Use of an anaesthesia workstation barrier device to decrease contamination in a simulated operating room.

BACKGROUND.: Strategies to achieve reductions in perioperative infections have focused on hand hygiene among anaesthestists but have been of limited efficacy. We performed a study in a simulated operating room to determine whether a barrier covering the anaesthesia workstation during induction and intubation might reduce the risk of contamination of the area and possibly, by extension, the patient. METHODS.: Forty-two attending and resident anaesthetists unaware of the study design were enrolled in individual simulation sessions in which they were asked to induce and intubate a human simulator that had been prepared with fluorescent marker in its oropharynx as a marker of potentially pathogenic bacteria. Twenty-one participants were assigned to a control group, whereas the other 21 performed the simulation with a barrier device covering the anaesthesia workstation. After the simulation, an investigator examined 14 target sites with an ultraviolet light to assess spread of the fluorescent marker of contamination to those sites. RESULTS.: The difference in rates of contamination between the control group and the barrier group was highly significant, with 44.8% (2.5%) of sites contaminated in the control group vs 19.4% (2.6%) of sites in the barrier group ( P <0.001). Several key clinical sites showed significant differences in addition to this overall decrement. CONCLUSIONS.: The results of this study suggest that application of a barrier device to the anaesthesia workstation during induction and intubation might reduce contamination of the intraoperative environment.

A genome-wide scan for human obesity genes reveals a major susceptibility locus on chromosome 10.

Obesity, a common multifactorial disorder, is a major risk factor for type 2 diabetes, hypertension and coronary heart disease (CHD). According to the definition of the World Health Organization (WHO), approximately 6-10% of the population in Westernized countries are considered obese. Epidemiological studies have shown that 30-70% of the variation in body weight may be attributable to genetic factors. To date, two genome-wide scans using different obesity-related quantitative traits have provided candidate regions for obesity. We have undertaken a genome-wide scan in affected sibpairs to identify chromosomal regions linked to obesity in a collection of French families. Model-free multipoint linkage analyses revealed evidence for linkage to a region on chromosome 10p (MLS=4.85). Two further loci on chromosomes 5cen-q and 2p showed suggestive evidence for linkage of serum leptin levels in a genome-wide context. The peak on chromosome 2 coincided with the region containing the gene (POMC) encoding pro-opiomelanocortin, a locus previously linked to leptin levels and fat mass in a Mexican-American population and shown to be mutated in obese humans. Our results suggest that there is a major gene on chromosome 10p implicated in the development of human obesity, and the existence of two further loci influencing leptin levels.

Is postconditioning effective in prevention against long-lasting myocardial ischemia in the rabbit?

The goal of the study was to determine whether postconditioning protects against different ischemia durations in the rabbit. Rabbits were assigned to a 20-, 25-, 45- or 60-min coronary occlusion followed by 24-h of reperfusion. Rabbits received no further intervention (control) or were postconditioned with four cycles of 30-s occlusion and 30-s reperfusion after myocardial infarction. Plasma levels of troponin I were quantified throughout reperfusion. In control conditions, infarct sizes (% area at risk using triphenyltetrazolium chloride) after 20, 25, 45 and 60 min of coronary occlusions were 23+/-3, 51+/-4, 70+/-3 and 81+/-3 %, respectively. With 20 and 25 min occlusion, postconditioning reduced infarct size by 43+/-10 and 73+/-21 %, respectively. On the other hand, with 45 or 60 min occlusion, postconditioning had no significant effects on infarct size (61+/-3 and 80+/-2 % of area at risk). Preconditioning protocol was performed with 25- and 60-min coronary occlusion. As expected, preconditioning significantly reduced infarct size. In conclusion, in the rabbit, the cardioprotection afforded by postconditioning is limited to less than 45 min coronary occlusion.

[Late mediastinal metastasis of Ewing's sarcoma of tibia]. / Métastase médiastinale tardive d'un sarcome d'Ewing du tibia.

