Leon C. Chesley

Hypertensive disorders in pregnancy

Hypertensive disorders in pregnancy are the leading cause of maternal death in the United States and in many other parts of the world. A recent prospective study has indicated that the susceptibility to preeclampsia-eclampsia is inherited and probably is determined by a single recessive gene. However, the causes are still unknown. The incidences, prevalences, definitions, cardinal signs, and patients at increased risk for hypertensive disorders in pregnancy are discussed. Successful management of these disorders is early detection. Further discussions are made on the management of preeclampsia, eclampsia, and chronic hypertension in regard to treatment, intrapartum course, and maternal and perinatal outcome.

Plasma and red cell volumes during pregnancy

Abstract A reduction in plasma volume with hemoconcentration occurs during eclampsia and pre-eclampsia, roughly in proportion to the severity of the disease. There is some indication that the subnormal plasma volume may antedate the appearance of hypertension, proteinuria, and edema.

Genetics of hypertension in pregnancy: possible single gene control of pre‐eclampsia and eclampsia in the descendants of eclamptic women

Summary. Our report concerns the incidences of pre‐eclampsia and eclampsia in 147 sisters, 248 daughters, 74 granddaughters, and 131 daughters‐in‐law of women who have had eclampsia. The disorder is highly heritable. We have analysed the data in two ways, firstly, as a single gene condition and, secondly, as a multifactorial condition. The observed incidences fit closely with the single gene model with frequency of the putative gene being 0.25. When Falconers method of estimating heritabilities of discrete characters is used, estimates of 120% (sisters), 88% (daughters), and 105% (granddaughters)—none significantly different from 100%—are obtained. Insofar as possible, our definition of pre‐eclampsia corresponds with EPH in the descriptive classification of the Organisation Gestosis and to ‘severe pre‐eclampsia’ in Nelsons classification. The women were delivered in many different hospitals, however, and many records fail to provide all of the essential information

The remote prognosis of eclamptic women

Abstract All but three of the 270 women surviving eclampsia at the Margaret Hague Maternity Hospital in the period 1931 through 1951 were traced to 1973–1974. Seventy-six have died and 13 were not re-examined. In white women having eclampsia in the first pregnancy carried to viability the remote mortality rate is not increased over that in unselected women; in white women having eclampsia as multiparas and in all black women the remote mortality rate is from 2 to 5 times the expected numbers. Primiparous eclamptic women are not different from women matched for age, in several epidemiologic studies, in the prevalence of hypertension or in the frequency distributions of systolic and diastolic blood pressures. There is, however, a considerable increase in the prevalence of hypertension among women having had eclampsia as multiparas and that has accounted for their increased remote death rates. The prevalence of diabetes, developing many years after eclampsia, is 2.5 times the expected rate in primiparous and about 4 times the expected rate among multiparous eclamptic women. Eclampsia neither is a sign of latent essential hypertension nor causes hypertension. Hypertensive pregnancies following eclampsia indicate the probability of later chronic hypertension, but do not cause it.

The remote prognosis of eclamptic women. Sixth periodic report

All but three of the 270 women surviving eclampsia at the Margaret Hague Maternity Hospital in the period 1931 through 1951 were traced to 1973-74. Seventy-six have died and 13 were not re-examined. In white women having eclampsia in the first pregnancy carried to viability the remote mortality rate is not increased over that in unselected women; in white women having eclampsia as mulitparas and in all black women the remote mortality rate is from 2 to 5 times the expected numbers. Primiparous eclamptic women are not different from women matched for age, in several epidemiologic studies, in the prevalence of hypertension or in the frequency distributions of systolic and diastolic blood pressures. There is, however, a considerable increase in the prevalence of hypertension among women having had eclampsia as multiparas and that has accounted for their increased remote death rates. The prevalence of diabetes, developing many years after eclampsia is 2.5 times the expected rate in primiparous and about 4 times the expected rate among multiparous eclamptic women. Eclampsia neither is a sign of latent essential hypertension nor causes hypertension. Hypertensive pregnancies following eclampsia indicate the probabilty of later chronic hypertension, but do not cause it.

Genetic control of susceptibility to eclampsia and miscarriage

Summary. An analysis has been made of 48 pedigrees selected (ascertained) through an affected mother in the first generation. These pedigrees mainly involve cases of eclampsia which occurred before its recent decline in incidence. The data confirm the genetic determination of susceptibility indicated by published data on eclampsia/preeclampsia. There is a suggestion that the fetal genotype can contribute to susceptibility to eclampsia in its mother, in contrast to previous findings that susceptibility to pre‐eclampsia is controlled solely by the maternal genotype. An association between eclampsia and miscarriage is shown in the data. We argue that this suggests that the primary mode of action of the gene(s) involved is to affect the interaction between uterine and placental tissue.

