a particular pulse volume is normal, small or large. It is advisable to feel your own pulse simultaneously and develop a habit of making a decision about the volume of the patient's pulse.
A large volume pulse suggests hypertension or diastolic overload (e.g. aortic or mitral incompetence, patent ductus arteriosus, severe anaemia, fever, thyro-toxicosis, etc.). A small volume pulse is usually associated with low output states such as mitral or aortic stenosis and any condition with blood pressure.
Character. The character of a pulse is the entire waveform as felt by the examining fingers. This is better appreciated by feeling the brachial pulse with the thumb; the arm of the patient should be kept straight and your thumb should gently press the artery against the bone until the entire upstroke is absorbed into the pulp of the thumb. This method should be practiced as it can be quite useful in detecting the slow rising.pulse of aortic stenosis, and bisferiens pulse of mixed aortic valve disease and severe aortic incompetence.
An exaggerated upstroke, or a bounding pulse, may be felt in patients with elevated stroke output (mitral regurgitation, ventricular septal defect, high fever), sympathetic overactivity (thyrotoxicosis), and in patients with rigid, sclerotic aorta. A slow upstroke (pulsus tardus) is felt in cases of left ventricular outflow obstruction, and may be associated with a thrill felt over the carotids (carotid shudder).
A large volume pulse may have a collapsing character which can be detected by lifting the arm of the patient, with the four fingers of your one hand placed firmly on his wrist, and the palm of your other handplaced over the brachial artery. A collapsing (Corrigan's) pulse will impart a flick across your fingers on both hands, and suggests a large upstroke (due to diastolic overload) and quick downstroke due to a runoff either at the aorta valve (aortic incompetence) or from the aorta into the left pulmonary artery (patent ductus arteriosus). It is the change of character on lifting the arm and not simply its easy palpability that is specific to a collapsing pulse. Corrigan's pulse can be seen and felt in the neck over the carotid artery.
Pulsus bisferiens with two peaks (the tidal and percussion waves) can be felt over the carotids, but it is best felt over the peripheral pulses such as the radials, brachials and
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femoralis in some patients with combined aortic valve disease and severe aortic regurgitation.
Pulsus alternans (equally spaced and alternating large and small beats) is a sign of left ventricular depression. It must be distinguished from pulsus bigeminus in which a premature ventricular beat occurs after every normal beat. This ectopic beat feels weak at the wrist and is easily confused with the weak beat of pulsus alternans, but in the latter the rhythm is regular whereas in the former the weaker beat always follows the short interval.
Pulsus paradoxus - the pulse volume normally decreases during inspiration, but this decrease is exaggerated when there is a reduced left ventricular stroke volume (cardiac tamponade, constrictive pericarditis), and transmission of negative intrathoracic pressure to the aorta (severe bronchial asthma, emphysema). Thus, the application of the term pulsus paradoxus, to a greater than normal decline in systolic arterial pressure (10 mm Hg or more) during inspiration, is wrong but it has the advantage of common and long usage. Although both thepulsus alternans and paradoxus can be appreciated at the radial pulse, they are easily recognized on sphygmomanometry.
Tension. An estimation of tension (systolic pressure within the artery) can be obtained by compressing the brachial artery gradually until the radial pulse disappears. The force required to obliterate the brachial arterial pulse can be given by a figure which should approximate to the measured systolic pressure. The difference between the two gets smaller with experience.
Other pulses must be examined now if the cardiovascular system alone is being examined, but the task can be deferred till the examination of the nervous system when it is convenient to feel for the pulses as well as test the tendon reflexes in the legs. You should decide upon a routine and stick to it.
The other radial artery should be palpated simultaneously to compare the volume and tension in both radials. The femoral artery should be located in the inguinal region and felt to both sides, and if its volume is suspected to be low then it should be felt simultaneously with the radial to look for the radiofemoral delay. In obstructive lesions
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of the aorta (coarctation of the aorta; atheroma, dissection, compression by a tumour) the femoral pulse, which is normally ahead of the radial, is delayed and reduced in volume.
Of the other pulses the popliteal can be difficult to feel, particularly when it is important (namely in peripheral vascular insufficiency) to decide whether it is palpable and of normal volume. With the knee joint semiflexed the popliteal fossa should be palpated with both hands. In difficult cases the palpable pulse may be felt in the prone position. The posterior tibial and the dorsalis pedis pulses are comparatively easier to feel in their appropriate places.
The carotid pulse because of its proximity to the heart can be very informative and, as an extension of the outflow tract, reflects faithfully the events at and below the aortic valve. It can be felt inside the sterno-mastoid muscle with the thumb. The anacrotic pulse can be appreciated by the pulp and the collapsing pulse can be felt as well by following movements of the thumb (Corrigan's sign).