Peripheral neuroectodermal tumors constitute a large spectrum of small round cell tumors among which Ewing's sarcoma is the most undifferentiated type. They are rare tumors which often concern young people and generally occur in bone tissue. Their metastatic potential is high, generally early, and rarely after five years. We report the case of a 45-year-old woman who presented a mediastinal metastasis eight years after the primitive tumor of tibia. The diagnosis was made on small core biopsies obtained by CT punction, and was based on morphologic analysis, immunohistochemistry, and confirmed by molecular biology. The presence of metastasis is the main prognostic factor. Despite therapeutic progress, the global survival rate of metastatic patients is still poor.

Melanocortin-4 receptor mutations are a frequent and heterogeneous cause of morbid obesity.

By integrating an agonist satiety signal, provided by alpha-melanocyte-stimulating hormone (alpha-MSH), and an antagonist signal, provided by agouti-related protein (AGRP), the melanocortin-4 receptor (MC4-R) is a key element in the hypothalamic control of food intake. Inactivation of the gene encoding this G protein-coupled receptor causes obesity in mice. In humans, frameshift mutations in MC4-R cause an early-onset dominant form of obesity in two families. In this study we find a high frequency (4%) of rare heterozygous MC4-R mutations in a large population of morbidly obese patients. No such mutations were found in controls. By analyzing the phenotypes of the probands carrying these mutations, we demonstrate that these patients display a common, nonsyndromic form of obesity. Interestingly, functional analysis of the mutant receptors indicates that obesity-associated defects in MC4-R range from loss of function to constitutive activation. Transmission of these mutations in the families of the carriers indicates a variable expressivity that is not related to the functional severity of the mutations. This variable expressivity of MC4-R-associated obesity is not due to variations in genes for alpha-MSH or AGRP. Taken together, these results demonstrate that MC4-R mutations are a frequent but heterogeneous genetic cause of morbid obesity.

Resuscitation thoracotomy.

Resuscitation thoracotomy is a rarely performed procedure whose use, in France, remains marginal. It has five specific goals that correspond point-by-point to the causes of traumatic cardiac arrest: decompression of pericardial tamponade, control of cardiac hemorrhage, performance of internal cardiac massage, cross-clamping of the descending thoracic aorta, and control of lung injuries and other intra-thoracic hemorrhage. This approach is part of an overall Damage Control strategy, with a targeted operating time of less than 60minutes. It is indicated for patients with cardiac arrest after penetrating thoracic trauma if the duration of cardio-pulmonary ressuscitation (CPR) is <15minutes, or <10minutes in case of closed trauma, and for patients with refractory shock with systolic blood pressure <65mm Hg. The overall survival rate is 12% with a 12% incidence of neurological sequelae. Survival in case of penetrating trauma is 10%, but as high as 20% in case of stab wounds, and only 6% in case of closed trauma. As long as the above-mentioned indications are observed, resuscitation thoracotomy is fully justified in the event of an afflux of injured victims of terrorist attacks.

F16357, a novel protease-activated receptor 1 antagonist, improves urodynamic parameters in a rat model of interstitial cystitis.

BACKGROUND AND PURPOSE: The aims of the present study were to characterize the role of PAR1 in rat bladder under inflammatory conditions and determine whether a selective PAR1 antagonist, F16357, can prevent the pathophysiological symptoms of cyclophosphamide-induced interstitial cystitis (IC). EXPERIMENTAL APPROACH: Immunohistochemistry, contractile activity in isolated bladder and urodynamics were determined before and after cyclophosphamide treatment. F16357 was administered intravesically during the acute phase of inflammation, and effects on PAR1 and PAR1-related bladder contraction evaluated 24 h after cyclophosphamide injection. Urodynamics and associated voided volumes were recorded 7 and 24 h after cyclophosphamide. KEY RESULTS: In control conditions, PAR1 was present only in some umbrella cells. Cyclophosphamide disrupted the urothelium and expression of PAR1 by all remaining urothelial cells. After F16357 treatment, urothelial damage was absent and PAR1 immunoreactivity similar to control tissues. Thrombin and TFLLR-NH2 induced bladder contractions. These were increased in inflammatory conditions and antagonized by F16357 in a concentration-dependent manner. In telemetric experiments, furosemide increased urine production and voiding frequency for 60 min, 7 h after cyclophosphamide injection. Intravesical administration of F16357 blocked these changes with a return to a physiological profile; 24 h after cyclophosphamide, the volume of micturition was still lower with no increase in number of micturitions. F16357 30 µM reduced the number of micturitions and improved bladder capacity, but did not affect diuresis. Under similar experimental conditions, lidocaine 2% induced comparable effects. CONCLUSIONS AND IMPLICATIONS: PAR1 is expressed in rat bladder, overactivated in inflammatory conditions and involved in bladder function and sensation. F16357 could represent an interesting candidate for IC treatment.

