RESUMO
OBJECTIVE: To present a new concept for the extinguishment of wildfires by saturation water bombing. DESIGN: Following an exhaustive literature search, a published mathematical model and a published empirical rainfall model were used to estimate the rate at which water would have to be applied to extinguish intense wildfires. Applying the estimated amount by quasi-continuous saturation water bombing was then evaluated. RESULTS: The mathematical model yielded a regression equation that estimates the amount of water to extinguish wildfires of varying sizes as y = 0.1041 x - 5.0096 where y is the quantity of water and x is the size of the fire. The predicted quantities of 1000 metric tonnes ha for intense wildfires vastly exceed the minimum of 50 metric tonnes ha of the empirical rain model, likely due to the limited data available. They nevertheless serve to define the likely range of water application rates that must be applied for wildfire extinguishment. These application rates are shown to be feasible by deploying a team of large, amphibious water scooping aircraft operating in relay continuously day and night. The operating cost of such a team (±$10 million annually) is trivial compared to the potential for reducing the current economic burden of US wildfire of $71.1-347.8 billion annually. CONCLUSIONS: The saturation water bombing concept seems promising enough to warrant the commitment of funds to implement field trials on the ground that it could, potentially, result in savings of billions of dollars.
Assuntos
Incêndios , Incêndios Florestais , Humanos , Modelos Teóricos , ÁguaRESUMO
A 48-year old Caucasian woman presented with chest pain on exertion and was diagnosed with an anomalous origin of dominant right coronary artery, it then ran a short intramural course in the wall of the aorta. Right coronary artery (RCA) was reimplanted on cardiac bypass at normal exit point on the aortic root. The heart was adequately protected with antegrade cold blood cardioplegia via the aortic root and regular direct cardioplegia via the coronary ostia. The patient could not come off cardiopulmonary bypass after surgery and required right ventricular assist device support to be weaned from cardiopulmonary bypass. The patient ultimately recovered well and her right heart function is normalising. We believe that antegrade cardioplegia via the aortic root caused increased pressure in the aorta and squashed RCA in the wall of the aorta causing failure of myocardial protection and stunning of the right ventricle. This could be prevented with alternative myocardial protection strategies like direct cardioplegia via the coronary ostium.
Assuntos
Aorta Torácica , Anomalias dos Vasos Coronários/complicações , Anomalias dos Vasos Coronários/cirurgia , Parada Cardíaca Induzida/métodos , Feminino , Humanos , Pessoa de Meia-IdadeRESUMO
BACKGROUND: NSAIDs are commonly used analgesic agents in the orthopaedic trauma setting. Evidence-based guidelines recommend that patients with one or more risk factors for NSAID-associated gastrointestinal (GI) ulcer complications should be prescribed gastroprotective agents to minimise the risk of serious ulcer complications, including gastrointestinal haemorrhage. The purpose of the present audit was to evaluate and improve the adherence to these guidelines in new-NSAID users in a trauma unit at a district general hospital. METHODS: A retrospective observational cohort study was conducted over an 18-week period to assess pre-intervention practice. Subsequently, an awareness programme, including prescriber and pharmacist education and the use of reminder posters, was implemented. Following this, data were collected prospectively over 9 weeks to assess any change in performance. Assessment involved review of case-notes and prescription charts of all adults (aged ≥ 18 years) who were commenced on regular NSAIDs on or during admission to the Trauma Unit. Patients were risk-stratified according to the number of risk factors, which were defined as age ≥ 65 years, major comorbidity, oral steroids, anticoagulation, history of upper gastrointestinal ulceration or bleeding and prescription above the normal recommended dose of NSAIDs. The American College of Rheumatology guidelines recommend the use of gastroprotective agents when one or more risk factors was present. Prescription of gastroprotective drugs was recorded to measure adherence to evidence-based guidelines. RESULTS: A total of 644 patients were reviewed over the study period, 451 pre-intervention and 193 post-intervention. 100 patients fulfilled the inclusion criteria pre-intervention and 49 post-intervention. Before intervention, the proportion of high-risk NSAID-receivers co-prescribed gastroprotection was low at 25.3%, although the likelihood of adherence improved with the number of risk factors; overall adherence rate improved significantly following intervention at 73.1% (chi² = 18.8, p < 0.001). Furthermore, a smaller proportion of NSAID-receivers fell into the high-risk category from 75% to 56.5% (chi² = 7.25, p < 0.05). CONCLUSIONS: (1) The majority of trauma admissions are at high risk for developing gastrointestinal haemorrhage. (2) Initial adherence to national guidelines for safe prescription of NSAIDs in our trauma unit was poor (25.3%) but improved significantly (73.1%) following an awareness programme which included education of prescribers and pharmacists. (3) A lower proportion of NSAID-receivers had multiple risk factors following our awareness programme. (4) Awareness of gastroprotection guidelines must be raised in trauma units to prevent undertreatment and hence minimise the risk of GI haemorrhage.