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Original article
Triaging older major trauma patients in the emergency department: an observational study
  1. William Lukin1,2,
  2. Jaimi H Greenslade1,2,3,
  3. Kevin Chu1,2,
  4. Jacelle Lang4,
  5. Anthony F T Brown1,2
  1. 1Department of Emergency Medicine, Royal Brisbane and Women's Hospital, Herston, Queensland, Australia
  2. 2School of Medicine, The University of Queensland, Herston, Queensland, Australia
  3. 3School of Public Health, Queensland University of Technology, Herston, Queensland, Australia
  4. 4Centre of National Research on Disability and Rehabilitation Medicine, School of Medicine, The University of Queensland, Herston, Queensland, Australia
  1. Correspondence to Dr William Lukin, Department of Emergency Medicine, Royal Brisbane and Women's Hospital, Butterfield Street, Herston, QLD 4029, Australia; Bill_lukin{at}health.qld.gov.au

Abstract

Background The objective of this study was to compare the triage category assigned to older trauma patients with younger trauma patients upon arrival to the emergency department. The focus was to examine whether older major trauma patients were less likely to be assigned an emergency triage category on arrival to the emergency department after controlling for relevant demographics, injury characteristics and injury severity.

Methods This was an observational study using data from the Queensland Trauma Registry. All trauma patients aged 15 years and older who presented to contributing hospitals between 1 January 2005 and 31 December 2009 with an Injury Severity Score (ISS)>15 were included. Logistic regression analysis examined the odds of assignment to emergency (Australasian Triage Scale (ATS) 1 or 2) versus urgent (ATS 3–5) treatment for patients across various age categories after adjustment for relevant demographics, injury characteristics and injury severity.

Results The study used data on 6923 patients with a median (IQR) age of 43 (26–62) years and a mortality of 11.4% (95% CI 10.7% to 12.2%). Compared with individuals aged 15–34, the adjusted odds of being assigned an ATS category 1 or 2 were 30% lower (OR=0.68, 95% CI 0.57 to 0.81) for individuals aged 55–75 years and were 50% lower (OR=0.46, 95% CI 0.37 to 0.56) for individuals aged 75 years or older.

Conclusions Among patients with an ISS>15, older major trauma patients were less likely to be assigned an emergency triage category compared with younger patients. This suggests that the elderly may be undertriaged and provides a potential area of study for reducing mortality and morbidity in older trauma patients.

  • triage
  • Trauma

https://doi.org/10.1136/emermed-2013-203191

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    Key messages

    • What is already known on this subject?

    • Older individuals have higher mortality following trauma than younger individuals. One factor that may contribute to poor outcomes is under-triage. Studies from the pre-hospital setting indicate that, compared to younger patients, older trauma patients are less likely to be identified as requiring urgent care.

    • Limited research has examined how older trauma patients are triaged upon presentation to the emergency department.

    What this study adds?

    • The study found that older trauma victims are less likely to be assigned a high acuity triage score in the emergency department than their younger, but similarly injured, counterparts.

    • Our data suggest that “up-triaging” of the older trauma patient may be required, which should start at 55 years to avoid unnecessary morbidity or mortality from older patients commencing trauma resuscitation with a comparatively lower triage category.

    Background

    In all, 38% of all injury-related deaths occur in individuals aged 75 years and older1 and with the ageing population, these figures are likely to increase. It is estimated that the proportion of Americans aged 65 years or older will increase from 13% in 2009 to 19% in 2030.2 Data from other Western countries suggest a similar increase from 13% in 2004 to 19% by 2021 in Australia3 and from 19% in 2010 to 23% in 2035 in the UK.4

    Older individuals have higher mortality following trauma than younger individuals.5–8 For older patients, relatively poorer physiological reserves, pre-existing medical conditions and medications are known to contribute to poorer outcomes. Medications commonly prescribed for older patients may mask and, therefore, delay the clinical recognition of shock.9

    An additional factor that may lead to poor outcomes in older patients is the way that they are triaged upon presentation to the emergency department (ED). Triage on presentation aims to match the patient’s clinical need to resources via the use of the Australasian Triage Scale (ATS). The ATS was developed as a means of providing standardisation of triage and has influenced the practice of ED triaging worldwide.10 Inappropriate triage adversely delays time-critical treatment and may divert unnecessary resources to minor trauma.11 Evidence from the prehospital setting suggests that older trauma patients are less likely to be identified as requiring urgent care and may consequently be undertriaged.12

    The objective of this study was to compare the triage category assigned to older trauma patients with younger trauma patients upon arrival to the ED. We hypothesised that older individuals would be less likely to be assigned an emergency triage category (ie, 1 (Resuscitation) or 2 (Emergent)) after controlling for relevant demographics, injury characteristics and injury severity.

