Венный пульс у взрослого человека: разновидность, исследование

Венный пульс – это колебание стенок крупных вен, неразрывно связанное с сердечным циклом. В норме этот показатель должен быть отрицательным. При положительных результатах говорят о наличии патологических процессов в клапанах сердца.

Понятие венного пульса

При сокращении сердца колеблются показатели давления в крупных артериях и венах, из-за чего происходит колебание сосудов. Благодаря приборам можно точно зафиксировать эти движения, что позволит оценить состояние сердца и сосудов. Показатели учитывают в процессе диагностики кардиальных патологий.

Определение венозного пульса проводится с помощью флебографии. Его легче зарегистрировать над яремными венами, которые находятся на шее.

Обнаружить наличие пульсовых колебаний в мелких кровеносных сосудах нельзя. Но в крупных венах, которые находятся рядом с сердцем, хорошо обнаруживается пульсация.

Его появление связано с оттоком крови к сердцу, когда желудочки и предсердия расслабляются. Когда эти отделы сокращаются, происходит повышение давления и стенки сосудов пульсируют. Это происходит не только с артериями, но и с венами. Такой пульс может быть положительным и отрицательным.

В первом случае это говорит о нарушении функций трикуспидального клапана, а второе значение является нормой. Характер колебания венозных стенок имеете определенные отличия от артериальных. При этом наблюдается более долгое нарастание пульсовой волны и быстрое спадание, колебания будут вялыми и нерезкими.

Как измерять

Обнаружить этот вид пульса можно по визуальным признакам, с помощью пальпации, его определить не получается. Это связано с тем, что давление крови в венах более низкое, чем в артериях, поэтому напряжение стенок ощутить нельзя.

Венозные сосуды набухают и спадают в процессе тока крови от правого предсердия и обратно.

Если с состоянием здоровья человека все в порядке, то, когда он находится в вертикальном положении, яремные вены заметить нельзя. Они могут переполняться кровью во время повышения давления в грудной клетке.

При этом к правому предсердию кровь поступает в замедленном темпе. Это происходит, когда человек кашляет, натуживается, поет, поднимает тяжести.

Если яремные вены набухли без влияния этих факторов, это говорит о том, что произошел периферический застой крови и ухудшился отток крови от правого желудочка. Это состояние характерно для декомпенсированных пороков сердца, тяжелых патологий легких, при которых нарушается ток крови по легочной артерии.

Измерение пульсации провести вручную невозможно. Показатели определяют с помощью флебограммы.

Типы пульсации вен

Существует три типа венозной пульсации. Обычно наблюдают:

1. Передаточную пульсацию вен. В результате пульсовых колебаний сонной артерии этот процесс распространяется на кожный покров, мышцы шеи, из-за чего происходит движение вен. В норме передаточную пульсацию наблюдают у легко раздражающихся людей, при чрезмерных эмоциональных напряжениях, после физических нагрузок. Обычно этот вид наблюдается, если человек страдает гипертензией или приобретенным пороком сердца.
2. Дыхательную пульсацию. Если со здоровьем проблем нет, то этого быть не должно. Данную проблему диагностируют, когда человек страдает заболеваниями, сопровождающимися повышением давления в грудной клетке. Подобные процессы связаны с эмфизематозными изменениями в легочной ткани, то есть с ее повышенной воздушностью. Также дыхательную пульсацию обнаруживают, если система кровообращения перенасыщена кровью у людей, страдающих бронхиальной астмой, плевритом, пневмотораксом. Это зависит от вдоха и выдоха, а также от стадии развития патологического процесса. Когда человек делает вдох, происходит уменьшение объема венозной крови, так как наблюдается пассивное наполнение правого предсердия и появление отрицательного давления в грудной клетке. Выдох сопровождается расширением сосудов, потому что отток крови не происходит.

