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991.
Background: Critically ill patients commonly experience skeletal muscle wasting that may predict clinical outcome. Ultrasound is a noninvasive method that can measure muscle quadriceps muscle layer thickness (QMLT) and subsequently lean body mass (LBM) at the bedside. However, currently the reliability of these measurements are unknown. The objectives of this study were to evaluate the intra‐ and interreliability of measuring QMLT using bedside ultrasound. Methods: Ultrasound measurements of QMLT were conducted at 7 centers on healthy volunteers. Trainers were instructed to perform measurements twice on each patient, and then a second trainee repeated the measurement. Intrarater reliability measured how consistently the same person measured the subject according to intraclass correlation (ICC). Interrater reliability measured how consistently trainer and trainee agreed when measuring the same subject according to the ICC. Results: We collected 42 pairs of within operator measurements with an ICC of .98 and 78 pairs of trainer‐to‐trainee measurements with an ICC of .95. There were no statistically significant differences between the trainer and trainee results (trainer and trainee mean = ?0.028 cm, 95% CI = ?0.067 to ?0.011, P = .1607). Conclusions: Excellent intra‐ and interrater reliability for ultrasound measurements of QMLT in healthy volunteers was observed when performed by a range of providers with no prior ultrasound experience, including dietitians, nurses, physicians, and research assistants. This technique shows promise as a method to evaluate LBM status in ICU or hospital settings and as a method to assess the effects of nutrition and exercise‐based interventions on muscle wasting.  相似文献   
992.
Background and Objective: Handgrip strength is a relevant marker of functional status and is also a component of nutrition assessment. The simplicity of this measurement supports its usefulness as a tool to predict who will likely take longer to hospital discharge. The aim of this study was to quantify the association between sex‐specific handgrip strength at hospital admission and time to discharge alive. We intended to include a group of diverse diagnoses and to compare medical and surgical wards, taking into account the potential confounders’ effect of patients’ characteristics and severity of disease. Subjects and Methods: Prospective study in 2 public acute‐care general hospitals in Porto, Portugal, in 2004. Handgrip strength was evaluated using a handgrip dynamometer in a probability sample of 425 patients from medical and surgical wards. The association between baseline handgrip strength and time to discharge was evaluated using survival analysis with discharge alive as the outcome and deaths and transfers being censored. Results: In medical wards, women with high admission handgrip strength had a very short hospital stay (all had been discharged by the sixth day), and among men, patients with low handgrip strength had a particularly longer stay (approximately 50% were discharged after 15 days of hospitalization). In surgical wards, an increasing length of stay with decreasing handgrip strength quartiles was also observed in both sexes. Conclusions: Lower handgrip strength at hospital admission was associated with a longer time in the hospital, in patients of both sexes, in medical and surgical wards. Although this association was explained in part by age, height, education level, cognitive status, and disease severity, its direction remained unchanged regardless of the aforementioned factors.  相似文献   
993.
Background: Necrotizing enterocolitis (NEC) is a severe inflammatory disorder, associated with the difficult transition from parenteral to enteral feeding after preterm birth. We hypothesized that minimal enteral nutrition (MEN) with amniotic fluid (AF), prior to enteral formula feeding, would improve resistance to NEC in preterm pigs. Methods: Experiment 1: IEC‐6 cells were incubated with porcine (pAF) and human AF (hAF) to test AF‐stimulated enterocyte proliferation and migration in vitro. Experiment 2: Cesarean‐delivered, preterm pigs were fed parenteral nutrition and MEN with pAF, hAF, or control fluid (MEN‐pAF, MEN‐hAF, or MEN‐CTRL; all n = 9) for 2 days before tissue collection. Experiment 3: Preterm pigs were fed MEN diets as in experiment 2, but followed by 2 days of enteral formula feeding, which predisposes to NEC (NEC‐pAF, NEC‐hAF, or NEC‐CTRL; n = 10–12). Results: Both pAF and hAF stimulated enterocyte proliferation and migration in vitro. In experiment 2, MEN‐pAF and MEN‐hAF pigs showed increased body weight gain and reduced intestinal interleukin (IL)–8 and colonic IL‐6 levels, indicating reduced inflammatory response. In experiment 3, body weight gain was highest in the 2 groups fed AF as MEN, but NEC incidences were similar (NEC‐pAF) or increased (NEC‐hAF) compared with controls. Conclusions: Intake of pAF or hAF improved body growth and modulated intestinal inflammatory cytokines during a period of parenteral nutrition, but did not protect against later formula‐induced NEC in preterm pigs. Further studies are required to show if MEN feeding with species‐specific AF, combined with an optimal enteral diet (eg, human milk), will improve adaptation during the transition from parenteral to enteral feeding in preterm neonates.  相似文献   
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