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Nursing protocol for diaphragm contraception.
The diaphragm is becoming the more popular method of birth control in the United States. When used properly, it is a safe and effective alternative for those women who are unable to take birth control pills or prefer another method. The protocol presented here is a comprehensive approach to diaphragm fitting, client instruction and follow-up. The practitioner utilizing such an approach will insure a safe and highly effective method of birth control to those patients who choose the diaphragm as their method of contraception.
A study of the relationship between tensile testing of condoms and breakage in use.
The ability of the condom wall to maintain its integrity throughout sexual intercourse is critical to its role in halting the spread of major sexually transmissible pathogens including the human immunodeficiency virus. There are three principal in vitro performance tests applied to condoms: a test for freedom from holes, an inflation test, and tensile testing. In this study we subjected condoms that had broken in use to tensile tests in order to determine any correlation between their in vivo and in vitro performance. Condoms which had broken in use showed similar tensile properties to those which had not. All passed all tensile test criteria. Thus, the inclusion of tensile testing in National Standards for condoms is not sufficient to insure strong products.
Efficacy of thermoplastic elastomer and latex condoms as viral barriers.
The barrier efficacy of a thermoplastic elastomer (TPE) and three brands of latex condoms was compared in a passive-leak test and in a dynamic model of simulated intercourse. Fifteen replicates of each of the condoms were challenged with bacteriophage T7 (100 nm) and the polio virus Type 1 (PV-1, 27 nm). In the passive test, no condom leaked either virus. In the dynamic model, no TPE condoms leaked either virus and no latex condoms leaked T7. Two samples of one commercially available latex condom leaked T7 but not PV-1. These data support that intact latex condoms are effective in vivo viral barriers and extend the finding to TPE condoms as well. Given its substantial equivalence to latex as a viral barrier, TPE condoms are an alternative choice for individuals with latex allergies. The TPE material is also more resistant to common environmental conditions that affect latex adversely and should therefore be a superior choice if condoms must be stored for extended periods in suboptimal conditions.
Test method for evaluating the permeability of intact prophylactics to viral-size microspheres under simulated physiologic conditions.
The alarming number of AIDS cases has increased the attention given to barrier devices such as condoms. The authors describe a new test method that evaluates the permeability of the intact condom when subjected to simulated physiologic conditions. Fluorescent-labelled polystyrene microspheres (110 nm diameter) are used to model cell-free virus. Physical and chemical conditions that are present during coitus, such as pressure, pH, and temperature, are considered in the design of the method. The testing chamber is designed to be continuously monitored for changes in fluorescence due to leakage across the condom surface. The sensitivity of the system is 1 x 10(-5) of the original concentration of microsphere solution (3.4 x 10(11) particles/mL), which corresponds to leak rates as small as .001 microL/sec. The test provides an in vitro test of barrier material permeability relevant to actual use.
Effectiveness of latex condoms as a barrier to human immunodeficiency virus-sized particles under conditions of simulated use.
Condoms were tested in an in vitro system simulating key physical conditions that can influence viral particle leakage through condoms during actual coitus. The system quantitatively addresses pressure, pH, temperature, surfactant properties, and anatomical geometry. A suspension of fluorescence-labeled, 110-nm polystyrene microspheres models free human immunodeficiency virus (HIV) in semen, and condom leakage is detected spectrofluorometrically. Leakage of HIV-sized particles through latex condoms was detectable (P less than 0.03) for as many as 29 of the 89 condoms tested. Worst-case condom barrier effectiveness (fluid transfer prevention), however, is shown to be at least 10(4) times better than not using a condom at all, suggesting that condom use substantially reduces but does not eliminate the risk of HIV transmission.
Condoms: a wider range needed.
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Condom trade barriers come down across Europe.
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An actual use comparison of condoms meeting Australian and Swiss standards: results of a double-blind crossover trial.
