Factors associated with topographic changes of the optic nerve head induced by acute intraocular pressure reduction in glaucoma patients.

PURPOSE: To investigate factors associated with changes in optic nerve head (ONH) topography after acute intraocular pressure (IOP) reduction in patients with primary open-angle glaucoma (POAG). METHODS: Untreated POAG patients (IOP >21 mm Hg) were prospectively enrolled. Systemic and ocular information were collected, including central corneal thickness (CCT) and corneal hysteresis (CH). All patients underwent confocal scanning laser ophthalmoscopy and tonometry (Goldmann) before and 1 h after pharmacological IOP reduction. The mean of three measurements was considered for analysis. Changes in each ONH topographic parameter were assessed (one eye was randomly selected), and those that changed significantly were correlated with patient's systemic and ocular characteristics. RESULTS: A total of 42 patients were included (mean age, 66.7 ± 11.8 years). After a mean IOP reduction of 47.3 ± 11.9%, significant changes were observed in cup area and volume, and in rim area and volume (P < 0.01), but not in mean cup depth (P = 0.80). Multiple regression analysis (controlling for baseline IOP and magnitude of IOP reduction) showed that CH (r(2) = 0.17, P < 0.01) and diabetes diagnosis (r(2) ≥ 0.21, P < 0.01) were negatively correlated with the magnitude of changes in ONH parameters, whereas the cup-to-disc ratio was positively correlated (r(2) = 0.30, P < 0.01). Age, race, disc area, and CCT were not significant (P ≥ 0.12). Including all significant factors in a multivariable model, only the presence of diabetes remained significantly associated with all ONH parameters evaluated (P < 0.01). CONCLUSIONS: Different systemic and ocular factors, such as diabetes, CH, and the relative size of the cup, seem to be associated with the magnitude of changes in ONH topography after acute IOP reduction in POAG patients. These associations partially explain the ONH changes observed in these patients and suggest that other factors are possibly implicated in an individual susceptibility to IOP.

Assessment of water pollution in the Antuã River basin (Northwestern Portugal).

The Antuã River, located in northwestern Portugal, drains a region with a high population density and a strong economic dynamism. These factors, together with a lack of facilities for appropriate treatment of domestic and industrial sewage, are putting increasing pressure on water resources. In this context, the aim of the present study was to identify point sources of pollution and to assess the surface water quality in the Antuã basin by monitoring physicochemical variables. A total of 40 point sources of wastewater, including some with a high pollution load, were detected in the most populated and industrialized areas of the São João da Madeira and Oliveira de Azeméis municipalities. These sources explained the strong degradation of water quality observed in the upper and medium Antuã River and in one of its tributaries, where maxima of 49 mg l(-1) for biochemical oxygen demand, 29 mg l(-1) for Kjeldahl nitrogen and 3.7 mg l(-1) for total phosphorus, were found after five surface water monitoring campaigns. Despite the relevance of pollution problems, a considerable water quality improvement, promoted by favourable reaeration conditions, was observed in the final stretch of the river, giving evidence of a great self-depuration capacity. However, the Antuã is a significant contributor of nutrients to the Ria de Aveiro, the coastal lagoon where the river meets the Atlantic Ocean.

Produto FC x PAS em pacientes normo e hipertensos anestesiados com enflurano - oxido nitroso. / Heart rate x systolic blood pressure product on normotensive and hypertensive patients under enflurane-nitrous oxide anesthesia

Os autores acompanharam os valores do produto da frequencia cardiaca pela pressao arterial sistolica (FC X PAS) em 18 pacientes normotensos e 6 hipertensos submetidos a cirurgias abdominais de grande estresse sob tecnica anestesica padronizada redundancia de tiopental, oxido nitroso /oxigenio, enflurano e ventilacao controlada. Observou-se elevacao do produto imediatamente apos laringoscopia e intubacao traqueal, da ordem de 52,6% em relacao aos valores basais nos pacientes normotensos e de 36,4% nos hipertensos. Tanto num como no outro grupo, a subsequente administracao de enflurano/oxido nitroso nao so fez retornar o valor do produto aos niveis pre-inducao como ate chegou a diminui-lo significativamente em relacao a estes niveis, nos pacientes hipertensos. E ressaltada a importancia de nivel adequado de anestesia para a manutencao do produto FC X PAS proximos a seu valor basal, o que traduz variacoes minimas do consumo de oxigenio pelo miocardio (MVO2)

Observacoes sobre o uso da morfina em anestesia geral . / Use of morphine in general anesthesia

Os autores apresentam os resultados de suas observacoes sobre o emprego de doses moderadas de morfina, associada a oxido nitroso/oxigenio 50%, em vinte pacientes submetidos a cirurgias intra-abdominais eletivas. Adotou-se ventilacao controlada mecanica em todos os casos. Exceto por ligeira queda de pressao arterial media apos a injecao inicial de morfina, observou-se apreciavel estabilidade cardiovascular durante todo o procedimento. A depressao respiratoria foi constante no periodo de recuperacao pos-anestesica, da mesma forma que a analgesia residual. Seis pacientes necessitaram de ventilacao assistida ou controlada neste periodo; cuidados especiais com o ritmo respiratorio foram tomados em todos os demais. Os pacientes nao memorizavam eventos transoperatorios e isto deveu-se provavelmente, pelo menos em parte, a adicao de flunitrazepam a morfina por ocasiao da inducao. O metodo parece ser util quando se deseja evitar o emprego de agentes halogenados e/ou assegurar analgesia residual prolongada, porem exige cuidados especiais com a ventilacao no periodo de recuperacao pos-anestesica