Detailed description of the incident
A train broke down near the KLCC train station and the automated driverless system was disabled. A driver was assigned to manually restart the empty train and move it away. The train engine could be started and the driver moved it along the tunnel. There was a communication failure between the Operations Control Centre (OCC) and the driver. As a result, the train mistakenly entered the railway in the opposite direction of another incoming automated driverless train that was carrying 213 passengers. The driver saw the approaching train and reversed the train immediately. The incident occurred at 8.33 pm, in the tunnel that was 25.7 metres under the ground. The location was 150 metres from the Kula Lumpur City Centre (KLCC) train station. During the incident, the train that was carrying passengers was travelling at 40 kilometres per hour (km/h) whereas the manually driven train travelled at 20 km/h. Both trains collided head-on, causing passengers in the train, who did not have seat belts, to be thrown to the floor or hit other passengers, the steel poles, glass windows and walls of the train.
Early response at incident site
Immediately after the incident, the first alarm reached the alarm centre of the operation centre at 8.33 pm. When the incident occurred, there was blackout in the train. The emergency light came on subsequently. Agencies were notified within 5 minutes. Calls both from the railway operator and the public came to the 999 emergency call centre. Hospital Kuala Lumpur (HKL) received the call at 8.37 pm. The Fire and Rescue services were despatched along with their ambulances. Various other departments and agencies including the Police, Malaysian Civil Service, St John's Ambulance were alerted to respond. Private ambulances also voluntarily came despite not being alerted as photos and videos of the incident were shared and became viral on the social media. The tunnel was relatively dark with light sources every 8 metres (Figure 2A). A narrow maintenance walkway corridor was available on one side of the tunnel (Figure 2B-C). There were staircases and escalators leading to the ground floor passing an equivalent of 3 storeys building with platform on every level. The tunnel ventilation machine was switched on automatically when the temperature reached 58 0C. Train movements at the area were stopped by the railway control centre. The railway's emergency response team was immediately alerted to respond before the arrival of other agencies. First, the team started to evacuate passengers who could walk out of the train. Those who could not walk were then evacuated by the personnel from Fire and Rescue Services. This was in line with the Simple Triage and Rapid Treatment system (START) which had been repeatedly practised in our annual exercise drills in the past.
Zoning at the incident site
The zonings were established by the responders following the National Security Council's zonings recommendations (Figure 3). Originally, the zonings were in circular shape with 'red zone' in the centre as the impact site, followed by the 'yellow zone' and 'green zone' furthest from the centre. These zones respectively represent dangerous, relatively safe and safe area. Only those trained personnel equipped with protection equipment are allowed to enter the red zone. The yellow zone is for the establishment of the command post and the medical base station. The green zone is for the public and the press. This 'circular' pattern can be applied in flat surfaces of incidents. However, in this underground incident. modifications were made so that the 'red zone' was established from the train impact site, all the way to the first underground floor of the station platform. The 'yellow zone' was established on the second underground floor all the way to the station entrance. The 'green zone' was established outside the station (Figure 4). Passengers had to walk on a very narrow platform (0.6 metre wide) at the side of the tunnel to exit the tunnel. Rescue officers had to carry casualties who could not walk using stretcher on the same platform to the stairs up (Figure 2C). The train crash site was only 150 metres from the entrance to the KLCC train station and therefore, patients could be carried to the station and brought up using the available wide staircases. Although elevators and lifts were functioning, they could not fit the stretchers.
Prehospital resources available and alerted
There were 14 ambulances on the ground (Table 1). Four governmental agencies despatched a median (range) of 2 (1-5) ambulances. There were four private ambulance teams that volunteered to attend to the scene without being alerted officially. All ambulances were at the scene within 10 minutes of the incidence. Ambulances usages were optimal and enough in transporting all non-ambulating critical and critical patients to the hospital. Some ambulating patients took private hailing cars to the hospital by their own choice.
Response at hospital level
Hospital resources available and alerted
HKL is the primary responding hospital for any major incidents in Kuala Lumpur City Centre. It houses the Emergency Medical Call Centre (EMCC) which co-ordinates medical assistance. Hospital Ampang and Hospital Selayang are secondary responding hospitals in this region. HKL is the largest hospital in Malaysia and has a surge capacity that can handle 50 seriously injured MCI patients at any one time (Table 2). The initial information from the incident site reported that there were only 47 patients. Accordingly, a decision was made to send all injured patients to HKL. However, this was an underestimation as the final tally was 64 patients. Nevertheless, the hospital could handle this incident because majority of the patients were of 'green' category. In Malaysia, according to Emergency Medical and Trauma Services (EMTS) policy, triaging of cases are done based on colour code whereby red is critical, yellow is semi-critical and green is non-critical. 'Stand down' was announced at 11.37 pm at the incident site (3 hours and 4 minutes from the time of MCI).
