Importance of patient selection in evaluating a cardiac ambulance service.

All patients brought to hospital by a special cardiac ambulance were followed up and compared with patients carried by routine ambulances to assess the effectiveness of a cardiac ambulance service. The overall mortality of patients with heart attacks was 51% among those carried by an ordinary ambulance and 40% among those carried by the cardiac ambulance. The apparently low mortality in the latter group was balanced, however, by a high mortality (68%) among patients carried by ordinary ambulances when the cardiac ambulance was available but not used; these patients tended to have a short duration of symptoms and heart attacks away from home, and their ambulance was more often called by a member of the public than a general practitioner. It seems therefore that low-risk cases were inadvertently selected for transport by the cardiac ambulance; such unintentional selection makes it difficult to evaluate a cardiac ambulance service.     

Randomised trial of a mobile coronary care unit for emergency calls.

A randomised trial was conducted to assess the value of sending a mobile coronary care unit (MCCU) to all emergency calls other than those for children or for patients injured in road-traffic accidents or brawls. Over 15 months 6223 calls for emergency ambulances were considered for the study, but a routine ambulance had to be dispatched on 2583 occasions because the MCCU was not available. A group of 1664 patients was randomly allocated to transport by the MCCU and 1676 patients to routine transport. In these groups the prehospital mortality among patients with heart attacks was 45% and 47%, and no patient survived resuscitation attempts long enough to leave hospital. During the same period general practitioners sent 190 patients with heart attacks to hospital in routine ambulances and none of them died during the interval between the call for the ambulance and arrival at hospital. Although it may be worth equipping all emergency ambulances with a defibrillator, MCCUs as at present envisaged will not appreciably affect mortality from heart attacks.     

Use of the automatic external defibrillator-pacemaker by ambulance personnel: the Stockport experience.

In an attempt to reduce the number of people who die from a cardiac arrest in the Stockport area ambulances were equipped with automatic external defibrillator-pacemakers, and ambulance personnel were trained in their use. Over an 18 month period ambulance personnel attended 113 patients in cardiac arrest with these devices. One patient subsequently survived, and three patients survived for up to three days. The reasons for these poor initial results include the failure of bystanders to provide cardiopulmonary resuscitation, a delay in calling for the ambulance, and too few defibrillators being available.     

The Brighton resuscitation ambulances: a continuing experiment in prehospital care by ambulance staff.

Two ambulances from the existing fleet in Brighton and one in Hove are equipped with portable defibrillator-oscilloscope units. Selected attendants have been trained not only to defibrillate patients but also to perform endotracheal intubation and administer intravenous atropine and lignocaine for carefully defined indications. In the two years up to December 1975 the ambulances responded to 2253 calls which were considered possible emergencies. Retrospective analysis showed that half of these had been for patients with myocardial infarction, coronary insufficiency, or angina. The ambulances took a median time of five minutes to reach a patient. Attempts at resuscitation were made in 207 patients with circulatory arrest, of whom 160 had ventricular fibrillation. Coordinated rhythm was restored at least transiently in 66 patients, and 27 of them survived to leave hospital. Sixteen of the survivors had been in ventricular fibrillation before the arrival of the ambulance. The delay before admission to hospital was reduced: over 50% of patients carried in the ambulances were admitted within two hours of the onset of major symptoms. No extra ambulance staff have been employed for the scheme. The increased load on hospital services has been limited by encouraging a rational admission policy and also by early discharge.     

General practitioner attendance at emergencies notified to ambulance control.

For two years doctors from a small village went to the scene of emergency calls received by ambulance control. On 80% of the occasions when the doctor was called at the same time as the ambulance was dispatched the doctor arrived before the ambulance. There were 24 incidents, 16 of which were road traffic accidents. In two cases the doctor established a clear airway in an unconscious patient before the ambulance arrived. Two patients were trapped in their vehicles and were given parenteral analgesics. Four patients required intravenous fluids. The call out system provided first aid for patients before the ambulance arrived and medical assistance to the emergency services at serious accidents. Patients who did not require hospital attention could be examined and treated at the scene, making the ambulance available for other duties and reducing the number of patients taken to the hospital accident and emergency department.     

