Application of subjective global assessment as a screening tool for malnutrition in surgical patients in Vietnam.

BACKGROUND AND AIMS: In most hospitals in Vietnam, clinical assessment of nutritional status has yet to become part of the routine clinical history taking and physical examination. It is the aim of this study to apply subjective global assessment (SGA) of nutritional status in surgical patients in the Mekong Delta, Vietnam, to determine the incidence of malnutrition according to SGA and to know whether there was an association between SGA class and infectious complications. METHODS: A prospective, cross-sectional study design was used. SGA of nutritional status was applied. Patients were rated as well nourished (A), moderately malnourished (B) or severely malnourished (C). Infectious complications (wound infection, intra-abdominal abscesses, anastomotic leakage) were recorded. RESULTS: Of the 438 patients assessed, 194 (44.3%) were classified as A, 126 patients (28.8%) were classified as B and 118 patients (26.9%) were classified as C. Of the 274 patients who underwent major abdominal surgery assessed, 61 patients (22.3%) were classified as A, 97 patients (35.4%) were classified as B and 116 patients (42.3%) were classified as C. Weight loss and percent weight loss, muscle wasting, loss of subcutaneous fat, functional capacity and significant gastrointestinal symptoms correlate significantly with the severity of SGA class (P<0.001). The rate of postoperative infectious complications was higher in patients classified as SGA class C (33.6%) than as class A (6%) and B (11%). CONCLUSIONS: A high rate of malnutrition was found, applying SGA of nutritional state in surgical patients in Vietnam. Malnutrition was associated with an increase in infectious complications. Special attention should be paid to weight loss, muscle wasting, loss of subcutaneous fat, functional capacity and gastrointestinal symptoms.

Bio-electrical impedance spectroscopy: alternatives for the conventional hand-to-foot measurements.

BACKGROUND AND AIMS: Bio-impedance spectroscopy (BIS) is a very attractive method for measuring body composition. The standard method measures impedance from hand to foot. However, in patients a hand or foot is not always accessible. In these cases alternative methods would be helpful. The objective of this study was to compare BIS measurements from hand to foot (HF) with foot to foot (FF) and hand to hand (HH) measurements as alternatives. Aims were firstly, to assess the relationship between resistance (R) values measured by the different methods, secondly, to study the influence of body geometry on this relationship and lastly, to assess the predictive capacity of the methods for measuring body fluid volumes. METHODS: In 53 subjects with different degrees of obesity (mean BMI = 38; SD = 9 kg/m(2)) three BIS measurements were performed from HF, HH and FF with a Xitron 4000B machine. Resistances of extracellular (Recw) and intracellular water (Ricw) were extrapolated by fitting the data to a Cole-Cole plot. Total body water (TBW) and extracellular water (ECW) were measured by deuterium and bromide dilution respectively. Intracellular water (ICW) was calculated as TBW-ECW. Anthropometric measurements, including length and circumference of limbs and trunk, were performed as measures for body geometry. RESULTS: The Recw, Ricw and R50 values of HF measurements could be accurately described as a function of the Recw, Ricw and R50 values of HH or FF measurements. The relative circumference of arms and legs and the length of the trunk influenced the relationship between R values of the three different measurements. The degree of overweight did not affect this relationship. The precision of the predictions of TBW, ECW and ICW based on R values of the HH measurements were comparable with the traditional HF measurements while the FF measurements gave slightly less accurate results. CONCLUSIONS: Under circumstances where total body BIS measurements cannot be performed, FF or HH measurements may be used as alternatives. However, for clinical use the effect of changes in fluid distribution on the accuracy of these methods needs to be studied further.

Case study of the clinical usefulness of bioelectrical impedance spectroscopy in evaluating nutritional status.

Bioelectrical impedance spectroscopy (BIS) can be a valuable tool in assessing changes in body composition. Although the validity of BIS in healthy subjects is relatively good, in patients considerably larger measurement errors have been reported. In this article the clinical usefulness of BIS in assessing nutritional status of one case study will be discussed. Interpretation of the predictions of BIS in this unstable patient was difficult. This is in agreement with the consensus that BIS does not give accurate prediction of body composition in individual patients. It is recommended that validation studies of BIS should focus on clinical aspects which can influence BIS measurements.