Over the past several decades, ambulance services have evolved from a basic service of transporting patients to hospitals to a comprehensive emergency medical service provider of advanced care for both life-threatening and non-life-threatening conditions outside the hospital setting [1, 2]. During this period, the demand for ambulance services has increased in most industrialized nations due to demographic changes, shifting social support structures, access problems, and economic pressures. The changes have brought a series of increased pressures on EDs, ambulance services, and the general healthcare system. These might make the service compromising on the safety of the patients, quality of treatment, and accessibility. Also, there has been frequent overcrowding in emergency departments, which has become a common issue [3].

Care for ambulance patients has changed over the years, which has also seen more general change and advancement in health care technology, education, and medical practice. In the early days of operation, the main contribution or service that ambulances offered was simply to transport people to the hospital; during transport, little medical care was administered [4]. With advances in medical science and technology, so has evolved the role of the ambulance to include prehospital care, basically turning these vehicles into mobile medical units that bring critical care to the scene [5]. Advanced life support (ALS) systems are one of the major shifts in care from the ambulance. Advances in this area have put paramedics in a position to intubate, defibrillate, inject intravenous drugs, and do many other complex medical procedures far ahead of the patient's arrival at a hospital. It is this capability that can be very important in emergency situations where timely intervention may make a difference between life and death, such as in cardiac arrest, severe trauma, or respiratory failure [6].

In the broader framework of emergency medical services, the process of an ambulance is a significant element in line with the consistent conveyance of patients to an emergency department or any other health facility [7]. However, in many cases, patients do not need to be conveyed. Conveyance refers to the process by which patients along with medics, equipment required, and documents related to the patients' case are transferred either from the scene to a health facility or between health institutions [8]. However, non-conveyance relates to certain incidents in which, following treatment and/or assessment in a location away from a hospital, a patient does not need to be transferred to treatment in a care-giving facility [9, 10]. In such a case, the treatment or care might be delivered there, at the scene of the incidence, when it becomes enough for the patients to be discharged, or they are referred on to other healthcare services, such as a general practitioner. Non-conveyance can be broadly classified into two types: the patient's refusal of transportation and the judgment by ambulance professionals that conveyance is not necessary. Quite often, both combine in these situations: patient preference and professional judgment [11-13]. This review aims to analyze the role of ambulances in patient care, with insights into the advancements, challenges, and prospects.

With rapid developments in the field of technology, the emergency services, especially the ambulances, have gone through an extensive revolution. These rapidly improving factors are the reasons behind the competent performance of emergency teams in providing immediate and quality care to a patient before his or her admission to the hospital. Advanced medical equipment and the installation of good communication systems in an ambulance have been cornerstones for progress in pre-hospital care [14]. One of the most striking technological advances is the implementation of highly sophisticated diagnostic facilities in an ambulance. These devices include portable electrocardiograms, which can closely monitor in real time the functioning of a patient's heart and even diagnose cardiac conditions, such as a myocardial infarction, prior to hospital admission [15]. Besides, other high-level imaging, such as portable ultrasound machines, enables the paramedics to examine injuries of an internal nature at a scene and helps them in decisions concerning immediate care [16, 17].

Putting aside the more diagnostic machinery, modern ambulances can find a place for a variety of sophisticated lifesaving machinery. Among these are automatic external defibrillators and advanced ventilators, finding their places as standard equipment in many ambulances. These have been able to rapidly stabilize patients suffering from cardiac arrest or respiratory failure, tremendously increasing survival rates [18]. Additionally, telemedicine integrated into ambulances will help paramedics liaison directly with hospital-based specialists to ensure the care delivered on the way to the hospital is the most appropriate and current medical guidelines addressing the unique needs of the patient [19].

Advanced Life Support (ALS) Ambulances

Advanced life support (ALS) ambulances changed the face of the emergency medical service. ALS ambulances are specially designed and equipped to treat and handle serious and life-threatening medical conditions. Unlike the Basic Life Support units that only have care limited to CPR, bleeding control, and very basic airway management, an ALS has paramedics who are highly trained and capable of doing complex medical procedures on patients [20]. ALS ambulances are outfitted with advanced medical equipment to allow comprehensive patient care in the field. This might involve the presence of monitors, defibrillators, IV setups, and other airway management tools like endotracheal tubes. Having these tools available means that medications can be administered, intubations can be performed, and other critical interventions executed that sometimes stabilize a patient for transport [21].

