Harlley E. McKean

Blood pressure trends associated with changes in height and weight from early adolescence to young adulthood

In children, blood pressure is more closely related to height and indices of maturation than to age. This study extends observations on the relationship between height, weight, maturation and blood pressure during early adolescence into young adulthood. Standardized measurements of blood pressure, height, and weight were initially obtained in all 14-15 year old adolescents (N = 304) in a rural Kentucky school system. Measurements were repeated 5 and 8 years later. Adolescents with relatively high blood pressures continued to have higher blood pressures as young adults. Increases in systolic and diastolic blood pressure over time were related to increases of relative weight in both sexes (p less than 0.0001 and p less than 0.005, respectively), and in males increases of systolic blood pressure were related to increases of height (p less than 0.005). However, males who attained their full height at younger ages had higher blood pressures both during adolescence and subsequently, as young adults. Thus blood pressure of young adults is related to blood pressure in adolescence, relative weight and change in relative weight since adolescence, and in males to age of maturation as determined by the age at which adult height is attained.

Influence of Potassium Cardioplegia versus Ischemic Arrest on Regional Left Ventricular Diastolic Compliance in Humans

To compare the effects of hypothermic ischemic arrest versus hypothermic potassium cardioplegia, regional left ventricular performance was monitored in 20 adult male patients undergoing saphenous vein bypass operation. Twelve patients received ischemic arrest (Group 1), and 8 received potassium cardioplegia (Group 2). Groups 1 and 2 did not differ in left ventricular ejection fraction (0.62 versus 0.60), number of bypassed vessels (3.7 versus 3.4), mean cross-clamp time (75 versus 63 minutes), or mean cardiopulmonary bypass time (182 versus 170 minutes). Before cardiopulmonary bypass was begun, a pair of ultrasonic crystals was secured in the left ventricular anterior myocardium to measure segment motion and a micromanometer-tipped catheter was placed in the left ventricular chamber. All patients received a saphenous vein bypass graft to a vessel supplying the anterior left ventricular wall in the region of the ultrasonic crystals. Comparison of changes in systolic measurements revealed no significant differences between Groups 1 and 2. After saphenous vein bypass grafting, the left ventricular end-diastolic pressure (11.4 to 17.0 mm HG) and modulus of left ventricular segment stiffness (0.37 to 0.67, p less than 0.02) were elevated in Group 1 but no changes were observed in Group 2 (14.0 to 15.6 mm Hg, and 0.16 to 0.24, respectively). Compared with hypothermic ischemic arrest, hypothermic potassium cardioplegia is not associated with an increased left ventricular diastolic stiffness shortly after saphenous vein bypass grafting in humans.

Diurnal variation of estriol excretion in human pregnancy

Abstract Twenty-one normally pregnant patients had their urinary output fractionated into 4 hour aliquots for a total of 6 days. Each urinary specimen was analyzed for estriol. By using duplicate assays the statistical error was reduced to between 3 and 5 per cent. From these data it is not possible to predict the 24 hour urinary estriol excretion from a single 4 hour period specimen. Even the use of two 4 hour specimens in combination will not successfully predict the 24 hour excretion rate. While diurnal variation clearly exists, it is extremely complex and not simply predictable for a given patient. In these normally pregnant patients, bed rest had no significant influence on urinary estriol excretion rates.

Immunologic reactions and Australia Antigenemia in Down's Syndrome☆

Abstract Immunologic studies were done in sixty institutionalized patients with Downs syndrome (DS) and compared with age and sex matched mentally retarded (MR) controls. In the DS group there was a significant increase in gamma globulins, IgG and IgA. Au antigenemia was found in 27 per cent of DS patients and in none of the controls. In contrast to previous reports there was no evidence of decreased delayed hypersensitivity to PPD, histoplasmin or dermatophytin in DS subjects. There were, however, significantly fewer positive skin tests to mumps antigen. These studies confirmed the previously reported changes in serum proteins and increased prevalence of Australia antigenemia in DS. The results of skin testing and in vitro lymphocyte stimulation (reported elsewhere) did not demonstrate a generalized defect in cellular immunity in DS. The decrease in positive mumps skin reactions and Australia antigenemia may reflect an unusual defect in the handling of viral infections.

1286 IMPROVED PREDICTION OF FETAL LUNG MATURITY IN DIABETIC PREGNANCIES

Following planned termination of pregnancy, infants of diabetic mothers (IDM) have shown a continued vulnerability to the respiratory-distress syndrome (RDS) suggesting false-positive fetal lung maturity testing. Adequacy of the lecithin/sphingomyelin (L/S) ratio for predicting RDS was studied in 56 diabetic (DM) and 50 nondiabetic (ND) pregnancies. Amniotic-fluid samples (n=130) were assayed for 1- and 2-dimensional (dim) thinlayer chromatographic (TLC) L/S ratios, and phosphatidylglycerol (PG) and phosphatidylinositol (PI) assays. L/S ratios for all pregnancies by both TLC techniques revealed higher 1-dim values from 36-38 wk gestation (P<0.01). Per cent PI was increased for ND over DM before 34 wk (P<0.03), otherwise it did not delineate gestational age for either group. PG appeared in the surfactant complex beyond 34 wk (P<0.001), however, when L/S ratios were 2 to 2.9, it appeared in only 16.7% of DM pregnancies vs 50% of ND (P<0.02). PG was absent in 37% of all pregnancies > 38 wk with L/S ratios > 3. PG detection by class of DM was delayed for class A pregnancies beyond 36.5 wk (r=0.6551, P<0.007). Respiratory distress developed in 3 infants (2.9%): 2 ND had transient tachypnea (1.9%), 1 IDM had RDS (0.95%). We conclude: 1) 2-dim TLC improves phosphatide identification, 2) PG, if present, confirms fetal lung maturity in conjunction with positive L/S ratios, and 3) the L/S ratio remains the best available indicator of fetal lung maturation, irrespective of maternal diabetes.