Effect of epidural analgesia on operative vaginal birth rate.

The aim of the study was to investigate if epidural analgesia may affect the operative vaginal birth rate. An observational study was carried out on 1,158 in low-risk patients who delivered vaginally; 46.9% of these patients underwent epidural analgesia using different doses and drugs. Overall, epidural analgesia enhanced the probability of vacuum delivery (OR 2.70 95% CI 1.88-3.89, p < 0.001). Vacuum application was increased about seven times by administration of fentanyl alone at the first dose, while it was reduced if ropivacaine was added to fentanyl. In patients undergoing epidural analgesia, increasing the amount of ropivacaine at the first dose reduced the probability of vacuum delivery (OR 0.82; 95% CI 0.67-1.00, p = 0.05). Moreover, increasing the number of top-ups reduced the probability of vacuum delivery (OR 0.49 95% CI 0.27-0.93, p = 0.029) and the time of the second stage of labor. On the other hand, increasing time from the first dose of epidural to the last top-up increased the risk of operative vaginal delivery (OR 1.33 95% CI 1.03-1.72, p = 0.031) and the time of the second stage of labor. Epidural analgesia seems to favor spontaneous delivery when it is properly carried on.

Impact of the medicalization of labor on mode of delivery.

AIMS: To evaluate whether routine medical interventions during labor (oxytocin augmentation, induction, amniotomy, epidural analgesia) condition the outcome of delivery independently of each other and of obstetric risk (calculated in an objective manner). Moreover, to evaluate whether there is an ideal window for initiating such interventions. METHODS: Prospective, observational study with 1,047 patients enrolled. RESULTS: Medical interventions were high, whether in low-, medium- or high-risk pregnancies. Oxytocin augmentation (odds ratio 4.678) labour induction (odds ratio 1.717) amniotomy (odds ratio 1.403) and obstetric risk (intermediate-risk odds ratio 1.889, high-risk odds ratio 2.008) increase the probability of an operative delivery. Oxytocin augmentation increases both the probability of a Cesarean delivery and vacuum extraction. Epidural analgesia reduces the probability of cesarean delivery and increases the probability of vacuum extraction. The greater the cervical dilation when oxytocin infusion is initiated, the lower the probability of an operative delivery. The more advanced the cervical dilation and the lower the station when amniotomy or epidural analgesia are carried out, the lower the probability of an operative delivery. Obstetric risk and oxytocin augmentation appear to increase the probability of operative delivery in patients who have undergone amniotomy or epidural analgesia. In addition, labor induction in patients who undergo epidural analgesia increases the risk of operative delivery. CONCLUSIONS: Medical interventions during labor are high and cause a rise in operative delivery. Therefore, practitioners should defer it as much as possible. The exception is epidural analgesia because it seems to reduce the number of cesarean sections.

Intravaginal gemeprost and second-trimester pregnancy termination in the scarred uterus.

OBJECTIVE: To investigate the effectiveness and complication rate of intravaginal gemeprost, a prostaglandin E(1) analogue, for second-trimester pregnancy termination in women with a scarred uterus. METHODS: Of 439 women undergoing induced abortion between the 13th and the 23rd week of pregnancy, 67 had a scarred uterus because of 1 or more cesarean sections or myomectomy. All women received a 1 mg dose of gemeprost intravaginally every 3 h, up to 5 times over 24 h. Those who did not respond received further cycles of gemeprost treatment. RESULTS: The rate of successful abortions among women with uterine scars was not different from that observed in the nulliparous controls, but previously vaginal delivery was associated with a shorter induction to abortion interval. The rate of severe complications did not differ between the groups, and was about 1%. CONCLUSION: The rate of complications following intravaginal administration of a PGE(1) analogue for second-trimester pregnancy termination was similar in women with a scarred or unscarred uterus.

Adrenomedullin, a new vasoactive peptide, is increased in preeclampsia.

