R.E. Pottinger

Etiology of eclampsia

Abstract We have not been able by obstetric and dietetic care to reduce the incidence of pre-eclampsia or prevent the development of an occasional case of eclampsia. The elimination of water given by the oral or intravenous route is delayed in all pregnant patients but more markedly in those with pre-eclampsia than in those who have hypertensive disease. This delay may be due in part to the increased storage of the water in the legs and thighs as a result of the high venous pressure in the lower extremities due to the pregnancy. The antidiuretic substance from the posterior pituitary and the hormones from the adrenal cortex are also involved but the mechanism of control is still in doubt. A urinary volume of 2,000 ml. per twenty-four hours is recommended as requiring minimal work by the normal kidney. The hourly ingestion of water in constant amounts of 150 to 200 ml. seems to produce better elimination of water, electrolyte and nonelectrolyte substances than the irregular ingestion of large amounts. It seems advisable to instruct normal patients not to ingest more than 1 to 2 Gm. of sodium, 4 to 6 Gm. of chloride, and 1 to 2 Gm. of potassium per twenty-four hours during pregnancy.

Protein excretion patterns in pregnancy

Abstract Serum and urinary protein fractions were determined simultaneously in a group of normal and abnormal pregnant patients by electrophoretic separation. A comparison of these urinary and serum protein fractions revealed differences in the pattern of urinary protein excretion which suggest that this method affords a means for differentiating the entities associated with proteinuria in pregnancy.

Alterations in body composition during pregnancy.

Abstract Gross body composition, sodium 22 space, and exchangeable sodium were determined in normal and abnormal pregnant patients. The pattern of alteration in gross body composition which characterized normal pregnant patients, individuals who evidenced excessive weight gain as the only clinical abnormality, individuals with hypertensive disease, and patients with pre-eclampsia-eclampsia are presented. The individuals with pre-eclampsia-eclampsia were unique in that they evidenced marked antepartum and postpartum increases in the proportion of exchangeable sodium contained in their fat-free bodies. It was suggested that this combination of antepartum and postpartum changes may constitute a physicochemical definition of pre-eclampsia-eclampsia.

Total exchangeable sodium and space in normal and pre-eclamptic patients determined with sodium: Preliminary report

Abstract Radiosodium 22 with a half-life of 3 years is the ideal substance for determining the amount of sodium in the body and its elimination. The equilibration for sodium 22 as determined by the serum concentration and the total amount remaining in the body depends upon the sodium intake for the preceding period and days following the injection. The sodium space in patients who are ingesting 4 or more Gm. of sodium salts per day probably never reaches equilibrium. In the patient on a sodium intake of 4 or more Gm. per 24 hours, the radioactive sodium is no longer detectable by 14 weeks but in the patient on a sodium intake of less than 2 grams per 24 hours, the sodium was still determinable at the end of 18 weeks, and with a still smaller intake of sodium the turnover was still slower, reaching approximately 22 weeks. In the normal subject on an average or high intake of sodium chloride, although the turnover is more rapid, approximately 13 per cent of the injected sodium 22 at the end of 14 weeks is still unaccounted for and is probably stored in bone. A basis for comparing values between pregnant patients is extremely difficult, and will probably have to be based upon the total body water in the lean body mass. The sodium space is increased in normal pregnancy and markedly increased in pre-eclamptic patients and to a lesser degree in the hypertensive disease group. This is true whether one calculates it as the total sodium space, as the milliliters per kilogram, per centimeter of height, or per square meter of body surface. The total exchangeable sodium is increased approximately 10 per cent in the normal pregnant patient and is markedly increased in the pre-eclamptic patient as evidenced by a 32 per cent drop by the eighth postpartum day. The hypertensive disease group is characterized by a larger amount of total exchangeable sodium but if calculated on a per kilogram basis then the values are less than normal, indicating that fat does not contain as much water and electrolyte as does the lean body tissue.

Etiology of pre-eclampsia-eclampsia

Abstract In the normal pregnant patient when compared with the nonpregnant, the following significant changes are noted: Muscle: The water content is unchanged. Sodium is increased. Potassium remains unchanged. The Na:K ratio is increased. The nitrogen content is unchanged. Skin: Sodium and water are increased. Potassium is unchanged. The Na:K ratio is unchanged. Nitrogen is slightly lower in wet tissue. In the patient with pre-eclampsia or hypertensive disease when compared with normal pregnancy the following significant changes are noted: Muscle: Water is unchanged. Sodium is decreased in pre-eclampsia and hypertensive disease (similar to nonpregnancy values). Potassium is unchanged. The Na:K ratio is less in pre-eclampsia than in hypertensive disease. Nitrogen content is unchanged. Skin: Water is unchanged. Sodium is decreased in pre-eclampsia and hypertensive disease (similar to nonpregnancy values). Potassium is unchanged. The Na:K ratio is unchanged. Nitrogen in wet tissue is higher from the hypertensive patient than from the normal pregnant or pre-eclamptic patient. These results on the sodium content of rectus muscle in pre-eclampsia-eclampsia and hypertensive disease were at variance with published reports and were surprising to us since a hypernatremic muscle offered more opportunity for theorizing. Three separate groups of analysis confirmed this finding. The explanation awaits further studies. The clinical application was illustrated by three eclamptic patients, each of whom was made markedly worse by the wrong solution and the injudicious administration of excessive fluids. Our studies indicate that in pre-eclampsia and hypertensive disease there is a significant decrease in the sodium ion concentration of voluntary muscle with a resultant alteration in the sodium-potassium ratio when compared with those of tissues obtained from normal pregnant patients. The fact that the values are essentially those of the nonpregnant woman does not detract from their abnormality.