Simple training programme for ambulance personnel in the management of cardiac arrest in the community.

The extended training for ambulance personnel in Nottinghamshire includes a period of training in cardiac resuscitation by defibrillation, and defibrillators are now part of the standard equipment of vehicles used on the accident and emergency service. Comparison of recent results with previous attempts in the City of Nottingham to provide a service for out of hospital cardiac arrest has shown that an elementary training course and the provision of defibrillators on emergency vehicles enables the ambulance service to save the lives of a reasonable proportion of those who suffer sudden death in the community. The extended training programme as a whole has proved acceptable to ambulance personnel and we believe that this programme could be the basis for a more widespread introduction of post basic training.     

Pre-hospital Coronary Care Service

The Dublin cardiac ambulance service operates two specially-equipped ambulances from a private ambulance station; five metropolitan hospitals provide coronary care beds on a rota system. The service covers an area of 450 square miles (1,165 sq km) and a population of 800,000. The ambulances are staffed solely by trained ambulance personnel. During the first three years 1,973 patients were transported to hospital. Primary ventricular fibrillation was encountered in 20 patients and successfully treated in 17. No deaths occurred in the ambulance.Over 98% of the patients were transferred uneventfully to hospital, so a medical team from the hospital on duty was called on 30 occasions only. A feature of the Dublin service is the low cost of a standard ambulance call, at about £7·50.     

Ambulance ride: fixed or floating stretcher?

The alternatives of a purpose-bult ambulance and a specially designed stretcher suspension system were considered and the features of the latter assessed by subjective and objective tests. The results showed a significant improvement in the quality of the ride offered to the patient.     

Advanced training for ambulance crews: implications from 403 consecutive patients with cardiac arrest managed by crews with simple training.

Sixty seven ambulance staff in Nottinghamshire completed a simple extended training programme in managing cardiac arrest and using a defibrillator. This enabled around one third of the ambulance emergency shifts to be manned by such a crew, with a defibrillator as part of their standard equipment. Forty four of 403 consecutive patients who suffered cardiac arrest in the community were managed by these crews and survived to leave hospital. The training programme does not include endotracheal intubation, intravenous infusion, or drug administration. The new official advanced training course for ambulance crews, which includes these skills, is inappropriate in its methods and may delay widespread introduction of emergency ambulances equipped with defibrillators.     

Construction of Retroviral Vectors with Improved Safety, Gene Expression, and Versatility

Murine leukemia virus (MLV)-based retroviral vectors are the most frequently used gene delivery vehicles. However, the current vectors are still not fully optimized for gene expression and viral titer, and many genetic and biochemical features of MLV-based vectors are poorly understood. We have previously reported that the retroviral vector MFG, where the gene of interest is expressed as a spliced mRNA, is superior in the level of gene expression with respect to other vectors compared in the study. As one approach to developing improved retroviral vectors, we have systematically performed mutational analysis of the MFG retroviral vector. We demonstrated that the entire gag coding sequence, together with the immediate upstream region, could be deleted without significantly affecting viral packaging or gene expression. To our knowledge, this region is included in all currently available retroviral vectors. In addition, almost the entire U3 region could be replaced with the heterologous human cytomegalovirus immediately-early promoter without deleterious effects. We could also insert internal ribosome entry sites (IRES) and multicloning sites into MFG without adverse effects. Based on these observations, we have constructed a series of new, improved retroviral constructs. These vectors produced viral titers comparable to MFG, expressed high levels of gene expression, and stably transferred genes to the target cells. Our vectors are more convenient to use because of the presence of multicloning sites and IRESs, and they are also more versatile because they can be readily converted to various applications. Our results have general implications regarding the design and development of improved retroviral vectors for gene therapy.     