Adrenomedullin is a novel peptide that elicits a long-lasting vasorelaxant activity. Recently, we found high concentrations of adrenomedullin in maternal and umbilical cord plasma and in amniotic fluid in full-term human pregnancy, indicating a role of this peptide during gestation. To investigate the possibility that adrenomedullin is involved in the pathophysiology of preeclampsia, we measured its concentration in maternal and fetoplacental compartments. We studied 12 normotensive nonpregnant women, 13 hypertensive nonpregnant subjects, 29 patients with preeclampsia, and 30 normotensive pregnant women. In all patients, plasma was collected from the cubital vein, and amniotic fluid samples were obtained by transabdominal amniocentesis or at elective cesarean section. Plasma samples from umbilical vein and placental tissues were collected at delivery. Adrenomedullin was assayed on plasma and amniotic fluid samples using a specific radioimmunoassay, and its localization and distribution on placental sections was determined by immunohistochemistry. Adrenomedullin concentrations were higher in hypertensive than in normotensive nonpregnant patients. Pregnant women had higher adrenomedullin levels than nonpregnant subjects, although maternal plasma adrenomedullin concentrations did not differ between normal pregnant and preeclamptic women. Preeclamptic patients showed higher concentrations (P<0.01) than normotensive pregnant women of adrenomedullin in amniotic fluid (252+/-29 versus 112+/-10 fmol/ micromol creatinine) and umbilical vein plasma (18.1+/-2.1 versus 8. 5+/-1.1 fmol/mL). Increased local production of adrenomedullin is associated with preeclampsia. The fetus seems to be responsible for the higher levels of this hormone. Increased adrenomedullin concentrations may be necessary to maintain placental vascular resistance and/or fetal circulation at a physiological level.

Sympathetic modulation of radial artery compliance in congestive heart failure.

Animal studies have suggested that arterial compliance can be modulated by adrenergic influences. Whether this adrenergic modulation also occurs in humans is still a matter of debate. In the present article we address this issue by examining the relationships between sympathetic tone and arterial compliance in a variety of physiological and pathophysiological conditions. We have found that cigarette smoking, ie, an action that produces a marked sympathetic activation, causes a significant reduction in radial artery compliance, as measured by an echotracking device capable of providing continuous beat-to-beat evaluation of this hemodynamic variable. When expressed as compliance index, ie, as the ratio between the area under the compliance-pressure curve and pulse pressure, the reduction amounted to 35.7 +/- 4.8% (mean +/- SEM) and was independent of the smoking-related blood pressure increase. Furthermore, pharmacological stimulation of adrenergic receptors located in the arterial wall was also shown to affect arterial compliance because the radial artery compliance index was markedly reduced (- 29.5 +/- 3.9%) during phenylephrine infusion in the brachial artery at doses devoid of any systemic blood pressure effect. Evidence was also obtained that the relationship between sympathetic activation and arterial compliance has pathophysiological relevance, because in 17 patients with congestive heart failure (New York Heart Association classes II through IV) there was a significant inverse correlation (r = .62, P < .01) between muscle sympathetic nerve activity (directly measured by microneurography in the peroneal nerve) and radial artery compliance.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenomedullin production is increased in normal human pregnancy.