A sib-pair analysis study of 15 candidate genes in French families with morbid obesity: indication for linkage with islet 1 locus on chromosome 5q.

As part of an ongoing search for susceptibility genes in obese families, we performed linkage analyses in 101 French families between qualitative and quantitative traits related to morbid obesity and polymorphisms located in or near 15 candidate genes whose products are involved in body weight regulation. These included cholecystokinin A and B receptors (CCK-AR and CCK-BR), glucagon-like peptide 1 receptor (GLP-1R), the LIM/homeodomain islet-1 gene (Isl-1), the caudal-type homeodomain 3 (CDX-3), the uncoupling protein 1 (UCP-1), the beta3-adrenoceptor (beta3-AR), the fatty acid-binding protein 2 (FABP-2), the hormone-sensitive lipase (HSL), the lipoprotein lipase (LPL), the apoprotein-C2 (apo-C2), the insulin receptor substrate-1 (IRS-1), the peroxisome proliferator-activated receptor-gamma (PPAR-gamma), tumor necrosis factor-alpha (TNF-alpha), and the liver carnitine palmitoyltransferase-1 (CPT-1). Phenotypes related to obesity such as BMI, adult life body weight gain, fasting leptin, insulin, fasting glycerol, and free fatty acids were used for nonparametric sib-pair analyses. A weak indication for linkage was obtained between the Isl-1 locus and obesity status defined by a z score over one SD of BMI (n = 226 sib pairs, pi = 0.54 +/- 0.02, P = 0.03). Moreover, a suggestive indication for linkage was found between the Isl-1 locus and BMI and leptin values (P = 0.001 and 0.0003, respectively) and leptin adjusted for BMI (P = 0.0001). Multipoint analyses for leptin trait with Isl-1 and two flanking markers (D5S418 and D5S407) showed that the logarithm of odds (LOD) score is 1.73, coinciding with the Isl-1 locus. Although marginally positive indications for linkage in subgroups of families were found with IRS-1, CPT-1, and HSL loci, our data suggested that these genes are not major contributors to obesity. Whether an obesity susceptibility gene (Isl-1 itself or another nearby gene) lies on chromosome 5q should be determined by further analyses.

Soluble leptin receptor in serum of subjects with complete resistance to leptin: relation to fat mass.

Leptin resistance and obesity have been related to mutations of the leptin receptor gene in rodents and, recently, in a consanguineous family. The latter mutation results in a receptor lacking transmembrane and intracellular domains. Homozygous and heterozygous individuals with this mutation had serum leptin levels higher than expected, given their BMIs: 600, 670, and 526 ng/ml and 145, 362, 294, 240, and 212 ng/ml, respectively. Their serum leptin was fractionated by gel filtration: >80% was present as a high-molecular size complex vs. 7.5% in the nonmutated sister. Western blot analysis showed a band at 146 kDa reacting specifically with an antibody directed against the leptin receptor ectodomain. In 10 obese control subjects, as in the mutated patients, free leptin levels correlated with BMI (r = 0.70, P = 0.0011) and reflected fat mass, regardless of leptin receptor functioning. In the patients, bound leptin levels correlated with BMI (r = 0.99, P = 0.0002) and were related to the number of mutated alleles. These data demonstrate that the truncated receptor is secreted into blood and binds the majority of serum leptin, markedly increasing bound and total leptin. Free serum leptin was similarly correlated with BMI in the mutated and nonmutated obese individuals, providing evidence that the relationship between BMI and circulating free leptin is preserved in this family. This finding suggests that the leptin receptor itself may not be specifically involved in the control of leptin secretion, and it supports the concept of relative resistance to leptin in common obesity.