Animal reactions to oncoming vehicles: a conceptual review

Animal–vehicle collisions (AVCs) are a substantial problem in a human‐dominated world, but little is known about what goes wrong, from the animal's perspective, when a collision occurs with an automobile, boat, or aircraft. Our goal is to provide insight into reactions of animals to oncoming vehicles when collisions might be imminent. Avoiding a collision requires successful vehicle detection, threat assessment, and evasive behaviour; failures can occur at any of these stages. Vehicle detection seems fairly straightforward in many cases, but depends critically on the sensory capabilities of a given species. Sensory mechanisms for detection of collisions (looming detectors) may be overwhelmed by vehicle speed. Distractions are a likely problem in vehicle detection, but have not been clearly demonstrated in any system beyond human pedestrians. Many animals likely perceive moving vehicles as non‐threatening, and may generally be habituated to their presence. Slow or minimal threat assessment is thus a likely failure point in many AVCs, but this is not uniformly evident. Animals generally initiate evasive behaviour when a collision appears imminent, usually employing some aspect of native antipredator behaviour. Across taxa, animals exhibit a variety of behaviours when confronted with oncoming vehicles. Among marine mammals, right whales Eubalaena spp., manatees Trichechus spp., and dugongs Dugong dugon are fairly unresponsive to approaching vehicles, suggesting a problem in threat assessment. Others, such as dolphins Delphinidae, assess vehicle approach at distance. Little work has been conducted on the behavioural aspects of AVCs involving large mammals and automobiles, despite their prevalence. Available observations suggest that birds do not usually treat flying aircraft as a major threat, often allowing close approach before taking evasive action, as they might in response to natural predators. Inappropriate antipredator behaviour (often involving immobility) is a major source of AVCs in amphibians and terrestrial reptiles. Much behavioural work on AVCs remains to be done across a wide variety of taxa. Such work should provide broad phylogenetic generalizations regarding AVCs and insights into managing AVCs.     

Osmolarity of osmium tetroxide and glutaraldehyde fixatives

Synopsis The evidence available to date for the importance of fixative osmolarity is considered together with some observations on the volume changes of crab axons after fixation by osmium tetroxide and glutaraldehyde. The results obtained are compared with those obtained from crab axons and from amphioxus skin cells which had been processed and examined with the electron microscope after initial fixation in fixatives of different composition. It is concluded that the osmolarity of the fixative vehicle is of considerable importance when the fixing agent is glutaraldehyde but is of less importance when the fixing agent is osmium tetroxide or a mixture of the two agents.Preliminary observations upon crab axons fixed with glutaraldehyde in a vehicle approximating to the internal composition of the cells suggest that this approach to the design of fixative vehicles may be useful.     

Mobile Coronary Care Provided by Ambulance Personnel

Mobile coronary care has been provided in Brighton by ambulance personnel without immediate help from physicians or nurses. No additional vehicles or staff were required. The capital cost of the experiment was therefore small and additional running costs were negligible. The results have been monitored by retrospective analysis of electrocardiograms recorded in the ambulance and stored on magnetic tape. In the first 12 months of operation to July 1972, 1,082 patients with suspected cardiac emergencies were carried in two vehicles. Subsequent analysis showed that 76% of these patients had acute symptoms from ischaemic heart disease or had circulatory arrest. Eighty-six per cent. of arrhythmias were diagnosed correctly by the ambulance attendants. Though only eight cases of primary ventricular fibrillation occurred during or shortly before transit all were successfully reversed, and five of these patients subsequently left hospital alive. Other benefits of the scheme have included an appreciable reduction in the median delay between onset of presenting symptoms in patients with acute myocardial ischaemia and their admission to hospital.     

Alien and native plant seed dispersal by vehicles

Vehicles play a significant role in spreading plants, both in terms of quantity and quality (species). This study was conducted in Southeast Queensland to determine the role of utility vehicles in spreading seeds. These vehicles were found to carry up to 397 seeds per vehicle and in all four seasons of the year, with the majority of these species being alien to Australia and/or Queensland. The largest seed loads were found in autumn in this summer rainfall environment. Seeds were shown to attach to all parts of the vehicle, often in mud picked up from the ground, affixed directly to the engine or radiator, or carried into the cabin by the driver. Therefore, much of the seed load is to be found on the underside, on the back and front mudguards while smaller collections were found in the cabin, on the radiator and engine, and on the tyres. Fewer viable seeds were found on the engine, presumably as desiccation and heat contributed more to their death on this part of the vehicle. One method used to reduce weed seed spread by vehicles in Queensland is washing and vacuuming of vehicles. From the present study, these procedures would need to be applied to all parts of the vehicle and in all seasons of the year.     

