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In-hospital downgrading of the trauma team: Validation of the Academic Medical Center downgrading criteria
Injury, Int. J. Care Injured (2006) 37, 33—40
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In-hospital downgrading of the trauma team: Validation of the Academic Medical Center downgrading criteria P.H.P. Fung Kon Jin *, T.B.M. van Olffen ä, J.C. Goslings, J.S.K. Luitse, K.J. Ponsen Trauma Unit Department of Surgery, Academic Medical Center, University of Amsterdam, G4-137, Meibergdreef 9, Postbus 22660, 1100 DD Amsterdam, The Netherlands Accepted 23 May 2005
KEYWORDS Overtriage; Undertriage; Trauma Team; Downgrading; Triage; Trauma care; Trauma Team management
Summary Background: To reduce overtriage of trauma patients while at the same time minimising undertriage, an in-hospital triage tool was developed with the purpose of reducing the initial full trauma team (downgrading) in a structured and evidencebased manner. This study evaluated the effect on overtriage rates by the AMC downgrading protocol (AMCDP) consisting of 24 criteria scored during the primary survey. Patients and methods: We prospectively investigated if any of the patients treated by the downgraded trauma team (DTT) were undertriaged by the protocol. All patients fulfilling the definition of severely injured (SI) patients but treated by the DTT were deemed undertriaged patients. Overtriage was measured by the percentage of patients treated by a full trauma team (FTT) while not classified as an SI patient. Results: : A total of 220 patients were eligible and triaged by the AMCDP. After triage, 95 patients (43%) were treated by the DTT while 125 patients (57%) were treated by the FTT. A total of 66 patients (30%) met one or more of the criteria for an SI patient. None of these patients were treated by the DTT. Of the 125 patients treated by the FTT, 59 patients were not defined as SI. Conclusion: For the entire study population no undertriage was found, while implementation of the AMCDP reduced overtriage in the entire study population from 70% to 26.8%. Similar trauma centres can benefit from implementing the AMC downgrading protocol. # 2005 Elsevier Ltd. All rights reserved.
* Corresponding author. Tel.: +31 20 566 6626; fax: +31 20 691 4858. E-mail addresses: [email protected] (P.H.P. Fung Kon Jin), [email protected] (J.C. Goslings), [email protected] (J.S.K. Luitse), [email protected] (K.J. Ponsen). ä Deceased. 0020–1383/$ — see front matter # 2005 Elsevier Ltd. All rights reserved. doi:10.1016/j.injury.2005.05.045
34
Introduction With the designation of 10 Level-I trauma centres in the Netherlands in 1999, the prehospital and inhospital triage systems have become more important in providing a high quality trauma care. Prehospital triage systems have been developed and are constantly being renewed and adapted in order to stimulate an optimal distribution of trauma patients to the appropriate medical facilities, while in-hospital triage systems have focused on the appropriate and prioritised use of these facilities. However, the use of the current triage systems have resulted in a significant overtriage rate, in order to minimise missing significant injuries in trauma patients (undertriage). Overtriage can be described as the unnecessary mobilisation and use of medical resources for patients without significant injury, whilst undertriage is defined as the inadequate treatment of patients that are significantly injured. While an overtriage rate as high as 50% is acknowledged and even recommended by the American College of Surgeons Committee on Trauma (ACS/COT) in order to limit undertriage,2 the negative effects of overtriage have been proven to be significant. Studies have shown that overtriage is costly and results in inefficient use of staff and resources.10,8,14,7 Furthermore, it is reported that the excessive overtriage results in greater burdens on the major trauma centres and underutilisation of community hospitals participating in the regional system.7 Several studies have shown that the reduction of overtriage using two-tiered or three-tiered trauma response systems decrease both the expenses and time consumption of trauma care significantly, while maintaining a high level of trauma care with minimal undertriage.17,6,16,20,18,4 In order to reduce overtriage in our setting and minimise undertriage, we developed an in-hospital triage tool based on a reduction of the trauma team (downgrading) rather than an upgrade-system. The in-hospital triage is applied by the full trauma team
P.H.P. Fung Kon Jin et al. itself in our Level-I trauma centre and the full resources of the trauma team are only continued when needed, while at the same time ensuring that potentially serious injuries are not overlooked nor inadequately treated. The application of a downgrading system rather than an upgrading system was considered a safer approach for our institution, infrastructure, and regional trauma organisation. We hypothesised that using this triage with a downgrading-system, a significant reduction of overtriage could be established without increasing undertriage or otherwise affecting patient care negatively. This study will evaluate the implementation of the AMC downgrading criteria protocol and the effect on both overtriage rates and outcome of the admitted trauma patients.
