Medic Restraint Systems within the Patient Compartment
Those who work in Emergency Medical Services as medics have a difficult and dangerous job; the causes of which, EMS as an industry is only beginning to address. Currently, medics out on the field have differing priorities than the administrations and manufacturers who are tasked with keeping them safe. This makes attempts at mitigating detriment particularly challenging. Preventing medic fatalities within the patient compartment is particularly difficult to implement. This thesis lays an understanding of how that dichotomy manifested, and how fatalities in the EMS community are linked to manufacturer's failure to take into account the behaviors of the medics within the patient compartment when developing their solutions.
This thesis takes a transformative approach when addressing how a safety solution would work within existing user workflows, and how to make it more comfortably adopted. It sets out to identify what factors of a medic's job take the most toll, and uses a user-centered design methodology to offer a solution that satisfies both users' and administrators' goals. The solution consists of an overhead seat belt rail system attached safety harness that is integrated into the medic uniform. The value of this solution is an increased level of safety in the patient compartment that helps protect medics in the event of a crash, while allowing flexibility of movement so the medic may quickly and effectively treat their patient. Medics are subsequently less likely to be taken out of commission for injury, while also not compromising the level of care provided to the patient.
Defining the Problem
Competitive Product Analysis
Part 1: The Rail System
Part 2: The Harness
Harness x Uniform Integration
It's a Dangerous Job
It is estimated that EMS workers are three times more likely to suffer bodily injury and fatalities on the job than any other field in the United States. They also have much higher percentages of Post-Traumatic Stress Disorder (PTSD) than the general population, and are frequently exposed to dangerous blood-borne pathogens, disease, and infection. Identifying the nature of these hazards, and which one is the most pressing to address, is the first step to developing interventions that effectively improve EMS worker conditions. I began by asking which elements of medics' jobs (whether it be the tasks they must perform, the equipment they must use, or the environment they must operate in) cause the most detriment to the medics' wellbeing. From there I assessed whether it was a physical or mental element that was more significant, and whether the issue could be solved through design.
While medics might not be traditionally considered marginalized members of EMS organizations, it is clear that they, as the representatives of the industry interacting with the public, are most affected by changes in policy and procedure. They are also the ones who must bear the burden of policy changes as it has a direct impact on their daily lives and workflows.
Through my transformative worldview, I as the researcher played the role of advocate for medics needs, giving them a voice in the process of identifying issues that most affect them, and sought their aid as expert users in research and design process, since they are much more intimately aware of the space, procedures, and limitations than me as a researcher. My research placed emphasis on their daily lives and experiences as metrics for the success or failure of current conditions, and as identifiers of how decisions made by EMS organizations affect their current safety and workflows. Medics guided my decision making process within the solution space to make sure that, first and foremost, I solved their needs.
Because of the specific nature of EMS systems based on geography and culture, the structure of the research was a multi-phase, mixed methods comparative study.
The methods in this study were both qualitative and quantitative. Qualitative data were recorded in the form of researcher observations and semi-structured interviews. Qualitative data were obtained alongside quantitative measures of physiological stress, visual documentation of equipment, environment, and timeframes in which tasks were performed over 5 shifts in four Texas cities. A total of 90 hours of data was gathered across 28 emergency calls.
The purpose of collecting both quantitative and qualitative documentation was to develop a correlative story of researcher-observed obstacles and medics' behavior toward those problems, as well as their physiological stress-response to those obstacles. For example, a medic might not look stressed during a task, but a spike in heart rate might indicate their internal struggle. This helped triangulate what areas to focus on. The NASA Task Load index was then used to assess what aspects of the flagged tasks were eliciting responses in EMS workers; such as if problems were physical or mental in nature, or if it was impeding time constraints or perceived effort that resulted in rising frustration levels.
Results (A Lesson in Observation)
From the data I collected, time constraints contributed the most to paramedics' negative performance. Situational issues that ate into their time had the most harmful impact, such as trying to insert an IV needle into a rapidly dehydrating patient's veins, or waiting for backup to arrive to help remove injured patients from a crumpled vehicle, and were often correlated with feelings of helplessness and frustration. Unfortunately, these issues, though important to address when looking at EMS at the organizational level, do not yield very many product design opportunities.