Besides, ALS ambulances bridge the gap between on-scene care and in-hospital treatment. And above all, ALS crews will be trained on ALS units to interpret complex medical information, make quick clinical decisions, and implement treatment protocols formerly possible only in a hospital setting [15]. For example, a patient in crisis from an acute asthmatic attack—ALS paramedics can use a bronchodilator and corticosteroids to manage the airway and perform field oxygen therapy en route to the hospital [22]. ALS ambulances have dramatically changed the outcomes for patients in rural or remote areas where access to a hospital might be immediate. The ability to deliver advanced care in the field reduces the time to treatment, which is a critical element in any medical emergency. ALS interventions have clearly been shown to dramatically reduce mortality and morbidity rates with cardiac arrest, stroke, and trauma [23].

Professionals like paramedics and emergency medical technicians are the backbones of any efficient and modern ambulance service. These people are well-equipped with intensive training to make a response to most kinds of medical emergencies, from simple injuries to critical conditions. It is through them that proper pre-hospital care is offered, which may significantly affect the outcome in patients [24]. While it is true that both paramedics and EMTs are well-trained, the former has more advanced training and a wider scope of practice compared to the latter. The former gets basic training to perform emergency care skills. Some of their duties include performing or conducting BLS. This provides basic emergency care such as CPR, bleeding control, splinting, and assisting in childbirth [25]. They also learn the basic ways to check a patient for their present condition, measure vital signs, and give attention to respiratory and cardiac crises by non-invasive methods [26].

On the other hand, paramedics receive higher-level training, which normally includes college coursework and clinical internships. This enables them to perform advanced life-support interventions that are very important during higher-level medical emergencies [20, 27]. Advanced airway management training involves intubation, medications administered via the intravenous route, electrocardiogram interpretation, and management of complex trauma. Their expanded scope of practice gives them the ability to make critical decisions at the scene, which may stabilize patients prior to arrival in a hospital [28].

Some of the key roles of a paramedic and an EMT are on-scene assessment and care of the patient. In the case of EMTs, treatment usually includes basic life-support care by way of administering oxygen therapy, dressing wounds, and immobilizing injured extremities [29]. Their services have also been sought in maintaining the airway of the patient and in providing them with ventilation via simple devices such as a bag-valve mask. The other primary role of EMTs and paramedics is to safely yet efficiently transport patients to the hospital. The latter also ensure that the patient remains stabilized on the way, keeping a constant eye on vital signs and performing interventions whenever necessary to maintain, even improve the condition of the patient [30]. In particular, paramedics are educated and trained to deal with highly complex and sophisticated medical equipment and medications used during transportation, which often proves quite vital in keeping patients stable over large distances or where admission to a hospital is delayed [31].

The role of the paramedic and EMT is very vital to the patient's outcomes, especially in time-critical medical emergencies. Interventions they provide during this most critical period of pre-hospital phase will literally make the difference between life and death, in particular from cardiac arrest, stroke, or severe trauma. It has been shown that survival rates and long-term impact of injuries and illnesses are drastically improved by early intervention by trained EMS personnel.

EMS responders are, by nature, the first providers of health care at scenes of disasters and provide critical prehospital care. They quite often happen to be the first to identify the type and magnitude of disasters, whereby they make quick assessments at the scene to judge the need for additional resources, especially medical aid [10]. Crisis standards of care (CSC) will have to be performed by persons who are licensed or certified as emergency medical dispatchers or responders or as emergency medical technicians or paramedics. They form a critical partnership in the development but also in the implementation of coordinated CSC plans at local and state levels [32, 33]. EMS response in various conditions like conventional, contingency and crisis are shown in Table 1.