Patients and methods Study setting The Northwest-Netherlands Trauma Center is one of the 10 designated Level-1 trauma centres in the Netherlands, constituted by the two university hospitals in Amsterdam, and covers approximately 2.7 million inhabitants. The Academic Medical Center (AMC) is one of these two hospitals and is responsible for its part of the 1200 trauma victims that are distributed over the Northwest-Netherlands Trauma Center. The AMC trauma team sees approximately 600 emergency trauma patients per year, of which roughly 25% have an injury severity score (ISS) of 16 or higher. All these trauma patients are initially seen by the entire trauma team in one of the two trauma resuscitation rooms (shockrooms) available in the Emergency Department (ED), one of which is equipped with an overhead X-ray installation and an adjacent radiology viewing area. The decision for a patient to be transported to a Level-1 trauma centre is currently based on the triage and expertise of the prehospital Emergency
Table 1 Members of initial (full) and ‘downgraded’ Trauma Teams Initial (full) Trauma Team members Trauma Surgeon (ATLS certified) General Surgery Senior Resident (ATLS certified) General Surgery Junior Resident Anaesthesia Physician/Senior Resident Anaesthesia Nurse Radiologist/Senior Resident Radiology Technician (2) Trauma Nurse (2) Neurologist/Senior Resident (Neuro Trauma)
Downgraded Trauma Team members General Surgery Resident (ATLS certified)
Radiologist/Senior Resident Radiology Technician (2) Trauma Nurse (1)
The table shows the members for both the initial and downgraded Trauma Team. ATLS: advanced trauma life support.
In-hospital downgrading of the trauma team Medical Services personnel, following the PHTLSprogram.15 Based on their initial evaluation, the ED of the closest available trauma centre of the appropriate level as stated in the ambulance transport protocols is notified of the incoming Shockroom patient. In our centre, the entire trauma team is then notified through the in-hospital pager system. In Table 1, the composition of the trauma team is shown. All patients are examined and treated according to the ATLS-protocol as defined by the American College of Surgeons in 1997.1 Prior to the introduction of this protocol, the trauma team was not defined. In January 2002, the main shockroom was equipped with a video registration system after legal approval was obtained. On each arrival of a patient in the shockroom this registration is started.