Commercialization of Lithium Battery Technologies for Electric Vehicles

The currently commercialized lithium‐ion batteries have allowed for the creation of practical electric vehicles, simultaneously satisfying many stringent milestones in energy density, lifetime, safety, power, and cost requirements of the electric vehicle economy. The next wave of consumer electric vehicles is just around the corner. Although widely adopted in the vehicle market, lithium‐ion batteries still require further development to sustain their dominating roles among competitors. In this review, the authors survey the state‐of‐the‐art active electrode materials and cell chemistries for automotive batteries. The performance, production, and cost are included. The advances and challenges in the lithium‐ion battery economy from the material design to the cell and the battery packs fitting the rapid developing automotive market are discussed in detail. Also, new technologies of promising battery chemistries are comprehensively evaluated for their potential to satisfy the targets of future electric vehicles.     

Use of Entonox in the Ambulance Service

An analgesic mixture of nitrous oxide and oxygen (Entonox) has been used in nine ambulances in Gloucestershire for self-administration by patients in severe pain. Over a period of three and a half months 66 patients have been treated. In all cases the pain was wholly or partially relieved, and in no instance was the patient''s condition worsened. No undesirable side-effects attributable to Entonox were produced. It is recommended that other ambulance authorities should consider the use of Entonox in this context.     

Evaluation of Publicly Financed and Privately Delivered Model of Emergency Referral Services for Maternal and Child Health Care in India

Background

Emergency referral services (ERS) are being strengthened in India to improve access for institutional delivery. We evaluated a publicly financed and privately delivered model of ERS in Punjab state, India, to assess its extent and pattern of utilization, impact on institutional delivery, quality and unit cost.

Methods

Data for almost 0.4 million calls received from April 2012 to March 2013 was analysed to assess the extent and pattern of utilization. Segmented linear regression was used to analyse month-wise data on number of institutional deliveries in public sector health facilities from 2008 to 2013. We inspected ambulances in 2 districts against the Basic Life Support (BLS) standards. Timeliness of ERS was assessed for determining quality. Finally, we computed economic cost of implementing ERS from a health system perspective.

Results

On an average, an ambulance transported 3–4 patients per day. Poor and those farther away from the health facility had a higher likelihood of using the ambulance. Although the ERS had an abrupt positive effect on increasing the institutional deliveries in the unadjusted model, there was no effect on institutional delivery after adjustment for autocorrelation. Cost of operating the ambulance service was INR 1361 (USD 22.7) per patient transported or INR 21 (USD 0.35) per km travelled.

Conclusion

Emergency referral services in Punjab did not result in a significant change in public sector institutional deliveries. This could be due to high baseline coverage of institutional delivery and low barriers to physical access. Choice of interventions for reduction in Maternal Mortality Ratio (MMR) should be context-specific to have high value for resources spent. The ERS in Punjab needs improvement in terms of quality and reduction of cost to health system.     

Local vehicles add nitrogen to moss biomonitors in a low-traffic protected wilderness area as revealed by a long-term isotope study