Выделяют и третий вид пульсации, который называют сердечным пульсом. Он, в свою очередь, делиться на два вида:

1. Отрицательный венный пульс. Если прилечь и легонько сдавить вену, то пульсации наблюдаться не будет. Это считается нормальным явлением. Отрицательным венным пульсом называют конструкцию или сжатие венозных сосудов. Это происходит во время сокращений желудочков и нагнетания крови в артерии. При этом кровь из вены направляется к предсердию под отрицательным давлением торакальной клетки. Происходит уменьшение ее объема. Если состояние организма в норме, при нахождении в горизонтальном положении одновременно сокращаются желудочки и сжимаются яремные вены области над ключицей. Это вполне нормальное явление, которое не говорит о патологических процессах в организме. Встретить отрицательную пульсацию можно на больших сосудах, которые располагаются рядом с сердцем.
2. Положительный венный пульс. При отсутствии проблем со здоровьем этого явления быть не должно. Это происходит, когда яремные вены значительно расширяются при сокращении желудочков. Плюсовую пульсацию обнаруживают при серьезных патологиях. Обычно это явление характерно для приобретенного порока сердца вроде патологических процессов в трехстворчатом клапане. При этом не происходит его полное закрытие во время систолической фазы. Так как створки не закрыты, возникает попадание крови из желудочков в полость предсердий. Из предсердия она распространяется на большой круг кровообращения и становится причиной развития застойных процессов и стаза. О подобной проблеме можно узнать по отеку и болезненным ощущениям в области правого подреберья, накоплению жидкости в брюшной полости, пожелтению кожного покрова и слизистых оболочек.

Если появились такие симптомы, необходимо срочно посетить специалиста, так как эта проблема представляет серьезную опасность для жизни человека. Врач назначит обследование и проведет лечение.

