls) A palpable rhythmic expansion of the common carotid artery in the neck; palpated during adult cardiopulmonary resuscitation. ca·rot·id pulse (kă-rot'id pŭls) A palpable rhythmic expansion of the common carotid artery in the neck; palpated during adult cardiopulmonary resuscitation. |