Indication for linkage of the human OB gene region with extreme obesity.

Obesity is one of the most significant risk factors for hypertension, coronary heart disease, and NIDDM (Frayn KN, Coppack SW: Insulin resistance, adipose tissue and coronary heart disease. Clin Sci 82:1-8, 1992; Kaplan NM: The deadly quartet: upper-body obesity, glucose intolerance, hypertriglyceridemia, and hypertension. Arch Intern Med 149:1514-1520, 1989). While family segregation, adoption, and twin studies have indicated that degree of adiposity has a significant genetic component (Stunkard AJ, Harris JR, Pedersen NL, McClearn GE: The body-mass index of twins who have been reared apart. N Engl J Med 322:1483-1487, 1990; Bouchard C, Despres J-P, Mauriege P: Genetic and nongenetic determinants of regional fat distribution. Endocr Rev 14:72-93, 1993), the genes and predisposing mutations remain poorly understood. This is in contrast to several well-defined genetic models for obesity in rodents, particularly the mouse obese (ob) gene, in which loss-of-function mutations cause severe obesity. Recent studies have demonstrated a substantial reduction in body fat when recombinant ob protein (leptin) is administered to mice. To test the relevance of these observations to human obesity, the location of the human homologue (OB) was established by radiation hybrid mapping and eight microsatellite markers spanning the OB gene region (7q3l.3) were genotyped in 101 obese French families. Affected-sib-pair analyses for extreme obesity, defined by BMI >35 kg/m2, revealed suggestive evidence for linkage to three markers located within 2 cM of the OB gene (D7S514, D7S680, and D7S530). The OB gene is therefore a candidate for genetic predisposition to extreme obesity in a subset of these families.

Genetic studies of the sulfonylurea receptor gene locus in NIDDM and in morbid obesity among French Caucasians.

The sulfonylurea receptor (SUR) is a key component in glucose-stimulated insulin secretion. Obesity and NIDDM are frequently associated and share some metabolic abnormalities, suggesting that they might also share some susceptibility genes. Thus, the SUR encoding gene is a plausible candidate for a primary pancreatic beta-cell defect and thus for hyperglycemia and weight gain. Through association and linkage studies, we have investigated the potential role of the SUR gene in families with NIDDM and in two independent sets of morbidly obese families. The exon 22 T-allele at codon 761 was more common in patients with NIDDM (7.7%) and morbid obesity (7.8%) than in control subjects (1.8%, P = 0.030 and P = 0.023, respectively). This variant was associated with morbid obesity (odds ratio 3.71, P = 0.017) and NIDDM (odds ratio 2.20, P = 0.04; association dependent on BMI). Although the frequencies for intron 24 variant were similar in all groups, morbidly obese patients homozygous for the c-allele had a more deleterious form of obesity. Sib-pair linkage studies with NIDDM in French Caucasian families gave no evidence for linkage to the SUR locus. However, in one set of the obese families, we found an indication for linkage with a SUR-linked microsatellite marker (D11S419, P = 0.0032). We conclude that in Caucasians, the SUR locus may contribute to the genetic susceptibility to NIDDM and obesity.

Recommendations regarding obesity surgery.

In France, 1,000 obese persons per month undergo a bariatric operation. Obesity surgery requires coordination and monitoring of aftercare. The French public health-care insurer asked the medical associations involved in obesity management to provide guidelines for obesity surgery. The recommendations were developed by the national associations of Obesity, Nutrition and Diabetes: the Association Française d'Etudes et de Recherches sur l'Obésité (AFERO), member of the EASO and IASO; the Association de Langue Française pour l'Etude du Diabète et des Maladies Métaboliques (ALFEDIAM); the Société Française de Nutrition (SFN); and the Société Française de Chirurgie de l'Obésité (SOFCO). This article presents the short version of the guidelines.