90000 Novel Diagnostic Algorithm for the Floating and Sunken Pulse Qualities and Its Clinical Test 90001 90002 We propose a novel classification algorithm for the floating pulse and the sunken pulse using a newly defined coefficient (). To examine the validity of the proposed algorithm, we carried out a clinical test in which 12 oriental medical doctors made pairwise diagnoses on the pulses of volunteering subjects. 169 subjects were simultaneously diagnosed by paired doctors, and the diagnoses in 121 subjects were concordant, yielding an accuracy of 72% and a Matthews correlation coefficient of 0.42, which indicates reasonable agreement between doctors. Two sample 90003 T 90004 -tests showed that subjects in the sunken pulse group had significantly higher BMI and () than those in the floating pulse group. The pulse classification by the algorithm converged with the diagnoses of paired doctors with an accuracy up to 69%. With these results, we confirm the validity of the novel classification algorithm for the floating and sunken pulses. 90005 90006 1. Introduction 90007 90002 Pulse diagnosis is one of the four important diagnostic methods in oriental medicine, which are inspection, listening and smelling, inquiring, and palpation [1-4].The primary site for pulse diagnosis is the radial artery placed on both wrists. To make a pulse diagnosis, oriental medical doctors (OMDs) divide the terminal region of the radial artery into three adjacent intervals of Chon, Gwan, and Cheok, and use index, middle, and ring fingers on each palpating position. By pressing with these fingers with varying pressure simultaneously or sequentially, doctors determine characteristic pulse qualities. By analyzing the pulse qualities, primarily, doctors obtain information on balance in health and illness or subtle changes in homeostasis [3].90005 90002 Pulse diagnosis requires sophisticated palpation techniques and interpretation on the pulse qualities demands enduring efforts with many clinical trials and case studies. For this reason, experiential bias and subjective judgments remain difficult to avoid. To overcome technical difficulties, to answer doubts and skepticism on its clinical validity, and to go beyond its current state of the art, it is necessary to develop objective techniques for pulse-taking using standardized protocols and quantitative definitions of the pulse qualities in terms of a few measureable physical parameters [5-7].90005 90002 To quantify and standardize pulse diagnosis, it is essential to develop palpation devices that provide objective pulse signals as a function of the hold-down pressure, and to develop classification algorithms of the pulse qualities by analyzing the measured pulses. At the same time, the validity and efficiency of pulse diagnosis need to be verified clinically by objective methods. Thus far, some progress has been made on the quantification and standardization of pulse diagnosis. For example, pulse devices equipped with arrays of piezoresistive pressure sensors have been developed.In addition, clinical data have been collected by pulse devices and it has been analyzed by statistical methods. Studies on the fundamental aspects such as the blood flow dynamics along the radial artery and classifications of pulse waveforms are currently under investigation [8-18]. 90005 90002 Pulse-taking devices should be able to measure pulse waveforms for several different steps of hold-down pressure, and it should be able to record the spatial distribution of the pulse strength along the axis of the radial artery and in its cross-section [5].With a pulse-taking device which supplies the above-described quantities with guaranteed intrarater reliability (repeatability) and interrater reliability (reproducibility), we can obtain some principal characteristics of the pulse such as the level of the depth, width, length, and strength of the pulse, as well as the speed or rate of the pulse. As there are some literature studies which reinterpreted the pulse qualities in the classic textbooks in terms of these measurable quantities [6, 7], a desirable direction to develop classification algorithms for the pulse qualities is to understand a pulse by simple physical quantities.90005 90002 For developing a reliable classification algorithm for the pulse qualities, the algorithm needs to be validated by a clinical test with a relevant protocol. The pulse-taking device used should have guaranteed repeatability and reproducibility, and the pulse qualities determined by the algorithm should be tested for consistency with the OMDs ‘diagnoses. As a first step towards developing reliable classification algorithms, in this work, we introduce a novel classification algorithm for the floating and sunken pulses.To study the validity of the suggested algorithm, we study clinically the correlation between algorithmic outcomes and the OMDs ‘diagnoses. The floating and sunken pulses belong to four principal pulses together with the rapid and slow pulses [1]. Therefore, one can not emphasize enough the importance of developing a reliable classification algorithm for the floating and sunken pulses. 