OBJECTIVE: To determine reference values for fat-free mass index (FFMI) and fat mass index (FMI) in a large Caucasian group of apparently healthy subjects, as a function of age and gender and to develop percentile distribution for these two parameters. DESIGN: Cross-sectional study in which bioelectrical impedance analysis (50 kHz) was measured (using tetrapolar electrodes and cross-validated formulae by dual-energy X-ray absorptiometry in order to calculate FFMI (fat-free mass=height squared) and FMI (fat mass=height squared). SUBJECTS: A total of 5635 apparently healthy adults from a mixed non-randomly selected Caucasian population in Switzerland (2986 men and 2649 women), varying in age from 24 to 98 y. RESULTS: The median FFMI (18 -34 y) were 18.9 kg=m 2 in young males and 15.4 kg=m 2 in young females. No difference with age in males and a modest increase in females were observed. The median FMI was 4.0 kg=m 2 in males and 5.5 kg=m 2 in females. From young to elderly age categories, FMI progressively rose by an average of 55% in males and 62% in females, compared to an increase in body mass index (BMI) of 9 and 19% respectively. CONCLUSIONS: Reference intervals for FFMI and FMI could be of practical value for the clinical evaluation of a deficit in fat-free mass with or without excess fat mass (sarcopenic obesity) for a given age category, complementing the classical concept of body mass index (BMI) in a more qualitative manner. In contrast to BMI, similar reference ranges seems to be utilizable for FFMI with advancing age, in particular in men.

Severe respiratory insufficiency causes patients to be intolerant of physical effort and to be frequently limited in their daily activity and results in an imbalance between food intake and nutritional needs. Undernutrition and overnutrition can both affect the quality of life and survival of patients with pulmonary disease. Protein-energy malnutrition can lead to quantitative, qualitative and functional alterations of muscle [1,2] and this affects muscle function, including respiratory muscle in patients with already limited respiratory reserves. Optimal adaptation of nutrition support through the assessment of fat-free mass (FFM) and fat mass (FM) in patients with chronic respiratory insufficiency can avoid or minimize muscle wasting or obesity. For these reasons, the nutritional assessment should include body composition measurements which are based on objective rather than subjective criteria of nutritional evaluation. Body composition can be measured by a number of techniques, including hydrodensitometry, isotope dilution, and whole-body counting of potassium-40 [3]. However, these methods are not easily applicable in ill subjects.More recent methods for the determination of the FFM are dual-energy X-ray absorptiometry (DXA) and bioelectrical impedance analysis (BIA). DXA has been validated against independent methods, including a gamma neutronactivation model [4,5], total body potassium and hydrodensitometry [6] and is becoming one of the reference methods for body composition analysis, but requires sophisticated technology. BIA is a method of measuring body composition which is easy, noninvasive and inexpensive [7]. BIA measurements have been validated in healthy adults [8][9][10]. The relationship between body impedance and body composition is dependent on age and sex [11,12]. Over 20 different formulae permit the calculation of the FFM and FM based on BIA measurements and have generally been validated in healthy, young adults. SCHOLS et al. [13] proposed a BIA formula validated against deuterium dilution for patients with chronic obstructive pulmonary disease (COPD) (n=24), which included weight and height 2 /resistance (ht 2 /R) as independent variables. Recently, PICHARD et al. [14] were unable to obtain clinically relevant correlations between FFM calculated by 12 BIA formulae [8,9,11,[15][16][17][18][19][20][21], including SCHOLS et al. [13], and DXA-determined FFM, and suggested that a specific formula should be developed for patients with chronic severe respiratory insufficiency. These results suggest that the bioelectrical impedance analysis formula specific to patients with severe respiratory insufficiency give a better correlation and smaller mean differences than 12 different bioelectrical impedance analysis formulae described in the medical literature. A prediction equation, validated against dual-energy X-ray absorptiometry and based on subjects with similar clinical characteristics, is more applicable to the patients with respiratory insufficiency than a formula developed for healthy subje...

The aim of this study was to investigate the haemodynamic and endocrinological effects of noninvasive positive pressure ventilation (NIPPV).Eleven patients with oedema and recent hypercapnic and hypoxaemic worsening of a chronic respiratory insufficiency were included. Echocardiography, cardiac radionuclide assessment, blood catecholamines, salt and water handling hormones were measured at admission and discharge (long study (LS)). To discriminate between the action of NIPPV and other treatments, measurements were performed on the fourth day, for 4 h without NIPPV and 4 h with NIPPV (short study (SS)).NIPPV entailed a correction of Pa,CO 2 and an increase of Pa,O 2 in LS and SS. Oedema disappeared. Body weight decreased (from 85±42 to 81±40 kg) during LS. Systolic and mean pulmonary arterial pressure decreased in LS and SS. Right ventricular ejection fraction increased in LS. Left ventricular ejection fraction did not change. Cardiac index was normal on admission and then decreased. Natriuretic peptides and catecholamines were increased on admission, whereas plasma renin activity, aldosterone and vasopressin were normal.We suggest that in these patients, oedema can occur independently of reninangiotensin-aldosterone-vasopressin and with a normal cardiac output. Noninvasive positive pressure ventilation allowed a correction of blood gases, associated with the resolution of oedema, a decrease in pulmonary arterial pressures and an increase in right ventricular ejection fraction. Eur Respir J 1997; 10: 2553-2559 Severe chronic respiratory insufficiency often leads to pulmonary arterial hypertension and cor pulmonale, which are associated with increased mortality [1]. Peripheral oedema is often witnessed in these patients, and the traditional view has been to assume that this results from right ventricular failure and/or the increased secretion of salt and water-handling hormone [2,3]. Longterm noninvasive positive pressure ventilation (NIPPV) is effective in improving blood gases and thereby decreasing pulmonary hypertension, clearing oedema, and reducing morbidity and mortality associated with this condition [4]. Its beneficial effects on oedema could result from improved right ventricular function and cardiac output as well as a lowering of salt and water-handling hormone levels, as demonstrated during invasive mechanical ventilation [5]. However, there is a scarcity of published data on the consequences of NIPPV on pulmonary haemodynamics, ventricular function and hormonal patterns in oedematous patients with chronic respiratory insufficiency in which long-term ventilatory support is initiated.The aims of this study were, therefore: 1) to measure the haemodynamic effects of NIPPV, which would be expected to reduce pulmonary arterial pressure and improve right ventricular ejection fraction because of the correction of Pa,CO 2 and Pa,O 2 ; 2) to explore the haemodynamic and endocrine profiles of patients during a recent worsening of chronic hypercapnic respiratory insufficiency, in particular the major h...

In mechanically ventilated patients with acute lung injury, VO2pulm was increased and led to a 19% underestimation of VO2wb determined by the reverse Fick method, as well as to a 4.2% overestimation of calculated Qva/Qt. Lung inflammatory activity was increased, as assessed by BAL cellularity, IL-6 and elastase levels. However, there was no correlation between VO2pulm and the intensity of pulmonary inflammation.