OBJECTIVE: Adrenomedullin, a recently discovered vasoactive peptide originally identified in pheochromocytoma, has been found to be increased in the plasma of pregnant women at term. This study was designed to elucidate whether adrenomedullin secretion is dependent on gestational age and the possible source and function of this peptide in human pregnancy. STUDY DESIGN: Adrenomedullin concentrations were determined by RIA in amniotic fluid and maternal plasma obtained from 110 pregnant women between 8 and 40 weeks of gestation. Subjects were stratified into five groups according to gestational age. In term patients (n = 15), adrenomedullin was also measured in the umbilical artery and vein separately. RESULTS: High concentrations of adrenomedullin were present in plasma and amniotic fluid samples from patients in the first, second and third trimester. There was no significant difference in mean maternal plasma concentration of adrenomedullin between the five patient groupings. Amniotic fluid adrenomedullin concentrations decreased from 81.2 +/- 11.7 pg/ml at 8-12 weeks of gestation to 63.7 +/- 6.0 pg/ml at 13-20 weeks of gestation and then increased at 21-28 weeks of gestation to 99.1 +/- 10.4 pg/ml. A further increase was found in samples collected after 37 weeks of gestation (132.6 +/- 10.1 pg/ml). In the umbilical vein, adrenomedullin concentration was higher (P < 0.05) than in the artery (65.7 +/- 6.1 pg/ml and 48.5 +/- 5.2 pg/ml respectively), suggesting that adrenomedullin in the fetal circulation derives from the placenta. CONCLUSIONS: Our results demonstrate the presence of adrenomedullin in maternal plasma and amniotic fluid throughout gestation, and show that its production starts very early in gestation, suggesting that this hormone may have an important role in human reproduction, from implantation to delivery.

Adrenomedullin, a new peptide, in patients with insulinoma.

BACKGROUND: It has been demonstrated that adrenomedullin, a newly discovered peptide, affects the release of insulin from pancreatic islets cells, suggesting a role in the insulin-regulating system. OBJECTIVE: To investigate whether adrenomedullin secretion is modified in patients with insulin-secreting islet cell tumours. DESIGN: The study was performed in nine patients with surgically treated insulinoma. Circulating adrenomedullin was assayed using a specific radioimmunoassay and its localization and distribution in the tumour were determined by means of immunohistochemistry. RESULTS: Adrenomedullin concentrations were significantly greater in patients with insulinoma (6.6 +/- 3.2 fmol/ml) than in controls (2.1 +/- 1.1 fmol/ml). In six patients monitored before and after surgery, plasma adrenomedullin decreased from 6.3 +/- 2.9 fmol/ml to 3.0 +/- 1.6 fmol/ml. Immunoreactive adrenomedullin was localized exclusively in the tumours cells, whereas stroma, surrounding pancreas parenchyma and major ducts were negative for the peptide. CONCLUSIONS: Our findings indicate that circulating adrenomedullin is increased in insulinoma and that this increase is related to the neoplastic phenotype.

Circulating adrenomedullin is increased in patients with corticotropin-dependent Cushing's syndrome due to pituitary adenoma.

It has been demonstrated that adrenomedullin, a newly discovered peptide with structural similarity to calcitonin gene-related peptide (CGRP), is expressed in pituitary gland and affects basal and corticotropin (ACTH)-releasing factor (CRF)-stimulated ACTH release in animals, thus suggesting its potential role in regulating the hypothalamus-pituitary-adrenal axis. To evaluate whether ACTH and cortisol levels affect adrenomedullin production in humans, we studied 14 patients with Cushing's syndrome due to pituitary adenoma and 8 patients with Cushing's syndrome due to adrenal tumor, with measurement of circulating adrenomedullin by a specific radioimmunoassay (RIA). Adrenomedullin concentrations were significantly higher in patients with pituitary adenoma (37.6 +/- 17.8 pg/mL) versus controls (13.7 +/- 6.1 pg/mL) and patients with adrenal adenoma (17.8 +/- 2.2 pg/mL). After pituitary surgical treatment, plasma adrenomedullin decreased significantly. In one patient with Cushing's syndrome due to pituitary adenoma who underwent simultaneous sampling of the inferior petrosal venous sinuses, the adrenomedullin concentration was significantly higher in plasma collected from the side with the adenoma and increased after CRF administration (delta increase, 42.6%), according to ACTH levels. Our findings indicate that circulating adrenomedullin is increased in Cushing's disease, and the pituitary gland may represent the site of the elevated production of adrenomedullin in this condition.

Amniotic fluid concentrations of adrenomedullin in preterm labor.