90005 90006 2. Quantification of the Floating and Sunken Pulses 90007 90006 2.1. Floating Pulse and Sunken Pulse 90007 90002 According to «Mai Jing», the floating pulse is a pulse potent when felt with no pressure applied but impotent when felt with pressure applied, and the sunken pulse is a pulse impotent when felt with no pressure applied but potent when felt with pressure applied, while the hidden pulse is a pulse imperceptible until the fingers touch the bone with extremely heavy pressure [3].Similar definitions can be found in other classics such as «Bin Hue Mai Xue» or «Yi Xue Ru Men». A brief hypothetical explanation for the characteristic features of the floating and sunken pulses is as follows. The floating pulse is characterized as a Yang pulse and it is mostly seen in wind evil, external guest, and exterior patterns. The sunken pulse, on the other hand, is characterized as a Yin pulse and it is largely seen in those who have pathologic Qi hidden internally or interior patterns [2].In general, superficial pulses are associated with acute diseases of exterior origin, while deep pulses are indicative of more severe and chronic illnesses related to the internal organs. For instance, the sunken pulse without other symptoms indicates a high potential for the impaired immune system. It is worth noting that the pulses of obese subjects are normally deeper than those of thin individuals [4]. 90005 90006 2.2. Coefficient of the Floating and Sunken Pulses 90007 90002 There have been suggestions on how to quantify the pulse qualities defined only by the level of depth using pulse signals obtained by pulse-taking devices.As expounded by Fei [6], the floating / sunken / hidden pulses are distinguishable from the shape of the 90003 P 90004 — 90003 H 90004 curve (the curve of the pulse strength (90003 H 90004) as a function of the hold-down pressure (90003 P 90004)) as shown in Figure 1. Indeed, there are some pulse qualities other than the floating or sunken pulses that appear either at the superficial level or deep level, and they can be categorized as floating-type pulses or sunken -type pulses [1]. For instance, the scallion stalk pulse is a pulse exhibiting a floating characteristic combined with large but soft features (empty in the middle but solid at the sides when pressure is applied) [3].In this aspect, strictl 90005.90000 Review of Traditional Chinese Medicine Pulse Diagnosis Quantification 90001 90002 Qualification of tcm pulse diagnosis means the elements that tcm pulse diagnosis should be included in order to have a complete and valid assessment on tcm pulse. Literatures show that there is much confusion about the assessment of pulse in tcm, mainly due to the ambiguous descriptions of pulse condition in Chinese medical texts [1]. 90003 90002 Pulse itself is objective, but pulse condition is subjective.It is the quality of pulse as felt by a tcm doctor, and thus represents the subjective judgment of that doctor. More than 30 pulse conditions have been documented in Chinese medical texts. Some of them, e.g. floating, rapid, string-like are single pulse condition which describes one element of a pulse condition. Others describe more than one element of a pulse condition which is called compound pulse condition. For example, replete is the composite of forceful, long, large and stiff [2]. 90003 90006 2.1. Description of pulse condition in ancient Chinese medical texts 90007 90002 Nei Jing [3] describes over 30 types, e.g. large, small, long, short, slippery, rough, sunken, slow, rapid, strong, tough, soft, moderate, hurried, vacuous, replete, scattered, intermittent, fine, and weak. Mai Jing [4] documents 24 types which are floating, sunken, hollow, large, small, skipping, tight, rapid, stirred, slippery, weak, string-like, faint, soft, dissipated, moderate, slow, bound, drumskin, replete, intermittent, vacuous, rough and hidden.The 28 pulse conditions most commonly used in clinical practice come from Bin Hu Mai Xue [5] and Zhen Jia Zhen Gyan [6]. They are floating, sunken, slow, rapid, surging, fine, vacuous, replete, long, short, slippery, rough, string-like, tight, soggy, moderate, faint, weak, dissipated, hollow, drumskin, firm, hidden, stirred, intermittent, bound, skipping, and racing. 90003 90002 Descriptions of pulse conditions in Chinese medical texts are mostly qualitative, and are often illustrated by similes and poems.For instance, the slippery is compared to «beads rolling» and the string-like is like pressing the string of a musical instrument [5]. A few of the descriptions, such as the rapid, the slow, the floating, and the sunken, are quantitative. The rapid and the slow describe the rate of a pulse, and can be quantified by the number of beats per breath. The floating and the sunken describe the depth of a pulse, and can be quantified by shu, the unit of weight used during the Warring States period (403-221BC) of ancient China, with floating corresponding to three shu and sunken nine shu [7 ].90003 90002 Using analogies and poems to describe pulse condition is subject to the interpretation of the tcm doctor. For example, the string-like may be described as like pressing the string of a musical instrument and the tight as like pressing a rope, but the feeling of a string or a rope depends on the sensitivity of one’s fingers. Qualifying words such as «a bit,» «average,» and «very» are used to describe the intensity of a pulse. For example, the difference between the fine and the faint is that the fine is a little bit stronger than the faint.»A little» is countable, but can not precisely determine how much of this «little» differentiates the fine from the faint. 90003 90002 Descriptions of pulse conditions also overlap [8,9]. Some pulse conditions describe a single dimension of pulse. The floating, for example, describes the depth of a pulse, whereas the rapid describes the rate of a pulse. Others describe two or more dimensions. The firm means string-like, long, replete, surging, and sunken, whereas the drumskin is string-like, large, rapid, and hollow.The number of dimensions that a pulse assessment should encompass is controversial. Floating or sunken and slow or rapid are the two pairs of dimensions suggested in Bin Hu Mai Xue [5]. Nan Jing [7] and Mai Jing [4], in contrast, proposed three dimensions: floating or sunken, slippery or rough, and long or short. Nei Jing [3] described three dimensions: slippery or rough, slow or rapid, and surging or fine, whereas [2] suggested floating or sunken, slow or rapid, and vacuous or replete. 