Effect of Body Position on Energy Expenditure of Preterm Infants as Determined by Simultaneous Direct and Indirect Calorimetry.

Background Indirect calorimetry is the standard method for estimating energy expenditure in clinical research. Few studies have evaluated indirect calorimetry in infants by comparing it with simultaneous direct calorimetry. Our purpose was (1) to compare the energy expenditure of preterm infants determined by these two methods, direct calorimetry and indirect calorimetry; and (2) to examine the effect of body position, supine or prone, on energy expenditure. Study Design We measured energy expenditure by simultaneous direct (heat loss by gradient-layer calorimeter corrected for heat storage) and indirect calorimetry (whole-body oxygen consumption and carbon dioxide production) in 15 growing preterm infants during two consecutive interfeeding intervals, once in the supine position and once in the prone position. Results The mean energy expenditure for all measurements in both positions did not differ significantly by the method used: 2.82 (standard deviation [SD] 0.42) kcal/kg/h by direct calorimetry and 2.78 (SD 0.48) kcal/kg/h by indirect calorimetry. The energy expenditure was significantly lower, by 10%, in the prone than in the supine position, whether examined by direct calorimetry (2.67 vs. 2.97 kcal/kg/h, p < 0.001) or indirect calorimetry (2.64 vs. 2.92 kcal/kg/h, p = 0.017). Conclusion Direct calorimetry and indirect calorimetry gave similar estimates of energy expenditure. Energy expenditure was 10% lower in the prone position than in the supine position.

Effectiveness of a dynamic breast examination training model to improve clinical breast examination (CBE) skills.

Despite the potential utility of clinical breast examination (CBE), doctors' palpation skills are often inadequate and difficult to train. CBE sensitivity ranges from 39-59%, in part because current training does not effectively teach tactile skills. To address CBE training limitations, we developed a breast examination training model with 15 dynamically controlled lumps, set to desired hardness within underlying rib and muscle structures, in a silicone breast. In an experiment of 48 medical students, training with the dynamic model increased lump detection by 1.35 lumps compared to 0.60 lumps for a traditional breast model (P=0.008), reduced false positives by -0.70 lumps compared to +0.42 lumps (P=0.0277), and demonstrated skill transfer with a 1.17 lump detection improvement on the traditional device compared to only a 0.17 lump detection improvement by traditional device trainees on the dynamic device (P<0.001). Findings demonstrate the advantage of the dynamic model over conventional models in training CBE tactile skills.