Effects of pregnancy, postpartum lactation, and oral contraceptive use on the lipoprotein cholesterol/triglyceride ratio

Lipoprotein cholesterol/triglyceride ratio changes have been observed previously with sex hormone use. To determine if the lipoprotein cholesterol/triglyceride ratio is similarly changed by pregnancy and postpartum lactation, we examined pregnant subjects at 36 weeks gestation and the same women at 6 weeks postpartum and compared them to age-matched, nonpregnant women using or not using oral contraceptives. The cholesterol/triglyceride ratios were examined as means and medians and as curvilinear functions of increasing triglyceride concentration. Median ratios did not predict all ratio changes identified graphically. At very-low-density lipoprotein (VLDL) triglyceride concentrations below 40 mg/dL, the VLDL ratio is less than control in oral contraceptive users and further reduced in pregnant women. Above triglyceride concentrations of 40-60 mg/dL, the curves in the three groups are indistinguishable. No effect of lactation is observed. The low-density lipoprotein (LDL) cholesterol/triglyceride ratio is comparably lower in pregnant subjects and oral contraceptive users at all concentrations of lipoprotein triglyceride and again there is no effect of lactation. In high-density lipoprotein (HDL), there is no effect of either pregnancy or oral contraceptive use on the cholesterol/triglyceride ratio, while it is significantly higher with lactation. Postpartum decreases in the VLDL and LDL cholesterol/triglyceride ratio are seen at all lipoprotein concentrations independent of lactation. We conclude that triglyceride enriches VLDL at low concentrations and LDL at all concentrations in pregnancy and with oral contraceptive use, suggesting a common, hormonal mechanism. HDL is enriched with cholesterol during postpartum lactation, consistent with decreased transfer of cholesterol to other lipoproteins.(ABSTRACT TRUNCATED AT 250 WORDS)     

U wave alternans: an electrocardiographic sign of left ventricular failure

All postextrasystolic complexes seen over a twelve year period were carefully analyzed. Normally only the first complex is different, showing a slightly altered T and a larger U wave. Ten patients with left ventricular failure and postextrasystolic pulsus alternans consistently showed postextrasystolic U wave alternans. Besides introducing an electrocardiographic sign of heart failure, this provides some insight into the underlying etiology of the U wave.     

Quantitation of apolipoprotein A-I of human plasma high density lipoprotein.

High density lipoproteins (HDL) may be controlled via their major apolipoprotein, A-I. To study this apolipoprotein, a simple, precise, and accurate immunodiffusion assay for A-I was developed and applied in a sample of Bell Telephone Company employees. A-I showed a slight increase with age in men (r=0.11, n=263) and women (r=0.15, n=257). A-I correlated closely with HDL cholesterol (r=0.72). It was weakly related to total triglyceride in women (r=0.24) but was inversely related in men (r=-0.17). Women on estrogen had the highest A-I levels (149 mg/dl +/- 26, x +/- S.D., n=29, p is less than 0.05), followed by women on combination oral contraceptives (141 +/- 26, n=80) whereas women on no medication had lower levels (129 +/- 25, n=99, p is less than 0.01) but men had the lowest levels (120 +/- 20, p is less than 0.01) In a separate group of 14 women given estrogen for 2 wks (1 mug/kg/day), A-I increased by 24%. Thus A-I is increased by exogenous and, most likely, endogenous estrogen, Among hyperlipidemic referral subjects, those with hypercholesterolemia (n=43) and hypertriglyceridemic women (n=33) had normal A-I levels. Among hypertriglyceridemic men both A-I and HDL cholesterol values were decreased (115 +/- 20, p is less than 0.01 and 37 +/- 3, p is less than 0.01, respectively, n=68) but were significantly lower among a group of myocardial infarction survivors (107 +/- 16, p is less than 0.01, and 27 +/- 6, p is less than 0.01, respectively, n=24). High density lipoprotein levels and the content of cholesterol in HDL associated with A-I appear to be decreased in coronary heart disease.     

