(b) Basic Principles of Biomedicine (Western medicine)

Biomedicine is the “medicine based on the principles of the natural sciences (biology, biochemistry, biophysics, etc.)” (Dorland's Illustrated Medical Dictionary, 32nd ed., s.v. “biomedicine”). This tradition arose with the scientific revolution of the seventeenth to eighteenth centuries in Europe, and now has become the dominant medicine in the world. It relies on scientific method and modern technology, and demonstrates its efficacy in dealing with various diseases through its numerous specialties. It explains diseases with natural causes, and has a welldeveloped system of diagnosing and treating problems (Saethre 2008, 64; Wiley and Allen 2009, 7).

Modern biomedicine, according to Levinson and Gaccione (1997, 47-50), has three characteristics: the reliance on science and scientific principles, the usage of technology, and a high degree of specialisation. Regarding the reliance on science and scientific principles, biomedicine relies heavily on natural sciences especially biological sciences. It explores not only the gross organs and systems of the body and their functions (i.e. anatomy and physiology), but also the tissues, the cells, and the molecular components (such as DNA). Furthermore, based on Descartes’ ideology of mind-body dualism, the physical body is viewed as a machine and its material parts are examined and dealt with “objectively”. It rejects the metaphysical humoral theory of Hippocrates-Galen, let alone the supernatural idea of disease and magico-religious treatment. Scientific methods–by means of “careful and unbiased observation and experimentation” (Levinson and Gacchione 1997, 47)–are applied to study the human body, to investigate diseases and their causes, and to develop effective treatments. The results of scientific experiments are analysed systematically, critically and rationally, and have to be repeatable and verifiable. In this way, the virtues of scientific rationality, as Kleinman (1993, 20) states, “generalizability, quantification, prediction, efficiency, quality control–are now ingrained in the professional structure of biomedicine.” In addition, there is a strong interdependence between basic sciences and clinical medicine. While basic sciences provide new data for further clinical research or new substances for medical application, clinical medicine has new diseases or discoveries which become new topics for research in basic sciences (Kang 1997, 32).

With respect to the use of technology, modern medicine is strongly associated with technology in its scientific research and clinical practice. Low-tech instruments are frequently used in a clinical setting–for example, a stethoscope for listening to the heart and lungs; a laryngoscope to examine the larynx; an ophthalmoscope to look at the interior of an eye; etc. High-tech apparatuses–such as electron microscopy, computed tomographic scan, magnetic resonance imaging, and many others–are also widely employed in biomedical research and clinical medicine. New technology promotes further research and application in medical sciences and clinical practices. Discoveries and inventions in biomedical engineering and biotechnology,^[1] for instance, furnish new knowledge, instruments, and materials which potentiate novel methods and even fresh areas in biomedicine for further research; these then provide innovative applications in diagnosis or therapy. New technology (such as the use of the internet) also speeds the communications between scientists/physicians and contributes to rapid updates/ advances in modern medicine (Kang 1997, 16, 38, 77-80; Levinson and Gaccione 1997, 48).^[2]

As for specialisation, modern medicine includes many specialties and subspecialties, in both divisions of medical research and clinical practice. In these specialties or subspecialties, professionals usually focus on specific areas of interest, which can be certain parts/systems of the body, diseases, treatments, or areas of research. These specialists receive advanced training in universities or health institutions, with supervision from professional organisations (such as various colleges of specialists) (Kang 1997, 43-65; Levinson and Gaccione 1997, 49-50). Modern medicine can be chiefly categorised into medical sciences and clinical specialties. There are many disciplines in each of these two major categories, with many new ones still developing. Medical sciences include anatomy, physiology, biochemistry, histology, embryology, pathology, pharmacology, microbiology, immunology, epidemiology, and so on. Clinical specialties encompass internal medicine, surgery, paediatrics, obstetrics and gynaecology, anaesthetics, emergency medicine, family medicine, psychiatry, diagnostic radiology, rehabilitation medicine, and so forth. Subspecialties are numerous. For internal medicine, there are cardiology, respiratory medicine, neurology, nephrology, gastroenterology, haematology, endocrinology, clinical immunology, rheumatology, dermatology, geriatric, and so on; for surgery, there are neurosurgery, ophthalmology, otorhinolaryngology, cardiothoracic surgery, abdominal surgery, urology, orthopaedics, paediatric surgery, vascular surgery, and so forth.^[3] Apart from these, there are also paramedical health professionals (such as nurse, physiotherapist, occupational therapist, speech therapist, clinical psychologist, social worker, prosthetist, radiographer, etc.) and supporting professionals (such as health administrator, chaplaincy, ward assistant, etc.) in the modern healthcare system.

