Pulse rate

“ The pulse pressure is subject to wide fluctuations but as a rule for any one normal heart it remains fairly constant as the rate varies. In a rapidly beating heart the diastole is short and the diastolic pressure rises. If the systolic pressure does not also rise, as in a normal heart following exercise, we will say, the pulse pressure falls. We know that when the pulse rate is constant, vasodilatation causes a fall in diastolic pressure and a rise in pulse pressure. On the contrary, vasoconstriction causes a rise in diastolic pressure and a fall in pulse pressure. ”

“ The distinguishing characters of the pulse are diminished force and volume, and a tone so much impaired that slight causes produce extreme variations in its rate and rhythm. If the disease be a fever, as is by some maintained, then it is the only fever in which the pulse-rate is often far below the normal, and at the same time neither full nor tense, unless transiently and in altogether exceptional cases. In no other disease attended with inflammation do the rate and quality of the pulse vary so greatly within short intervals. ”

“ He does not believe that the estimate of the pressure pulse is indicative of cardiac strength. He believes that the important factors in the estimation of the circulatory strength are the systolic pressure, which shows the power of the left ventricle, the diastolic pressure, which shows the intravascular tension during diastole as well as the peripheral resistance, and the pulse rate, which designates the number of times the heart must contract during a minute to maintain the proper flow of blood. ”

“ The pulse is beating at the rate of about 72 per minute or say once in a second. The frequency of the beat is not always constant but fluctuates under excitation or depression.
The normal blood-pressure and its induced changes can also be recorded by elaborate contrivances. The record thrown on the screen shows the change in the blood pressure by alternate stimulation and partial inhibition of the activity of the heart-pump. Under normal conditions the up and down-strokes of each constituent pulse are equal. During increasing
Record of falling and rising blood pressure. ”

“ With a sound heart the blood pressure will be higher and the pulse slower than the previous record taken. If the blood pressure and pulse beat are not changed, it shows that the heart is not quite normal, but not actually incompetent. When the blood pressure is lower and the pulse accelerated, he believes that there is distinct functional disturbance of the heart and loss of power, relatively to the change in pressure and the increase of the pulse rate. He further believes that a heart showing this kind of weakness should, if possible, not be subjected to general anesthesia. ”

“ Seventy-five percent of 180 yields a pulse rate of 135 beats per minute. If you are 40, you would want to run for an hour so as to maintain a pulse rate of 135 beats per minute during your run. By way of encouragement, you may want to know that 75 percent of a person's maximum heart rate represents, for almost everyone, a slow, easy jog. ”

“ There may be a ratio of auricular contractions to ventricular contractions, according to Fulton, of 2:1, 3:1, 4:1 and 5:1, the 2:1 ratio being most common.
Of course it is generally understood that children have a higher pulse rate than adults; that women normally have a higher pulse rate than men at the same age; that strenuous muscular exercise, frequently repeated, without cardiac tire while causing the pulse to be rapid at the time, slows the pulse during the interim of such exercise and may gradually cause a more or less permanent slow pulse. ”

“ If below 60, there is considerable lack of vital power, requiring rest and food to restore it.
In adults the rate for males is from 70 to 75 beats per minute, and for females 75 to 80. In infants the healthy pulse may be at birth 130 to 140 per minute, diminishing with increase of age. In the case of any child under five and over one year, if the pulse beats, say, 108 in the minute, it is too fast. The pulse of an adult may go down as low as 60 or even 50 per minute, but there is then something wrong. ”

“ The rate of the pulse is modified by age, fatigue, posture, exercise, stimulants, disease, and many other circumstances. At birth the rate is about 140 times a minute, in early infancy, 120 or upwards, in the healthy adult between 65 and 75, the most common number being 72. In the same individual, the pulse is quicker when standing than when lying down, is quickened by excitement, is faster in the morning, and is slowest at midnight. ”

“ Daily aerobic exercise will strengthen the heart, gradually slowing the heart's resting pulse rate, indicating that the heart has become much stronger, pumping more blood with each pulse. As the resting pulse drops the exercising heartbeat can be increased to double the resting rate. ”

“ Very important is the relation between the pulse and respiration. Normally, four pulsations occur to each respiratory act. In pulmonary affections, while the circulation is often disturbed pari passu with the breathing, it may be quite otherwise. Great acceleration of the rate of breathing, with little increase in the rapidity of the pulse, should lead us to suspect disease involving the respiratory organs. Conversely, a much hurried or otherwise perturbed pulse, with little or no change in the breathing, points toward the heart as either functionally or organically the seat of disorder. ”

“ The average number of pulsations in a healthy adult is from 70 to 75, but there are some persons who, when they are quite well have a pulse of 80 or 90 to the minute, and 207there are others in whom it seldom rises above 60. It is usually more rapid in women than in men, is much more frequent in early life than in old age, and the average rate in a healthy child is 120.
In disease, the pulse may acquire a great degree of frequency. ”

“ An increase not accounted for by one of the above reasons usually means fever, a rise of 6 beats in pulse usually being equivalent to a rise of 1 degree. Often more important than the rate, however, is the quality of the pulse. ”

“ It should be remembered that athletes have slow pulse, and the severity of their condition must not be interpreted by the rate of the pulse. Even with high fever the pulse of an athlete may be slow.
Not enough investigations have been made of the rate of the pulse during sleep under various conditions. ”

“ In further experiments it was found that the rate of pulse propagation is not affected directly by the manner of the heart's action, whether it beats quickly, launching a sharp wave, or slowly, sending a sloping wave; that, other things being equal, the pulse-wave travels more slowly along large, and faster along small, arteries; that mere distance from the heart neither accelerates nor retards the velocity of the beginnings of pulse waves, while the modifying influence of different pressures is small at most ”

