Effect Of Body Habitus Research Articles

151: Effect of Body Habitus and Parity on Insufflated CO 2 Volume during Laparoscopic Access in Women

151: Effect of Body Habitus and Parity on Insufflated CO 2 Volume during Laparoscopic Access in Women

Effects of Obesity and Small Body Size on Operative and Long-Term Outcomes of Coronary Artery Bypass Surgery: A Propensity-Matched Analysis

The effects of body habitus on coronary artery bypass graft surgery (CABG) operative and long-term outcomes are not well defined. We aimed to elucidate the independent effects of small body size and obesity on CABG outcomes. Primary isolated CABG patients were grouped based on body surface area (BSA, m2) and body mass index (BMI, kg/m2) as follows: 611 very small (BSA < or = 1.70); 933 slightly small (1.70 < BSA < or = 1.85); 945 moderately obese (32 < BMI < 36); 594 very obese (BMI > or = 36); and 3,018 normal (BSA >1.85; BMI = 22 to 32). Subcohorts of very small (371 pairs, 61%), slightly small (717, 77%), moderately obese (874, 92%), and very obese (516, 87%) patients were propensity-matched to normal. Compared with normal, very small had more transfusions (46% versus 32%; p < 0.001), reoperation for bleeding (3.2% versus 0.3%; p = 0.002), and pulmonary edema (2.4% versus 0.5%; p = 0.033). For slightly small, transfusion (41% versus 29%; p < 0.001) and bleeding (2.5% versus 1.0%; p = 0.04) were increased. For moderately obese, sternal wound infections (1.9% versus 0.8%; p = 0.04) were greater. Complications were most frequent in very obese: reoperation (5.2% versus 1.6%; p < 0.001), sternal wound infections (3.5% versus 0.2%; p < 0.001), pulmonary edema (2.9% versus 1.2%; p = 0.047), renal failure (6.0% versus 2.3%; p = 0.003), atrial fibrillation (20% versus 12%; p = 0.001), gastrointestinal problems (3.7% versus 1.6%; p = 0.032), and postoperative stay (8.0 versus 6.4 days; p = 0.003). When slightly small and very small are considered together, operative mortality was significantly greater (3.22% versus 1.65%; p = 0.026). Both very small (risk ratio [RR] = 1.39; p = 0.044) and very obese (RR = 1.44; p = 0.020) were independent predictors of worse 0- to 12-year mortality. Large deviations from normal body size in either direction--particularly extreme obesity--are associated with increased postoperative morbidity and worse long-term survival.

Improved echocardiographic detection and characterization of left ventricular apical thrombi with a 5.0 MHz short-focus transducer.

Transthoracic echocardiography is a frequently used technique for detecting ventricular thrombi. This study compares the usefulness of a 5.0 MHz short focal length transducer (5-short) with standard frequency (2.5 or 3.5 MHz) transducers for the detection of left ventricular thrombi. In addition, the effect of body habitus on study quality was evaluated. A consecutive series of 101 patients sent for echocardiographic imaging with the diagnosis of myocardial infarction, dilated cardiomyopathy, or recent suspected embolic event were imaged in the apical four-chamber, apical long-axis, and apical two-chamber views with a standard transducer and also with the 5-short. Out of this group, 16 apical thrombi were identified, six with the 5-short only, three with standard transducers only, and seven by both techniques. The areas of the seven thrombi detected by both transducers were consistently larger when measured on 5-short images compared with standard transducer images (4.6 +/- 2.3 vs 3.7 +/- 2.3 cm2, p = 0.02). In the three studies positive only with the standard transducers, the 5-short demonstrated only prominent trabeculae but no thrombus. The studies positive only with the 5-short had significantly smaller calculated thrombi areas than those visualized by the standard transducers (1.6 +/- 1.2 vs 4.2 +/- 2.1 cm2, p = 0.02). No thrombus was detected by either technique in a normally contracting left ventricular apex. There were significantly fewer studies having near-field artifact when performed by the 5-short compared with those performed with standard transducers (14/101 vs 40/101, p = 0.00004).(ABSTRACT TRUNCATED AT 250 WORDS)

Calibration and evaluation of a 252CF-based neutron activation analysis instrument for the determination of nitrogen in vivo

A novel clinical instrument for multi-element in vivo neutron activation analysis has been recently constructed in Swansea. The instrument is intended primarily for prompt gamma measurement of total and partial body calcium, total body nitrogen and partial body cadmium. For the measurement of nitrogen the subject is scanned both prone and supine across a vertical collimated neutron beam from a 4 GBq 252Cf source. Two shielded NaI(Tl) detectors, each of volume 2760 cm3, are placed above the subject on the opposite side to that irradiated. The prompt gamma ray spectrum contains prominent peaks from hydrogen, nitrogen, chlorine and carbon. The optimisation, calibration and evaluation of the instrument for the measurement of nitrogen, by the reaction 14N(n, gamma )15N, is described. The calibration corrects the ratio of nitrogen-to-hydrogen counts measured from the subject for background gamma rays and the effects of body habitus. Body hydrogen is used as an internal standard. Repeated measurements of a homogeneous anthropomorphic phantom indicate that the ratio of nitrogen-to-hydrogen counts may be determined with a coefficient of variation of 1.6% for a neutron dose equivalent incident on the phantom of 0.45 mSv (QF=10). The accuracy of the calibration was assessed by measuring three anthropomorphic phantoms (weight range: 41.4-110 kg) containing simulated skeletons and the major organs of the body. For these phantoms the mean discrepancy of the measured to the known nitrogen content was +4.9%. The simultaneous measurement of chlorine and carbon is discussed.