90003 90002 It is suggested that there are two reasons for the obscurity of descriptions of pulse condition.First, tcm doctors are accustomed to assessing pulse by their own perception, rather than on a rational basis [10]. Second, there are no concise and precise standards to guide tcm doctors in the diagnosis of pulse condition. It is likely that these two reasons are the causes of the low inter-rater and intra-rater reliability of pulse diagnosis by tcm doctors found by Craddock (1997) and Krass (1990) (as cited in [11]). As evidence-based practice emphasizes consistency of outcome [12], the low reliability of pulse diagnosis by tcm doctors reported in the literature demonstrates the need to standardize pulse diagnosis in tcm.90003 90006 2.2. Eight elements: Milestone for standardizing tcm pulse diagnosis qualification 90007 90002 Zhou Xuehai’s (1856-1906) early attempt to standardize pulse condition is a milestone in the quantification of tcm pulse diagnosis. He proposed that each pulse condition should have four elements. «Wei Shu Xing Shi Zhe, Zheng Mai Zhi Ti Wang. Qiu Ming Mai Li Zhe, Xu Xian Jiang Wei Shu Xing Shi Jiang De Zhen Qie, Ge Zhong Mai Xiang Liao Ran, Bu Bi Ju Ni Mai Ming «(as cited in [13], p. 31).He explicitly stated that position, frequency, shape, and trend are the four main elements of pulse condition, and that each pulse condition description should contain these four elements. 90003 90002 Various scholars have elaborated on this idea [2,14-18], and have extended the original four elements to eight: depth, rate, regularity, width, length, smoothness, stiffness, and strength. Each pulse condition should contain these eight elements with different intensities [2,15,17,18]. 90003 90002 Rate is the number of beats per breath.The definition of regularity is similar to that in modern medicine, it describes rhythm of a pulse condition. Rate and regularity gives information on the nature of a disease, whether heat or cold [19]. Depth is defined as the vertical position of a pulse, and indicates the location of a disease, whether interior or exterior [19]. Width and length describe the shape of a pulse, where width is defined as the intensity of a pulsation and length is defined as the range in which the pulsation can be sensed across the cun, guan, and chi [2].Smoothness is defined as the slickness of a pulse, stiffness is defined as the sensation of arterial elasticity, and strength is defined as the change in forcefulness of a pulse in response to a change of applied pressure [19]. Width, length, smoothness, stiffness, and strength also describe the interaction of a pathogen and healthy qi in the body [2]. The eight elements thus provide a basis for qualifying pulse condition. 90003 90006 2.3. Recent works on qualifying tcm pulse diagnosis 90007 90002 King et al.(2002) [11] developed a measurement scale to standardize tcm pulse diagnosis. However, their scale does not reflect pulse condition adequately for several reasons. First, the six items included in the scale -depth, width, force, relative force, rhythm, and pulse occlusion -are not widely accepted as core items in tcm pulse diagnosis. Appropriate rating scales should include the six locations, as a complete tcm pulse diagnosis must include the eight elements at the six locations. Second, the definitions of the items are abstract.For example, force is defined as the overall intensity of a pulse and relative force is defined as a subtler version with overall force. Third, the scale is an ordinal scale that is anchored with descriptors to measure the items. For example, depth is measured at three levels: superficial, middle, and deep. However, an ordinal scale is not a sufficiently sensitive measure, as there are an insufficient number of available response categories to rate the items [20], and the words used to describe each ordinal level are not universal.Further, as the items have not been well quantified, using an ordinal scale would not reflect the actual sensation perceived by a tcm doctor. 90003 90002 To explore the uniqueness of each of the eight elements in tcm pulse diagnosis, Tang (2010) [21] used principal component analysis to explore the uniqueness of each of the eight elements in tcm pulse diagnosis. The result demonstrated that rate, regularity, width and smoothness represented four unique dimensions while it was not the case for depth, length, stiffness and strength.90003 90002 The author believes that an appropriate content and rating scale must be chosen to measure pulse condition which should be relevant and should adhere to the fundamental concepts of pulse diagnosis in tcm. Since only a handful of studies have been conducted to qualify pulse condition, a rating scale which can genuinely reflect the sensation of pulse perceived by a tcm doctor should be used to minimize the influence of subjective judgment on a rating scale at a preliminary stage of qualification .90003.90000 Just a moment … 90001 90002 Please enable Cookies and reload the page. 90003 90004 This process is automatic. Your browser will redirect to your requested content shortly. 