“ The call of an actively functionating organ or group of organs causes a widening of a more or less extensive area, and the velocity necessarily varies. In states of great relaxation of the vessels there may be a capillary pulse. In order to force blood at the same rate through dilated vessels as through normal vessels, there must be more blood or there must be a more rapid contraction of the central pump. What actually happens, as a rule, is an increase in the rate of the heart beat. ”

“ For instance, the pulse-wave travels at the rate of about 30 feet a second, and takes about 1/10 of a second to reach the wrist, while the blood itself is from 3 to 5 seconds in reaching the same place. ”

“ Usually the pulse beats four times during one respiration, but both in health and disease its frequency may be accelerated or retarded. In adults, there are from sixty-five to seventy-five beats in a minute, and yet in a few instances we have found, in health, only forty pulsations per minute. But when the heart beats from one hundred and twenty to one hundred and forty times a minute, there is reason to apprehend danger, and the case should receive the careful attention of a physician.
Irregularity of the pulse may be caused by disease of the brain, heart, stomach, or liver ”

“ The pulse travels about 20 times as fast as the blood flows in the arteries (7–8 metres per second) . By feeling the pulse we can tell whether the heart-beat is frequent, quick, strong, regular, &c., and whether the wall of the artery is normal and the pressure in the arteries high or low. Frequency expresses the number per minute, quickness the duration of a single beat. The pulse is a most important guide to the physician. The pulse can be registered graphically by means of a sphygmograph. ”

“ When any difficulty occurs in determining the weak pulse from the strong one, it may generally be assisted by counting its frequency. For when an adult patient lies horizontally in a cool room, and is not hurried or alarmed by the approach of his physician, nor stimulated by wine or opium, the strong pulse seldom exceeds 118 or 120 in a minute; and the weak pulse is generally not much below 130, and often much above that number. ”

“ It has been already observed, that the pulsations of the artery which we feel at the wrist, are occasioned by its alternate dilatations and contractions, which vary according to the strength and regularity of the circulation, which is liable to be affected by the smallest changes in the state of health. Hence physicians make use of the pulse as a criterion whereby to judge of the health of the body. And we may observe that there are few more certain characteristics of the state of the body than the pulse ”

“ The pulse is generally about 120 when in bed and in the morning; and is increased to 134, or more, when the patient sits up, or in the evening paroxysm. The pulse of all very weak patients increases in frequency when they sit up; because the expenditure of sensorial power necessary to preserve an erect posture deducts so much from their general strength; and hence the pulse becomes weaker, and in consequence quicker. See Sect. XII. 1. 4.
In this fever time must be allowed for the absorption of the matter. ”

“ In other cases, on the contrary, the pulse continues frequent during convalescence, or readily becomes so after a slight exertion or excitement of any kind. A slow pulse during convalescence has been in my experience most frequent in men whose health previous to the attack was good, and a frequent pulse in women and delicate men. If the convalescence is retarded by a complication, the pulse will maintain its frequency until this is removed. ”

“ Careful estimation of the blood pressure in surgical cases has, at times, great value. In all surgical diseases the most important fact to know is not the systolic pressure, but the pulse pressure. If the pulse pressure keeps within the range of normal, does not drop much below 30 mm. in an adult, then so far as we can tell the circulation is being carried on. When the systolic pressure is gradually falling and the diastolic remains the same, the circulation is failing and unless the pulse pressure can be established again the patient will die. ”

“ Finally, that the pulses of the arteries are due to the impulses of the blood from the left ventricle, may be illustrated by blowing into a glove, when the whole of the fingers will be found to become distended at one and the same time, and in their tension to bear some resemblance to the pulse. For in the ratio of the tension is the pulse of the heart, fuller, stronger, and more frequent as that acts more vigorously, still preserving the rhythm and volume, and order of the heart's contractions. ”

“ Each case demands careful study. In no [p. 349] other disease is so much discretion and judgment required in the administration of stimulants as in croupous pneumonia. The pulse, being the indicator of the condition of the heart, must be carefully studied. A frequent, feeble, irregular, or intermittent pulse always indicates heart-insufficiency. The quantity of stimulants to be administered in any case must be determined by their effect upon the pulse. ”

“ FACTORS INCREASING THE BLOOD PRESSURE With normal heart and arteries, exertion and exercise should increase the systolic pressure, and generally somewhat increase the diastolic pressure. The pressure pulse should therefore be greater. When there is circulatory defect or abnormal blood pressure, exercise may not increase the systolic pressure, and the pressure pulse may grow smaller. As a working rule it should be noted that the diastolic pressure is not as much influenced by physiologic factors or the varying conditions of normal life as is the systolic pressure. ”

“ Irregularity of the pulse generally indicates disease, and there are two varieties of it. In most instances of irregular pulse, succeeding beats differ in length, force and character; in the other variety a pulsation is from time to time left out; the pulse is said to intermit. ”

“ A natural pulse is always, per se, a good sign. Yet in the history of a disease usually so well marked as yellow fever some fatal cases have been recorded (walking cases) in which the pulse, almost to the last, was natural.
Strength of the pulse, to a certain degree, belongs to it normally. But this is often exaggerated, and we may have the strong, hard, full, perhaps bounding, pulse of an inflammatory affection (of the brain, for example, or of the joints in acute rheumatism) in a person of vigor. ”

“ For, not only is experience in opposition to this idea, though Galen endeavours to explain it away, when we see that with excessive repletion the pulse beats more forcibly, whilst the respiration is diminished in amount; but in young persons the pulse is quick, whilst respiration is slow. So is it also in alarm, and amidst care, and under anxiety of mind; sometimes, too, in fevers, the pulse is rapid, but the respiration is slower than usual. ”