Study Design
This was a randomized controlled simulation study. Data was collected in Northern Sweden between February and June 2022. Each participant was randomly allocated into one of the 3 ‘treatment’ groups. The participating companies and or schools themselves sorted individuals by 3 into single groups. The individuals could not influence to which group they was assigned. The companies did not know more than that they were scheduling individuals for a training course that was part of a research project. Each ‘treatment’ group (of 3 individuals) was planned to comprise one of 10 teams for each ‘treatment’ arm. The exposures were as follows: Group 1 no course training and no telemedicine support during the simulation-based assessment. This same group then later (after the assessment) went further and participated in the training course and had a second assessment 4 to 6 weeks after their course, and this assessment group was called Group 4. Group 2 and Group 3 had telemedicine support during the assessment, Group 2 without pre-treatment training course and Group 3 with the completed training course prior to their assessment. All groups had access to standardized medical equipment during the simulation-based assessment. All groups participated in a full-scale, high-fidelity simulation-based major injury scenario for assessment where their performance was scored (described below). For the two groups who were allocated to receive the practical training course, the course was completed 4-6 weeks before the simulation-based assessment.
Study Population
With advertising for participants with cooperation of large building companies as well as local builder apprenticeship training programs in Sweden, individuals working on building sites as employees or apprentices were screened and recruited with cooperation of their employers. No Swedish language was an exclusion criterion.
Response scenario
For the planning and design of the scenario and simulation, with assessment and data collection, an expert group consisting of anesthesiologist, emergency nurse, ambulance nurse, trauma surgeon and safety experts from the construction industry was formed. The expert group designed a scenario that was realistic for the construction industry workplace environment. The expert group designed a 10-minute scenario with one injured person, 35 years old, previously healthy with multiple injuries caused by falls from 5 meters. The scenario contained 2 critical diagnoses, catastrophic bleeding and blocked airway, where early (first minutes) recognition and treatment of these can be presumed to be potentially life-saving. The premise for the injury event and response was that it was going to take a long time for ambulance personnel to arrive on site, and the responses here concerned what the participants would do during the first 10 minutes. The simulation was conducted with the help of a facilitator who had also been the first response course instructor, and a high-fidelity wireless computer operated human patient simulator (HPS) which was preprogramed with pathophysiology parameters specific for this scenario (see Table 1). Two behaviors were included in the scenario as secondary elements: a safety check for the accident site, and systematic head to toe survey and re-evaluation, commonly referred to as SCABCDE, to be able to detect other injuries.
Table 1. Scenario- critical diagnoses and assessment preprogrammed and set up in high fidelity simulator.
Name
|
Critical diagnosis and assessment
|
Human patient simulator
|
S
-Safety
|
Safe accident scene expected to be visually assessed 360 degrees
|
|
C
-Catastrophic bleeding
|
Catastrophic bleeding right femoral artery
|
0.5 liters of ‘blood’ was out on the ground at the source of bleeding, as well as pulsating bleeding
|
A-B
-Airway
-Breathing
|
Blocked airway
Apnea without airway management
|
Simulated chewing gum applied in the upper airway.
Recorded sound with signs of blocked airway, released when airway was secured. Cyanosis when blocked airway, blue light in the face, removed when secured airway.
Air stream on exhalation at secured airway
The chest moves up and down at the open airway, Breathing rate 20/minutes
|
C
-Circulation
|
Hypotension and tachycardia
|
Heartrate 130/minutes. Blood pressure 70/40
Pale skin color and simulated sweat. Palpable pulse A, carotid
|
D
-Disability
|
Unconscious does not react to pain. Equal pupils on the right and left sides
|
Does not respond to contact. Does not react to painful stimuli. Pupils same size, responsive and react to light
|
E
Exposure
|
Wound injury in the back of head. Inwardly rotated legs. Blood on the legs.
|
Made-up wound injury back of the head. Legs inwardly rotated
|
Catastrophic bleeding and airway control - defined primary critical outcome to evaluate.
The expert group prepared a simulation facilitator`s manual with the aim of standardizing the simulation. The manual described the expected life-saving measures which were required in order for the injury figure’s condition to improve in the simulation. The manual also described what help the facilitator could supply to the study participants, for example in the case where expected life-saving measures were not addressed, so-called ”Lifesaver” hints could be provided to allow the simulation to progress even if the participants were unable to demonstrate one or the other critical behavior in the first phase of the scenario.
Intervention
The telemedicine support intervention and content were based on a collaborative health care and constructive company project and 6-hour practical layperson trauma response training course with extended medical equipment [19], and in this way, the telemedicine response was informed as far as the medical equipment and what participants would have been exposed to if they had been ‘pre-treated’ with the trauma response course. The medical equipment ‘package’ which was available to all the participants during the simulation-based assessment included checklists that would assist field vital sign assessment and as well as equipment and instructions for communication with remote ambulance personnel through a telemedicine connection, even if they had not been exposed to this in a course.