Where resources are constrained - for instance medical personnel, supplies, equipment, fuel, or medications are in reduced quantities, mutual aid is limited, and communication as well as coordination is disrupted - emergency health care has to adapt [34]. However, the strategic application and planning for resource management is crucial in such scenarios. This will involve fully using every available personnel, activating community response teams and health care registries, using disaster triage protocols, and changing how patients are transported or where patients are transported to. These adaptations are made to facilitate the best use of available resources when extending care to any number of sufferers even under tough conditions [35].

Table 1. A brief description of EMS response in different conditions like conventional, contingency and crisis.

Disaster Care: Prehospital care can be significantly different in times of disasters. The changeability may involve the scope of practice for EMS personnel to further extend their roles to perform, say, vaccination or other medical procedures after receiving just-in-time training. The EMS teams can also function in non-traditional environments like shelters, alternate care sites, patient receiving centers, clinics, and even temporary medical units in tented areas [40]. This could include altering customary practice by reducing the ambulance staff to a driver and one medical attendant, using alternate modes of transportation such as a van or bus, or treat-and-release with no hospital transportation in these scenarios [41].

They can also be required to assist with the evacuation of patients from health care facilities to other locations for continuation of care, which would involve extended periods of care beyond the normal role of the EMT, whose usual work is limited to initial stabilization of patients at the scene and during transport [42]. These adaptations should be checked and approved by medical EMS directors at all levels—state, regional, and local—to ensure their effectiveness and congruency with CSC protocols and procedures developed at the state level. For instance, one protocol developed in Maryland offered a framework for EMS providers to follow during a catastrophic public health incident [43].

Those strategies include use of a triage screening algorithm to appropriately focus resources on the most critically ill or injured patients; use of principles for withholding or withdrawing life-sustaining interventions; using scarce medical equipment only if a patient meets very rigorous criteria; restricted transport; and preservation of access to the emergency department only for those patients with immediately life-threatening conditions [44]. These procedures are instigated and implemented to ensure the maximum utilization of available limited resources and prioritizing of needs in cases where matters are overwhelmingly insatiable. Following such protocols, the EMS people could do the best in their capacity to care for patients, given the adversarial conditions of a disaster, and help as many persons as possible with the available facilities [45].

Figure 1 shows the stages of pre-hospital EMS in the continuum of care.

Figure 1. Phases of the continuum of treatment for pre-hospital emergency medical services

Considering the respective applications in pre-hospital EMS, the below-mentioned clusters of ambulance technologies have been reported [46].

Cluster I (Intelligent Transportation System): Ambulance technologies in this cluster include those that deal with location identification, access and control, dispatching, design, and the quickest path to the closest hospitals. Thus, the technologies in this cluster can contribute to reducing death and disability as well as helping to achieve the eight-minute EMS response time [47-50].

Cluster II (eHealth): The information and communication technologies associated with ambulances that can enhance patient monitoring, care, diagnosis, and prevention are included in this cluster. The medical staff at the hospital emergency room and the patients inside the ambulance can exchange information thanks to technologies in this cluster [51]. Furthermore, telehealth, telemedicine, and eHealth technologies are all included in eHealth. By exchanging vital information that helps emergency physicians prepare for patient arrival, this cluster can raise the survival rate [52].

Cluster III (Telecommunication Infrastructure): The technologies in this cluster enable and secure communication via the internet and other channels in the intelligent transport system and e-Health during pre-hospital emergency medical services.

As a result, internet data may move over several media, including satellites and fiber-optic cables, with efficiency. Furthermore, without the evolution of technology in this cluster, ambulance technologies in the previous two clusters cannot function as intended. In addition, new technologies like 5G have the potential to completely change the way the EMS functions in smart cities [53, 54]. These clusters have been summarized under Table 2.

Table 2. A summarised version of the key points of the above-mentioned clusters of emergency services.

Response Time and Accessibility

When it comes to providing emergency medical services, ambulance-based patient care is a vital and frequently time-sensitive service. It is extremely difficult to achieve quick and reliable response times in any scenario because of a variety of issues, the most significant of which are related to the infrastructure and geographic disparities between urban and rural locations [55]. Optimal EMS response times usually face hard challenges in urban environments due to high human density and complex infrastructure. Traffic, high congestion, narrow streets, and limited access routes are common regular delayers of advanced life support response times to emergency scenes. The high-rise buildings and densely populated areas may add to the complexity of accessing the patients, especially when there is no elevator or when access has to be made to different floors [56].