Study design This study was conducted between 1st July 2002 and 31st December 2002, by means of a prospective study supported with video registration. All patients that were initially identified by the prehospital ambulance services as a ‘shockroom’ trauma in need of the trauma team were prospectively entered into the study. Patients 15 years or younger were excluded from the study. The other exclusion criteria were incomplete video registration, incomplete data collection or patients not transported by ambulance. Prior to the data collection, a list of physical and anatomical findings that would determine the need for a complete trauma team was assembled based on the current available literature.3,13,6,16,9,1,12,18,2, 15,19 These criteria were used to derive the downgrading flow chart (DFC) (Table 2). The result of the first AP chest X-ray was included in the DFC. With the presence of one or more positive criteria, the need for a full trauma team was deemed necessary. All criteria that were chosen for the DFC are obtained during the primary survey and after the first chest X-ray. If none of the criteria in the DFC was positive, the trauma team would immediately be reduced to the reduced (downgraded) trauma team (Table 1). The downgraded trauma team would proceed following the ATLS-protocol and treat the patient accordingly. At any time, if the status of the patient deteriorates, or the secondary survey reveals parameters that would retrospectively preclude the possibility of downgrading, or the patient requires the attention of the entire trauma team, the trauma team would be upgraded to its original composition immediately, using the in-hospital pager system. When downgrading was not indicated based on the downgrading criteria,
35 the trauma team would remain intact and treat the patient following the standard ATLS-protocol and all other standard operating procedures and policies as performed prior to this study and all attending team members stay in the Shockroom until the patient is transferred. Demographic and clinical data were collected for all patients and entered into a database. Demographic data included mechanism of trauma, age, gender, and injury severity score (ISS). With respect Table 2 ‘Downgrading’ criteria used for maintaining initial Trauma Team Airway A1: A2: A3: A4:
criteria (Impending) Airway obstruction Severe maxillofacial injury Risk of aspiration (bleeding, vomiting) Facial burn/inhalation trauma
Breathing criteria B1: Respiratory rate <10/min or >30/min Thoracic Injury: B2: Flail chest B3: Tension pneumothorax B4: Open pneumothorax B5: Chest X-ray with injury (except simple pneumothorax or <3 costal fractures for costae 4—9) Circulation criteria C1: Shock (systolic BP 90 mm Hg, pulse >120/min or < 50/min C2: Penetrating injuries to head, neck, thorax, abdomen and/or pelvic area C3: Abdominal tenderness C4: Hypothermia (T <328C) Burns: C5: Second and third degree burns >20% of body surface area C6: Second and third degree burns >10% of body surface area (age > 50) C7: Electrical burns Disability criteria D1: GCS <14 D2: Abnormal pupils D3: (Signs of) Spinal cord injury with neurological impairment D4: (Signs of) Basal skull fracture Exposure criteria E1: Unstable or open pelvic fracture E2: Two or more proximal long-bone fractures E3: Traumatic amputation above knee or above elbow E4: Penetrating injury proximal to knee or elbow The table shows the criteria used for maintaining the full, initial, trauma team. At least one positive criterion after the primary survey and first successful chest X-ray requires the full trauma team to stay intact, while the absence of all criteria leads to the reduced trauma team.
36 to the downgrading protocol, patients were classified into two groups: all patients that were treated by the complete trauma team were classified as ‘full team’ trauma patients, while patients that were treated by the reduced trauma team were designated ‘downgraded’ trauma patients. To determine the correct appliance of the downgrading protocol, each patient was analysed using the video registration and then categorised into the groups labelled ‘according to protocol’ (ATP) or ‘violation of protocol’ (VOP) based on whether the protocol was followed as instructed or not. To determine the safety of the protocol, a number of primary outcome criteria were defined (Table 3). The primary outcome criteria included mortality due to trauma, emergency procedures performed during initial evaluation, emergency surgical operations performed after initial evaluation in the shockroom, and type of ward to where patients were initially transferred (Table 3). All patients that had at least one of the primary outcome criteria were defined as ‘severely injured trauma patients’, while patients that did not meet at least one of the primary outcome criteria were deemed ‘not severely injured trauma patients’. All patients that were defined as ‘severely injured’ while treated by the downgraded trauma team, were considered ‘undertriaged’ trauma patients, while patients that were classified as ‘not severely injured’ and treated by the full trauma team were classified as ‘overtriaged’. Table 3 Primary outcome criteria for a severely injured patient Emergency procedure within 2 h of Admission Intubation or surgical airway Chest tube insertion Needle thoracocenthesis Pericardiocenthesis
P.H.P. Fung Kon Jin et al.
Statistical analysis Data were analysed for all eligible, included patients. All continuous variables are presented as mean S.D., and analysed using either the independent t-test with 95% confidence intervals or the Mann—Whitney U-test depending on the distribution. Categorical variables are calculated as percentage of frequency of occurrence. Discrete variables were compared using x2 analyses. Statistical significance was declared at the 0.05 level. All data management and statistical analyses were performed on a personal computer using both SPSS Data Entry Builder and SPSS Data Entry Station version 3.03, and SPSS Base for Windows, version 11.5, respectively (SPSS Inc., Chicago, IL).