Coordination and Command
HKL has a disaster plan for MCI management. As part of preparedness measures, simulations in the form of tabletop exercises as well as MCI drills were carried out every year. During the Covid-19 Pandemic, however, drills could not be performed. Nevertheless, indoor simulations for disasters were held. The disaster plan is available to all personnel via the hospital's website. The plan activation involved the usage of the term 'red alert' which meant hospital staff response was required and 'yellow alert', for which, staff were only required to be on stand-by mode to be called to the hospital if necessary. For 'red alert' there are two levels. Level 1 entails a response which mainly involves emergency department staff and additional key personnel from the hospital management and relevant departments. Level 2, on the other hand, implies a response by staff from all departments in the hospital. During this incident, 'red alert Level 1' was activated. The hospital disaster plan incorporates elements of the incident command system. The Hospital Director is the 'Hospital Commander' who oversees the whole response operation. Under him are two Coordinators: the clinical Coordinator and the administrative Coordinator. The clinical Coordinator role is assumed by the head of Emergency Department and focuses on operations. The administrative Coordinator heads the logistics, planning and financial matters. During the incident, the Emergency Zone Command Centre (EZCC) was the command post for all clinical activities in the Emergency Department which was headed by the emergency consultant on duty as 'EZCC Chief'.
Hospital alert plan and response
At HKL, the alert system was activated from the call centre to the emergency physician on duty. During the incident, the emergency physician updated the Head of Department (HOD) about the MCI situation. The alert was put into the department's management 'Whats App' group. The Hospital Director was informed about the incident by the HOD via a phone call. The Emergency Department and the hospital was immediately put under 'yellow alert' (on standby to receive patients). Soon after that, the hospital received three critical patients followed by 12 other patients transferred by ambulances from multiple agencies. All patients were triaged at the entrance, going through temperature and epidemiological check and subsequently placed at 'clean zones' as they did not fulfil the criteria for Covid-19 risk. The level of alert was raised to 'red alert Level 1'. This was decided depending on the consultant's assessment and confidence that the department could handle the incident. The consultant assumed the role of EZCC Chief according to the disaster plan and took charge of the management of patients at the Emergency Department's treatment zones in the hospital.
Actions that were taken by the EZCC Chief were as follows: 1) briefing for all staff; 2) staff who were about to end their shift were asked to stay back to assist; 3) all patients from the incident had infectious disease triage including temperature check and epidemiological assessment. They were subsequently moved into 'dirty' or 'clean' areas based on the triage; 4) all patients from the MCI had black-coloured tags to differentiate them from other patients; 5) every Emergency Department zone (critical, semi-critical and non-critical) was extended while canvas beds were set up; 6) patients' particulars, diagnosis, progress and dispositions were regularly updated on a designated white board in every zone; 7) key specialties teams were alerted including Anaesthesiology, Neurosurgery, General Surgery and Orthopaedics; 8) hospital management team was alerted 9) hospital bed managers were summoned, briefed and asked to prepare for bed disposition plans including ICU; 9) hospital operations room were alerted and prepared; and finally, a new area for X-Rays imaging, in the building outside the Emergency department was opened to cater for non-critical patients to speed up the imaging and avoid congestion which was a concern during the COVID-19 pandemic.
The Hospital Director and HOD joined the team within 30 minutes. The Hospital Director acted as the Hospital Commander whereas the HOD assumed the role of Clinical Coordinator as per the disaster plan. The afternoon staff stayed back and joined the night team, doubling the number of staffs from all categories. There were also 3 volunteer emergency physicians who came to assist from home upon hearing about the MCI from social media. All patients were handled smoothly and the information of all patients were updated on a white board in each zone. The hospital bed managers managed to find ICU and ward beds for all patients requiring admissions. Two patients opted to go to private hospital for treatment. Key specialty teams from the Neurosurgery, General Surgery, Anaesthesiology and Orthopaedics came and planned managements for cases referred to them. The 'doubled' capacity of emergency staff could handle all the casualties with no further need to call for extra team from home. 'Stand down' in the Emergency Department was announced at 1.38 am, on 25th May 2021 (5 hours and 1 minute from the time of call received)
HKL's Binary System during the Pandemic
Since the start of the Pandemic, the Emergency Department in HKL operated with a binary system whereby the treatment zones were divided into 'clean' and 'dirty' areas. The details of this system has been recently published . In short, with this system, the 'clean' areas catered for patients without symptoms of infectious disease whereas the 'dirty' areas are for those who have them. Each of the 'clean' and 'dirty' areas have segments for red, yellow and green patients. This dual 'clean' and 'dirty' areas reflect the 'binary' term. For the 'dirty areas', there was also an isolation ward equipped with 14 negative pressure beds in the Emergency Department catering for patients who were COVID-19 positive .