Renal glomerular and tubular function in relation to the hyperuricemia of pre-eclampsia and eclampsia

Abstract Perhaps the most outstanding change in the blood chemistry in eclampsia and pre-eclampsia is in the uric acid, which usually increases. Stander and Cadden,1 from a study of 148 cases, concluded that the blood uric acid “… gives us an accurate index of the severity of pre-eclampsia and the extent of liver damage, if present … and thus is our best criterion for any given type of treatment.” As is implied in the quotation, these workers considered that hyperuricemia points to impairment of liver function. The factors which, if uncompensated, would make for hyperuricemia are: 1. 1. Increased production of uric acid in the body. 2. 2. Decreased renal excretion. 3. 3. Decreased destruction of uric acid in the body. The question as to increased production of uric acid in pre-eclampsia remains unanswered, and almost unasked. As for the second factor, Cadden and Stander2 reported normal excretion in five cases of eclampsia. By “normal excretion” they meant that the eclamptics, on a purine-free diet, excreted from 130 to 740 mg. of uric acid per twenty-four hours. This they compared with the 300 to 500 mg. excretion which Burian and Schur3 found in normal individuals. As we shall show in the discussion below, these data of Cadden and Stander may be reinterpreted. Schaffer, Dill, and Cadden4 have measured simultaneously the clearances of diodrast, inulin, urea, and uric acid in normally pregnant and in pre-eclamptic women. They found that in pre-eclampsia the uric acid clearance averaged 31 per cent less than in their normals. They attributed the diminished uric acid clearance to a decrease in glomerular filtration (which showed a reduction of 20 per cent). Their data are open to the objection that they measured their clearances in the presence of plasma diodrast concentrations of the order of 1 to 2 mg. per 100 ml. Such plasma levels of diodrast will increase the uric acid clearance two- to threefold.5, 6 It is uncertain whether diodrast would have quantitatively the same effect upon the pre-eclamptic kidney as upon the normal. Furthermore, detailed study of their data for individual cases leaves one unconvinced that a reduction in the filtration rate is chiefly responsible for the decreased uric acid clearances. Recalculation of their data shows a more general factor—in pre-eclampsia there seems to be an increased tubular reabsorption of filtered uric acid. (Uric acid is filterable from human plasma.7) In the present paper we are reporting the measurements of simultaneous clearances of inulin, urea, and of uric acid as determined by two methods. Inulin does not affect the uric acid clearance.5

Pregnancy in the patient with hypertensive disease.

W E HAVE thought it worth while to survey our experience with pregnancy in women with hypertensive disease. There are relatively few such studies based upon any considerable series, and in most studies extant there has been a selective factor in that therapeutic abortion has been done in the more severely hypertensive patients. It has not been our policy lo abort such women, and our large material therefore offers an almost unique opportunity for the study of’ the natural history of pregnancy in hypertensive women.

Clinical significance of elevated mean arterial pressure in the second trimester

Several reports suggested using the mean arterial blood pressure during the second trimester to predict the future development of preeclampsia. The value of a second-trimester mean arterial blood pressure greater than or equal to 90 mm Hg was reviewed in 39,876 reported cases of preeclampsia and 207 cases of eclampsia. The sensitivity ranged from 0% to 92% and the specificity varied from 53% to 97%. The predictive value of a positive test ranged from 0% to 43% and the predictive value of a negative test ranged from 76% to 98%. The predictive value of a positive test was not greatly higher than the incidence of hypertension in the whole population studied in the majority of the reports. There was a strong association of higher second-trimester mean arterial blood pressure in nulliparous women with eclampsia who had transient hypertension in later gestations and ultimately developed chronic hypertension. The data suggest that one sign of future chronic hypertension, that is, transient hypertension, is often predicted by high second-trimester mean arterial blood pressure, which may have the same significance. We think that if increased second-trimester mean arterial blood pressure levels predict anything, it is transient hypertension rather than preeclampsia-eclampsia.

THE CONCENTRATIONS OF PROTEASES, AMYLASE, AND LIPASE IN CERTAIN MARINE FISHES

Marine fishes show great diversity as to food, feeding habits, special habitat, and rate and type of metabolism. Some have predominantly a fatty metabolism while others have essentially a carbohydrate metabo lism in the sense that the nutritive reserves are stored in the form of fat or carbohydrates. Certain fishes, such as the mackerel, are ex tremely active; others are very sluggish; still others represent all the intergrades. Great variation is shown as to the development of the differentorgans concerned with digestion;in some fishesthe pancreas is more or less clearly defined, in others it is diffuse and may be partially included in the liver. Pyloric c@ca, which are the embryological equiv alent of the exocrine pancreas, may also be its physiological equivalent in some cases. These structures are absent in many fishes. As these factors vary, it is to be expected that there will be adaptive variations in the amounts and sites of production of the different di gestive enzymes secreted. It is the purpose of this investigation to determine where the enzymes are secreted, and in what quantities, with a view to making correlations with the anatomy and physiology of the fishes studied. The early literature bearing upon digestion in fishes is well reviewed by Yung (1899) and Sullivan (1907). The rate of digestion has been studied by Van Slyke and White (1911). They state that in the dogfish two to three days are required for the disposal of a meal; this is about six times as long as the period in mammals, which may be due to the temperature difference. Svolima (1919) found the period of digestion to last up to five days. Yung (1899) had set the period at ten hours. Kenyon (1925) compared digestion in the different classes of verte brates. Peptic digestion he found to be remarkably uniform among all the animals investigated, with the exception of the stomachless carp. Gastric acidity is exceedingly variable, apparently depending upon the functional state of the organ. There seems to be no correlation between peptic activity and food habits. There is a close correlation between the 133