The performance of condoms in actual use has been poorly researched in the past, especially in comparing condoms that met different quality control standards as indicated by laboratory testing. The present study used a double-blind crossover design to compare the performance of 2 types of condoms in actual use; one that met the Australian and International Organization for Standardization (ISO) standards for condom quality and one that met the more stringent Swiss Quality Seal requirements. Ninety-two men recruited from Metropolitan Melbourne completed a self-report diary sheet after each condom was used which assessed the performance of the condom and the conditions under which it was used. From a total of 1917 condom uses, there was an overall breakage risk of 2.7%. The breakage risk ratio (Australian/ISO:Swiss) for all types of use was 1.16 (95% confidence interval 0.68-1.99). When subanalyses by method of entry were performed, the condoms meeting the Swiss standard appeared to fare better than the Australian/ ISO standards for anal sex (RR = 4.84, 95% CI 1.07-21.8, P = 0.022), while the opposite was the case for vaginal sex (RR = 0.74, 95% CI 0.35-1.53, P = 0.41). The result for anal use was statistically significant at the 5% level, despite being based on fewer condom trials than that for vaginal use, but this result needs to be replicated. Although the participants appeared representative of the general male population in Melbourne in the age bracket 18-46 years, there was a significant history of condom usage reported. This may have influenced the risk of breakage.
Selected legal developments in reproductive health in 1991.
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Condoms--a new look.
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[On examination of commerical condoms].
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[Damage to condoms caused by vaginally administered drug].
A 28-year-old woman who was treated for vaginal candidiasis with Gyno-Daktarin vaginal capsules (miconazole nitrate) became pregnant because a condom used during intercourse had ruptured. Incubation in vitro with 400 and 1200 mg miconazole nitrate vaginal capsules (Gyno-Daktarin 3 and Gyno-Daktarin I), but not miconazole nitrate vaginal cream (20 mg/g), was shown to damage rubber condoms. Patients using vaginal medicines should be aware of a possible adverse effect on rubber condoms or contraceptive diaphragms and a subsequent increased risk of pregnancy or contagious diseases such as AIDS. Fatty excipients such as glycerin, paraffin, petrolatum or Witepsol may be involved.
Are vaccination rates higher if providers receive free vaccines and follow contraindication guidelines?
BACKGROUND AND OBJECTIVES: Economics has been suggested as a barrier to vaccination, but data that link clinician reports to actual immunization rates are limited. This study examined the relationship between clinicians' self-report regarding likelihood of vaccinating and actual age at vaccination from a registry of children seen by the clinicians. METHODS: Standardized telephone survey results of 29 providers were compared to the immunization records of children seeing these providers, using analysis of contingency tables (on time versus late) and conditional hierarchical linear models with log age at diphtheria-tetanus-pertussis (DTP)#3, DTP#4, and measles-mumps-rubella (MMR)#1 as the dependent variables. RESULTS: Children seeing providers likely to refer an uninsured child for immunization were vaccinated at a later log age at DTP#4 but not for DTP#3 or MMR#1 than children seeing providers unlikely to refer. Vaccination rates were higher for MMR#1 (77% versus 48%), DTP#3 (84% versus 71%), and DTP#4 (82% versus 66%) among providers who received free vaccine, compared with children seen by providers who did not receive free vaccine. These results remained significant in the hierarchical analyses. Providers likely to vaccinate an 18-month-old with watery diarrhea had higher vaccination rates than those unlikely to vaccinate for MMR#1, DTP#3, and DTP#4; the results were also significant in the hierarchical analyses. CONCLUSION: Children are vaccinated later in the practices of providers who are likely to refer uninsured children to a public vaccine clinic for vaccination, who do not receive free vaccine supplies, or who overinterpret contraindications.
Distribution kinetics of salicylic acid in the dual-perfused rat liver preparation.
The hepatic distribution kinetics of salicylic acid was determined using a single-pass dual hepatic artery (HA) and portal vein (PV) perfused in situ rat liver preparation. Bolus doses of [14C]salicylic acid and of reference markers ([3H]-water and [14C]-sucrose) were injected in a random order into either the HA or PV and then, after an appropriate interval, into the alternate vessel. The hepatic outflow profile of [14C]salicylic acid displayed a characteristic sharp peak followed by a slower eluting tail, whereas sucrose and water displayed unimodal outflow profiles. The biphasic outflow profile indicates that the hepatic distribution of salicylic acid is not instantaneous but is limited by a permeability barrier. The in situ permeability surface area product for [14C]salicylic acid was 3.35 +/- 0.26 ml/min/g for PV and 7.45 +/- 1. 50 ml/min/g for HA administration. Furthermore, theory dictates that hepatic uptake is influenced by both perfusion and permeability if effective permeability surface area product/blood flow ratio lies between the values of 0.06 and 7.0. Our estimates (3.0 for venous output and 6.7 for arterial input) indicate that hepatic uptake of salicylic acid is dependent on both perfusion and permeability. The volume terms were calculated using two different methods, standard and specific. Regardless of the compound and method, the volume of distribution after arterial administration was larger than that after venous administration. In addition, a volume of distribution approximately twice that of the total aqueous space (i.e., HA, 2.23 +/- 0.13 versus 1.10 +/- 0.07 ml/g; PV, 1.72 +/- 0.16 versus 0.68 +/- 0.04 ml/g) implies that salicylic acid has a significant affinity for hepatic tissue. A similar tissue-to-perfusate partition coefficient associated with HA and PV input (5.40 +/- 0.38 versus 6. 48 +/- 0.56) indicates that affinity of salicylic acid for hepatic tissue is independent of the route of input.