    Method

    Research design and setting

    This was an observational study using data from the Queensland Trauma Registry (QTR). QTR was established in 1998 and collected data on seriously injured people in the state of Queensland, Australia. Queensland is situated in the north-east of Australia and has a population of approximately 4.5 million people. In 2005, 14 regional and tertiary public hospitals participated in the QTR, increasing to 20 hospitals in 2009. These hospitals are estimated to account for more than 90% of seriously injured patients admitted to Queensland public hospitals.13

    With some exclusions (eg, iatrogenic injuries and pathological fractures), patients were included on the QTR if they were directly admitted to, or transferred for admission to, a participating hospital for 24 h or more for the acute treatment of injury and were coded with an ICD-10-AM (the Australian modification of the International Statistical Classification of Diseases)14 code indicating trauma to single or multiple body regions.13 Patients who died after ED presentation (regardless of length of admission) also were included on the registry but patients who died before reaching hospital were not included.14 Cases were identified for potential inclusion on the QTR via a standard system report generated by the Emergency Department Information System which was cross-matched with hospital coded morbidity data to ensure all eligible injury patients were identified. Data were abstracted from the medical record for all eligible patients and manually entered on the database by QTR nurses trained and accredited in specialised injury coding, including the Abbreviated Injury Scale. Further details on data capture, collection and quality assurance methodologies for the QTR are available elsewhere.13

    For this study, all patients aged 15 years and older who met the QTR inclusion criteria between 1 January 2005 and 31 December 2009 with an Injury Severity Score (ISS) greater than 15 were included. Ethics approval for this study was granted by Queensland Health and The University of Queensland.

    Methods of measurement

    The ATS15 is used across Australasia to assess the urgency of treating a patient according to the following question: ‘This patient should wait for medical care not longer than…?’. The instrument consists of a 5-point ordinal scale ranging from 1 to 5 (table 1). ATS category 1 is assigned to patients with the highest clinical urgency necessitating immediate treatment.

    View this table:
    Table 1

    The Australasian Triage Scale (ATS)

    To compare the triage of patients across different age groups, the ATS score assigned to the patient at the first ED of presentation was used. Thus, for patients who were transferred from a regional referring hospital to a second hospital for definitive care, the ATS score from their regional referring hospital was used in this study.

    In addition to the first ATS score, the following information was extracted from the QTR database for each case to enable adjustments in multivariable analyses: demographic details, injury characteristics, injury severity and acute care factors. Demographic details included age and sex, and injury characteristics included cause of injury (transport crash, animal-related, fall, striking or other), nature of main injury (fracture, injury to nerve/vessel/muscle/tendon, injury to internal organ, intracranial injury or other), intent of injury (accidental, assault or other) and injury type (blunt or penetrating).

    Injury severity was assessed using the ISS16 and the Revised Trauma Score (RTS).17 Acute care factors included level of definitive care hospital (tertiary, large regional, small regional), mode of arrival to definitive care hospital (ambulance (fixed wing), ambulance (helicopter), ambulance (road), own transport or other) and transfer from another hospital (yes/no).

    Data analysis

    Data were analysed using IBM SPSS Statistics V.19 (SPSS Inc, Chicago, Illinois, USA). Descriptive statistics were used to compare the injury characteristics and triage categories across various age groups. Patients with missing data were excluded from the analyses. Logistic regression analyses were performed to determine whether age was a predictor of triage category after controlling for sex, ISS, injury characteristics and acute care factors. These potential confounding variables were selected for the model because of their clinical relevance in terms of determining triage category. All these variables displayed significant univariate associations with triage category. ATS was dichotomised as ATS 1 or 2 (Emergency) versus ATS 3–5 (Urgent) for the purpose of analysis. This breakdown was chosen because the triage guidelines indicate that major trauma should be categorised as ATS 1 or 218 and this categorisation reflects the difference between patients requiring emergency rather than urgent treatment. Age was divided into four categories; 15–34, 35–54, 55–74 and ≥75 years. ISS was entered as a dichotomous variable (ISS 16–24 vs ≥25). The cut-off of 25 was chosen because it was clinically meaningful in terms of increased mortality risk19 and provided approximately equivalent numbers in each stratum. RTS also was entered as a dichotomous variable owing to the non-linear effect of RTS on ATS and the high proportion of patients with an RTS of 7.8408. The categorisation reflected normal (7.8408) versus abnormal (<7.8408) physiology. All categorisations were determined a priori. A number of variables in the final logistic regression model assessed similar constructs (injury characteristics and injury severity). Therefore, multicollinearity was assessed using the collinearity diagnostics in SPSS, which found that in all instances, the tolerance was above 0.3 and the variance inflation factor below 3.5 (values less than 0.1 and greater than 10 respectively indicate issues with multicollinearity). Therefore, the collinearity in the data was deemed acceptable.