Increased resistance to ischaemic injury in the isolated perfused atherosclerotic heart of the cholesterol-fed rabbit.

OBJECTIVE: In isolated, Langendorff-perfused hearts in the early stages of atherosclerosis from rabbits exposed to hypercholesterolaemia induced by 2% cholesterol feeding for 6 weeks (n = 23), and age-matched normal controls fed standard chow (n = 12), we studied baseline cardiac haemodynamics and the susceptibility of these hearts to 30 min global, normothermic ischaemia and 90 min reperfusion. METHODS: Spontaneously beating hearts were perfused with oxygenated Krebs buffer (pH 7.4) at constant pressure, and were enclosed in a thermostated water jacket at 37 degrees C. Isovolumetric left ventricular (LV) pressure was measured by means of a balloon placed in the LV cavity. An electromagnetic flow probe placed around the perfusion cannula determined coronary flow. At the end of an initial 30 min stabilisation period, several baseline cardiodynamic variables were measured, just before subjecting the hearts to 30 min ischaemia. Recovery of mechanical function and lactate dehydrogenase (LDH) and creatine phosphokinase (CPK) activities in the coronary effluent were recorded throughout 90 min reperfusion. RESULTS: Baseline spontaneous heart rate, LV developed pressure (LVDP), coronary flow and pressure-rate index (PRI) were all significantly lower in hearts from cholesterol-fed rabbits (CFR) than in age-matched controls (P < 0.01). Although large differences in several baseline haemodynamic parameters in hearts from CFR and controls were evident before ischaemia, no statistically significant differences were discernible in these parameters between the two groups from 60 min reperfusion onwards (p = NS). Furthermore, CPK and, to a lesser extent, LDH release during reperfusion was attenuated in hearts from CFR compared to controls. CONCLUSIONS: Hearts from CFR exhibited markedly improved recovery upon reperfusion compared to age-matched controls, strongly suggesting increased myocardial resistance to ischaemic injury.

Depressed transient outward and calcium currents in dilated human atria.

OBJECTIVE: The aim was to compare action potentials and ionic currents (steady state current, calcium current, calcium independent transient outward current) in two groups of trabeculae and myocytes, isolated from either dilated or non-dilated human atria. METHODS: Specimens of right atrial appendage were obtained from two groups of adult patients at the time of open heart surgery, a group with non-dilated atria and a group in which right atria were clearly dilated. Action potentials were recorded with standard microelectrodes from isolated superfused trabeculae. Action potentials and ionic currents were recorded from single myocytes using the patch clamp technique in the whole cell configuration in current clamp and voltage clamp modes respectively. RESULTS: In trabeculae taken from dilated atria the action potential was shortened and the plateau was markedly depressed compared to trabeculae taken from non-dilated atria. Similar results were obtained with single myocytes isolated from non-dilated and dilated atria. The density of the steady state current measured at the end of 0.75 s or 1 s pulses was not statistically different in the two groups of cells in the whole range of negative potentials, whereas at strongly positive potentials (> +40 mV) it was significantly reduced in cells from dilated atria compared to cells from non-dilated atria. The density of the total peak outward current was significantly reduced in cells from dilated atria [13.46(SEM 2.7) pA.pF-1 at +70 mV, n = 18] compared to cells from non-dilated atria [33.12(6.2) pA.pF-1, n = 20, p < 0.001]. The transient component of outward current was strongly depressed (at +20 mV and more positive potentials) in cells from dilated atria. The calcium current density was still more severely depressed than the total outward current in cells from dilated atria [4.46(1.06) pA.pF-1 at +20 mV, n = 26] compared to cells from non-dilated atria [17.43(1.98) pA.pF-1, n = 38, p << 0.001]. Kinetic parameters of both calcium and transient outward currents remained similar in cells from the two groups. CONCLUSIONS: The observation that in cells from dilated human atria the calcium current is more severely depressed than the total outward current can help to explain why in dilated human atria the action potential plateau is shorter and of lower amplitude than in non-dilated atria.

