RESUMEN
BACKGROUND: Consent for cornea donation from non-heart-beating donors is often requested by means of telephone interviews with relatives of the deceased. The purpose of this study was to identify the effect of specifically tailored interviewer communications training among other factors related to obtaining consent. METHODS: A retrospective analysis of consent requests made by the Aachen Cornea Bank was performed. Interviews were conducted via telephone by 26 ophthalmic residents or fellows in accordance with German and European laws and guidelines. Multiple logistic regression was used to identify factors related to the consent. Results were expressed as odds ratios (OR), 95% confidence interval (95% CI), and Wald P value. RESULTS: In 1694 interviews, the overall consent rate was 50.12%. Multivariate analysis identified 4 significant factors associated with the donation decision. Completion of a specific communication training seminar increased odds of consent by 1.533 (95% CI, 1.250-1.880; P < 0.0001). The individual interviewer had an impact on the OR of up to 1.255 (95% CI, 1.113-1.417; P = 0.0002). The odds for consent were inversely correlated with the clinical experience of the interviewer (OR, 0.884; 95% CI, 0.831-0.938; P < 0.0001). The consulted family member was 0.894 times less likely to grant consent for donation with each increase in degree of blood relation (95% CI, 0.849-0.940; P < 0.0001). CONCLUSIONS: A telephone interview is effective for obtaining consent for cornea donation. The consent decision may be associated with factors relating to the interviewer as well as the consulted family member. Specific training for cornea bank staff may increase the odds of obtaining consent.
Asunto(s)
Comunicación , Trasplante de Córnea , Consentimiento Informado , Donantes de Tejidos , Obtención de Tejidos y Órganos/métodos , Anciano , Muerte , Familia , Femenino , Alemania , Humanos , Masculino , Persona de Mediana Edad , Motivación , Oportunidad Relativa , Relaciones Profesional-Paciente , Análisis de Regresión , Estudios Retrospectivos , TeléfonoRESUMEN
PURPOSE: Corneas harvested post-mortem are at risk of contamination, therefore antibiotic additives are used in cold storage and organ culture systems. In the latter, sterility testing of the medium is part of the standard protocol. Intuitively, testing after longer organ culture periods should be more likely to detect contaminations than early testing, but may delay allocation. This study evaluates whether an optimal time for detection of donor cornea contamination can be identified. METHODS: The study complies with the Declaration of Helsinki. All procedures were supervised using a certified quality management system (ISO 9001:2000). Donor corneas harvested by enucleation or corneoscleral excision over 5 consecutive years were processed according to German and EC laws and guidelines. The corneas were stored in a closed organ culture system in 100 ml MEM containing penicillin, streptomycin and amphotericin B at 31 degrees C for up to 28 days without media exchange. In 762 corneas, 10 ml samples of medium, obtained between days 3 and 8 of culture, were tested for sterility in an automated detection system (BacT/ALERT, bioMérieux). In 424 corneas, a second sterility test was performed from the same medium before release. Contamination detection probabilities were related to the culture duration before the primary test (Cochran-Armitage). RESULTS: Overall, 19 contaminations were found. Contaminations were bilateral in four donors. One contamination was apparent by macroscopic inspection of the medium prior to the primary sterility test; 12 were detected upon primary sterility testing. Furthermore, six primarily undetected contaminations were observed: five in the secondary sterility test and one suspected microscopically. In most cases, contamination could also be seen by medium turbidity and acidification, but in three cases macroscopic medium changes were significantly delayed or absent. No trends were found between the times of primary sterility sampling and both positive and false negative test outcome probabilities. CONCLUSION: Detection probability of contaminations in organ culture media does not increase between days 3 and 8; therefore, sterility can be tested on day 3. With the recommended follow-up after sterility testing being 7 days, microbiologic release can take place after 10 days of culture. Nevertheless, the testing is not failsafe, and should always be combined with macroscopic inspection of the media.
Asunto(s)
Córnea/microbiología , Medios de Cultivo , Técnicas de Cultivo de Órganos , Donantes de Tejidos , Bacterias/aislamiento & purificación , Trasplante de Córnea , Bancos de Ojos , Hongos/aislamiento & purificación , Humanos , Preservación de Órganos , Estudios Retrospectivos , Recolección de Tejidos y ÓrganosRESUMEN
The introduction of amniotic membrane (AM) transplantation in ophthalmic surgery holds great promise and in many clinical situations it offers an alternative to existing management options. The purpose of this study was to examine the influence of established sterilization and preservation procedures on biophysical and histological properties of AM grafts. Amnion was sterilized by peracetic acid/ethanol sterilization [PES] and preserved by air-drying (sterile laminar flow) [AD] or in glycerol [GLYC]. Unsterilized AM were preserved at -80 degrees C [-80 degrees C] and served as an experimental control. Amnion allografts were characterized by the determination of their thickness, moisture vapour permeability (MVP), oxygen permeability (OPERM), tensile strength and sulphur content. Immunostaining for tissue-specific and basement membrane-related proteins was performed. Differences in biophysical parameters were found between the unsterilized allografts and the sterilized, air-dried or glycerol-preserved allografts. [PES/AD] showed the highest MVP and OPERM, the highest tensile strength and the lowest sulphur content and thickness. [PES/GLYC] exhibited the lowest OPERM and the highest thickness compared to [-80 degrees C] and [PES/AD]. Collagen types V and VII were preserved the best in the control group. Sterilization and preservation affect biophysical properties important for the use of AM as allogenic grafts. It has to be determined if any change, as noted, has a clinical impact.
Asunto(s)
Amnios/fisiología , Esterilización , Conservación de Tejido , Trasplantes , Algoritmos , Amnios/trasplante , Amnios/ultraestructura , Fenómenos Biofísicos , Biofisica , Permeabilidad de la Membrana Celular/fisiología , Femenino , Humanos , Oxígeno/metabolismo , Embarazo , Esterilización/métodos , Resistencia a la Tracción/fisiología , Conservación de Tejido/métodos , Agua/metabolismoRESUMEN
OBJECTIVE: The objective of this evaluation was to model ocular pharmacokinetics of fluorescein administered as conventional eye drops and as lyophilisate to healthy volunteers in order to assess the relative bioavailability of the lyophilisate formulation. METHODS: A total of 44 healthy subjects received equivalent doses of fluorescein as lyophilisate to one eye and as eye drops to the fellow eye in three individual studies. Fluorescein concentrations in the cornea and anterior chamber were measured by fluorophotometry. Data were analyzed by noncompartmental methods (WinNonlin software) and by compartmental population pharmacokinetic methods (NONMEM software). RESULTS: Compared to eye drops, both maximum fluorescein concentrations (C(max)) and the areas under the concentration-time curve (AUC(0-t )) values of fluorescein in the cornea and anterior chamber for lyophilisate were increased in the noncompartmental analysis: mean lyophilisate C(max) in the studies was 6.3- to 14.6-fold higher and mean AUC(0-t ) was 4.7- to 8.9-fold higher for ocular concentrations in the three studies. A three-compartment open model with first-order elimination from the anterior chamber adequately described population data. Estimated fluorescein systemic bioavailability (F) via the ocular route from lyophilisate relative to eye drops was 3.7-fold higher (95% CI 2.6-4.8). CONCLUSION: The data clearly show a considerably superior intraocular bioavailability of fluorescein when given as lyophilisate compared to conventional eye drops. There is a clear pharmacokinetic advantage of the lyophilisate preparation.