    Results

    The final sample thus incorporated 6923 patients (see figure 1) with a median (IQR) age of 43 (26–62) years and a mortality of 11.4% (95% CI 10.7% to 12.2%). The majority of patients were assigned an ATS category 1 (45.1%) or ATS category 2 (26.2%).

    Figure 1
    Figure 1

    Participant recruitment flowchart.

    Descriptive analysis was performed on injury characteristics within the four age categories (table 2). Compared with older individuals, a higher proportion of younger individuals were male and involved in a transport crash. The nature of the main injury differed across age groups with a higher proportion of younger individuals experiencing fractures; injuries to nerves, muscles or tendons; or injury to internal organs than older individuals. In contrast, older individuals experienced a higher proportion of intracranial injuries. Younger individuals experienced more assaults than older individuals.

    View this table:
    Table 2

    Injury characteristics by age

    When examining the severity of injury across age groups, the spread of ISS scores was wider among those aged less than 55 years compared with those aged ≥55 years (figure 2). Similarly, individuals aged less than 55 years varied more in their RTS in comparison with individuals aged ≥55 years (figure 2).

    Figure 2
    Figure 2

    Injury Severity Score (ISS) and Revised Trauma Score (RTS) across different age groups. Boxes denote 25th, median and 75th percentile and whiskers denote 5th and 95th percentiles.

    The unadjusted percentage of patients assigned to ATS category 1 or 2 versus ATS categories 3–5 differed across age groups (figure 3). A higher proportion of patients aged 15–34 years were assigned ATS category 1 or 2 compared with patients aged 55–74 years (difference=13.6%, 95% CI 10.6% to 16.6%) and ≥75 years (difference=30.8%, 95% CI 27.4% to 34.3%). Similarly, the proportion of patients assigned ATS category 1 or 2 was higher in the 35–54 year age group compared with the 55–74 year age group (difference=13.2%, 95% CI 10.1% to 16.4%) and ≥75 year age group (difference=30.5%, 95% CI 26.8% to 34%). Patients aged 55–74 years were more often assigned ATS category 1 or 2 compared with those patients ≥75 years (difference=17.2% CI 13.2% to 21.2%).

    Figure 3
    Figure 3

    Percentage of patients assigned to Australasian Triage Scale category 1 or 2 versus 3, 4 or 5 by age group.

    Figure 4 provides the adjusted OR for being assigned an ATS category 1 or 2 and the ORs for all other variables included in the logistic regression model. The final model improved prediction beyond the null model (χ2=2434.01, p<0.01) and provided adequate fit to the data (Hosmer–Lemeshow χ2=11.45, p=0.18, Nagelkerke r2=0.42). Compared with individuals aged 15–34, the odds of being assigned an ATS category 1 or 2 were 30% lower (OR=0.68, 95% CI 0.57 to 0.81) for individuals aged 55–74 years and were 50% lower (OR=0.46, 95% CI 0.37 to 0.56) for individuals aged ≥75 years. Greater injury severity, arrival by helicopter or road ambulance, being seen in a tertiary hospital and having a penetrating injury were all associated with increased odds of being assigned an ATS category 1 or 2. Having an injury to an internal organ, being assaulted and having a non-transport-related accident reduced the likelihood of being assigned an ATS category 1 or 2.

    Figure 4
    Figure 4

    ORs for Australasian Triage Scale (ATS) 1 or 2 and all other variables included in the multivariable analysis. Graph is presented on a logarithmic scale. Diamonds are adjusted OR and whiskers are 95% CIs. OR>1 indicates that the patient is more likely to be assigned to ATS 1 or 2. Conversely, OR <1 indicates that the patient is less likely to be assigned to ATS 1 or 2. Reference groups were: 15–34 years for age, Revised Trauma Score<7.8408, fracture for nature of main injury, accidental for intent of injury, fixed wing ambulance for arrival mode, transport related for external cause, regional hospital for hospital level and blunt injury for injury type.

    Discussion

    This is the first study examining how older major trauma patients are triaged upon arrival to the ED. The study found that older trauma victims in Queensland are less likely to be assigned an ATS category 1 or 2 (ie, the highest acuity) in comparison with their younger but similarly injured counterparts, and this effect is more pronounced as the patient becomes older. These results are in line with research indicating that older individuals were less likely to have a trauma team activated in the prehospital setting12 and were less likely to be diverted to a major trauma centre.20–22 The results are also in line with recent research which retrospectively examined the triage category assigned to patients over 65 and found that 22.5% were undertriaged.23

    The explanation for the differential triage of older patients is not clear. Previous research has noted that medications commonly prescribed for older patients may mask and, therefore, delay the clinical recognition of shock. Further, standard physiological triage variables such as heart rate and blood pressure may not identify severe injury in older patients.12 However, these hypotheses were not supported in our study as the analyses indicated that compared with younger individuals, older individuals remained undertriaged even after the physiological variables, as represented by RTS, were controlled for. Other possible explanations are that it is difficult to distinguish chronic deficits from injuries related to an external cause in the older population,20 that older patients may be poor historians, and that there is limited time at triage to identify mechanism or severity of trauma in a confused older patient.