Public use of protected areas is typically encouraged, but visitors arriving by vehicles may alter the natural areas they seek. Vehicle emissions add nitrogen oxides (NO_x) and ammonia (NH₃) to the air, which can increase the amount of plant-available (reactive) nitrogen, a limiting nutrient. Changes in ecosystem processes as a result of increases in nitrogen availability are at odds with the goals of many protected wilderness areas that are typically accessed by vehicles. In this multi-year study (2003–2019), we tested whether emissions from local vehicles entered the forest ecosystem adjacent to a highway in a protected wilderness valley near a mid-sized city (Calgary, Alberta, Canada). We examined the concentration of NO₂ in the air and the abundance of combustion-derived nitrogen isotopes (δ¹⁵N) in naturally-occurring forest moss (Hylocomium splendens and Pleurozium schreberi) within 20 m of the highway as a function of traffic levels that varied independently at two scales: along the highway and among years. Within the valley, we observed a gradient in the number of vehicles that was greatest where vehicles enter the valley, with a corresponding pattern for NO₂ concentrations in air. Traffic volume also varied among years, with the highest year having almost twice as many vehicles in the summer as the lowest year. δ¹⁵N values in forest moss displayed similar patterns as traffic both within and among years, signalling that nitrogen from vehicle emissions entered the local ecosystem corresponding to local traffic levels. Because vehicle emissions enter natural ecosystems that are intended to be conserved, vehicle use must be considered in the management of protected natural areas.     

Greenhouse Gas Emissions Payback for Lightweighted Vehicles Using Aluminum and High‐Strength Steel

In this article we consider interactions between life cycle emissions and materials flows associated with lightweighting (LW) automobiles. Both aluminum and high‐strength steel (HSS) lightweighting are considered, with LW ranging from 6% to 23% on the basis of literature references and input from industry experts. We compare the increase in greenhouse gas (GHG) emissions associated with producing lightweight vehicles with the saved emissions during vehicle use. This yields a calculation of how many years of vehicle use are required to offset the added GHG emissions from the production stage. Payback periods for HSS are shorter than for aluminum. Nevertheless, achieving significant LW with HSS comparable to aluminum‐intensive vehicles requires not only material substitution but also the achievement of secondary LW by downsizing of other vehicle components in addition to the vehicle structure. GHG savings for aluminum LW varies strongly with location where the aluminum is produced and whether secondary aluminum can be utilized instead of primary. HSS is less sensitive to these parameters. In principle, payback times for vehicles lightweighted with aluminum can be shortened by closed‐loop recycling of wrought aluminum (i.e., use of secondary wrought aluminum). Over a 15‐year time horizon, however, it is unlikely that this could significantly reduce emissions from the automotive industry, given the challenges involved with enabling a closed‐loop aluminum infrastructure without downcycling automotive body structures.     

A finite element model of an anthropomorphic test device lower limb to assess risk of injuries during vertical accelerative loading

Improvised explosive devices (IEDs) were used extensively to target occupants of military vehicles during the conflicts in Iraq and Afghanistan (2003–2011). War fighters exposed to an IED attack were highly susceptible to lower limb injuries. To appropriately assess vehicle safety and make informed improvements to vehicle design, a novel Anthropomorphic Test Device (ATD), called the Warrior Injury Assessment Manikin (WIAMan), was designed for vertical loading. The main objective of this study was to develop and validate a Finite Element (FE) model of the WIAMan lower limb (WIAMan-LL). Appropriate materials and contacts were applied to realistically model the physical dummy. Validation of the model was conducted based on experiments performed on two different test rigs designed to simulate the vertical loading experienced during an under-vehicle explosion. Additionally, a preliminary evaluation of the WIAMan and Hybrid-III test devices was performed by comparing force responses to post-mortem human surrogate (PMHS) corridors. The knee axial force recorded by the WIAMan-LL when struck on the plantar surface of the foot (2 m/s) fell mostly within the PMHS corridor, but the corresponding data predicted by the Hybrid-III was almost 60% higher. Overall, good agreements were observed between the WIAMan-LL FE predictions and experiments at various pre-impact speeds ranging from 2 m/s up to 5.8 m/s. Results of the FE model were backed by mean objective rating scores of 0.67–0.76 which support its accuracy relative to the physical lower limb dummy. The observations and objective rating scores show the model is validated within the experimental loading conditions. These results indicate the model can be used in numerical studies related to possible dummy design improvements once additional PMHS data is available. The numerical lower limb is currently incorporated into a whole body model that will be used to evaluate the vehicle design for underbody blast protection.