The inactivation of the antidiuretic hormone of the posterior pituitary gland by blood from pregnant patients

Abstract A simple method is presented for evaluating the antidiuretic effect of solution of posterior pituitary, using human subjects for the experiments. Our studies indicate that when Pitressin is incubated with blood from patients in the last half of pregnancy, the antidiuretic effect of Pitressin is absent or markedly diminished. Incubation with blood from nonpregnant patients evokes little change.

Etiology of pre-eclampsia-eclampsia: VI. Sodium, potassium, nitrogen, and water content of muscle and skin in pre-eclampsia☆☆☆

In the normal pregnant patient when compared with the nonpregnant, the following significant changes are noted: Muscle: The water content is unchanged. Sodium is increased. Potassium remains unchanged. The Na:K ratio is increased. The nitrogen content is unchanged. Skin: Sodium and water are increased. Potassium is unchanged. The Na:K ratio is unchanged. Nitrogen is slightly lower in wet tissue. In the patient with pre-eclampsia or hypertensive disease when compared with normal pregnancy the following significant changes are noted: Muscle: Water is unchanged. Sodium is decreased in pre-eclampsia and hypertensive disease (similar to nonpregnancy values). Potassium is unchanged. The Na:K ratio is less in pre-eclampsia than in hypertensive disease. Nitrogen content is unchanged. Skin: Water is unchanged. Sodium is decreased in pre-eclampsia and hypertensive disease (similar to nonpregnancy values). Potassium is unchanged. The Na:K ratio is unchanged. Nitrogen in wet tissue is higher from the hypertensive patient than from the normal pregnant or pre-eclamptic patient. These results on the sodium content of rectus muscle in pre-eclampsia-eclampsia and hypertensive disease were at variance with published reports and were surprising to us since a hypernatremic muscle offered more opportunity for theorizing. Three separate groups of analysis confirmed this finding. The explanation awaits further studies. The clinical application was illustrated by three eclamptic patients, each of whom was made markedly worse by the wrong solution and the injudicious administration of excessive fluids. Our studies indicate that in pre-eclampsia and hypertensive disease there is a significant decrease in the sodium ion concentration of voluntary muscle with a resultant alteration in the sodium-potassium ratio when compared with those of tissues obtained from normal pregnant patients. The fact that the values are essentially those of the nonpregnant woman does not detract from their abnormality.

Etiology of pre-eclampsia-eclampsia. III. The effect of oral ingestion of sodium chloride and sodium bicarbonate by patients with toxemia of pregnancy.

Abstract Pregnant patients who showed too rapid weight gain, edema, hypertension, proteinuria, or various combinations of these signs were given sufficient identical 1 Gm. tablets ∗ of sodium chloride, sodium bicarbonate, ammonium chloride, or a placebo. Instructions were that they were to take 7 tables per day for one or more weeks and each patient was, if possible, to have taken the series of 4 tablets. In some patients, presumably those with true pre-eclampsia, the sodium ion, especially as sodium chloride, caused a definite increase in the weekly gain in weight, in the degree of edema, in the blood pressure, and in the proteinuria. However, in about 70 per cent of the patients there was no difference in the response to any of the four substances used. These studies of the oral and intravenous injection of sodium salts indicate that many patients who have signs of toxemia do not have true pre-eclampsia. We suggest the term “pseudo pre-eclampsia.” It is a waste of time to restrict the sodium intake of patients with pseudo pre-eclampsia as well as of many patients with hypertensive disease. Our work indicates a need for a better selection of patients and a more rigid restriction of the sodium ion in patients with true pre-eclampsia.

American Gynecological Society Transactions of the Eightieth Annual MeetingTotal exchangeable sodium and space in normal and pre-eclamptic patients determined with sodium: Preliminary report☆☆☆

Abstract Radiosodium 22 with a half-life of 3 years is the ideal substance for determining the amount of sodium in the body and its elimination. The equilibration for sodium 22 as determined by the serum concentration and the total amount remaining in the body depends upon the sodium intake for the preceding period and days following the injection. The sodium space in patients who are ingesting 4 or more Gm. of sodium salts per day probably never reaches equilibrium. In the patient on a sodium intake of 4 or more Gm. per 24 hours, the radioactive sodium is no longer detectable by 14 weeks but in the patient on a sodium intake of less than 2 grams per 24 hours, the sodium was still determinable at the end of 18 weeks, and with a still smaller intake of sodium the turnover was still slower, reaching approximately 22 weeks. In the normal subject on an average or high intake of sodium chloride, although the turnover is more rapid, approximately 13 per cent of the injected sodium 22 at the end of 14 weeks is still unaccounted for and is probably stored in bone. A basis for comparing values between pregnant patients is extremely difficult, and will probably have to be based upon the total body water in the lean body mass. The sodium space is increased in normal pregnancy and markedly increased in pre-eclamptic patients and to a lesser degree in the hypertensive disease group. This is true whether one calculates it as the total sodium space, as the milliliters per kilogram, per centimeter of height, or per square meter of body surface. The total exchangeable sodium is increased approximately 10 per cent in the normal pregnant patient and is markedly increased in the pre-eclamptic patient as evidenced by a 32 per cent drop by the eighth postpartum day. The hypertensive disease group is characterized by a larger amount of total exchangeable sodium but if calculated on a per kilogram basis then the values are less than normal, indicating that fat does not contain as much water and electrolyte as does the lean body tissue.

Serial studies of the cephalin flocculation and thymol turbidity tests in pregnant patients

Abstract This report does not imply that the liver may not be concerned in preeclampsia-eclampsia, because it undoubtedly is. It does indicate that the cephalin flocculation and thymol turbidity tests were within the normal range for the majority of patients who showed clinical evidence of pre-eclampsia with only two exceptions in which cases both tests were abnormal.