Latex condom deterioration accelerated by environmental factors: I. Ozone.
Commercial non-lubricated latex condoms were unpackaged and exposed in an environmental chamber to ozone levels (0.3 ppm) commonly present in urban smog conditions. Deterioration was observed by scanning electron microscopy after 18 hours exposure. Loss of mechanical strength was quantitated by measurement of the air pressures necessary to burst the condom and volumes at burst. After 24 hours exposure to ozone the latex surface was covered with craters and after 48 hours the pressure required to burst the condom was 44% that of control samples. Data suggest the need for study of the effectiveness of lubrication and packaging in protecting condoms from environmental factors which may accelerate deterioration.
In vitro percutaneous absorption of arildone, a highly lipophilic drug, and the apparent no-effect of the penetration enhancer Azone in excised human skin.
PURPOSE: Arildone, a novel lipophilic antiviral drug when evaluated in Clinical Trials showed limited skin absorption and antiviral efficacy. These studies were conducted to explain the apparent poor absorption characteristics and attempt to promote skin absorption by using Azone, a penetration enhancer. METHODS: Standard in vitro skin permeation methods using excised human skin were employed to characterise the absorption of Arildone. 14C-Arildone was used to estimate the distribution in skin layers by scintigraphic and autoradiographic procedures. RESULTS: The aqueous solubility and distribution constant values for Arildone were 2 micrograms ml-1 and 5 x 10(5) (isopropyl myristate/water), respectively. Absorption through full thickness skin or stratum corneum-viable epidermal membranes (diffusional resistant dermis removed), from a propylene glycol vehicle, was slow and the addition of Azone had no effect on the permeation rate. Distribution studies showed accumulation of Arildone in the stratum corneum. The concentration of Arildone in the viable epidermis was estimated from sectioning the skin and was found to be in sufficient amounts (400 micrograms cm-3) to have potential antiviral activity. CONCLUSIONS: The apparent accumulation of Arildone in the stratum corneum suggested that the hydrophilic skin region presented the main barrier to permeation. Azone which affected the permeability of the stratum corneum was therefore not effective at enhancing Arildone absorption. Vehicles which readily permeate and enhance the transfer of lipophilic drugs from the stratum corneum into the viable epidermis were recommended.
Optical measurement of isolated canine lung filtration coefficients after alloxan infusion.
In this study, lung filtration coefficient (Kfc) was measured in eight isolated canine lung preparations by using three methods: standard gravimetric (Std), blood-corrected gravimetric (BC), and optical. The lungs were held in zone III conditions and were subjected to an average venous pressure increase of 8.79 +/- 0.93 (mean +/- SD) cmH2O. The permeability of the lungs was increased with an infusion of alloxan (75 mg/kg). The resulting Kfc values (in milliliters . min-1 . cmH2O-1 . 100 g dry lung weight-1) measured by using Std and BC gravimetric techniques before vs. after alloxan infusion were statistically different: Std, 0.527 +/- 0.290 vs. 1. 966 +/- 0.283; BC, 0.313 +/- 0.290 vs. 1.384 +/- 0.290. However, the optical technique did not show any statistical difference between pre- and postinjury with alloxan, 0.280 +/- 0.305 vs. 0.483 +/- 0. 297, respectively. The alloxan injury, quantified by using multiple-indicator techniques, showed an increase in permeability and a corresponding decrease in reflection coefficient for albumin (sigmaf). Because the optical method measures the product of Kfc and sigmaf, this study shows that albumin should not be used as an intravascular optical filtration marker when permeability is elevated. However, the optical technique, along with another means of measuring Kfc (such as BC), can be used to calculate the sigmaf of a tracer (in this study, sigmaf of 0.894 at baseline and 0.348 after injury). Another important finding of this study was that the ratio of baseline-to-injury Kfc values was not statistically different for Std and BC techniques, indicating that the percent contribution of slow blood-volume increases does not change because of injury.