Urban areas are subject to the constant roadblocks of construction, parades, and other public events that make ambulances reroute and arrive much later than their predicted times. Cities generally have better expectations in terms of the availability of EMS-hospitals and ambulance stations-but the sheer number of emergency calls can tax those resources, resulting in variable response times [57, 58]. These peak time calls, public gatherings, or rush hour situations can create a larger demand than what is available in terms of resources, therefore increasing further delays in delivering the service. However, rural areas have a completely different set of issues in terms of the response times of ambulances. One of these pertains to the geographic dispersion whereby the setting can be made up of large separations between communities [59]. Sufficiently, in most of the remote rural areas, there are a few ambulances that may keep the EMS personnel traveling for quite a long distance. The dirt roads without any sign and narrow lanes, common to many rural areas, may further cause delay in the arrival of emergency personnel [60].

Moreover, after reaching the patients, many ambulances have to cover long distances due to the scarcity of health facilities in rural areas. This transportation time can easily become critical for a patient in serious life-threatening conditions that require immediate medical attention. The remote areas are even more inaccessible during seasons, such as snowfall in winters and floods in spring, which makes it hard for ambulances to reach patients quickly. This calls for tailored measures to handle the different levels of response time for the ambulances between the cities and the countryside. In city setups, the design of a traffic management system relies on the system, that is likely to play a two-way role, for instance, as a lane for buses only, which when the need arises can let ambulances travel the opposite way as a response to do deal with crisis situations for either side of the road. The addition of more ambulance stations in better strategic locations, on the other hand coupled with more sophisticated algorithm that is keyed on the closest random unit can, in absolute terms, increase efficiency of more in response [61].

It involves building EMS infrastructures, such as increasing the number of ambulance stations and building, or improving, the road network in rural settings. Other ways include enhancing community-based emergency response systems, and that can be achieved through training local volunteers or first responders for providing initial care until the arrival of an ambulance [62-64]. The use of air ambulances in the most inaccessible or isolated terrains reduces the time it would generally take to transport patients to more sophisticated care canters [65]. Innovations such as telemedicine could be useful in both urban and rural contexts, enabling EMS to consult with in-hospital specialists while the patient is on the way. This would initiate critical care while transportation is ongoing and improve overall outcomes despite delays [66, 67].

Resource Limitations

Probably one of the most major resource limitations in care based within ambulances is that of trained EMS personnel. Supply of EMS professionals usually lag behind the demand for these personnel, with much higher needs, especially in rural and underserved areas [68]. This may lead to delays in response times because the available staff has to be spread out, usually over larger geographic areas or for extended shifts. Apart from the instances of large-scale emergencies where the number of patients is higher than the total workforce, this shortage of staff affects the ability of the services to provide timely sufficient care even in the event of mass casualty incidents [69]. Another problem is the retention of EMS personnel due to the high-intensity physical and emotional work that the job demands. Burnout and job dissatisfaction may get translated into high rates of turnover, with the added problem of shortage entailing in the creation of a cycle of understaffing which may compromise patient care  [70].

Much of the equipment and supplies used to provide first response care are on the ambulances, including oxygen tanks, defibrillators, stretchers, and medications. Resource limitation subjects the workers to under-capacity utilization of equipment or outdated ones; most of these really limit the ways in which EMS personnel can effectively offer care [71]. If, for instance, there is no proven life support (ALS) equipment, the paramedics will not be in an adequate position to conduct critical techniques such as intubation or administration of intravenous drugs for various life-threatening conditions.

There have been documented instances where agencies, due to budgetary limitations, have themselves exposed to holding maintenance and replacement of critical equipment. When budgetary limitations, in fact, make the difference in whether the equipment will survive or function properly during patient care, the risks are that it may fail or malfunction. Critical medical supply may include medicines and other disposable medical devices that are important for care. Such things might happen in a hurry, more especially when a certain place has been hit by either a natural calamity, pandemic, or any other disaster [72].

Among the strategic approaches that may help deal with these resource constraints includes increase of funding on EMS services especially in poorly served areas.

