Theodore H. D. Jones University of San Francisco San Francisco, California 941 17
Providing Relevance in Chemistry for Nursing Students
One of the more challenging courses that a university professor may he called upon to teach is an introductory course in chemistry for nursing students. Most university-associated Schools of Nursing have a definite requirement in chemistry which may extend from a one-semester survey lecture and lahoratory course to the more extensive multi-course sequence taken hy premedical and other health science oriented students. In either case the professor is faced with a significant challenge in several respects. Firstly, many beginning nursing students are unaware of the full extent of the scientific basis of their future professional work and hence come to see chemistry, physics, and other basic science requirements as being of little relevance to them and as serving primarily to eliminate weaker students from the nursing program. This attitude may lead to considerable resentment of these required courses which in turn makes it less likely that the student will benefit from the course to the extent that should he possihle. Secondly, many Schools of Nursing, for reasons of efficiency, schedule all of their basic science requirements in the freshman year leaving all clinical experience for the sophomore and later years. The result of this is to increase the student's sense of unrelatedness of chemistry and nursing and to make i t more difficult for the student to maintain a sense of motivation. For the professor it becomes more difficult to show the application of chemistry to nursing in a significant and meaningful way. For these reasons, the involvement of nursing students with chemistry is sometimes, in spite of the instructor's efforts, not a satisfying experience, and too many nurses will readily declare at a later time that they learned little from their chemistry courses or forgot much of what they did learn before reaching the stage in their clinical lahoratory experience a t which chemistry would have been valuable. Some of these difficulties have been encountered in Chemistry 40, a one-semester four-unit course (three lectures and one lahoratory session weekly) which we offer as a survey of the basic principles of general, organic, and biological chemistry and which is taken hy nursing students in the first semester of their freshman year to serve as the chemistry requirement for the nursing program. In our efforts to present this course while overcoming some of the potential difficulties referred to we have offered this course with a variety of emphases and strategems designed to motivate the student and to show the relevance of the course content to nursing. This paper describes one method of presentation which has proven very successful in achieving these goals. The entire course is currently oriented around one of the sets of data most frequently consulted by a nurse in the clinical situation uiz. the patient's clinical lahoratory chart. This is a recording of a hattery of twelve clinical chemistry analyses performed rountinely on body fluids, usually blood serum or plasma, of patients as they enter a hospital and throughout their stay there. The chart shows the normal ranges of values to he expected for each of a numher of ions and compounds of importance in clinical diagnosis and therapy, as well as a tracing which represents the values obtained for the particular patient. These materials are: calcium ion, inorganic phosphorous, glucose, blood urea nitrogen, uric acid, cholesterol, total protein, albumin, total bilirubin, alkaline phosphatase, lactate dehydrogenase and serum glutamate-oxaloacetate transaminase. This series of body components is used as the central theme in Chemistry 40 with each of the components
being systematieally examined in turn. However, as each is examined it is used as a means of introducing some new chemical concepts which are thus shown to he necessary for a more complete and thorough understanding of these materials. In this way we have been able to examine the most basic principles of general, organic, and biological chemistry while continuously relating these broader ideas to information which the students can appreciate is of continuous value to a practicing nurse. At the first meeting of the course copies of patients' laboratory charts displaying hoth normal values and also abnormal values are distributed. These are obtained from neighboring teaching hospitals which are usually quite willing to permit preparation of photo copies to he made as long as any patient-identifying names and numhers are first removed. The use of actual recently dated laboratory charts complete with the notations, comments, and initials of the clinical lahoratory technician, nurse, or physician convey to the student the sense of a working document. The first class meeting is devoted to examining the chart to see how it is arranged, noting the names of the components being measured and the units used in the measurement, and to see how a nurse might use this information. A clinical professor in the School of Nursing is invited to attend this first meeting and is asked to respond spontaneously to the chart showing the abnormal values. Depending upon the actual chart used, the nursing professor is able to draw some fairly definite conclusions from the chart about the patient's condition, suggesting what type of illness is exhibited, what organ systems are involved, and what type of medical treatment would prohahly he indicated. Further questions on the various compounds measured help to demonstrate the nursing instructor's knowledge of the nature and significance of each of these different materials. The result is a vivid demonstration of the value of a sound understanding of the chemical nature and physiological significance of particular body constituents and reveals more clearly than any explicit statements the scientific basis of nursing practice. Subsequent class meetings focus upon different aspects of the patient's chart. Examination of the data shows that several different units of measurement are used and the ohvious need to understand these units leads to a consideration of the different systems of measurement used in medical and scientific work. The British and SI systems are studied in detail; the apothecaries' system still in use in drug measurement (grains, minims etc) is also presented and its relationships to the more commonly used systems are explored. Attention is then focused upon the calcium ion and inorganic phosphorus which are the first materials noted on the laboratory chart. Classroom demonstrations of the reaction of calcium with water show clearly the reactive nature of this metal and the question naturally arises why the calcium in the body does not show the same reactivity. Answering this question necessitates consideration of some basic chemical ideas uiz. the existence and composition of atoms, the nature of elements, electron configurations and their corresponding reactivity or stability, and finally how atomic interactions can result in stability, thus leading to the formation of different types of chemical bond, molecules, and ions. All of these ideas are presented simply as part of the effort to understand the nature of the ions found in the body, whether they are simple ions like sodium, potassium, calcium, magnesium, and chloVolume 53, Number 9, September 1976 / 581
