Reducing emergency admissions and length of stay by introducing emergency surgical ambulatory service.

BACKGROUND: Emergency surgical ambulatory care provides safe and effective assessment of acute surgical referrals, in addition to reducing the pressures on hospital beds.Our aim was to look at the effect of opening a surgical ambulatory care unit (SACU) and a dedicated surgeon for the unit on length of stay and same day discharge for emergency referrals. METHODS: Data was collected prospectively and updated daily to include all referrals to SACU. Historical data was retrieved to compare the effect of introduction of SACU and dedicated surgeon on same day discharge and length of stay. RESULTS: Three groups of patients were identified: pre-SACU, SACU and SACU with dedicated surgeon. There was 104.5% percentage increase in same day discharge rate for emergency GP referrals (22% pre-SACU to 45% in the dedicated surgeon group). Similarly, same day discharge for all emergency referrals increased from 17% pre-SACU to 29% in the dedicated surgeon group.There was 25.88 h reduction in the mean length of stay for emergency GP admissions (92.95 h pre-SACU to 67.07 h in the dedicated surgeon group). In pre-SACU group mean length of stay for all emergency admissions was 125 h, this dropped to 107.09 h in the dedicated surgeon group. This resulted in 102 hospital bed stays saved every month since the opening of SACU. CONCLUSIONS: Establishing an emergency surgical ambulatory service has reduced length of stay and saved significant hospital bed stays. This effect was enhanced by having a dedicated senior surgeon providing early input and decision making.

Evaluation of the comparability of spectra generated using a tuning point protocol on twelve electrospray ionisation tandem-in-space mass spectrometers.

Product ion spectra produced by collision-induced dissociation (CID) in tandem mass spectrometry can yield important structural information on organic compounds which can aid in their identification. However, differences in experimental conditions may have a strong effect on the degree of product ion formation and therefore on the features observed in product ion spectra. For this reason, a common approach for library building is the acquisition of several spectra, typically between 5 and 10, each at a different collision energy level. In this study, the use of an alternative approach was investigated, where a tuning point protocol was applied to tune the instruments in an attempt to standardise CID conditions prior to data acquisition. With this approach, the acquisition of a single mass spectrum was sufficient. The stability of the tuning point was investigated and the choice of a commercially available search package to assess spectral comparability was discussed. Finally, the product ion spectra of 33 compounds were acquired on twelve tandem-in-space instruments, including nine triple quadrupoles, one hybrid triple quadrupole linear ion trap and two quadrupole time-of-flight mass spectrometers, resulting in 2178 spectral comparisons being carried out. The results from the spectral comparisons suggest that the use of a tuning point enables the standardisation of the experimental conditions that affect the degree of product ion formation. Indeed, 84.5% of the comparisons demonstrated a good degree of spectral agreement with match scores greater than 700, which we believe is the minimum score for a tentative library match.

Developing repeatable measurements for reliable analysis of molecules at surfaces using desorption electrospray ionization.

Desorption electrospray ionization (DESI) is a powerful ambient ionization technique that can provide high-sensitivity mass spectrometry information directly from surfaces at ambient pressure. Although a growing amount of research has been devoted to exploring different applications, there are few studies investigating the basic parameters and underpinning metrology. An understanding of these is crucial to develop DESI as the robust and reliable technique required for significant uptake by industry. In this work, we begin with a systematic study of the parameters affecting the repeatability, sensitivity, and rate of consumption of material with DESI. To do this we have developed a model sample consisting of a thin uniform film of controlled thickness of Rhodamine B on glass. This model sample allowed assessment of optimal sensitivity and spot shape under different conditions. In addition, it allowed us to study the surface in more detail to understand why and how each parameter affects these. Using the model sample to optimize the instrument parameters for DESI led to an absolute intensity repeatability of better than 15%, achieved over a period of 1 day. This model sample provides valuable insight into the electrospray-sample interaction and the desorption mechanism. Confocal microscopy of areas analyzed by DESI allow droplet distribution, material utilization, and spot size to be determined. Studying surface erosion also gives the erosion rate of material, analogous to the sputtering yield in secondary ion mass spectrometry. The results of the study provide a clear description that explains the differences observed with changing electrospray parameters allowing optimization of the technique, for both spatial resolution and sensitivity.

Cost utility of photodynamic therapy for predominantly classic neovascular age related macular degeneration.