Results Demographics Between 1st July and 31st December, a total of 254 consecutive trauma patients were admitted to the shockroom of the AMC. From this cohort, 220 patients were included in the study with a complete video registration and 16 years or older (Fig. 1). Of the 34 excluded patients, 24 patients did not meet the age criterion and 10 patients had an incomplete data collection. The mean age for the study group was 39.0 15.6 years with 148 (67.3%) male patients (Table 4). The female patients were significantly older (42.3 versus 37.4 years) than the male patients ( p < 0.05). Twenty-four patients (10.9%) were admitted due to penetrating injuries, and 51 (23.2%) patients were admitted with an ISS of 16 or higher.
Downgrading Emergency surgery within 2 h of admission Thoracotomy Laparotomy Craniotomy Surgical decompression spinal cord Amputation/revascularisation External fixation of pelvic fracture Fixation of 2 proximal long bone fractures Intensive Care Unit admission within 24 h Death within 48 h due to traumatic injury The table shows the criteria that have been used to define the seriously injured trauma patient for the study. All patients that meet at least one of the above mentioned criteria are designated as a severely injured patient that should be treated by the full Trauma Team.
In 95 (43.2%) cases, the trauma team was reduced after completing the DFC (Fig. 1). The median ISS value for the downgraded group was 1, with a range from 1 to 17. After downgrading it was never necessary to restore the trauma team to its original composition. Of the 95 downgraded trauma patients, 93 were downgraded according to the downgrading protocol having no positive criteria, while two cases were downgraded despite having one positive criterion (Table 5). The mean time necessary for the full trauma team to be reduced to the downgraded trauma team was 12 6 min. Of the two incorrectly downgraded patients, patient I (Male, 21 year, ISS 1) was haemodynami-
In-hospital downgrading of the trauma team
37
Fig. 1 This figure shows the complete study population, including the excluded patients. The patients that were included are divided in downgraded trauma team patients and full trauma team patients. These groups are further divided in subgroups, based on whether protocol was followed correctly. ATP: According to protocol, VOP: violation of protocol.
cally stable and showed no signs of injuries on the chest X-ray after falling through a glass door. The patient was released from the hospital without complications after the results of the second chest X-ray. Patient II (Male, 39 year, ISS 10) was alert and haemodynamically stable during the initial resuscitation phase following an abdominal stab wound, did not show signs of abdominal tenderness, and Focused Assessment with Sonography (FAST) was
negative for abdominal bleeding. After 12 h of observation, the patient showed signs of abdominal tenderness and shock, and required laparotomy for a perforation of his stomach and serosal injury of the transverse colon. He was released after 7 days without further complications. Both patients should have been treated by the full trauma team based on the presence of a penetrating injury proximal of the knees and elbows.
Table 4 Demographics Group (n)
Median ISS (range)
ISS 16 (%)
Mean hospital stay (days)
Gender (% male)
Study population (220) Downgraded patients (95) Full Team patients (125) Downgraded ATP (93) Full Team patients ATP (104) Severely injured patients (66) Non-severely injured patients (154)
5 1 9 1 13 20 1
51 2 49 2 49 45 6
7.2 12.3 3.1 6.3 10.3 14.6 3.1 6.4 11.4 15.5 3.7 7.1 15.3 17.1
67.3 58.9 73.6 58.1 77.9 74.2 64.3
(1—66) (1—10) (1—66) (1—17) (1—66) (4—66) (1—38)
(23.2) (2.1) (39.2) (2.2) (47.1) (68.2) (3.9)
The table shows the demographics for the study population and the defined subgroups. ATP: according to protocol.
Table 5 Criteria for maintaining the full Trauma Team Positive criteria
Downgraded patients n = 95 (%)
Full Team patients n = 125 (%)
Total n = 220 (%)
0 1 2 3
93 2 0 0
22 55 22 26
115 57 22 26
(97.9) (2.1) (0) (0)
(17.6) (44.0) (17.6) (20.8)
(52.3) (25.9) (10.0) (11.8)
This table shows the number of positive downgrading criteria found for the entire study population, the downgraded patients, and the Full Team patients.