However, in alignment with extensive reviews of existing literature, my observations alone captured another significant problem: that medics rarely wear their seatbelts. This observation was confirmed in followup interviews and analysis of injury data, which showed that the leading cause of fatalities in EMS workers were ground transportation accidents.
Currently in the industry, ambulances manufacturers cite prohibitive costs as the reason why crash tests are not performed on the patient compartment of the ambulance. Some tests have been done, but only to aid in incremental improvements that do not take into account medics most common positions and tasks around the compartment: namely the fact that medics are often in a standing, reaching, or crouching positions, or in the process of moving to different areas of the patient, and are rarely sitting in one spot long enough to buckle up.
Which highlights the question: If medics are going to move/stand anyway (and continue to ignore the seating innovations that are currently being done), how can they stay safe while doing so?
My User-Centered Design
Using surveys, storyboarding, group critique, and prototyping, I worked with medics to develop a solution that would work with their already-established workflow so they could continue to seamlessly rely on their time-saving shortcuts and muscle memory. I also worked with ambulance manufacturers to ensure that concepts were feasible and cost-effective.
A two-part system was developed consisting of a seat belt on a rail system outfitted into the patient compartment, and a corresponding medic uniform + harness.
The Rail System:
An overhead rail system that could be retrofitted for existing ambulances or integrated into current manufacturing systemsf was developed. It is recessed into the ceiling to prevent opportunities for headstrike, and allows room for tall medics. It consists of a seat belt spool that slides along a linear rail, which is mounted into a U shaped track positioned around the patient stretcher. This allows the medic to still have access to all areas of the patient, while being safely secured.
Movement without too much resistance or freedom is achieved using V-ball bearing systems that can navigate both curved and linear paths. They are placed on either side of the U shaped rail to help with smooth glide and distribution of weight. The linear rail uses untensioned pulley.
To lock instantaneously in the event of turbulence or a sudden change in momentum such as in a crash, I used existing seat belt assemblies that are able to extend and retract smoothly with intentional movements, yet have the ability to lock and hold users securely when needed. This uses centrifugal locks and momentum locks. To lock the linear system on its journey around the U shaped channel, a tooth and groove system is used. In its uninterrupted state, the teeth are held off the v ball bearing systems that guide it around the track by springs. If enough force is applied downwards, such as if the medic is no longer supporting their own weight, then the springs will compress, bringing teeth cast into the housing down, through a window in the bearing plate, to grip into grooves set in the rail system. All together, the medic will be held in place in the event they are knocked off their feet.
The corresponding medic uniform incorporates an under-clothes built-in harness similar to that of a parachute or fall harness (utilizing their already-proven safety construction and tried-and-true stitch patterns). It is incorporated into both the pants and shirt and unified at the waist by a belt. Its sewn-in nature prevent users from "forgetting to put it on" or having to "put on something extra".
A buckle exposed at the back allows the medic to clip into to the rail system, and a secondary clip at the waist connects the medic to the patient stretcher; operating much like a rock climbing lead, it anchors the medic to the ground as a stability measure. Safety thresholds for webbing material, such as breaking strength and resistance to abrasion, were based on existing standards for seat belts within the driver's compartment, and thinner, more breathable padding for pressure areas was chosen for washability and durability. User sizing took into account anthropometric data and current industry practices for issuing uniforms.
By implementing a user-centered approach to the problems found within the research stage, this thesis also suggests a viable safety solution that both elevates the safety of the medic while also improving the likelihood for adoption. Long term development and use of this solution can hope to see a decrease in medic fatalities in the event of a crash, keeping them healthy and able to have a longer, more fulfilling career. EMS organizations can also be more assured in their investments, because their workers will stay better able to work for a longer period of time, and ideally adding value to the community service they provide.
This thesis also offers to serve as a template within the EMS industry for how to identify and solve user-centered problems that truly address all stakeholders' needs by implementing a transformative application of investigative methods. If EMS equipment manufacturers follow user-advocacy perspectives when developing products and solutions, more meaningful products can be produced that have a higher success rate out in the field.