ride, or complex ions like ammonium, hicarbonate, sulfate, and the phosphates. The biochemical role of these ions is then discussed briefly and the clinical significance of variations in the concentration of these ions in hody fluids considered. This discussion is correlated with lahoratory experiments in which students analyze samples of hlood plasma and urine qualitatively and quantitatively for the presence of representative ions. Since measurements of these ions are recorded on the patient's lahoratory chart as concentrations, the need to understand the terms used in referring to concentrations hecomes obvious. At this point, the use of parts per million, milligram percent and gram percent solutions, moles and molarity is introduced. Dealing with these terms inevitably hrings the student to the point of having many questions about the phenomenon of solubility and the process of dissolution. In dealing with these questions, the nature of gases, liquids, and solids is introduced and a number of hody constituents are used as examples to show how the ohserved physical state and the solubility of substances are determined by their molecular size and the types of chemical bond they contain. The properties of solutions and colloids are studied with particular attention being paid to those phenomena with hiological significance, diffusion, dialysis, and osmosis. Having considered the nature of ions and the procedures used in describing concentrations of ions and compounds, the most important ion of all in hody chemistry, the hydrogen ion, is now introduced. The concept of p H and its importance in hody chemistry are descrihed and from this the study of those compounds, acids, bases, and buffer systems, which affect hydrogen ion concentration in the hody develops naturally. The next materials listed on a patient's lahoratory chart are glucose, blood urea nitrogen, uric acid, cholesterol, and total hiliruhin. The structure of each of these is presented and some comments made about their hiological significance. It becomes immediately obvious to the student that understanding the structure, nature, and behavior of such materials which are so different from the inorganic compounds examined up to this point requires some knowledge of organic chemistry, and the class undertakes the study of hydrocarbons and the derived classes of organic compounds in this light. This study is carefully integrated with a survey of carbohydrates, lipids, amino acids, and other low-molecular weight cellular components so that the ideas heing encountered are continually heing illustrated by direct reference to corresponding examples on the lahoratory chart uiz. glucose, cholesterol, urea, and bilirubin. Thus, by focusing the students' attention upon these few compounds of undisputed clinical importance, the professor is able to demonstrate the relevance of organic and low molecular weight biochemical compounds to patient care without the presentation degenerating into a dull and pedantic study of seemingly irrelevant chemical compounds. The study of the aminoacids, in relation to their role as the source of blood urea nitrogen, leads directly into the study of proteins. The clinical measurement of total protein and of albumin point up the need for an understanding of the chemical nature, properties, and hiological functions of proteins. The measurement of alkaline phosphatase, lactate dehydrogenase, and serum glutamate-oxaloacetate transaminase leads to questions about the special properties and functioning of enzymes in hiological processes, and this study is then expanded into a more complete survey of the major metabolic pathways in the hody. The study of glycolysis and the oxida-
582 / Journal of Chemical Education
tive metabolism of carbohydrates and lipids results in a more complete understanding of the value of lactate dehydrogenase in the blood stream as an indicator of heart muscle damage resultineu from mvocardial infarction. and of the value of ahnormal glucose concentrations in the hlood stream as an indicator of diabetes mellitus or other conditions which result in disturbance of the normal metaholism of carbohydrates. The eeneral oathwav for theconversion of theamino eroum " " . of amino acids into the nitrogen portion of urea can he examined in detail a t this stage, thus completing ideas touched upon earlier during the study of amino acids. Other topics of clinical significance which are related to the overall process of metabolism may also he introduced at this point; examples included the mode of action of sulfa drum and penicillin, current systematic efforts to develop new drigs hy the rational design of enzyme inhibitors, man's limited capacity to synthesize the common amino acids, nitrogen balance. and the nutritional consequences of these biochemical phenomena. The course concludes with a discussion of the medical consequences of over- or under-production of specific enzvmes. Examples studied include inherited hone diseases (ilecreased alcaline phosphatase concentrations), phenylke. tonuria. aalactosemia. and t h e 1.esch-Nvham rvndrome. The hioche&al mechanisms responsible for the synthesis of proteins and for reeulatine the structure and amount of particular proteins synthesired are described and are illustrated by reference to sickle-cell hem(,alohin and thalausemia. 'The involvement of nucleic acids in these processes is presented in as much detail as time permits. Consideration of these topics leads into discussion of some of the most recent accomplishments in the area of molecular hioloev -.in constructine hvbrid cells. detectine chromosomal abnormalities, cloning embryos, etc., and from these experiments ethical questions develop readily for class discussion. Thus, the ultimate consequences of the scientific ideas and technioues presented throuehout the course lead inevitahlv to choi'ces and decisions wLich must he confronted by the student both as an individual and as a ~rofessionalhealth worker. The course proeram descrihed above is comhined with appropriate lahoiato& experiments as well a s with visits to lo& teachine hosdtals in association with upper .. division nursing students to see some of the scientific aspects of nursing i; practice. In the topics presented the course may not differ significantly from other courses which also attempt to survey general, organic, and biological chemistry in one semester. What is novel is centering the course content around a chart which students readily recognize as heing an important diagnostic tool in their future daily care of the hospitalized patient. By relating every . maior . section of the course directlv to this ch& and h i using the course to explain and expand upon the nature of the materials listed in this chart the professor encourages in the student the feeling of heing involved in a study which will be of direct relevance to her daily work rather than of studying some irrelevant academic requirements which are only tangentially of value or significance. We have found that this approach satisfies the desire of the student for relevance while allowing the professor to offer the type of comprehensive conceotuallv oriented anaroach to chemistrv .. thatwe believe will oltimately have as significant an effect upon the student's understandine of the world as the narrower fact-oriented career-training approach often sought by students at this stage of their education.
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