10 resultados para intrauterine devices
em DigitalCommons@The Texas Medical Center
Resumo:
Despite advances in effective and long-acting contraceptive methods and the introduction into health care that an initial unplanned pregnancy allows, repeat unplanned pregnancy continues to affect Hispanic adolescents at a rate higher than that of non-Hispanic whites. The current study was undertaken to identify and categorize factors associated with uptake of long acting contraception (implant or intrauterine devices) or consistent use of highly effective methods (injectable DMPA, ring, patch, or pills), among Hispanic/Latina teens who have previously given birth. ^ I searched Ovid Medline, Pubmed, CINAHL, PsychINFO, POPLINE and Scopus, and reference lists for studies in English, ≥1980, of original data from the United States on factors related to initiation, maintenance, or discontinuation of contraceptive methods in postpartum or parenting adolescent females. I then identified articles that specified the inclusion of Hispanics/Latinas in the study population and either reported findings specific to race/ethnicity or used race/ethnicity as an independent variable in analyses of contributing factors. I then extracted data for each study and categorized independent variables as predisposing, enabling, or reinforcing following the PRECEDE model.1 Factors found to be associated with contraception use or non-use were combined to create a logic model of risk. ^ Of 9 eligible studies, one solely addressed initiation; one, initiation and maintenance; two, initiation and discontinuation; three, maintenance; and two, maintenance and discontinuation. There was some overlap in the studies' assessments of maintenance and discontinuation and the author(s) often did not distinguish between the two. Nearly all (k=7) were prospective observational studies with convenience samples and bivariate analyses (k=6). One study was initially a quasi-experimental design but became a prospective cohort due to extremely high attrition. Sociodemographic characteristics and predisposing factors were studied frequently, as were reinforcing factors; enabling factors were discussed infrequently and only in studies involving focus groups or interviews. Due to a paucity of research, a consensus of factors found consistently to influence the contraception behavior of postpartum Latina teens could not be established for the overall population nor for cultural subgroups. Future research is needed that focuses on postpartum/parenting Latina teens, with subgroup identification and differentiation, to determine the prevalent and pertinent predisposing, enabling, and reinforcing factors related to effective contraception initiation and maintenance.^
Resumo:
This study compared the effectiveness of topical benzocaine 20% versus a combination of lidocaine, tetracaine, and phenylephrine in providing sufficient analgesia for the placement of orthodontic temporary anchorage devices (TADs). The 2 topical anesthetics were tested against each other bilaterally using a randomized, double-blind, crossover design. The agents were left in place for the amount of time prescribed by the manufacturer. The TAD was then placed, and each subject rated the degree of pain on a Heft-Parker visual analogue scale. A pulse oximeter was used to record the preoperative and postoperative pulse rates. Statistically significant differences in perceived pain (P < .05) and success rate (P < .01) between drugs were seen, but no significant difference in pulse rate change between the topical anesthetics was observed (P > .05). It was concluded that when the efficacy of topical benzocaine and of a combination product was compared as the sole anesthetic to facilitate acceptable pain control for placement of orthodontic temporary anchorage devices, the combination product was considerably more efficacious.
Resumo:
This paper introduces an extended hierarchical task analysis (HTA) methodology devised to evaluate and compare user interfaces on volumetric infusion pumps. The pumps were studied along the dimensions of overall usability and propensity for generating human error. With HTA as our framework, we analyzed six pumps on a variety of common tasks using Norman’s Action theory. The introduced method of evaluation divides the problem space between the external world of the device interface and the user’s internal cognitive world, allowing for predictions of potential user errors at the human-device level. In this paper, one detailed analysis is provided as an example, comparing two different pumps on two separate tasks. The results demonstrate the inherent variation, often the cause of usage errors, found with infusion pumps being used in hospitals today. The reported methodology is a useful tool for evaluating human performance and predicting potential user errors with infusion pumps and other simple medical devices.