In biomedicine, disease is regarded as “a harmful deviation from the normal structural or functional state of an organism” (Encyclopӕdia Britannica Online, s.v. “disease”).^[4] It is due to natural or biological factors within the body (i.e. intrinsic, endogenous) or from the environment (i.e. extrinsic, exogenous). The endogenous factors chiefly refer to genes and DNA, while the exogenous factors come from the external environment acting on and injuring the body tissues (Vardaxis 2010, 13). Biomedical physicians therefore aim at finding out the specific natural or biological factors responsible for the disease, and treat them accordingly. These factors can be regarded as predisposing or aetiological: the former factors make people more prone to disease, and the latter are the chief causes of disease. Predisposing factors comprise heredity, age, gender, lifestyle, and environment. Causes of diseases are numerous, and they can be classified as hereditary (due to defective genes or abnormal chromosomes), congenital (due to agents acting on pregnant woman which leads to malformation of foetus), infective (due to microorganisms including bacteria, fungi, viruses, parasites, and protozoa), immunological (which can be allergic or hypersensitive states of the immune system against one’s own body tissues, or autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus, etc.), or immune deficiencies due to genetic or external agents such as irradiation or human immunodeficiency virus (HIV)), neoplastic (i.e. abnormal growth of tissues which can be benign or malignant), vascular (which can be arterial such as heart attack (ischaemic heart diseases) and stroke (cerebral vascular diseases), or venous such as venous thrombosis), nutritional (due to malnutrition or overnutrition), traumatic (caused by external physical or chemical agents, such as burns, toxins, etc.), psychogenic (due to the patient’s psychological or emotional state), iatrogenic (due to medical treatment or hospitalization), and idiopathic (due to unknown or hidden causes). Moreover, many disorders are multifactorial, i.e. they are caused by more than one factor, and physicians have to correct them in order to eliminate the disease.^[5]