38
P.H.P. Fung Kon Jin et al.
Table 6 Primary outcome criteria Outcome criterion
Downgraded patients n = 95 (%)
Full Team patients n = 125 (%)
Total n = 220 (%)
Death < 48 h Emergency surgery <2 h Intensive Care Unit admission Emergency Procedure < 2 h Severely injured patients Total surgical interventions Total mortality
0 (0) 0 (0) 0 (0) 0 (0) 0 (0) 15 (15.8) 0 (0)
10 24 72 34 66 56 15
10 24 72 34 66 71 15
(8.0) (19.2) (57.6) (27.2) (52.8) (44.8) (12.0)
(4.5) (10.9) (32.7) (15.5) (30.0) (32.3) (6.8)
The table shows the primary outcome criteria for the entire study population, the downgraded patients, and the full team patients. In addition, also included in this table are the total number of patients undergoing surgical interventions and total mortality found.
The remaining 125 patients were treated by the full trauma team. The median ISS for the patients treated by the full trauma team was 9, ranging from 1 to 66. In 21 patients however, no positive criteria were present and the downgrading protocol was violated (median ISS 4, range 1—14). For the remaining 104 patients, the trauma team remained complete in accordance with the protocol, diagnosed with one or more positive criteria (Table 5).
Primary outcome A summary of the primary outcome for all four subgroups can be found in Table 6. Sixty-six (30.0%) of the patients met at least one of the criteria classifying a severe injured patient. Mean ISS for this group was 21.9 13.3. The overall mortality of the included study group was 6.6% (n = 15). One of the 15 deceased patients died unrelated to a traumatic injury (myocardial infarction). The remaining 14 patients died or were pronounced brain dead within 8 days of the accident. A total of 71 patients were operated upon, including three post-mortem for organ donation. Of the remaining 68 operated patients, 24 patients underwent emergency surgical interventions as described in Table 3. None of these 24 patients were treated by a downgraded Trauma Team. There were a total of 72 admissions to the Intensive Care Unit. The mean hospital stay for downgraded patients (3.0 days) was significantly shorter than for the full team patients (9.9 days) ( p < 0.001).
Discussion This study investigated if downgrading of the trauma team using the AMC downgrading criteria is a safe way to reduce overtriage of trauma victims, without negatively influencing patient outcome. The current
organisation for trauma care on both the regional and institutional level requires our centre to have the entire trauma team present when the patient arrives at the shockroom, in order to guarantee the optimal level of trauma care as described by the ACS/COT.1,2 The study results suggest that an accurate selection is made by the AMC downgrading protocol based on the physiologic and anatomic data collected during the primary survey, leading to a significant reduction of overtriage without a case of undertriage. The fact that there has been no undertriage also implies that no extra criterion is needed. It is interesting to note that the addition of the first conventional chest X-ray results as a selection criterion was the main reason why nine severely injured patients were not missed: the full trauma team was maintained based purely on the results from the chest X-ray for 11 patients. Of these 11 patients, 9 were classified as severely injured, while 2 were overtriaged by the chest X-ray criterion. The overall overtriage rate that remains present after implementation of the AMC downgrading criteria is approximately 27% of all shockroom patients. While this number still seems high, one has to keep in mind that prior to the study and implementation, all downgraded patients would have been treated by the complete trauma team, which would have led to 153 overtriaged patients (69.5%). Also when analysing the implementation of the downgrading protocol, a significant learning curve was noted. Most of the patients that should have been downgraded but due to protocol violation were kept in the full team patients group, were seen in the first two months of the study. With the reduction of this group, the overtriage rate would have decreased even more. A possible improvement of the AMC downgrading criteria might be an adjustment for the penetrating injury criterion. Evaluation of the patients in the full team group with just one positive criterion shows that the least specific criterion is that of penetrating