OBJECTIVE: To determine whether adrenomedullin levels in amniotic fluid were associated with preterm labor. METHODS: We measured immunoreactive adrenomedullin in amniotic fluid collected by amniocentesis from 36 women with clinical diagnosis of preterm labor or preterm premature rupture of membranes (PROM) and from 18 normal pregnant women. RESULTS: Amniotic fluid from cases of PROM and failure to respond to tocolysis were associated significantly with higher amniotic fluid adrenomedullin concentrations (177.0 +/- 22.5 pg/mL and 182.7 +/- 22.0 pg/mL, respectively, P < .01) than that from uncomplicated pregnancies (101.2 +/- 28.1 pg/mL) or preterm labor responsive to tocolysis (102.3 +/- 26.8 pg/mL). CONCLUSION: Amniotic fluid adrenomedullin is higher than normal in cases of PROM and preterm labor unresponsive to tocolysis, perhaps indicating enhanced synthesis from placenta or fetal membranes being stimulated by bacterial products.

Changes in plasma adrenomedullin levels during the menstrual cycle.

We investigated whether the levels of adrenomedullin, a novel peptide produced by several tissues, including the pituitary gland, change during the ovarian cycle. We studied 13 healthy women with regular menstrual cycles. Plasma samples were collected at 7, 14, 21 and 28 days of the ovarian cycle and assayed for adrenomedullin 1-52 using a specific RIA. LH, FSH, 17beta-estradiol, and progesterone concentrations were also determined. The adrenomedullin profile during ovarian cycle was similar to that of LH; plasma adrenomedullin increased from 10.9 pg/ml at the 7th day to 15.1 pg/ml at the 14th, and decreased to 8.5 pg/ml in the subsequent menses. The changes in plasma adrenomedullin were related to changes in LH and 17beta-estradiol. The cause of the increase in adrenomedullin levels during the late follicular phase of the menstrual cycle is not clear. Since it has been demonstrated that adrenomedullin is involved in the regulation of hypothalamus-pituitary-adrenal gland and its secretion is regulated by sex hormones we speculate that adrenomedullin could also play a role in regulating the hypothalamus-pituitary-ovary feedback. Alternatively it may be involved in the regulation of fluid and electrolyte homeostasis during the menstrual cycle.

Evaluation of an ambulatory system for gait analysis in hip osteoarthritis and after total hip replacement.

Spatial and temporal parameters of gait have clinical relevance in the assessment of motor pathologies, particularly in orthopaedics. A new gait analysis system is proposed which consists of (a) an ambulatory device (Physilog) including a set of miniature gyroscopes and a portable datalogger, and (b) an algorithm for gait analysis. The aim of this study was the validation of this system, for accuracy and clinical applicability. Eleven patients with coxarthrosis, eight patients with total hip arthroplasty and nine control subjects were studied using this portable system and also a reference motion analyzer and force plate. The small differences in the stance period (19 +/- ms), stride length and velocity (0.4 +/- 9.6 cm and 2.5 +/- 8.3 cm/s, respectively), as well as thigh and shank rotations (2.4 +/- 4.3 degrees and 0.3 +/- 3.3 degrees, respectively), confirmed good agreement of the proposed system with the reference system. In addition, nearly the same accuracy was obtained for all three groups. Gait analysis based on Physilog was also in agreement with their Harris Hip Scores (HHS): the subjects with lower scores had a greater limp, a slower walking speed and a shorter stride. This ambulatory gait analysis system provides an easy, reproducible and objective method of quantifying changes in gait after joint replacement surgery for coxarthrosis.

Regional migratory osteoporosis: a pathogenetic hypothesis based on three cases and a review of the literature.

