The Advantages of Surface Area of the Body as a Basis for Calculating Pediatric Dosages

PEDIATRICS ◽  
1959 ◽  
Vol 24 (3) ◽  
pp. 495-498
Author(s):  
NATHAN B. TALBOT ◽  
ROBERT H. RICHIE
Keyword(s):  
Body Weight ◽  
Surface Area ◽  
Body Fluid ◽  
The Body

The use of surface area of the body as a basis for calculating fluid dosages has been questioned in recent communications. This letter is being written to call attention to certain facts which the authors of these communications appear to have overlooked. One is that body fluid requirements, like many other body functions, are not directly proportional to body weight. For this reason, Oliver et al. find it necessary to use five separate ml/lb-factors to calculate the fluid allowances of infants, children and adults. As can be seen in the table at the bottom of Figure 1, these diminish as individuals grow larger. Darrow likewise lists a series of eight factors to calculate body fluid requirements. Specifically he recommends that calories expended per kilogram be assumed to vary between 45 and 50 in the newborn, 60 and 80 in infants of 3 to 10 kg, 45 and 60 in children of 10 to 15 kg and so on down to a range of 25 to 30 in individuals weighing more than 60 kg.

scholarly journals The size of the trachea in warm-blooded animals, and its relationship to the weight, the surface area, the blood volume, and the size of the aorta

1912 ◽  
Vol 86 (584) ◽  
pp. 56-65 ◽  
Keyword(s):  
Body Weight ◽  
Surface Area ◽  
Cross Section ◽  
Body Surface ◽  
Body Fluid ◽  
The Body ◽  
Total Oxygen ◽  
Oxygen Capacity ◽  
Aortic Area ◽  
Main Factor

The analysis of data collected in connection with the investigation of a number of problems in immunity has led to a series of results, in part already published, bearing upon the blood and circulation. The conclusion was reached that in certain cases a precise and definite relationship to the body surface exists in warm-blooded animals in accordance with the formula W n / a = k , where W is the body weight of the animal, a represents the mass of the body fluid, tissue, or organ under investigation, k is a constant, and the value of n is approximately 0·70-0·72. In view of the fact that the carriage of oxygen is one of the chief functions of the circulation, and that the volume of the blood (1), (2), and the aortic area (3), (4), (area of cross-section of aorta), have been shown by us to be proportional to the body surface in warm-blooded animals, while, as we have also found, the total oxygen capacity is the main factor in determining the size of the heart (5), it appeared to be of interest to examine the size of the channel by which the oxygen gains access to the lungs.

scholarly journals STUDIES ON THE SUPRARENAL CORTEX

1933 ◽  
Vol 58 (1) ◽  
pp. 17-38 ◽  
Author(s):  
George A. Harrop ◽  
Louis J. Soffer ◽  
Read Ellsworth ◽  
John H. Trescher
Keyword(s):  
Body Weight ◽  
Blood Plasma ◽  
Body Fluid ◽  
Body Water ◽  
The Body ◽  
Regulatory Function ◽  
Original Form ◽  
Physiological Changes ◽  
Water Losses ◽  
Reverse Process

A characteristic alteration in the electrolyte structure of the blood plasma of the suprarenalectomized dog occurs when injections of cortical extract are stopped. This alteration progresses during the course of the suprarenal insufficiency, parallel with the hemoconcentration and the loss in weight. When injections of cortical extract are resumed, the electrolyte structure returns to its original form, the alterations paralleling the dilution of the blood and the return of the body weight to its original level. The hemoconcentration, with the resulting physiological changes which take place in the suprarenalectomized dog after the cessation of cortical extract injections, is associated with a loss of sodium and chloride, accompanied by their proper complement of body water, by way of the kidney. Since this effect is produced in the suprarenalectomized animal, well nourished and in excellent condition, solely by cessation of injections of the cortical hormone, and since the reverse process of repair of the electrolyte and water losses can be effected solely by resumption of extract injections, it follows that all of the observed phenomena are due to this cause, and to this alone. It can be concluded that one function of the cortical extract in the suprarenalectomized dog is that of participation in the regulation of the sodium and chloride metabolism, and consequently, of the balance and distribution of water. The loss of water, in the absence of the cortical hormone, is sustained partly by the blood plasma, but to a far greater extent by the interstitial body fluid. The available evidence points to the kidney as the locus of this regulatory function of the cortical hormone.

scholarly journals Establishing Standards for Studying Renal Function in Mice through Measurements of Body Size-Adjusted Creatinine and Urea Levels