Early surgical excision versus conventional therapy in patients with 20 to 40 percent burns: A comparative study

Using the records of 72 patients treated at the University of Washington Burn Center, this study compared the results of early surgical excision (by 14 days postburn) and autografting to those of autografting after spontaneous separation and bedside debridement of burn eschar. Excised patients had shorter hospitalizations and lower rates of burn wound sepsis and serious burn wound contamination, and less use of potentially toxic antibiotics (p < 0.05) than did the prognostically equivalent group treated before the introduction of early excision. Excised patients required more blood transfusions (p < 0.05), but did not differ significantly from controls in rates of mortality or other inpatient complications, in the number of operations performed, or in the adjusted hospital costs. Evaluation of patients treated over the entire study period for more shallow burns indicated no concurrent change in other aspects of burn care which might account for the observed results. We conclude that early excision and grafting in young, otherwise healthy patients with 20 to 40 percent total body surface area burns that are not likely to heal within 3 weeks is more effective than the more traditional management of slow wound separation and debridement.     

Lipid metabolism in pregnancy. II. Postheparin lipolytic activity and hypertriglyceridemia in the pregnant rat

Plasma postheparin lipolytic activity (PHLA) has been measured in rat pregnancy to qualitatively assess mechanisms of triglyceride removal from the circulation. This assessment can be made if the larger plasma volume of pregnancy is considered. A supramaximal dose of heparin avoids dilution of the heparin stimulus to PHLA release. Dilution of the released PHLA is corrected using measurements of plasma volume. In addition, no evidence of circulating inhibitors is present, and timing of PHLA appearance is unaffected by pregnancy. Prior studies of postheparin lipolytic activity in human pregnancy have not taken the effect of plasma volume into account and must therefore be reconsidered in light of the present results. We observed a biphasic in PHLA over the course of gestation. Levels were increased in midgestation (day 12), declined to normal by day 19, and fell rapidly to one-half of control by day 21. Assuming a functional role for the triglyceride lipases represented in PHLA, the data suggest the following hypothesis: triglyceride removal is increased or normal for the greater part of gestation and is decreased only at term. If this hypothesis proves true, the hypertriglyceridemia of pregnancy should be due largely to overproduction, with decreased removal contributing only near term.     

Broad-beta disease versus endogenous hypertriglyceridemia: levels and lipid composition of chylomicrons and very low density lipoproteins during fat-free feeding and alimentary lipemia.

To assess the roles of endogenous and exogenous lipid in the production of the abnormal lipoprotein patterns characteristic of broad-beta desease (with a type IVIII lipoprotein pattern) and endogenous hypertriglyceridemia (with a type IV pattern), oral fat loads (50 g/M-2) were administered to six subjects with broad-beta disease and to eight with endogenous hypertriglyceridemia following at leat 72 hr of 0% fat, 85% carbohydrate isocaloric formula feeding. Total plasma and Sf greater than 400, 100-400, 60-100, 30-60, and 20-30 lipoprotein cholesterol, triglyceride, and phospholipid levels were measured at 0 hr, 6 hr (at or before the peak of alimentary lipemia), and 24 hr following the fat load. Following fat-free feeding the levels and composition of the endogenous Sf greater than 400 lipoproteins were similar in both disorders; whereas total Sf20-400, and most notably, Sf 30-60 and 20-30 levels were increased and enriched in cholesterol in the subjects with broad-beta disease.     

Percutaneous drainage of abscesses in the postoperative abdomen that is difficult to explore

We have evaluated our experience with computerized tomography and ultrasonography guided percutaneous drainage of extrahepatic abdominal fluid collections in a group of 22 patients. The most common goal was to avoid or delay surgery on abdomens in which reoperation would be difficult, mainly in high-risk patients. Drainage of pancreatic fluid collections or abscesses was also attempted in a small number of the patients. Percutaneous drainage was curative in 69 percent of those with nonpancreatic abscesses but in only 33 percent of those with abscesses associated with the pancreas. There were no complications attributable to the procedure or to delays in subsequent surgical drainage. Two patients died from problems not directly related to the use of percutaneous drainage. Percutaneous catheter drainage of nonpancreatic abdominal abscesses can play a useful role in patients who are carefully selected because they possess a complex abdominal anatomy distorted by previous surgery and infection or they are at high risk if surgical exploration is carried out.