The waveform of the carotid pulse may be difficult to appreciate in some patients with a large adipose or muscular bulk. For this reason it is important to cultivate the habit of palpating the brachial pulse.
Popov-Saveliev's sign (Saveliev N.A., Russian therapist; Popov V.O. - Russian physician) - a weakening of the pulse wave in the left radial artery, especially when lying on the left side (a sign of stenosis of the left atrioventricular opening).
Blood pressure
This important task should be undertaken towards the end of the examination, or at least after 15 minutes rest, when the patient is more likely to be relaxed and accustomed to the environment and examination. Blood pressure is measured with a stethoscope and a sphygmomanometer. The width of the cuff should be about 40% of the circumference of the limb used for determining the blood pressure. The standard size, a 14 cm wide cuff, is used for adult with an arm of average size. The cuff width should be 7 cm for young children, and 22 cm for obese and heavily built subjects. The mercury manometer should be kept at a level corresponding to the heart of the patient to rule out the influence of gravity.
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The cuff should be wrapped firmly around the upper arm and air pumped while the brachial or radial pulse is felt. As the pressure in the cuff exceeds the systolic pressure within the brachial artery the pulse becomes impalpable. This pressure should be noted and the cuff deflated.
Next the bell of the stethoscope should be placed lightly over the brachial artery in the antecubital fossa and the above procedure repeated. After the pressure has reached the previously noted level, the cuff should be deflated gradually. The passage of blood past the decreasing obstruction creates a series of sounds (named after Korotkoff, a naval surgeon who first described them) which are audible through the stethoscope. The first loud sound (phase I) approximates to systolic pressure. As the pressure in the cuff is further lowered, the sounds first become softer (phase II), then
louder (phase III), as the volume of blood flow through the constricted artery increases. The sounds become muffled (phase IV) when the arterial caliber increases and the arterial diastolic pressure approaches. The point of disappearance of the Korotkoff sounds (phase V) is used to define diastolic pressure. It is a good practice to record the pressure both at phase IV and phase V. In aortic regurgitation and pregnancy the disappearance point may be very low when phase IV is much closer to the diastolic pressure.
The systolic pressure should always be measured first by palpation, since in some patients with very high blood pressure the Korotkoff sounds may disappear then reappear again as the cuff pressure is lowered. This phenomena is called the auscultatory silent gap.
The blood pressure should be measured in both arms if the pulse is weaker on one side, or if you suspect vertebrobasilar insufficiency with subclavian steal. In patients with orthostatic hypotension, the measurements should be taken both in the supine and the erect positions. In patients suspected of having coarctation or atheromatous disease of the aorta, blood pressure should be measured in the arm and in the thigh where the arterial systolic pressure, which is usually about 20 mm Hg higher than in the arm, may be lower. The cuff should be applied to the thigh in the prone position, and auscultation should be carried out over the popliteal fossa.
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In pulsus alternans, the systolic pressure may vary by more than 10 mm Hg in alternate beats. This discrepancy can be recognized by alteration in the intensity of the Korotkoff sounds. In pulsus paradoxus, the peak systolic pressure during expiration may be higher by 10 mm Hg or more than the corresponding pressure during the entire cycle of respiration.
Hill's sign (Hill L., 1866-1952, English physiologist, Nobel Prize winner in Physiology). Hill's sign is an increase of existing and normal difference of systolic blood pressure on the arms and legs.
The normal systolic blood pressure on the legs (as measured by Korotkoff method) is higher than on the arms, but not more than 10-15 mm Hg. This is due to feebly marked augmentation (amplification) phenomenon, i.e. summing of the amplitudes of the incoming and reflected waves (forming the so-called «standing wave») in the lower limbs due to greater distance from the heart to the lower extremities in comparison with the upper limbs. It should be noted that during direct intravascular measurement, blood pressure on the legs is not higher than on the arms.
Hill's sign occurs in hyperkinetic conditions due to even more enhancement (further augmentation) of blood wave at high stroke volume, when the value of «standing waves» (the «tsunami»1 effect) can be significantly increased. This occurs in case of severe aortic insufficiency, hyperthyroidism and other hyperkinetic states.
CIRCULATORY FAILURE
Circulatory failure is an extremely common problem with an incidence of 2% at age 50 years, rising to 10% at age 80 years. There is still a high mortality: 10—30% per year. Circulatory failure occurs when an adequate blood flow to the tissues cannot be maintained. This maybe caused by inadequate cardiac output (heart failure) or by a markedly reduced intravascular volume, for example after major haemorrhage, acute dehydration or in septicaemic shock (vascular failure).
Heart failure (congestive heart failure): Symptomatic myocardial dysfunction resulting in a characteristic pattern of hemodynamic, renal, and neurohormonal responses.
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