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Wellington Francisco Rodrigues ◽  
Camila Botelho Miguel ◽  
Marcelo Henrique Napimoga ◽  
Carlo Jose Freire Oliveira ◽  
Javier Emilio Lazo-Chica
Keyword(s):  
Renal Function ◽  
Body Weight ◽  
Surface Area ◽  
Body Surface Area ◽  
Body Surface ◽  
Measurement Techniques ◽  
The Body ◽  
Urea Concentration ◽  
Time Points ◽  
Average Factor

Strategies for obtaining reliable results are increasingly implemented in order to reduce errors in the analysis of human and veterinary samples; however, further data are required for murine samples. Here, we determined an average factor from the murine body surface area for the calculation of biochemical renal parameters, assessed the effects of storage and freeze-thawing of C57BL/6 mouse samples on plasmatic and urinary urea, and evaluated the effects of using two different urea-measurement techniques. After obtaining 24 h urine samples, blood was collected, and body weight and length were established. The samples were evaluated after collection or stored at −20°C and −70°C. At different time points (0, 4, and 90 days), these samples were thawed, the creatinine and/or urea concentrations were analyzed, and samples were restored at these temperatures for further measurements. We show that creatinine clearance measurements should be adjusted according to the body surface area, which was calculated based on the weight and length of the animal. Repeated freeze-thawing cycles negatively affected the urea concentration; the urea concentration was more reproducible when using the modified Berthelot reaction rather than the ultraviolet method. Our findings will facilitate standardization and optimization of methodology as well as understanding of renal and other biochemical data obtained from mice.

Surface Area of the Body as a Basis for Calculating Dosages

PEDIATRICS ◽  
1960 ◽  
Vol 25 (1) ◽  
pp. 168-168
Author(s):  
DANIEL C. DARROW
Keyword(s):  
Body Weight ◽  
Surface Area ◽  
The Body ◽  
Variable Function

Nathan Talbot and associates (Pediatrics, 24:495, 1959) have done much to make doctors realize that interpretation of many physiological phenomena of patients of different sizes is simplified by relating them to a variable function of body weight rather than directly to body weight. Essentially the variable function of body weight is weight raised to the two-thirds power times a factor, and called "surface area." One cannot quarrel with this practice as long as it leads to better understanding of physiological principles.

Simplified Procedures for Calculating Drug Dosage from Body Weight in Infancy and Childhood

PEDIATRICS ◽  
1961 ◽  
Vol 27 (3) ◽  
pp. 503-506
Author(s):  
ANTHONY J. GLAZKO
Keyword(s):  
Body Weight ◽  
Surface Area ◽  
Body Surface Area ◽  
Body Surface ◽  
Drug Dosage ◽  
The Body ◽  
Infancy And Childhood ◽  
Adult Dose ◽  
Fixed Power ◽  
Simplified Procedures

The primary purpose of this communication is to describe some rather simple procedures for calculating pediatric doses when they are proportional to a fixed power of body weight. It is generally recognized that dose requirements per unit of body weight are usually higher for children than for adults. Consequently the total dose is not directly prportional to the body weight, but appears to be more nearly proportional to the body surface area. This requires preliminary estimation of the body surface area with the assistance of various charts and tables, following which the dose can be calculated by simple proportion when the adult dose is known.

scholarly journals VI. Further experiments upon the blood volume of mammals and its relation to the surface area of the body

1912 ◽  
Vol 202 (282-293) ◽  
pp. 191-212 ◽  
Keyword(s):  
Body Weight ◽  
Surface Area ◽  
Blood Volume ◽  
Body Surface ◽  
Guinea Pigs ◽  
The Body ◽  
Wild Animals ◽  
Wild Rats ◽  
The Individual

In previous papers* we have shown that the blood volume of normal and healthy mammals, such as rabbits, guinea-pigs, and mice, is satisfactorily expressed by the formula B = W n / k , where B is the blood volume in cubic centimetres, W the weight of the individual in grammes, n approximately ⅔, and k a constant (calculated from the experiments), which varies with the particular species of animal. This formula indicates that the smaller and lighter animals of any given species, which have a relatively greater body surface than the heavier ones, have also a relatively greater blood volume—in other words, the blood volume can be expressed as a function of the body surface , and it must therefore be misleading to express it in per cent, of the body weight, since when so expressed it is not a constant for any given species of mammal. As it was of interest to ascertain whether wild animals of closely allied species would differ greatly as regards their blood volume from the above-mentioned tame animals, we have determined the blood volume of hares, wild rabbits, and wild rats.

