How should renal hemodynamic data be indexed in obesity?

Clearance data are customarily indexed to body surface area of 1.73 m2. This study examined whether this standard procedure gives correct values for renal perfusion in obese subjects. In 215 subjects who varied in age, gender, height, weight, obesity, and mean arterial blood pressure, RPF was determined by measuring the clearance of (131I)para-aminohippuric acid. Multiple regression analysis of the whole study group revealed that age (beta = -0.44, P < 0.001), height (beta = +0.25, P < 0.01), and arterial blood pressure (beta = -0.19, P < 0.01) were independent predictors of RPF, but that weight or body mass index was not. When related to body surface area, RPF appeared to decline with increasing obesity as follows: normal weight, 609 +/- 153 mL/min per 1.73 m2; overweight, 572 +/- 149 mL/min per 1.73 m2; severely overweight, 530 +/- 145 mL/min per 1.73 m2 (P < 0.012). In contrast, RPF related to height reflected a pattern concordant with the multiple regression analysis: normal weight, 3.76 +/- 0.9 mL/min per meter; overweight, 3.86 +/- 1.0 mL/min per meter; and severely overweight, 3.86 +/- 1.0 mL/min per meter (not significant). A separate repetition of the whole analysis for both normotensive (N = 55) and hypertensive subjects (N = 160) revealed a result similar to that found for the whole group. Thus, our results show that obesity was not a determinant of RPF, and when related to body surface area, inappropriately low values of RPF were calculated for obese patients. It was concluded that RPF values correlate with height and not with surface area in obese subjects.

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Oxygen Fraction Adjustment According to Body Surface Area during Extracorporeal Circulation

The Heart Surgery Forum ◽

10.1532/hsf.1325 ◽

2015 ◽

Vol 18 (3) ◽

pp. 098

Author(s):

Cem Arıtürk ◽

Serpil Ustalar Özgen ◽

Behiç Danışan ◽

Hasan Karabulut ◽

Fevzi Toraman

Keyword(s):

Body Temperature ◽

Surface Area ◽

Body Surface Area ◽

Body Surface ◽

Extracorporeal Circulation ◽

Group Iii ◽

Oxygen Fraction ◽

Arterial Blood ◽

Group I ◽

Group Ii

Background: The inspiratory oxygen fraction (FiO2) is usually set between 60% and 100% during conventional extracorporeal circulation (ECC). However, this strategy causes partial oxygen pressure (PaO2) to reach hyperoxemic levels (>180 mmHg). During anesthetic management of cardiothoracic surgery it is important to keep PaO2 levels between 80-180 mmHg. The aim of this study was to assess whether adjusting FiO2 levels in accordance with body temperature and body surface area (BSA) during ECC is an effective method for maintaining normoxemic PaO2 during cardiac surgery.Methods: After approval from the Ethics Committee of the University of Acıbadem, informed consent was given from 60 patients. FiO2 adjustment strategies applied to the patients in the groups were as follows: FiO2 levels were set as 0.21 × BSA during hypothermia and 0.21 × BSA + 10 during rewarming in Group I; 0.18 × BSA during hypothermia and 0.18 × BSA + 15 during rewarming in Group II; and 0.18 × BSA during hypothermia and variable with body temperature during rewarming in Group III. Arterial blood gas values and hemodynamic parameters were recorded before ECC (T1); at the 10th minute of cross clamp (T2); when the esophageal temperature (OT) reached 34°C (T3); when OT reached 36°C (T4); and just before the cessation of ECC (T5).Results: Mean PaO2 was significantly higher in Group I than in Group II at T2 and T3 (P = .0001 and P = .0001, respectively); in Group I than in Group III at T1 (P = .02); and in Group II than in Group III at T2, T3, and T4 (P = .0001 for all). Conclusion: Adjustment of FiO2 according to BSA rather than keeping it at a constant level is more appropriate for keeping PaO2 between safe level limits. However, since oxygen consumption of cells vary with body temperature, it would be appropriate to set FiO2 levels in concordance with the body temperature in the rewarming period.