It supports increased staffing and upgrading of equipment to ensure the better equipping of ambulances in such a way that most of the eventualities can be handled. Supporting training programs and retaining personnel should neutralize the workforce shortages as a general increase in the quality of care. New technologies demand the adoption of telemedicine, mobile health applications, and new ways to enhance the use of limited resources [73]. This provides an avenue for EMS personnel to consult with specialists and access immediate medical information in caring for patients. Again, efficient supply chain management involves the development of mechanisms that ensure regular availability of essential medical equipment and medication supplies during crises [74].

Ethical and Legal Issues

Patient autonomy and informed consent remain two of the most important ethical concerns in ambulance service. Implied consent is a legal concept that applies when a patient is incapable of giving consent or is unconscious. Because a reasonable individual would consent to such treatment in an emergency, this legal concept permits the EMS team member to offer necessary care [75]. But this could cause issues if the patient rejects the care received once he is able to give consent, potentially leading to legal issues. In order to solve these problems, EMS organisations should make sure that their staff members are well trained in informed consent principles and are aware of the legal parameters governing implicit consent. When obtaining patient agreement is not possible, precise procedures ought to be set up to direct the decision-making process [76].

It can be difficult to uphold patient anonymity in the prehospital setting, despite an EMS team member's basic ethical duty to do so. This may precipitate into possible legal consequences due to violations of various laws on privacy, like the Health Insurance Portability and Accountability Act [77]. The EMS agencies should, therefore, protect electronic information by putting in place very strong protection through encryption and security of the patient records. It is also vital that EMS personnel undergo periodic training on laws regarding confidentiality and the importance of patient privacy. In a resource-poor environment-such as could be experienced in a mass casualty event-the EMS provider may be compelled to make ethical decisions about how care is allocated [78]. Decisions pertaining to resource allocation may be scrutinized closely if they seem to be discriminatory in nature or lead to poor outcomes for patients. EMS agencies must formulate and put in place clear triage protocols based on the ethical principle and best practices [79]. This practice should be subjected to regular review and update, including training for all the personnel of the EMS on application, especially in situations of high pressure.

The practice range of an EMS personnel is legally and differentially defined based on location. There are, however, ethical and legal dilemmas exerted on the providers of EMS when one is asked or even obliged to perform certain practices out of their scope of practice, especially in life-threatening conditions that call for immediate attention [80]. It is imperative for EMS agencies to furnish unambiguous scope statements and guarantee that all staff are cognisant of the limitations of their practices. Programs for ongoing education and training are required in order to let emergency medical services (EMS) providers function legally and provide the necessary emergency care [78]. The use of education, explicit protocols, and procedures subject to routine evaluation by the EMS agency are some of the strategies used to address the ethical and legal issues surrounding the care of patients in ambulances. By doing this, the EMS staff will be trained on ethical concepts, legal requirements, and decision-making frameworks with confidence and competence. Second, strict guidelines for informed consent, privacy, using resources wisely, and honouring patient preferences may lower risks and be linked to higher-quality healthcare delivery. By conducting routine audits, revising these protocols, and consulting with legal experts, EMS providers may remain compliant with changing legal standards and be ready to tackle new difficulties as they arise [81].

The conclusion of this paper is that the growth of ambulance services has greatly improved patient care, even before they are admitted to hospitals. Even before patients get at a hospital, they may guarantee that they receive critical treatment thanks to the assistance of paramedics and EMTs in building ALS and BLS ambulances. This has significantly raised the level of care afforded the patients in the provisions of emergency medical services, especially in regard to timely emergency interventions. Ambulance services will be even more capable of delivering patients high-value care as soon as possible because continuous training and technical breakthroughs occur in the sector development.

Acknowledgments           

Authors are thankful to open access journals, Library and other open access database like DOAJ, Research Gate, Pubmed, and Google Scholar etc for providing the useful information to compile the article.

Authors Contribution

All authors were participated and contributing their efforts in the preparation of manuscript including table, figures and final proof of manuscript.

Conflict of interest statement

Authors declare they do not have any conflict of interest.

Funding

No funding support from any external source.

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