scholarly journals BODY FLUID CHANGES DUE TO CONTINUED LOSS OF THE EXTERNAL SECRETION OF THE PANCREAS

1928 ◽  
Vol 48 (6) ◽  
pp. 859-869 ◽  
Author(s):  
James L. Gamble ◽  
Monroe A. McIver ◽  
Keyword(s):  
Body Weight ◽  
Blood Plasma ◽  
Pancreatic Juice ◽  
Plasma Volume ◽  
Body Fluid ◽  
Chloride Ion ◽  
The Body ◽  
Ion Concentration ◽  
Ionic Content ◽  
Physical Changes

From the data given above the following explanation of the effects of continued loss of the external secretion of the pancreas may be offered. The underlying event is a steadily increasing deficit of sodium and of chloride ion due to the large requirement for these electrolytes in the construction of pancreatic juice. In consequence there is continued loss of water, chiefly from the body fluids in which sodium and chloride ion are large factors of total ionic content, viz., interstitial fluids and the blood plasma. During about two-thirds of the survival period the volume and composition of the blood plasma remain approximately normal, the losses of water, sodium, and chloride ion being replaced at the expense of interstitial fluids. Reduction of the volume of these fluids is indicated by loss of body weight beginning directly after establishment of the pancreatic fistula. Ultimately reduction of plasma volume begins and, as it progresses, serious symptoms develop and death occurs unless water, sodium, and chloride ion are abundantly replaced. Owing to the relatively greater loss of sodium than of chloride ion in pancreatic juice, reduction of bicarbonate ion concentration in the plasma tends to occur. The death of the organism may be simply and reasonably explained as the result of progressive impairment of the function of the blood by the physical changes, dehydration and acidosis, produced in the plasma by the continued loss of sodium and of chloride ion in the pancreatic juice.

MO656CORRELATION BETWEEN CHANGES IN THE BODY FLUID VOLUME CALCULATED BY THE URIC ACID KINETIC MODEL AND CHANGES IN THE BODY WEIGHT*

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
Shigeru Nakai ◽  
Kiyoshi Ozawa ◽  
Kazuhiko Shibata ◽  
Takahiro Shinzato
Keyword(s):  
Body Weight ◽  
Uric Acid ◽  
Kinetic Model ◽  
Weight Change ◽  
Body Fluid ◽  
Fluid Volume ◽  
The Body ◽  
Body Weight Change ◽  
Before And After ◽  
Body Fluid Volume

Abstract Background and Aims Uric acid (UA) is a solute unable to cross the cell membranes in general tissues by any of simple diffusion, facilitated diffusion or active transport. These facts imply that UA distribution volume (UDiV) equals to the extracellular fluid volume (ECFV). We have developed a method for calculating UDiV from serum uric acid levels before and after hemodialysis based on a uric acid kinetic model (Shinzato T, Int J Artif Organs 2020). Urea is evenly distributed throughout the body fluids. Therefore, the total body fluid volume (TBFV) can be calculated by using the same method as the calculation of UDiV for the serum urea level. The remaining body fluid volume, which is TBFV minus UDiV, is considered to reflect the intracellular fluid volume (ICFV). In this study, we clarified the relationship between the amount of change over time in UDiV and ICFV calculated by the uric acid kinetic model and the amount of change over time in the actual body weight of hemodialysis patients. Method Subjects were 1,101 patients with chronic maintenance hemodialysis. UDiV and ICFV before and after dialysis were calculated for two time points, December 2019 and June 2020. Results The amount of change in UDiV per body during the dialysis session showed a very good correlation with the amount of body weight change during the same dialysis (UDiV change = 0.950 x body weight change - 0.158, R-square 0.90, p < 0.0001). The amount of change in ICFV during the 6 months from December 2019 to June 2020 showed a good correlation with the amount of change in post-dialysis body weight during the same period (ICFV change = 0.270 x post-dialysis body weight change + 0. 240, R-square 0.21, p <0.0001). Conclusion These results suggest that the body fluid volume calculated by the uric acid kinetic model has high accuracy.