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Doppler Transmitral Flow Velocity Parameters: Relationship between Age, Body Surface Area, Blood Pressure and Gender in Normal Subjects

American Journal of Noninvasive Cardiology ◽

10.1159/000470723 ◽

1987 ◽

Vol 1 (1) ◽

pp. 3-10 ◽

Cited By ~ 100

Author(s):

Julius M. Gardin ◽

Mary K. Rohan ◽

Dennis M. Davidson ◽

Ali Dabestani ◽

Mark Sklansky ◽

...

Keyword(s):

Blood Pressure ◽

Flow Velocity ◽

Surface Area ◽

Body Surface Area ◽

Body Surface ◽

Normal Subjects ◽

Transmitral Flow ◽

And Gender

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THE EFFECT OF MODEST WEIGHT LOSS ON ARTERIAL BLOOD PRESSURE AND METABOLIC PARAMETERS IN OBESE SUBJECTS

Journal of Hypertension ◽

10.1097/00004872-200406002-01293 ◽

2004 ◽

Vol 22 (Suppl. 2) ◽

pp. S369

Author(s):

E. K. Shavarova ◽

E. A. Nikitina ◽

A. O. Conrady

Keyword(s):

Blood Pressure ◽

Weight Loss ◽

Arterial Blood Pressure ◽

Metabolic Parameters ◽

Arterial Blood ◽

Modest Weight Loss ◽

Obese Subjects

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The Relation of Blood Pressure to Weight, Height and Body Surface Area in Schoolboys Aged 11 to 15 Years

Archives of Disease in Childhood ◽

10.1136/adc.27.131.43 ◽

1952 ◽

Vol 27 (131) ◽

pp. 43-53 ◽

Cited By ~ 23

Author(s):

L. Hahn

Keyword(s):

Blood Pressure ◽

Surface Area ◽

Body Surface Area ◽

Body Surface

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Height, Whole Body Surface Area, Gender, Working Outdoors, and Sunbathing in Previous Summer are Important Determinants of Serum 25-hydroxyvitamin D Levels

Experimental and Clinical Endocrinology & Diabetes ◽

10.1055/s-0031-1285912 ◽

2011 ◽

Vol 120 (01) ◽

pp. 14-22 ◽

Cited By ~ 19

Author(s):

K. Pazaitou-Panayiotou ◽

P. Papapetrou ◽

A. Chrisoulidou ◽

S. Konstantinidou ◽

E. Doumala ◽

...

Keyword(s):

Surface Area ◽

Body Surface Area ◽

Body Surface ◽

Skin Color ◽

Whole Body ◽

Hydroxyvitamin D ◽

25 Hydroxyvitamin D ◽

Obese Subjects ◽

Previous Summer ◽

Apparently Healthy

AbstractTo investigate if serum 25-hydroxyvitamin D (25(OH)D) is related to the whole Body Surface Area (BSA), and to several other anthropometric and environmental factors.Serum 25(OH)D was determined in 489 apparently healthy subjects (346 women and 143 men, mean age 43.9 years) in April and May. From all subjects the following data were available: height, body weight, waist to hip ratio, BSA, BMI, environment of work (indoors vs. outdoors), habit of regularly sunbathing during previous summer(s), fear of sun, dwelling in city or village, and skin color.Approximately 43% of the participants had serum 25(OH)D levels between 10 and 20 ng/ml, 44% had values between 20.1 and 30 ng/ml, whereas about 5% had values below 10 ng/ml and only 9% had values above 30 ng/ml. There was a significant positive relationship between 25(OH)D, height and BSA, which was more pronounced for BSA in obese subjects even after adjustment for work outdoors and sunbathing during previous summer(s). Outdoor workers and sunbathers had higher 25(OH)D compared to indoor workers and non-sunbathers respectively. Men when compared to women had higher 25(OH)D regardless of BMI and this difference was apparently due to the fact that men were taller, had greater BSA, and worked more often outdoors.Height, whole BSA, gender, working outdoors and sunbathing in previous summer(s) proved to be significant determinants of serum 25(OH)D. Vitamin D status is higher in taller individuals with greater BSA, and in men when compared to women.

