Injury Treatment and Rehabilitation Accessibility Queensland Index (iTRAQI) for Moderate-to-Severe Traumatic Brain Injury: Technical report for version 2.0

Traumatic brain injuries (TBIs) are a major cause of disability and death in Australia. Timely access to vital neurosurgical treatment is the key determinant of survival and recovery. Queensland’s health care system is mainly centralized along the East Coast, with major trauma treatment hospitals located only in the South-East corner and Townsville.

Emergency retrieval services are State-based and to cover Queensland’s vast distances and dispersed population requires both road (Queensland Ambulance Service) and air (Retrieval Services Queensland) transport.

Rehabilitation also plays a vital role in regaining functional capacity and improving outcomes. While the rehabilitation journey is different for each patient, all patients commence with specialised in-patient rehabilitation, which is available at/near the major trauma centres.

The aim of developing the injury Treatment and Rehabilitation Accessibility Queensland Index (iTRAQI) was to understand which areas had poor access to treatment and/or rehabilitation for moderate-to-severe TBI.

Appropriate patient transfers from 441 locations across Queensland (identified using Geoscape’s Administrative Boundaries for Queensland Town Points) to receive specialised neurosurgical acute care were determined by Retrieval Services Queensland and Queensland Ambulance Service. Aeromedical retrieval times used calculated flight times and expert clinical advice, while ambulance road travel times used off-peak speed limits on road networks via ArcGIS Online. Time for coordination, dispatch, on-scene and pre-major trauma centre facilities were also assigned as fixed amounts.

Access to brain injury rehabilitation care considered only the initial specialised in-patient public rehabilitation. Road travel times to rehabilitation facilities were calculated using off-peak speed limits and road networks.

Following initial development, this version of iTRAQI was compared against patient journey data to ensure it was reasonable. Although there were deviations from iTRAQI, no adjustments to iTRAQI were required.

Estimated median pre-hospital retrieval times across Queensland to neurosurgical acute care ranged from 47 minutes to over 8.7 hours, with the poorest access seen in areas such as the Torres Strait region and Central Queensland. Driving time to rehabilitation facilities ranged from approximately 5 minutes to over 22 hours, with the Torres Strait region having the poorest access.

The large disparities seen across Queensland, despite world-leading health, prehospital and retrieval services, highlight the importance of considering disease-specific accessibility indices. The travel times calculated for moderate-to-severe TBI are likely to be similar for other severe injury types requiring highly specialized care. iTRAQI provides a useful standard for auditing deviations in pre-hospital retrieval time or pathways, and highlights areas where improvements or alternative arrangements (such as provision of emergency surgery) are needed.