Hemodynamic assessment of radial-arterial pressure-wave contours in children.

A new classification system for the radial-arterial pressure-wave contour in children is proposed with respect to their hemodynamic parameters. The contour of the radial-arterial pressure wave was analyzed in 45 children who had undergone open heart surgery. Stroke volume and peripheral vascular resistance were calculated from the cardiac output by thermodilution. The arterial pressure-wave contours were classified into type I, II or III, with each wave type having three, two and one shoulders, respectively. Type I denoted a better cardiac index, with a lower heart rate and larger stroke volume than type II. Type III was symptomatic of low cardiac output. Type I was further classified into subgroups Ia and Ib according to the magnitude of the tidal wave, and type II was subdivided into IIa and IIb according to the magnitude of the dicrotic notch. The classification of subgroup types a and b in both types I and II was related to the degree of vascular contraction. It is concluded that monitoring of the arterial pressure-wave contours provides useful information regarding hemodynamics in children.

Proliferative activity of human tumors: assessment using bromodeoxyuridine and flow cytometry.

Cell kinetics of human carcinoma xenografts and human solid tumors were evaluated by means of two-color flow cytometry using single sampling at appropriate time intervals after bromodeoxyuridine (BrdU) labeling. The tumors were resected several hours after the administration of BrdU, and flow cytometry was used to measure the DNA content and BrdU incorporation. Once the BrdU labeling index (LI) and DNA synthesis time (Ts) were obtained, the potential doubling time (Tpot) was calculated from these values. In 11 xenografts, the cell kinetic data were compared with the actual tumor doubling time (Td), and a good correlation between Tpot and Td was obtained (r = 0.91, P less than 0.005). In a clinical study, 33 patients with gastric cancer, colorectal cancer, lung cancer, or other solid tumors were analyzed. Aneuploid tumors had a significantly higher LI value (P less than 0.01) and a shorter Tpot than diploid tumors. The cell loss rate of human tumors ranged from 40% to 80%. These cell kinetic parameters therefore accurately indicated the level of proliferative activity of human tumors.

Modified Blalock-Taussig shunt operation without cardiac catheterization: two-dimensional echocardiographic preoperative assessment in cyanotic infants.

Between May 1981 and December 1983, 25 infants with cyanotic congenital heart defects underwent 26 Blalock-Taussig shunt operations without cardiac catheterization and angiocardiography. In these infants, the diagnosis was established by 2-dimensional echocardiography (2-D echo) supplemented with clinical findings, chest x-ray and electrocardiography. The right and left pulmonary artery measurements, a prerequisite for a shunt operation, determined by 2-D echo were compared with those at surgery and had an excellent correlation (r = 0.94). No infant died as a consequence of an early shunt failure, and only 1 died of postoperative pyothorax. In conclusion, 2-D echo may eliminate the need for invasive investigation in selected patients undergoing the Blalock-Taussig anastomosis.