90003 90006 Please allow up to 5 seconds … 90003 90008 + ((! + [] + (!! []) + !! [] + !! [] + !! [] + !! [] + !! [] + !! [] + !! [] + []) + (! + [] + (!! []) — []) + (! + [] — (!! [])) + (! + [] + (!! []) +! ! [] + !! []) + (+ !! []) + (! + [] + (!! []) + !! [] + !! [] + !! [] + !! [] + !! [] + !! [] + !! []) + (! + [] + (!! []) + !! [] + !! [] + !! [] + !! [] + !! [] + !! []) + (! + [] + (!! []) — []) + (! + [] + (!! []) + !! [])) / + ( (+ !! [] + []) + (! + [] + (!! []) + !! [] + !! []) + (! + [] + (!! []) + !! [] + !! []) + (! + [] + (!! []) + !! [] + !! [] + !! [] + !! []) + (! + [] + ( !! []) + !! []) + (! + [] + (!! []) + !! [] + !! [] + !! [] + !! [] + !! [] + !! [] + !! []) + (! + [] + (!! []) + !! [] + !! [] + !! [] + !! [] + !! [] +! ! []) + (! + [] + (!! []) + !! [] + !! [] + !! [] + !! [] + !! [] + !! [] + !! []) + (! + [] + (!! []) + !! [] + !! [] + !! [])) 90003 90008 + ((! + [] + (!! []) + !! [] + !! [] + !! [] + !! [] + !! [] + !! [] + []) + (+ !! []) + (! + [] + (! ! []) + !! [] + !! [] + !! [] + !! [] + !! []) + (! + [] + (!! []) + !! [] +! ! [] + !! []) + (! + [] — (!! [])) + (! + [] + (!! []) + !! [] + !! []) + (! + [] + (!! []) — []) + (! + [] + (!! []) + !! [] + !! []) + (! + [] + (!! [] ) + !! [])) / + ((+ !! [] + []) + (+ !! []) + (! + [] + (!! []) + !! [] + !! [] + !! [] + !! [] + !! [] + !! [] + !! []) + (! + [] + (!! []) + !! [] + !! [ ] + !! [] + !! []) + (! + [] + (!! []) + !! [] + !! [] + !! [] + !! [] + !! [] + !! [] + !! []) + (! + [] + (!! []) + !! [] + !! [] + !! [] + !! [] + !! [] + !! []) + (! + [] + (!! []) — []) + (+ !! []) + (! + [] + (!! []) + !! [] + !! [] + !! [] + !! [])) 90003 90008 + ((! + [] + (!! []) +! ! [] + !! [] + !! [] + !! [] + !! [] + !! [] + !! [] + []) + (! + [] + (!! []) + !! [] + !! []) + (+ !! []) + (! + [] —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—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human disease | Definition & Facts 90001 90002 Health versus disease 90003 90004 Before human disease can be discussed, the meanings of the terms health, physical fitness, illness, and disease must be considered. Health could be defined theoretically in terms of certain measured values; for example, a person having normal body temperature, pulse and breathing rates, blood pressure, height, weight, acuity of vision, sensitivity of hearing, and other normal measurable characteristics might be termed healthy.But what does normal mean, and how is it established? It is well known that if the temperatures are taken of a large number of active, presumably healthy, individuals the temperatures will all come close to 98.6 ° F (37 ° C). The great preponderance of these values ​​will fall between 98.4 ° F (36.9 ° C) and 98.8 ° F (37.1 ° C). Thus, health could in part be defined as having a temperature within this narrow range. Similarly, a normal range can be established for pulse, blood pressure, and height. In some healthy individuals, however, the body temperature may range below 98.4 ° F or above 98.8 ° F. These low and high temperatures fall outside the limits defined above as normal and are instances of biological variability. 90005 90004 Biological criteria of normality are based on statistical concepts. Body height may be used as an example. If the heights of every individual in a large sample were plotted on a graph, the many points would fall on a bell-shaped curve. At one end of the curve would be the very short people, and at the other extreme the few very tall people.The majority of the points of the sample population would fall on the dome of the bell-shaped curve. At the peak of the dome would be those individuals whose height approaches the average of all the heights. Scientists use curves in determining what they call normal criteria. By accepted statistical criteria, 95 percent of the population measured would be included in the normal range-that is, 47.5 percent above and 47.5 percent below the mean at the very centre of the bell. Looked at in another way, in any given normal biological distribution 5 percent will be considered outside the normal range.Thus the 7-foot (213-cm) basketball player would be considered abnormally tall, but that which is abnormal must be distinguished from that which represents disease. The basketball player might be abnormally tall but still have excellent health. Thus, in any statistical analysis of health, the possibility of biological variation must be recognized. 90005 90004 A better example than height of how problems can arise with biological variability is heart size. If the heart is subjected to a greater than normal burden over a long period, it can respond by growing larger (the process is known as hypertrophy).This occurs in certain forms of heart disease, especially in those involving long-standing high blood pressure or structural defects of the heart valves. A large heart, therefore, may be a sign of disease. On the other hand, it is not uncommon for athletes to have large hearts. Continuous strenuous exercise requires a greater output of blood to the tissues, and the heart adapts to this demand by becoming larger. In some cases the decision as to whether an abnormally large heart represents evidence of disease or is simply a biological variant may tax the diagnostic abilities of the physician.90005 Get exclusive access to content from our тисяча сімсот шістьдесят вісім First Edition with your subscription. Subscribe today 90004 The effects of age introduce yet another difficulty in the attempt to define health in theoretical measured norms. It is well known that muscular strength diminishes in the advanced years of life, the bones become more delicate and more easily fractured, vision and hearing become less sharp, and a variety of other retrogressive changes occur. There is some basis for considering this general deterioration as a disease, but, in view of the fact that it affects virtually everyone, it can be accepted as normal.Theoretical criteria for health, then, would have to be set for virtually every year of life. Thus, one would have to say that it is normal for a man of 80 to be breathless after climbing two flights of stairs, while such breathlessness would be distinctly abnormal in an agile child of 10 years of age. Moreover, an individual’s general level of physical activity significantly alters his ability to respond to the ordinary demands of daily life. The amount of muscular strength possessed by an 80-year-old man who has remained physically active would be considerably more than that of his fragile friend who has led a confined life because of his dislike of activity.There are, therefore, many difficulties in establishing criteria for health in terms of absolute values. 