BODY SURFACE AS A BASIS FOR DOSAGE

PEDIATRICS ◽  
1959 ◽  
Vol 23 (1) ◽  
pp. 3-5
Author(s):  
GILBERT B. FORBES
Keyword(s):  
Body Weight ◽  
Linear Function ◽  
Surface Area ◽  
Body Surface ◽  
Clinical Investigation ◽  
Therapeutic Agents ◽  
The Body ◽  
Unit Body Weight ◽  
Area Rule ◽  
Older Child

MODERN therapeutic technology, with its array of drugs, sera and infusates, has demanded that the pediatrician devise some means whereby these materials can be given in proper dosage to subjects of widely varying size. At the same time modern clinical investigation has indicated the extent to which the human young differ metabolically and physiologically from adults. The practitioner has seen for himself that the dosage of many therapeutic agents is far from a simple linear function of body weight. The result has been the formulation of a number of dosage schemes, the most recent of which is the surface-area rule. In this scheme, dosage is expressed as grams or milliliters of a given material per square meter surface area rather than per unit body weight. Body surface is calculated from weight and height according to the conventional DuBois nomogram, or from weight alone. The use of this rule automatically provides the infant with a larger per kilogram dose than the older child. This is because surface area increases less rapidly than weight as the body grows.

scholarly journals P1228IMPROVEMENT OF BODY WEIGHT MANAGEMENT, BETA2-MICROGLOBULIN LEVEL AND RESISTANCE TO ERYTHROPOIESIS-STIMULATING AGENTS BY HYBRID PERITONEAL DIALYSIS PLUS HEMODIALYSIS THERAPY

2020 ◽  
Vol 35 (Supplement_3) ◽  
Author(s):  
Kanako Fukasawa ◽  
Mizuya Fukasawa
Keyword(s):  
Body Weight ◽  
Peritoneal Dialysis ◽  
Questionnaire Survey ◽  
Treatment Modality ◽  
Body Fluid ◽  
Hemoglobin Level ◽  
The Body ◽  
Continuous Treatment ◽  
Hybrid Therapy ◽  
Erythropoiesis Stimulating Agents

Abstract Background and Aims Peritoneal dialysis (PD) has the advantages of not causing rapid changes in the body fluid levels or solute contents in the blood due to the continuous treatment on all days of the week, and of not needing the patients to visit the hospital 3 times a week or lie on a bed for 4 hours to receive treatment. PD alone can, however, not adequately remove all the uremic toxins and excess water, and the patients are likely to be resistant to erythropoiesis-stimulating agents (ESA). These drawbacks could be potentially improved if PD and hemodialysis (HD) were used together. The aims of the present study were to clarify the changes in the body weight, serum β2-microglobulin (β2MG) level, and resistance to ESA in PD patients switched from PD alone to PD-HD hybrid therapy (hybrid therapy). Methods The data of seven patients who were switched from PD alone to PD-HD hybrid therapy at our hospital were retrospectively analyzed to determine the changes in the body weight, serum β2MG level, dose of ESA (Darbepoetin Alfa) and the hemoglobin level before and at 3 months after the switch to hybrid therapy; in hybrid therapy, the patient received HD once a week and did not receive PD on that day. We also carried out a questionnaire survey to determine the changes in the feeling of well-being and quality of life of the patients after the switch to hybrid therapy. Results and Discussion The body weight decreased significantly from 67.4 ± 11.8 kg to 63.7 ± 8.7kg (p = 0.0345) after the switch from PD alone to PD-HD hybrid therapy, indicating that the control of the body fluids was much easier with hybrid therapy than with PD alone. The mean serum β2MG level in the patients decreased from 37.3 ± 11.6 μg/mL to 32.6 ± 5.9 μg/mL (p = 0.1607, not significant), ; in particular, in those patients in whom the serum β2MG levels were over 30 μg/mL, the level decreased significantly from 42.5 ± 8.7 μg / mL to 34.4 ± 6.1 μg / mL (p = 0.0337). The dose of ESA decreased significantly in all patients from 193 ± 74 μg/month to 69 ± 38 μg/month (p = 0.006), while the hemoglobin level remained unchanged (from 10.2 ± 1.7 g/dL to 11.2 ± 1.2 g/dL, p = 0.1406). In the questionnaire survey, almost all the patients expressed positive feelings about the switch of the treatment modality, such as “it became easier to go up the stairs,” “improved working efficiency,” and “comfortable feeling.” Since the peritoneum was allowed to rest once in a week, on the day of the HD, it could also preserve peritoneal functions. Therefore, hybrid therapy was also considered to be effective from the viewpoint of performing PD over the long term. Conclusion We can expect easier management of the body fluid, efficient β2MG removal, and improvement of ESA resistance by switching the dialysis treatment modality from PD alone to HD-PD hybrid therapy.

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