Cellular electrophysiological effects of flecainide on human atrial fibres.

STUDY OBJECTIVE: The aim of the study was to examine the electrophysiological characteristics of human atrial specimens collected during heart surgery and to investigate the effects of the class I antiarrhythmic agent flecainide on their electrical activity. DESIGN: Atrial specimens were studied using standard microelectrode techniques, with and without superfused flecainide (5 x 10(-7) M) or the transient outward current inhibitor 4-aminopyridine (0.5 mM). EXPERIMENTAL MATERIAL: Atrial fragments 0.5-1.0 cm2 were obtained at operation from 34 patients, mean age 30 years. There was no history of previous atrial arrhythmia in any patient and drug therapy was stopped 24 h before surgery. MEASUREMENTS AND MAIN RESULTS: Two types of transmembrane action potential were identified: (1) triangular shaped potentials (group A, classically found in animal models); (2) potentials with a large plateau preceded by a notch (group B). The effect of flecainide was compared on the the two types of action potential. In both, flecainide lessened the depolarisation rate. In group B, but not in group A, it increased the action potential duration at 50% and 90% repolarisation (APD50, APD90) and the effective refractory period. The notch in group B action potentials is generated by transient outward currents (Ito). Inhibition of these currents, either by increasing the pacing rate or by adding 4-aminopyridine, limited the increase in APD50, APD90, and effective refractory period generated by the presence of flecainide. CONCLUSIONS: The effects of flecainide on the atrial repolarisation process depend on the shape of the action potential. These effects are more marked in cells with a plateau, where Ito is activated.

Chewing and swallowing as indices of the stimulation to eat during meals in humans: effects revealed by the edogram method and video recordings.

Patterns of chewing and swallowing were recorded during standardized meals in humans. Cocktail size (3 cm2) open sandwiches were served in one of five different flavors. An oscillographic recording of chewing and swallowing showed that chewing activity varied with the palatability and variety of foods. Chewing time was shorter and fewer chews were observed as palatability increased. Swallowing did not change as a function of stimulus flavor. Pause duration between two successive food pieces became shorter as palatability increased. The effects of sensory factors were most evident at the beginning of meals and decreased until the end of meals. A later study which compared eating parameters in sandwich, semi-solid, and traditional French meals (different courses ingested in succession: appetizer, main course, cheese and dessert), as assessed from video recordings, found that different microstructure parameters responded to palatability manipulation in different meal types. Strength of mastication and prandial drinking might be other important parameters to look at in order to understand the motivation to eat and its fluctuations during the meal.

Relationship between thyrotropin and thyroxine changes during recovery from severe hypothyroxinemia of critical illness.

In a prospective study of critically ill hypothyroxinemic we assessed the relationship between serum TSH and T4 during the return of serum T4 to normal during recovery. In this longitudinal study of 60 patients with a variety of critical illnesses, including burns, septicemia, and acute renal failure, serum T4 fell to less than 2.7 micrograms/dl (35 nmol/liter) in 24 patients, of whom 14 survived with return of T4 to normal. A rise in total T4 of more than 1.9 microgram/dl (25 nmol/liter) within 96 h occurred 13 times in 10 patients, while 4 patients had slower increases in T4. All 13 episodes of rapid T4 rise [1.7 +/- 0.8 (+/- SD) to 5.6 +/- 2.1 micrograms/dl] were associated with a marked increase in serum TSH (1.1 +/- 0.8 to 7.0 +/- 5.2 mU/liter), and TSH was transiently above normal during 8 episodes of T4 recovery. In the 6 episodes with sampling less than 6 h apart, the TSH rise consistently preceded the T4 rise. In the 4 patients who received dopamine, TSH and T4 remained low until cessation of therapy. During the TSH rise, only minor changes, which could not account for the increase in total T4, occurred in T4-binding globulin (12.9 +/- 3.3 to 14.8 +/- 3.3 mg/liter), prealbumin (208 +/- 73 to 234 +/- 82 mg/liter), and albumin (28.3 +/- 2.9 to 31.9 +/- 2.9 g/liter). Mean free T4 increased (0.60 +/- 0.34 to 1.45 +/- 0.56 ng/dl), as did total T3 (16 +/- 14 to 76 +/- 44 ng/dl), during the phase of TSH rise, suggesting that the increase in TSH was not simply a consequence of diminished negative feedback due to increased plasma binding. The very close and consistent temporal relationship between TSH and T4 during the recovery phase suggests that TSH may have an essential role in the return of T4 to normal during recovery from critical nonthyroidal illness.