During the MCI, the red, yellow and red zones of the 'clean' area were extended as shown in Figure 5. None of the patients that came to the department had infectious disease symptoms nor epidemiological links. Therefore, all of them were treated in the extended 'clean area' that catered for the surge of patients. COVID-19 PCR tests were done on all seven admitted patients as part of the hospital protocol while the discharged patients did not have the test done because they had no fever, no COVID-19 symptoms, and no recent contact with a COVID-19 patient. Despite being in the 'clean' area, staff wore the minimum personal protective equipment (masks, face shields and gowns). On follow up, none of the discharged treated patients had any COVID-19 symptoms.
Beds occupancy rate during the Incident
At the time of the incident, HKL has an overall 52% bed occupancy rate. Bed capacity for patients was increased as an anticipation of increased COVID-19 cases. Elective surgery cases were stopped except for urgent and emergency surgery. ICU beds capacity was increased and some of the operation theatres were converted into ICU beds.
Clinical management of patients
There were 214 people in this incident, 213 passengers in the driverless train, and 1 manual driver of the other train. Victims were evaluated by the medical staff at the incident site. 64 (29.90 %) were injured and sent to HKL. 150 (70.09 %) did not sustain significant injuries and were released home. The injured patients had a mean (SD) age of 32.9 (10) years; 33 (51.6%) were males. The median (range) ISS of those seen at the hospital was 2 (1-43), only five (7.81%) had an ISS of 16 and more. The median (range) ISS for the patients of red category was 22.5 (13-31); for the yellow category 2 (1-6), whereas for the green category was 1 (1-2).
Table 3 shows the vital signs of the patients seen at the hospital. More than 60% were tachypnoeic (respiratory rate ³ 20 per minute), less than 10% were tachycardic (heart rate>120 beats per minute), and none was hypotensive. Two patients (3.1%) had severe traumatic brain injury (TBI) while one (1.6%) had moderate TBI. Soft tissue injuries were the most common type of injury which was sustained in 46 (48.4 %) patients followed by chest injuries in 13 (13.8%) patients (Table 4).
Six (9.4%) patients were triaged as 'red' (critical), 19 (29.7 %) as 'yellow' (semi-critical) and 39 (60.9%) as 'green' (non-critical). Seven (10.9 %) patients were admitted to the hospital (3 to the ICU, 3 to the ward, and 1 to a private hospital as requested by the patient). 56 (87.5%) were discharged home. Only 6 (9.38%) had surgeries. This included craniectomy in two patients to evacuate an intracranial bleeding and elevation of a depressed skull fracture; one patient had thoracolumbar vertebral fracture fixations, one had open reduction and internal fixation (ORIF) for a Le forte fracture of the face; one had ORIF of a forearm fractures, one had intramedullary hip screw, and one had debridement of the soft tissue. The admitted patients stayed in the hospital for a median (range) 7 (1-28) days. None of them died. During the MCI response period, the psychologist team was not summoned because the MCI response was completed within 4 hours from the time of arrival of the first patient. However, one patient was found to have depression and was referred for psychiatric consultation.
The Communication System
Malaysian government agencies which are involved in emergency management respond via a single '999' emergency number. The first call about the MCI was received from one of the passengers who was not injured. The Fire and Rescue Services Department was despatched within 5 minutes. Medical teams were on standby initially. Subsequently, when casualties were confirmed, ambulances from various agencies were despatched to the incident site. 'Government-integrated Radio Network' (GIRN) was used on the ground of which, walkie-talkies were integrated via same communication network among all relevant agencies. This included government hospitals, fire and rescue services, the police and civil protection agency. Hospitals use this system for communication with call centres of other hospitals and ambulance services. Internet-based messaging system in the form of 'Whats App' application was used internally in HKL to communicate with staff using 'group' created for department management. Table 5 describes the functionality of the communication systems utilised during the management of the current MCI. Walkie-talkie functioned well in almost all settings while it was less optimal in the hospital. Telephones were not used in the prehospital setting.