Regional migratory osteoporosis (RMO) is a migrating arthralgia of the weight-bearing joints of the lower limb which mainly affects middle-aged males. Its aetiology is unknown. The association of RMO with generalised osteoporosis has recently been reported. A concurrent systemic osteoporosis was also reported in some cases of transient osteoporosis of the hip (TOH), a disorder closely related to RMO. In its turn, TOH is considered a reversible stage of avascular necrosis of the hip (AVN), and the aetiopathogenesis of both of them remains strongly debated. We report three cases of RMO associated with generalised severe idiopathic osteoporosis. Three men, in the fourth and fifth decades of life, complained of at least four episodes of arthralgia in the lower limbs, with a migratory pattern, radiographic focal osteoporosis and final clinical resolution. The most striking common feature of these patients was the presence of a severe systemic osteoporosis with a prevailing trabecular involvement. We suggest that a prolonged or exaggerated activation of regional acceleratory phenomena (RAP) is the cause of transient osteoporosis. Bone tissue microdamage due to osteoporosis may be the most frequent noxious stimulus that turns RAP on, and, bone tissue microfracture is the most prevalent consequence. When this pathogenetic pathway is activated, the progression from focal osteoporosis and bone marrow oedema to avascular necrosis is associated with the amount of structural damage.

Amniotic fluid nitric oxide metabolite levels and nitric oxide synthase localization in feto-placental tissues are modified in association with human labor.

Nitric oxide (NO) has a relaxant effect on uterine smooth muscle and may be implicated in maintaining uterine quiescence during pregnancy. In order to investigate the role of nitric oxide in human parturition, we have measured NO metabolite levels in maternal and fetal compartments in association with labor, both at term and preterm. We have also examined the localization and distribution of NO synthase (NOS) isoforms in placentas and fetal membranes after term and preterm delivery by means of immunohistochemistry. Although no differences were present in maternal and fetal blood and in maternal urine among groups, we found that NO metabolite concentrations were higher in amniotic fluid collected from women in labor than in non-laboring patients, both at term (15.4+/-1.6 vs. 6.8+/-0.6 microM/mg creatinine) and preterm (16.7+/-2.0 vs. 7.0+/-0.8 microM/mg creatinine). Ir-bNOS staining appeared to be decreased in fetal membranes collected after spontaneous labor at term and preterm. In contrast, a stronger staining for iNOS was detected in trophoblast cells of fetal membranes from women in labor than in those from non-laboring women. We suggest that NOS isoenzymes in fetal placental tissues are differently regulated and might play different roles during pregnancy.

Nitric oxide in preeclampsia: lack of evidence for decreased production.

The purpose of our study was to determine the involvement of the L-arginine-NO system in preeclampsia. We studied 26 patients with preeclampsia and 27 normotensive pregnancies. Maternal and cord plasma, urine and amniotic fluid were assayed for nitric oxide metabolites (nitrite and nitrate) using the Griess reaction. Sections of placenta and fetal membranes were immunostained with polyclonal anti-endothelial and anti-neuronal nitric oxide synthase antibodies. The concentration of nitrate in the amniotic fluid of preeclamptic patients (median 10.3 mumol/mg creatinine) was significantly higher (P < 0.001) than in the normotensive group (5.6 mumol/mg creatinine). Nitrate concentrations in maternal and cord plasma and in urine were similar in the two groups. Endothelial cells of the villi of preeclamptic placentas showed a higher positivity in endothelial nitric oxide synthase immunostaining with respect to normotensive controls. Our results indicate that feto-placental NO production is not reduced in preeclampsia. In contrast, the increased concentrations of NO metabolites in amniotic fluid and the positive immunostaining of endothelial nitric oxide synthase in the placental villi suggest that the placental L-arginine-NO system is up-regulated in preeclampsia.

Mechanobiology of engineered cartilage cultured under a quantified fluid-dynamic environment.

Natural cartilage remodels both in vivo and in vitro in response to mechanical forces and hence mechanical stimulation is believed to have a potential as a tool to modulate extra-cellular matrix synthesis in tissue-engineered cartilage. Fluid-induced shear is known to enhance chondrogenesis on animal cells. A well-defined hydrodynamic environment is required to study the biochemical response to shear of three-dimensional engineered cell systems. We have developed a perfused-column bioreactor in which the culture medium flows through chondrocyte-seeded porous scaffolds, together with a computational fluid-dynamic model of the flow through the constructs' microstructure. A preliminary experiment of human chondrocyte growth under static versus dynamic conditions is described. The median shear stress imposed on the cells in the bioreactor culture, as predicted by the CFD model, is 3 x 10(-3) Pa (0.03 dyn/cm(2)) at a flow rate of 0.5 ml/min corresponding to an inlet fluid velocity of 44.2 mum/s. Providing a fluid-dynamic environment to the cells yielded significant differences in cell morphology and in construct structure.

