The Journal of surgical research
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A common method for calculating energy needs (PEE) in acute trauma patients is multiplying the Harris-Benedict equation (BEE) by activity factors (AF) and variable stress factors (SF) depending on the injury severity. Selection of the SF can be an arbitrary and potentially inaccurate decision. The purposes of this study were: (1) to investigate the relationship between injury severity score (ISS) to postinjury energy expenditure (MEE), and (2) to compare the MEE to PEE when using the SF of 1.75. ⋯ There was a significant correlation (r = 0.772, P < 0.05) between PEE and MEE when using the SF of 1.75 for all of the patients. These results suggest that there is not a correlation between ISS and subsequent MEE in major trauma patients. In addition, using the SF of 1.75 will closely estimate energy needs in acute trauma patients.
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A thoracic electric bioimpedance device with improved signal processing was used to noninvasively measure cardiac output in eight New Zealand White rabbits (average wt = 4.7 kg). Prospective correlation was performed between aortic thermodilution and impedance cardiography in a closed chest model. Aortic thermodilution was compared to the electromagnetic flowmeter in an open chest model. ⋯ A statistically significant decline in the mean magnitude of the dZ/dt signal tracing (1.6 +/- 0.10 V-pre, 0.31 +/- 0.4 V-post, P < 0.005, n = 21) was observed upon aortic arch occlusion. conversely, pulmonary artery occlusion did not have a statistical effect on the impedance signal (1.07 +/- 0.09-pre, 0.95 +/- 0.08-post, P > 0.05, n = 20). In conclusion, a significant correlation was observed between impedance cardiography and aortic thermodilution in measurement of cardiac output in sedated, anesthetized rabbits. This simple technique which involves application of skin electrodes may prove useful in measurement of cardiac output in surgical experimental small animal models.(ABSTRACT TRUNCATED AT 250 WORDS)