    Another explanation for differential triage may be the mechanism and type of injury experienced by older adults. The data indicate that older patients have more falls than younger individuals and such falls may be resulting in intracranial injuries. Minor head injuries in older individuals tend to be relatively asymptomatic even in the presence of intracranial bleeding. This may contribute to differential triage of these patients. However, undertriage of older patients was seen after controlling for both mechanism and type of injury. Thus, there may be other factors contributing to the undertriage of older patients.

    While not explored in this paper, the experience of the triage nurse also may be a factor that influences the way patients are triaged. While there has been limited research on triage experience, one study found that older nurses make more accurate triage decisions compared with younger nurses for patients who present with acute myocardial infarction.24 Therefore, it is possible that less experienced triage nurses may undertriage older patients because they have less ability to recognise the potential for deterioration of an older trauma patient. Further research into the triage of older patients should consider the experience of the triage nurse as an additional explanatory variable.

    Whatever the cause for the undertriaging, the finding that older individuals are less likely to be assigned an ATS category 1 or 2 represents a potential area of study for reducing mortality and morbidity. Studies have indicated that early treatment with aggressive resuscitation and monitoring of the older patient improve outcome.25 ,26 Such treatment might be better facilitated by ensuring older patients receive an appropriately high initial triage category (1 or 2).

    A strength of the current study is its use of QTR data which were abstracted from the hospital medical record by data collection staff trained and accredited in specialised injury coding. Moreover, the QTR maintains the highest standard of data quality by providing education and training to all QTR data collection staff, using database validation rules, and performing routine quality assurance checks.13 However, the study also has a number of limitations. First, the observational retrospective nature of the study meant that we could not explore other reasons not captured on the QTR as to why the triage category assignment differed for older and younger patients. Undertriage is one potential explanation for the results but there may be unknown confounding factors that were not controlled for in this study. Further, we do not have data on the appropriateness of triage category assignment. Prospective studies gathering additional data on whether the triage category assigned to patients was appropriate according to their clinical situation are required to support the assumptions made in this paper.

    Second, we have not examined the patient's ultimate outcome within this study. Therefore, it is not possible to determine whether undertriaging is associated with adverse events in older individuals. Finally, there were some missing data on RTS, particularly for GCS, due to these data not being recorded in the patient's medical record. Compared with those with a recorded RTS, those with missing data on RTS were more severely injured (median (IQR) ISS 30 (24–41) vs 22 (17–26)) and more likely to be assigned to an ATS category 1 or 2 (99.5% vs 71.3%). This suggests missing data may influence the validity of the results to some degree. Patients with missing data on RTS were also younger (median (IQR) age 34 (23–52) vs 43 (26–62)), raising the possibility that missing data may also have influenced the effect of age on triage category. However, given that missing data comprised only 2.7% of the sample, and QTR used trained nurses to obtain the maximum possible information from the medical record on each patient, thus limiting the amount of missing data, this limitation is unlikely to have had a major impact on the findings.

    In summary, older trauma victims with an ISS>15 are less likely to be assigned an ATS category 1 or 2 on arrival to the ED compared with younger, similarly injured, people. Our data suggest that ‘uptriaging’ of the older trauma patient may be required, which should start at 55 years. Uptriaging may reduce unnecessary morbidity or mortality from older patients.

    Acknowledgments

    The operation of the Queensland Trauma Registry, and the work performed by its staff, ceased on 30 June 2012. The authors wish to acknowledge and thank all staff who worked at the QTR over many years for their commitment to data collection and improving trauma care in Queensland. The authors also would like to thank Lee Jones for providing statistical advice.

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    Footnotes

    • Contributors All authors contributed significantly to the research. WL, JHG, KC and JL contributed to study design. JG and JL analysed and interpreted data. WL and JG wrote the paper and all authors made critical intellectual contribution. All authors have read and approved the manuscript.

    • Funding Funding for this study was provided by a Queensland Statewide Trauma Clinical Network Research Grant.

    • Competing interests None.

    • Ethics approval Queensland Health Human Research Ethics committee.

    • Provenance and peer review Not commissioned; externally peer reviewed.