In modern biomedicine, making a diagnosis of a patient’s disease is a crucial clinical judgement. It is a methodical and logical process based on data acquired from the patient, through systemic interview, careful observation and rational investigation. The purpose of diagnosis is not merely for labelling the disease, but it also helps indicating the prognosis and guiding the clinical management. Moreover, through monitoring the clinical abnormalities associated with the diagnosis, the effectiveness of treatment and the eradication of disease can be evaluated (Kottow 1992, 19-20). To make a clinical diagnosis, several routines are usually followed: taking medical history from the patient, performing a physical examination of the patient’s body, determining the possible diagnoses (i.e. the process of differential diagnosis), and conducting certain investigative tests. Taking the patient’s medical history involves asking the details of the patient’s complaints (i.e. the “symptoms”–the subjective phenomena of the disease), past and/or persisting health problem(s), familial or hereditary medical conditions, social history (relating to occupation, domestic situation, overseas travel, and social habits such as tobacco and alcohol consumption), past experience of drug allergy, current use of medications or therapies, and a system review (enquiry of organ systems in order to elicit any other symptoms of the patient). Physical examination aims at looking for objective evidence of disease (the “signs”). The process is systematic and covers the whole body, though it usually focuses on the body part of possible affliction which is suggested by the medical history. Four clinical skills are performed–inspection (visual examination of the body and parts), palpation (examination via the sense of touch), percussion (assessment of a body part by tapping the surface with the fingertips), and auscultation (listening for sounds within the body)–to elicit any abnormalities in the body. After the history-taking and physical examination, usually the physician will make a differential diagnosis, with listing the diseases which have the similar pattern of symptoms and signs. Then diagnostic tests such as laboratory and/or imaging studies will be ordered to help decide or confirm the diagnosis. There is a wide array of tests which can be performed. Common tests include blood analyses, urine analysis (urinalysis), electrocardiography (ECG), Xrays, microscopic examination of body fluid/tissue, and so on. These tests not only can decide or confirm the diagnosis, but often can screen for other existing abnormalities in the body. Other complex tests–such as advanced imaging (e.g. ultrasonography, CT scan, MRI, PET scan), endoscopic examination, body tissue biopsy and examination, microbial culture, and so forth–can be arranged if the diagnosis is not yet certain or other major abnormalities are found. Through the above process–taking the medical history, performing the physical examination, and conducting the investigative tests–the collected findings are summarised, analysed, and elucidated to come to the diagnosis, which then will decide the treatment and prognosis (Frazier and Drzymkowski 2013, 20-24).

After establishing the diagnosis of the patient’s illness, the next step is prescribing the treatment for the patient. The physician explains to the patient about his or her condition, and offers him or her appropriate treatment options as well as an explanation of expected outcome and prognosis. With the patient’s agreement, the physician then will implement the appropriate interventions. The purpose of the therapy can be curative, supportive (e.g. rest, hydration, symptomatic relief, etc. for influenza), palliative (i.e. relieving the symptom but not curing the disease, usually for terminal illnesses or chronic diseases), or a combination of these. The choice of treatment depends on the disease, the physician’s suggestion, and the patient’s choice. There are many different forms of therapy in modern medicine, and in general these include medications, surgical operations, and/or radiation therapy. The treatments are utilised for treating the cause(s) and/or relieving the symptoms. Other measures such as diet modification, exercise, physiotherapy, psychotherapy, social/ familial support, etc. may be included in the therapy and these are provided by other health professionals (such as nurse, dietitian, physiotherapist, clinical psychologist, social workers, etc.). Referral to another specialist clinician for special intervention may be arranged if the patient’s health problem deems necessary. The treatment can be carried out in a hospital, clinic, health centre, or at home; this depends on the patient’s problem and the complexity of treatment. The efficacy of the therapy is constantly evaluated when following up the patient, and the treatment can be altered if necessary (Frazier and Drzymkowski 2013, 21).^[6]

Apart from treating the patient’s disease, another significant aspect of modern medicine is to prevent disease and to maintain the health of individuals. There is a system of three levels of prevention, which virtually includes all the medical activities. Primary prevention aims at eliminating the risk factors or causes of disease and enhancing resistance to disease, so that disease will not develop. Examples of activities are vaccination, consumption of a healthy diet, regular exercise, and so on. Secondary prevention concerns early detection of disease or its precursory pathological change before symptoms appear. Measures of this level include routine physical check-up, regular breast examination, pap-smear, and so forth. Tertiary prevention attempts to stop or limit the progress of disease which has already appeared, so that its physical and social consequences can be reduced or minimised. Rehabilitative measures–e.g. physiotherapy, occupational therapy, and other therapies for stroke patients to limit the disability–belong to this level of prevention (Jekel et al. 2007, 227-229).