Contraception in hypertensive women using a vaginal ring delivering estradiol and levonorgestrel.

Contraception with a vaginal ring (CVR) that delivers estradiol and levonorgestrel was used during a mean of 15.6 menstrual cycles in 12 hypertensive women. Blood pressure (BP) was measured 5 times on each visit during 2 pretreatment control cycles; during the 1st, 2nd, 4th, 6th, and from the 9th to 12th cycles of CVR use; and again after a 1-month recovery period. No significant change in BP occurred during CVR use in any of the subjects. Plasma renin substrate and antithrombin III activity did not vary significantly, which suggests the utility of administering natural estradiol via the vagina, thus avoiding the first pass effect that occurs with oral contraceptives. Significant decreases in plasma sex hormone-binding globulin, cholesterol, high density lipoprotein cholesterol, phospholipids, and triglycerides occurred, indicating an androgenic effect of levonorgestrel. We conclude that the CVR is a method of contraception that does not elevate BP in hypertensive women.

PIP: Contraception with a vaginal ring (CVR) that delivers estradiol and levonorgestrel was used during a mean of 15.6 menstrual cycles in 12 hypertensive women. Blood pressure (BP) was measured 5 times on each visit during 2 pretreatment control cycles; during the 1st, 2nd, 4th, 6th, and from cycles 9-12 of CVR use; and again after a 1-month recovery period. No significant change in BP occurred during CVR use in any of the subjects. Plasma renin substrate and antithrombin III activity did not vary significantly, which suggests the utility of administering natural estradiol via the vagina, thus avoiding the 1st pass effect that occurs with oral contraceptives. Significant decreases in plasma sex hormone-binding globulin, cholesterol, high density lipoprotein cholesterol, phospholipids, and triglycerides occurred, indicating an androgenic effect of levonorgestrel. The authors conclude that the CVR is a method of contraception which does not elevate BP in hypertensive women.

Biological effects of estradiol-17 beta in postmenopausal women: oral versus percutaneous administration.

To determine whether the route of administration or the type of estrogen used in estrogen replacement therapy (ERT) is more important in avoiding effects on hepatic function, 24 postmenopausal women were studied before and at the end of 2 months of oral or percutaneous administration of the same estrogen, estradiol-17 beta (E2). The treatments studied were oral micronized E2, 2 mg/day (9 women); oral E2 valerate, 2 mg/day (5 women), and percutaneous E2, 3 mg/day (10 women). Specific plasma biological and biochemical markers of estrogenic action were evaluated, namely, E2, estrone (E1), LH, FSH, sex steroid binding protein (SBP), renin substrate, antithrombin activity, and lipoproteins (high density lipoprotein cholesterol, low density lipoprotein cholesterol, very low density lipoprotein triglycerides). Both oral and percutaneous administration of E2 increased plasma E2 levels up to midfollicular values and decreased LH and FSH levels into the same range. Oral administration of E2 led to substantial increases in plasma E1, SBP, renin substrate, and VLDL levels, whereas AT decreased significantly. Percutaneous administration of E2 led to a physiological plasma E1/E2 ratio and did not induce any change in hepatic proteins. These data suggest that the route of administration of E2 determines the biochemical response to ERT in postmenopausal women. SBP is the most sensitive marker of the liver action of estrogen, and triglycerides also are simple and useful markers for this effect. Percutaneous E2 therapy is an effective method of ERT, and has no measurable effects on hepatic markers of estrogen action.