90005 90004 Health might be defined better as the ability to function effectively in complete harmony with one’s environment. Implied in such a definition is the capability of meeting-physically, emotionally, and mentally-the ordinary stresses of life. In this definition health is interpreted in terms of the individual’s environment. Health to the construction worker would have a dimension different from health to the bookkeeper.The healthy construction worker expects to be able to do manual labour all day, while the bookkeeper, although perfectly capable of performing sedentary work, would be totally incapable of such heavy labour and indeed might collapse from the physical strain; yet both individuals might be termed completely healthy in terms of their own way of life. 90005 90004 The term physical fitness, although frequently used, is also exceedingly difficult to define. In general it refers to the state of optimal maintenance of muscular strength, proper function of the internal organs, and youthful vigour.The champion athlete prepared to cope not only with the commonplace stresses of life but also with the unusual illustrates the concept of physical fitness. To be in good physical condition is to have the ability to swim a mile to save one’s life or to slog home through snowdrifts when a car breaks down in a storm. Some experts in fitness insist that the state of health requires that the individual be in prime physical condition. They prefer to divide the spectrum of health and disease into (1) health, (2) absence of disease, and (3) disease.In their view, those who are not in prime condition and are not physically fit can not be considered as healthy merely because they have no disease. 90005 90004 Health involves more than physical fitness, since it also implies mental and emotional well-being. Should the angry, frustrated, emotionally unstable person in excellent physical condition be called healthy? Certainly this individual could not be characterized as effectively functioning in complete harmony with the environment. Indeed, such an individual is incapable of good judgment and rational response.Health, then, is not merely the absence of illness or disease but involves the ability to function in harmony with one’s environment and to meet the usual and sometimes unusual demands of daily life. 90005 90004 The definitions of illness and disease are equally difficult problems. Despite the fact that these terms are often used interchangeably, illness is not to be equated with disease. A person may have a disease for many years without even being aware of its presence. Although diseased, this person is not ill.Similarly, a person with diabetes who has received adequate insulin treatment is not ill. An individual who has cancer is often totally unaware of having the disorder and is not ill until after many years of growth of the tumour, during which time it has caused no symptoms. The term illness implies discomfort or inability to function optimally. Hence it is a subjective state of lack of well-being produced by disease. Regrettably, many diseases escape detection and possible cure because they remain symptomless for long years before they produce discomfort or impair function.90005 90004 Disease, which can be defined at the simplest level as any deviation from normal form and function, may either be associated with illness or be latent. In the latter circumstance, the disease will either become apparent at some later time or will render the individual more susceptible to illness. The person who fractures an ankle has an injury-a disease-producing immediate illness. Both form and function have been impaired. The illness occurred at the instant of the development of the injury or disease.The child who is infected with measles, on the other hand, does not become ill until approximately 10 days after exposure (the incubation period). During this incubation period the child is not ill but has a viral infectious disease that is incubating and will soon produce discomfort and illness. Some diseases render a person more susceptible to illness only when the person is under stress. Some diseases may consist of only extremely subtle defects in cells that render the cells more susceptible to injury in certain situations.The blood disease known as sickle cell anemia, for example, results from a hereditary abnormality in the production of the red oxygen-carrying pigment (hemoglobin) of the red cells of the blood. The child of a mother and father who both have sickle cell anemia will probably inherit an overt form of sickle cell anemia and will have the same disease as the parents. If only one parent has sickle cell anemia, however, the child may inherit only a tendency to sickle cell anemia. This tendency is referred to by physicians as the sickle cell trait.Individuals having such a trait are not anemic but have a greater likelihood of developing such a disease. When they climb a mountain and are exposed to lower levels of oxygen in the air, red blood cells are destroyed and anemia develops. This can serve as an example of a disease or a disease trait that renders the affected person more susceptible to illness. 90005 90004 Disease, defined as any deviation from normal form and function, may be trivial if the deviation is minimal. A minor skin infection might be considered trivial, for example.On the eyelid, however, such an infection could produce considerable discomfort or illness. Any departure from the state of health, then, is a disease, whether health be measured in the theoretical terms of normal measured values ​​or in the more pragmatic terms of ability to function effectively in harmony with one’s environment. 90005.