In-hospital downgrading of the trauma team injuries. However, although this criterion shows a significant number of overtriaged patients, it cannot be overlooked that the criterion also identified several patients with penetrating injuries were severely injured and required immediate attention of the multidisciplinary trauma team. Furthermore, the two protocol violations that were downgraded despite having one positive criterion on the DFC, both had sharp injury proximal to the knees and elbows. When reviewing the patient with the sharp injury to the back after falling through a glass window, it seems reasonable that a superficial cut without deep penetration and no injury on the chest X-ray does not require the full trauma team. However, with the current downgrading criteria, no difference is made between a superficial penetrating injury proximal to the knees and elbows, and a deep penetrating sharp injury. Strictly speaking, this patient should have been treated by the full team. A possible solution is a more accurate description for the sharp injuries to neck, thorax, abdomen, and groin that require the full trauma team, or a combination of criteria in case of a sharp injury, in an attempt to reduce the overtriage due to the penetrating injury criterion. The composition of our trauma team does not comprise medical specialists who are solely available for the trauma team. Therefore, these people are interrupted in their clinical activities to form the trauma team for each pre-notification of a shockroom patient. This leads to delays in several departments (including operating rooms), from the moment the trauma pager is activated until the team member can return to his/her previous activity. In the clinical setting prior to the AMC downgrading protocol, the moment for each member to return to their original post remained unclear and resulted in a mismanagement of valuable people and resources. With the introduction of the downgrading protocol, an attempt is made not only to create a clear guideline for each trauma team member, but also to stimulate a more efficient working environment. A recent study at our centre evaluated the impact of the trauma team patients on the Emergency Department’s efficiency based on a theoretical management model and described the beneficiary effect of the early return of one of the two trauma nurses to the Emergency Department.11 Although no exact data are available on the effect of the downgrading protocol on other in-hospital departments, it can be assumed that the early and structured return of trauma team members to their prior activities can only contribute to hospital efficiency and eventually, patient care.
39 While the expertise in the prehospital setting, along with the communication between the prehospital services and the in-hospital trauma care clearly show signs of improvement, not every trauma centre is currently suited to reduce overtriage by using a two- or three-tiered trauma response.5 Although several studies have shown that a two-tiered trauma response system can further decrease overtriage rates, the same studies have also shown an increase in undertriage rates, albeit minor.4,6,7,16—18,20 Ryan et al. showed that using a two-tier triage system, their overtriage rates dropped to 10%. However, they also reported 8% undertriage of patients.18 While we acknowledge that our system is still far from perfect, the fact that we were able to reduce overtriage without any undertriage can have a significant impact on all centres that are in a similar situation as ours. Even renowned centres that use two- or three-tiered trauma response systems could benefit from applying our tool to further reduce overtriage using evidence based medicine. Using the physiological and anatomical criteria as used in the downgrading protocol a quick and accurate assessment can be made to determine whether the patient will benefit from the initial, full trauma team. With this study, we have demonstrated that the AMC downgrading protocol is a safe and effective way for reducing overtriage in our institution.
References 1. American College of Surgeons, Committee on Trauma. Advanced trauma life support program for doctors ATLS. sixth ed. Chicago: American College of Surgeons 1997. 2. American College of Surgeons, Committee on Trauma. Resources for optimal care of the injured patient: 1999. Chicago: American College of Surgeons 1998. 3. Champion HR, Sacco WJ, Hannan DS, Lepper RL, et al. Assessment of injury severity: the triage index. Crit Care Med 1980; 8:201—8. 4. Cook CH, Muscarella P, Praba AC, Melvin WS, et al. Reducing overtriage without compromising outcomes in trauma patients. Arch Surg 2001;136:752—6. 5. Deane SA, Gaudry PL, Pearson I, Misra S, et al. The hospital Trauma Team: a model for trauma management. J Trauma 1990;30:806—12. 6. DeKeyser FG, Paratore A, Seneca RP, Trask A. Decreasing the cost of trauma care: a system of secondary inhospital triage. Ann Emerg Med 1994;23:841—4. 7. Esposito TJ, Offner PJ, Jurkovich GJ, Griffith J, et al. Do prehospital trauma center triage criteria identify major trauma victims? Arch Surg 1995;130:171—6. 8. Flancbaum L, Dougherty C, Brotman DN, Avedian J, et al. DRGs and the ‘‘negative’’ trauma workup. Ann Emerg Med 1990;19:741—5. 9. Henry MC, Alicandro JM, Hollander JE, Moldashel JG, et al. Evaluation of American College of Surgeons trauma triage criteria in a suburban and rural setting. Am J Emerg Med 1996;14:124—9.