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Procainamide Disposition in Obesity

Drug Intelligence & Clinical Pharmacy ◽

10.1177/106002808301700704 ◽

1983 ◽

Vol 17 (7-8) ◽

pp. 516-522 ◽

Cited By ~ 26

Author(s):

Patricia B. Christoff ◽

David R. Conti ◽

Cartha Naylor ◽

William J. Jusko

Keyword(s):

Body Weight ◽

Renal Clearance ◽

Surface Area ◽

Body Surface Area ◽

Body Surface ◽

Ideal Body Weight ◽

Tubular Secretion ◽

Pharmacokinetic Parameters ◽

Normal Mean ◽

Obese Subjects

The pharmacokinetics of intravenous procainamide (PA) were studied in seven obese and seven normal subjects. Serum concentrations and urinary excretion rates of PA and its active metabolite, NAPA, were measured by high performance liquid chromatography. Pharmacokinetic parameters were related to ideal body weight (IBW) and total body weight (TBW). The volume of distribution at steady state (Vssd) was similar for both groups when based per unit of IBW. Plasma clearance of PA, corrected for body surface area, was greater in obese subjects when adjusted for IBW, but similar on the basis of TBW. For its components, metabolic and renal clearance, the obese subjects showed similar metabolic clearances, but a significant increase was found in renal clearance per unit of body surface area based on both IBW (normal mean, 11.9 L/h/m2; obese, 19.0 L/h/m2) and TBW (normal mean, 11.7 L/h/m2; obese, 15.7 L/h/m2). This appears to be due to increased tubular secretion of PA in the obese group. In contrast, these subjects had lower renal clearances of NAPA. Variability in disposition of PA may, thus, be affected by patient physiology and method of parameter normalization.

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Left Ventricular Hypertrophy in Adolescents with Elevated Blood Pressure: Assessment by Chest Roentgenography, Electrocardiography, and Echocardiography

PEDIATRICS ◽

10.1542/peds.67.2.255 ◽

1981 ◽

Vol 67 (2) ◽

pp. 255-259

Author(s):

W. Pennock Laird ◽

David E. Fixler

Keyword(s):

Blood Pressure ◽

Left Ventricular Hypertrophy ◽

Surface Area ◽

Body Surface Area ◽

Body Surface ◽

Ventricular Hypertrophy ◽

Left Ventricular ◽

Elevated Blood ◽

Control Subjects ◽

Normotensive Control

The purpose of this study was to assess the prevalence of left ventricular hypertrophy in adolescents with persistently elevated blood pressures. Chest roentgenograms, electrocardiograms, and echocardiograms were performed on 50 adolescents with elevated blood pressure and 50 matched normotensive control subjects. No subject in either group demonstrated cardiomegaly on x-ray. Interpretation of the electrocardiograms indicated that similar numbers of both hypertensive (7/50) and control subjects (8/50) had ECG evidence of left ventricular hypertrophy. The echocardiograms showed that the mean left ventricular wall thickness (LVWT) in the hypertensive adolescents was 7.8 mm ± 0.1 (SE), compared with 6.5 ± 0.1 in the control subjects (P < .001). When the measurements were indexed to body surface area, the difference remained highly significant. Indexed left ventricular mass (LVM)/body surface area (BSA) was also significantly greater (P < .001) in the hypertensive (84.2 gm/sq m ± 2.1) than in the control subjects (72.0 ± 2.1). Using data from the normotensive control subjects, we defined the 95th percentile for both LVWT/BSA and LVM/BSA. Among hypertensive adolescents, 9/50 had LVWT/BSA and 8/50 had LVM/BSA above this level. For control subjects, only 1/50 had elevated LVWT/BSA values and 2/50 elevated LVM/BSA values. This study demonstrates that hypertensive adolescents have an increased prevalence of left ventricular hypertrophy and that echocardiography is the most useful noninvasive method to detect these changes.

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