First responder training course
The 6-hour practical trauma training course included an emphasis on assessment of the injured party and advanced critical life-saving procedures (direct pressure or torniquet, jaw thrust, oro - pharyngeal airway, laryngeal mask airway, bag-mask- ventilation, CPR+ defibrillator and pelvic sling) with accompanying systematic checklist (SCABCDE). The training course also included introduction of the telemedicine supporting system. The course began and ended with a 10-minute trauma response exercise, event-based training, and participant reflection in groups. The procedures were first introduced through instruction film and instructor demonstration, then the students practiced on a patient simulator, with feedback from the instructor.
Telemedicine support
The telemedicine system contained biosensors to transmit or measure the following medical parameters: breathing rate, oxyhemoglobin percent or saturation (SpO2), heart rate, blood pressure, electrocardiogram selected leads, and temperature. An already existing application was installed in a preprogrammed for-purpose smartphone connected to a server where, in addition to sending medical parameters to simulated ambulance personnel, the layperson at the accident site could also speak directly with the ambulance staff through a video call.
Simulation based assessment:
Based on recording of the participant performance during the standardized simulation, off-line analysis of participant behaviors using a pre-defined set of outcomes and time intervals was conducted. The scenario aimed to present clear signs of immediate life-threatening injuries in order to test for recognition and intervention behaviors, correct or incorrect. The whole scenario included the first 10 minutes of primary systematic prehospital trauma care, though the critical behavior period was defined as the first 2 minutes and 2 categories of responses. A detailed observation and scoring protocol was developed which followed the expected measures in the standardized scenario.
Before each group started the simulation-based assessment, the participants were given a standardized short orientation and introduction, including details about the training environment and how the simulator worked. After introduction, each participant completed a pre-assessment registration, where they recorded their sex, age, years in the profession, and any resuscitation training they had prior to this study. The simulation and response scenario was conducted in a standardized room, where the simulator figure was lying on their back on the floor. Next to the simulator was a medical bag with the above-described equipment, telephone, biosensors, and checklists/action cards. All groups had the same opportunity to use the equipment as they wanted. An instructor conducted the assessment simulation scenario. An emergency nurse acted as 1) simulated emergency call center operator and 2) simulated ambulance nurse for remotely video support. Before the test started, all groups had been informed to simulate a call to the Swedish central emergency alarm phone number/112 on arrival at the scene of injury event. The two groups that were randomized to receive video support were directly ‘called’ (telephone) by a simulated ambulance nurse, immediately after the call to 112, and the telemedicine distance guiding was started with the support of a checklist SCABCDE. The scenario and assessment period was stopped at 10 minutes. At this point, the group was asked to report back to the ambulance nurse on what they understood in the scenario, and what they had done as far as resuscitation. There were 2 primary outcomes, both within the first 90 seconds, which were early correct bleeding control by manual pressure within 60 seconds or applied torniquet in 90 seconds as a categorical variable, yes or no, and correct identification of occluded breathing passage and behavior to achieve an open breathing passage, also within 90 seconds. Secondary outcomes were assessed within the 10-minute time frame, and these included the following: correct top-to-toe examination finding wound injury in back of the head, also a categorical variable yes or no, time to completion of top-to-toe examination mean in seconds, correct fixation of pelvic injury a pelvic sling, categorical variables yes or no, and time in seconds to fixating a pelvic fracture with a pelvic sling.
Power calculation for a sample size
After intervention, either training course, ambulance tele-support, or both, the correct response for the critical behaviors was expected to be approximately 9 out of 10 based on earlier course experience. The expected baseline rate for responses or behaviors from completely unschooled or untutored participants was expected to be 25%. This meant an estimated or anticipated difference in proportions of 0.65, with power to detect a true difference of 80% and a 2-sided ‘alpha’ of 5% (0.05). This calculation indicates that a minimum of 8 sets of participants or groups should be in each paired analysis. A sample size of 10 for each set of groups was chosen, to allow for dropout.
Data management
A total of 40 simulation assessments were observed and recorded with two cameras and from two angles. Exposures were pseudoanonymized for the assessments, and for the analysis of the videos. The videos and observation protocol were encoded and stored on a server with a coded password to which only primary investigator had access.
Data Analysis
Analysis was conducted using IBM SPSS statistics, version 28. Descriptive statistics are presented both at individual level and at group level.
Group comparisons for the primary outcomes were done with a two sample test for proportions comparison. Comparisons for continuous variables where an approximately normal distribution could be assumed, was done with an independent samples t-test. Maximum time in the assessment scenario was 10 minutes or 600 seconds and groups that did not complete the expected procedure were assigned 600 seconds for that outcome. Significant differences between groups were identified when the p value was less than 0.05.
Ethical consideration
The study has been approved by the Swedish Ethical Review Authority (document number 2021-05774-01). All participants provided informed consent before entering the study.