A comparative evaluation of chondrocyte/scaffold constructs for cartilage tissue engineering.

This study aimed to evaluate three biodegradable scaffolds as cell carriers for in vitro cartilage regeneration using mature human chondrocyte cells. We compared cell distribution, viability and morphology and we evaluated the mechanical properties of the constructs after 2 weeks of in vitro culture. The materials used as scaffolds were fibrin glue, a collagen sponge and a polyurethane foam (DegraPol(R)). Fibrin glue was found unsuitable as a chondrocyte carrier vehicle after culture times longer than a few days, probably due to significant barriers to nutrients and oxygen diffusion, and the material weakened rapidly. The collagen-based sponge was found to be unsuitable to support chondrocyte survival in vitro, although the presence of newly synthesized collagen was observed in these constructs. The synthetic biodegradable scaffold was more adequate in supporting cell survival and mechanical properties. After 2 weeks of static culture, the storage modulus obtained by dynamic shear testing was in the order of 0.7 kPa in fibrin constructs, 3.7 kPa in collagen constructs and 105 kPa in DegraPol(R) constructs. The better mechanical stability of the synthetic foam supports further investigation in the possible use of synthetic biomaterials as biodegradable scaffolds for in vitro cartilage regeneration. (Journal of Applied Biomaterials & Biomechanics 2004; 2: 55-64).

Osteointegration of 96 cementless hip prostheses with hydroxyapatite coating; 5 years follow-up.

Since 1988 at total of 96 hip prostheses with hydroxyapatite coating (HA) for both the acetabular and the femoral components have been used. HA is considered to be a biocompatible material, with a considerable capacity for osteointegration with evident osteophilia. Close integration between this material and bone tissue is determined by the formation of chemical bonds, and this leads to the development of osteoid tissue and newly-formed bone trabeculae. Based on the radiographic evaluation criteria described by Engh in 1990 and with reference to the concepts of stability and fixation of the prosthesis to the bone, it was observed that radiographic signs of osteointegration are manifested as early as 1 year after surgery, and, in particular, that the formation of bone bridges (spot welds) in the interface increases in time.

The OCTOPUS system for acetabular reconstruction.

In revision surgery of the hip, reconstruction of the acetabulum often constitutes the most complex procedure. There is frequently a considerable loss of bone substance, and correct repositioning of the rotation center of the femoral head is required. Based on surgical experience supported by clinical results the authors affirm that both of these objectives may be achieved when the OCTOPUS socket system is used. This implant, with anchoring to the iliac bone and the use of bone transplants, allows for the reconstruction of the original anatomy of the cotyle.

[Acute torsion of the greater omentum (presentation of 4 clinical cases and bibliographical notes)]. / La torsione acute del grande omento (presentazione di 4 casi clinici e note bibliografiche).

Authors present 4 cases of acute torsion of the greater omentum (2 cases primary, 2 cases secondary. They analyze a short review of the literature and point of the rarity of this disease that, mimicking an acute appendicitis, make difficult right diagnosis before surgery.

[Unusual cause of post-traumatic hemoperitoneum: rupture of enterogenous cysts]. / Insolita causa di emoperitoneo post-traumatico: rottura di cisti enterogena.

Authors present a rare complication of multiple enteric cystes: hemoperitoneum. A little girl 4 years old was operated on by suspected acute appendicitis. The surgery showed hemoperitoneum by bleeding from broken (post-traumatic) paradigiunal cyst. Other 5 cystes were present near the first one. Authors review shortly some titles of bibliography about duplication of the alimentary tract and hemoperitoneum.