There are yet several special features of modern medicine worthy of mention. Firstly, modern medicine is speedily advancing. Numerous research studies are being done, with diverse discoveries and inventions adding to medical knowledge. In order to best apply such knowledge, evidence-based medicine is emphasised nowadays. Evidence-based medicine has been clearly defined by Sackett et al. (1996, 71-72) as “the conscientious, explicit, and judicious use of current best evidence in making decisions about the care of individual patients.” It is the practice of the best clinical care for the patient on the basis of the best available evidence gathered from current research, physicians’ expertise, and the needs and preferences of the patient (Dorland's Illustrated Medical Dictionary, 32nd ed., s.v. “medicine: evidence-based m.”). ^[7] Secondly, biological research probes deeper and deeper into cells and molecules. Since the latter half of the twentieth century, cell biology and molecular biology have played a more dominant role. Researchers have applied these new scientific methods and knowledge to other biomedical disciplines, resulting in many new areas of interest such as molecular physiology, molecular pathology, molecular neuroscience, molecular immunology, molecular endocrinology, molecular genetics, molecular microbiology, molecular pharmacology, and so on. This has had a significant impact on biomedical knowledge and on the clinical application of diagnosis, treatment and prevention (Kang 1997, 21-24, 38-39, 45). Thirdly, apart from those developing branches of medical sciences or specialties dealing with the microscopic/molecular level of body tissues and cells, modern medicine nowadays also has growing disciplines caring for the whole individual and his/her association with society and environment. These are special fields such as public health, rehabilitation medicine, social medicine, environmental medicine, and so forth. There are also interdisciplinary fields developed in the last few decades, dealing with humanistic and social issues, such as medical sociology, medical anthropology, medical humanities, medical ethics and many others (Kang 1997, 2-3, 24-27, 35-36, 39-40). Lastly, modern biomedicine has been strongly criticised for its mechanistic view of the physical body as well as its focus on disease but not health. Because of such a view and focus, the patient’s psychological, social and spiritual needs are not cared for, and health maintenance and promotion is not stressed. But nowadays modern medicine has paid more attention to these critiques, and a holistic approach to healthcare–taking care not only of the physical body but also of the psychological, emotional, social, spiritual and environmental aspects of an individual by different healthcare providers (such as psychologists, social workers, chaplains, and even practitioners of complementary and alternative medicine)–is becoming more emphasised and gaining popularity (Frazier and Drzymkowski 2013, 21, 24-25).

Footnotes and references:

[1]:

Biomedical engineering, also known as bioengineering, is “the use of engineering in biomedical technology such as the analysis of movement of body parts or prosthetics.” Biotechnology refers to “any application of technology that uses biological systems, organisms, or their derivatives, to create new products or processes or modify existing ones.” See Dorland's Illustrated Medical Dictionary, 32nd ed., s.v. “engineering: biomedical e.” and “biotechnology”.

[2]:

Although new technology brings a positive impact on biomedicine, over-reliance on technology also has negative effects, such as an inhumane hospital environment, reduced doctor-patient contact and communication, declined clinical skills and experience of the healthcare staff, and new health problems due to technological advances (e.g. those diseases relating to environmental pollution).

[3]:

There are too many medical sciences or specialties/subspecialties to be covered here. For detailed information on specialisation in different countries, see General Medical Council 2011. Moreover, nowadays there are many interdisciplinary fields, such as medical humanities and medical informatics.

[4]:

Encyclopædia Britannica Online, s.v. “disease” [accessed November 23, 2014, http://academic.eb.com/EBchecked/topic/165521/disease].

[5]:

This brief enumeration of the predisposing and aetiological factors of disease is gathered from Tamparo and Lewis 2011, 3-20, and Vardaxis 2010, 13-29.

[6]:

There are numerous forms of treatment. For a concise description of various treatments, see Encyclopædia Britannica Online, s.v. “therapeutics (medicine)” [accessed November 24, 2014, http://academic.eb.com/EBchecked/topic/591185/therapeutics].

[7]:

In the last decade, there is a new discipline which is closely related to evidence-based medicine, and it is known as “translational medicine”. This term has been defined differently by various people, but it generally refers to “the translation of basic research discoveries into clinical applications” (Cosmatos and Chow 2009, ix).