Resumo:
Growth-restricted fetuses are at risk for a variety of lifelong medical conditions. Preeclampsia, a life-threatening hypertensive disorder of pregnancy, is associated with fetuses who suffer from intrauterine growth restriction (IUGR). Recently, emerging evidence indicates that preeclamptic women harbor AT(1) receptor agonistic autoantibodies (AT(1)-AAs) that contribute to the disease features. However, the exact role of AT(1)-AAs in IUGR and the underlying mechanisms have not been identified. We report that these autoantibodies are present in the cord blood of women with preeclampsia and retain the ability to activate AT(1) receptors. Using an autoantibody-induced animal model of preeclampsia, we show that AT(1)-AAs cross the mouse placenta, enter fetal circulation, and lead to small fetuses with organ growth retardation. AT(1)-AAs also induce apoptosis in the placentas of pregnant mice, human villous explants, and human trophoblast cells. Finally, autoantibody-induced IUGR and placental apoptosis are diminished by either losartan or an autoantibody-neutralizing peptide. Thus, these studies identify AT(1)-AA as a novel causative factor of preeclampsia-associated IUGR and offer two possible underlying mechanisms: a direct detrimental effect on fetal development by crossing the placenta and entering fetal circulation, and indirectly through AT(1)-AA-induced placental damage. Our findings highlight AT(1)-AAs as important therapeutic targets.
Devices in heart failure: potential methods for device-based monitoring of congestive heart failure.
Resumo:
Congestive heart failure has long been one of the most serious medical conditions in the United States; in fact, in the United States alone, heart failure accounts for 6.5 million days of hospitalization each year. One important goal of heart-failure therapy is to inhibit the progression of congestive heart failure through pharmacologic and device-based therapies. Therefore, there have been efforts to develop device-based therapies aimed at improving cardiac reserve and optimizing pump function to meet metabolic requirements. The course of congestive heart failure is often worsened by other conditions, including new-onset arrhythmias, ischemia and infarction, valvulopathy, decompensation, end-organ damage, and therapeutic refractoriness, that have an impact on outcomes. The onset of such conditions is sometimes heralded by subtle pathophysiologic changes, and the timely identification of these changes may promote the use of preventive measures. Consequently, device-based methods could in the future have an important role in the timely identification of the subtle pathophysiologic changes associated with congestive heart failure.
Resumo:
Due to the clinical success of left ventricular assist devices (LVADs) used for short term "bridge to transplant" and the limited availability of donor organs, heart assist devices are being considered for long term implantation as an alternative to heart transplantation. In an effort to improve biocompatibility, a nonthrombogenic cellular lining was developed from genetically engineered smooth muscle cells (GE-SMC) for the Thermocardiosystems Heartmate$\sp{\rm TM}$ LVAD. SMCs have been transduced with the genes for endothelial nitric oxide synthase (NOS III) and GTP cyclohydrolase (GTPCH) with subsequent stable expression of the NOS III protein via an Epstein Barr based DNA expression vector. Transduced SMCs produce nitric oxide at concentrations that reduce platelet deposition and smooth muscle cell proliferation when tested in vitro. In addition, the adhesive capabilities of GE-SMC linings were also examined, and optimized in physical environments mimicking typical in vivo LVAD operation. Preliminary investigations examining cell adhesion during constant shear stress exposure demonstrated an acute phase of cell loss corresponding to cytoskeletal F-actin rearrangement. Subsequently, an in vitro circulatory loop was designed to expose cell lined LVADs to in vivo operating conditions. Cumulative cell loss from cell lined LVADs was less than 10% after 24 hours of flow. Using a protocol for "preconditioning" the cell lining within the mock circulatory loop, the first implantation of an LVAD containing a genetically engineered SMC lining was successfully implemented in a bovine model. Results from this 24 hour study indicate that the flow-conditioned cellular lining remained intact with no evidence of thromboembolization and only minimal changes in coagulation studies. ^
Resumo:
The persistence of low birth weight and intrauterine growth retardation (IUGR) in the United States has puzzled researchers for decades. Much of the work that has been conducted on adverse birth outcomes has focused on low birth weight in general and not on IUGR. Studies that have examined IUGR specifically thus far have focused primarily on individual-level maternal risk factors. These risk factors have only been able to explain a small portion of the variance in IUGR. Therefore, recent work has begun to focus on community-level risk factors in addition to the individual-level maternal characteristics. This study uses Social Ecology to examine the relationship of individual and community-level risk factors and IUGR. Logistic regression was used to establish an individual-level model based on 155, 856 births recorded in Harris County, TX during 1999-2001. IUGR was characterized using a fetal growth ratio method with race/ethnic and sex specific mean birth weights calculated from national vital records. The spatial distributions of 114,460 birth records spatially located within the City of Houston were examined using choropleth, probability and density maps. Census tracts with higher than expected rates of IUGR and high levels of neighborhood disadvantage were highlighted. Neighborhood disadvantage was constructed using socioeconomic variables from the 2000 U.S. Census. Factor analysis was used to create a unified single measure. Lastly, a random coefficients model was used to examine the relationship between varying levels of community disadvantage, given the set of individual-level risk factors for 152,997 birth records spatially located within Harris County, TX. Neighborhood disadvantage was measured using three different indices adapted from previous work. The findings show that pregnancy-induced hypertension, previous preterm infant, tobacco use and insufficient weight gain have the highest association with IUGR. Neighborhood disadvantage only slightly further increases the risk of IUGR (OR 1.12 to 1.23). Although community level disadvantage only helped to explain a small proportion of the variance of IUGR, it did have a significant impact. This finding suggests that community level risk factors should be included in future work with IUGR and that more work needs to be conducted. ^
Resumo:
Birth defects occur in 1 of every 33 babies born in the United States, and are the leading cause of infant death. Mothers using contraceptives that become pregnant may continue to use their contraceptives after their first missed menstrual period, thus exposing their baby in utero to the contraceptive product. Progesterone is also sometimes prescribed during the first trimester of pregnancy to mothers with a history of miscarriages or infertility problems. To ensure the safety of these products, it is important to investigate whether there is an increased occurrence of babies born with birth defects to mothers using various contraceptive methods or progesterone in early pregnancy. Using data from the National Birth Defects Prevention Study (NBDPS), an ongoing multi-state, population based case-control study, this study assessed maternal exposures to IUDs, spermicides, condoms and progesterone in early pregnancy. ^ Progesterone used for threatened miscarriage during the first three months of pregnancy was associated with an increased occurrence of hypoplastic left heart (adjusted odds ratios (OR) 2.24, 95% CI 1.13-4.21), perimembranous ventricular septal defects (OR 1.64, 95% CI 1.10-2.41), septal associations (OR 2.52, 95% CI 1.45-4.24), esophageal atresia (OR 1.82, 95% CI 1.04-3.08), and hypospadias (OR 2.12, 95% CI 1.41-3.18). Mothers using progesterone for injectable contraception had increased (OR > 2.5), but insignificant odds ratios for anencephaly, septal associations, small intestinal atresias and omphalocel. Progesterone used for fertility was not associated with an increased occurrence of any birth defects examined. ^ Mothers using progesterone for fertility assistance and threatened miscarriage were very similar with respect to their demographics and pregnancy history. They also both reported similar types of progesterone. Thus, if progesterone was a causal risk factor for birth defects we would have expected to observe similar increases in risk among mothers using progesterone for both indications. Because we predominantly observed increased associations among mothers using progesterone for threatened miscarriage but not fertility assistance, it is possible the increased associations we observed were confounded by indication (i.e. progesterone was administered for vaginal bleeding which occurred as a sequelae to the formation of a congenital anomaly. ^ No significant increased associations were observed between maternal spermicide use during pregnancy and 26 of 27 types of structural malformations. While multiple statistical tests were performed we observed first trimester maternal spermicide use to be associated with a significant increased occurrence of perimembranous ventricular septal defects (OR 2.21, 95% CI 1.16-4.21). A decreased occurrence (OR < 1.0) was observed for several categories of birth defects among mothers who conceived in the first cycle after discontinuing the use of spermicides (22 of 28) or male condoms (23 of 33). ^ Overall the percent of IUD use was similar between mothers of controls and mothers of all cases in aggregate (crude OR 1.05, 95% CI 0.61-1.84). Power was limited to detect significant associations between IUD use and birth defects, however mothers using an IUD in the month immediately prior to conception or during pregnancy were not associated with an increase of birth defects. Limb defects and amniotic band sequence previously reported to be associated with IUD use during pregnancy were not found to occur among any mothers reporting the use of an IUD during pregnancy.^
Resumo:
Background. The number of infections of cardiac implantable electronic devices (CIED) continues to escalate out of proportion to the increase rate of device implantation. Staphylococcal organisms account for 70% to 90% of all CIED infections. However, little is known about non-staphylococcal infections, which have been described only in case reports, small case series or combined in larger studies with staphylococcal CIED infections, thereby diluting their individual impact. ^ Methods. A retrospective review of hospital records of patients admitted with a CIED-related infections were identified within four academic hospitals in Houston, Texas between 2002 and 2009. ^ Results. Of the 504 identified patients with CIED-related infection, 80 (16%) had a non-staphylococcal infection and were the focus of this study. Although the demographics and comorbities of subjects were comparable to other reports, our study illustrates many key points: (a) the microbiologic diversity of non-staphylococcal infections was rather extensive, as it included other Gram-positive bacteria like streptococci and enterococci, a variety of Gram-negative bacteria, atypical bacteria including Nocardia and Mycobacteria, and fungi like Candida and Aspergillus; (b) the duration of CIED insertion prior to non-staphylococcal infection was relatively prolong (mean, 109 ± 27 weeks), of these 44% had their device previously manipulated within a mean of 29.5 ± 6 weeks; (c) non-staphylococcal organisms appear to be less virulent, cause prolonged clinical symptoms prior to admission (mean, 48 ± 12.8 days), and are associated with a lower mortality (4%) than staphylococcal organisms; (d) thirteen patients (16%) presented with CIED-related endocarditis; (e) although not described in prior reports, we identified 3 definite and 2 suspected cases of secondary Gram-negative bacteremia seeding of the CIED; and (f) inappropriate antimicrobial coverage was provided in approximately 50% of patients with non-staphylococcal infections for a mean period of 2.1 days. ^ Conclusions. Non-staphylococcal CIED-related infections are prevalent and diverse with a relatively low virulence and mortality rate. Since non-staphylococcal organisms are capable of secondarily seeding the CIED, a high suspicion for CIED-related infection is warranted in patients with bloodstream infection. Additionally, in patients with suspected CIED infection, adequate Gram positive and -negative antibacterial coverage should be administered until microbiologic data become available.^
Resumo:
Objective: The primary objective of this project was to describe the efficacy of the Levonorgestrel Intrauterine Device (LIUD) for treatment of Complex Endometrial Cancer (CAH) and Grade 1 Endometrial Cancer (G1EEC) in terms of rate of Complete Response (CR) and Partial Response (PR) after 6 months of therapy. Finally, we assessed if any clinical or pathologic features were associated with response to the LIUD. ^ Methods: This study was a retrospective case series designed to report the response rate of patients with CAH or G1EEC treated with LIUD therapy. In addition, this study has a laboratory component to assess molecular predictors of response to LIUD therapy. Retrospective data already collected from patients diagnosed with CAH or EEC grade 1 and treated with LIUD therapy at MD Anderson Cancer Center (MDACC) were used for this study. Patients from all ethnic and race groups were included. A Complete Response (CR) was defined in patients diagnosed with CAH if pathologic report at 6 months demonstrated either no evidence of hyperplasia or no atypia in the setting of simple or complex hyperplasia. Partial Response (PR) was recorded if disease downgraded to only CAH from G1EEC. No Response (NR) was recorded if pathologic report demonstrates no change (Stable Disease, SD) or progression to cancer (Progressive Disease, PD). We calculated the proportion of patients with complete response to LIUD therapy with 95% confidence interval. We compared the response rates (CR/PR vs NR) by obesity status (Obese if BMI > 40 kg/m2 vs non-obese if BMI <= 40 kg/m2) as well as other clinical and pathologic factors, such as age, uterine size (median size), and presence of exogenous progesterone effect. ^ Results: There were 39 patients diagnosed with either CAH or G1EEC treated with the LIUD. Of 39 patients, 12 did not have pathological results of biopsy at 6months time period. Of 27 evaluable patients, 17 were diagnosed with CAH and 10 with G1EEC. Overall response rate (RR) was 78% (95% CI = 62-94%) at 6 months, 18 patients had CR (4 in G1EEC; 14 in CAH), 3 patients had PR (3 in G1EEC), 3 had SD (1 in CAH; 2 in G1EEC), 3 had PD (2 in CAH; 1 in G1EEC). After histology stratification, RR at 6 months was 82.35% (14/17; 95%CI = 67.4-97.3%) in CAH and 70% (7/10; 95% CI = 41-98.4%) in G1EEC. ^ There was no difference in response (R) and no response (NR) based on BMI (p=0.56). He observed a trend showing association between age with response (p=0.1). There was no association between uterine size and response to therapy (p=0.17). We recorded strong association between exogenous progesterone effect and response. ^ Conclusion: LIUD therapy for the treatment of CAH and G1EEC may be effective and safe. Presence of exogenous progesterone effect may predict the response to LIUD therapy at earlier time points. There is need of further studies with larger sample size to explore the relationship of response with other clinical and pathologic factors^