BACKGROUND/AIM: Age related macular degeneration (AMD) is the leading cause of severe vision impairment and blindness in older people throughout the developed world and currently affects around 420 000 UK citizens. Choroidal neovascularisation (CNV) is treatable with photodynamic therapy (PDT) but is expensive at over pound 1200 per treatment. The aim of this study was to assess the cost utility of PDT for better eye, predominantly classic, subfoveal choroidal neovascular lesions secondary to AMD. METHODS: Cost utility analysis (CUA) was conducted to estimate the cost effectiveness of PDT for scenarios involving reasonable (6/12) and poor (6/60) visual acuity. The models incorporated data from the Treatment of Age-related Macular Degeneration with PDT (TAP) Study and patient based utilities. The incremental CUA was based on decision analytical models, comparing treatment to a placebo comparator. Extensive one way sensitivity analysis of parameters was conducted to determine the robustness of the model. A discount rate of 6% was used for costs and quality adjusted life years (QALY). RESULTS: Model 1: in people with reasonable initial visual acuity, the cost utility of treating applicable neovascular AMD lesions was pound 31 607 per QALY saved, with a sensitivity analysis range from pound 25 285 to pound 37 928. Model 2: in people with poor initial visual acuity, the cost utility was pound 63 214 per QALY saved, with a sensitivity analysis range from pound 54 183 to pound 75 856. CONCLUSIONS: PDT treatment is the only available treatment for some forms of neovascular ("wet") AMD. Under these assumptions, PDT can be considered moderately cost effective for those with reasonable visual acuity but less cost effective for those with initial poor visual acuity. These findings have implications for ophthalmic practice and healthcare planning.

The effect of optic disc diameter on vertical cup to disc ratio percentiles in a population based cohort: the Blue Mountains Eye Study.

OBJECTIVE: The 97.5th percentile for vertical cup to disc ratio (VCDR) has been proposed as a useful tool to assist in the diagnosis of glaucoma in population studies. Previous reports of VCDR percentiles have either not been adjusted for disc size or have been calculated by regression analysis from small hospital based cohorts. The authors' aim was to generate VCDR percentiles in a large, population based sample. METHODS: Data were collected from 3654 individuals, aged 49 years or older, living in the Blue Mountains, west of Sydney. Vertical disc diameter and VCDR were determined by planimetry from stereo optic disc photographs. The distribution of VCDR and percentiles (95th, 97.5th, 99th) were calculated. RESULTS: 6678 eyes were included in the analysis. Median cup to disc ratio, 95th, 97.5th, and 99th percentile increased with vertical optic disc diameter in a linear fashion. An increase of 0.2 in median VCDR (0.35 to 0.55) was observed between small (1.1-1.3 mm) and large (1.8-2.0 mm) optic discs. An equivalent increase of 0.2 (0.59 to 0.74) was observed for the 97.5th percentile from small to large discs. CONCLUSION: VCDR percentiles for a "normal" population, adjusted for vertical optic disc diameter are presented. One quarter of all discs fell within the small or large disc categories highlighting the importance for estimating optic disc size. These data may assist in the diagnosis of glaucoma in clinical practice as well as providing a normative database. Sole use of VCDR percentile cut offs in defining glaucoma cases in population surveys requires further validation.

Cost utility of screening and treatment for early age related macular degeneration with zinc and antioxidants.

AIM: To assess the cost effectiveness of high dose zinc and antioxidants for delaying and reducing the progression of early age related macular degeneration (AMD). BACKGROUND: AMD is the leading cause of severe vision impairment and blindness in older people throughout the developed world. It currently affects around 420 000 people in the United Kingdom. METHODS: A cost utility analysis (CUA) was conducted to estimate the cost per quality adjusted life year (QALY) for screening a cohort of men and women, aged 55 years and over, for early AMD and then treating them with zinc and antioxidants. The incremental CUA was based on a decision analytic model, comparing screening with a no screening comparator (current practice). Extensive one way sensitivity analysis of parameters was conducted to determine the robustness of the model. RESULTS: In this model the cost effectiveness of screening for early AMD was pound 22 722 per quality adjusted life year (QALY) saved. The cost per QALY decreased to pound 18 948 if photodynamic therapy with verteporfin savings were included. CONCLUSIONS: Screening for, and prophylactic treatment of, early AMD is estimated to cost around pound 22 700 per QALY saved. This cost falls within accepted levels to warrant further investigation. These findings have implications for ophthalmic practice and healthcare planning.