40 10. Hoff WS, Tinkoff GH, Lucke JF, Lehr S. Impact of minimal injuries on a Level-I trauma center. J Trauma 1992;33:408—12. 11. Hoomans T. De afdeling spoedeisende hulp van het ziekenhuis onder behandeling. Master of Engineering thesis. University of Twente, the Netherlands 2003. 12. Kaplan LJ, Santora TA, Blank-Reid CA, Trooskin SZ. Improved emergency department efficiency with a three-tier trauma triage system. Injury 1997;28:449—53. 13. Knudson P, Frecceri CA, DeLateur SA. Improving the field triage of major trauma victims. J Trauma 1988;28:602—6. 14. MacKenzie EJ, Morris Jr JA, Smith GS, Fahey M. Acute hospital costs of trauma in the United States: implications for regionalized systems of care. J Trauma 1990;30:1096—101. 15. National Association of Emergency Medical Technicians PreHospital, Trauma Life Support Committee, American College of Surgeons Committee on Trauma. PHTLS: basic and
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17. 18. 19.
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advanced prehospital trauma life support. fourth ed. St. Louis: Mosby 1999. Ochsner MG, Schmidt JA, Rozycki GS, Champion HR. The evaluation of a two-tier trauma response system at a major trauma center: is it cost effective and safe? J Trauma 1995; 39:971—7. Phillips JA, Buchman TG. Optimizing prehospital triage criteria for Trauma Team alerts. J Trauma 1993;34:127—32. Ryan JM, Gaudry PL, McDougall PA, McGrath PJ. Implementation of a two-tier trauma response. Injury 1998;29:677—83. Tinkoff GH, O’Connor RE. Validation of new trauma triage rules for trauma attending response to the emergency department. J Trauma 2002;52:1153—8. Tinkoff GH, O’Connor RE, Fulda GJ. Impact of a two-tiered trauma response in the emergency department: promoting efficient resource utilization. J Trauma 1996;41:735—40.
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In-hospital downgrading of the trauma team: Validation of the Academic Medical Center downgrading criteria P.H.P. Fung Kon Jin *, T.B.M. van Olffen ä, J.C. Goslings, J.S.K. Luitse, K.J. Ponsen Trauma Unit Department of Surgery, Academic Medical Center, University of Amsterdam, G4-137, Meibergdreef 9, Postbus 22660, 1100 DD Amsterdam, The Netherlands Accepted 23 May 2005
KEYWORDS Overtriage; Undertriage; Trauma Team; Downgrading; Triage; Trauma care; Trauma Team management
Summary Background: To reduce overtriage of trauma patients while at the same time minimising undertriage, an in-hospital triage tool was developed with the purpose of reducing the initial full trauma team (downgrading) in a structured and evidencebased manner. This study evaluated the effect on overtriage rates by the AMC downgrading protocol (AMCDP) consisting of 24 criteria scored during the primary survey. Patients and methods: We prospectively investigated if any of the patients treated by the downgraded trauma team (DTT) were undertriaged by the protocol. All patients fulfilling the definition of severely injured (SI) patients but treated by the DTT were deemed undertriaged patients. Overtriage was measured by the percentage of patients treated by a full trauma team (FTT) while not classified as an SI patient. Results: : A total of 220 patients were eligible and triaged by the AMCDP. After triage, 95 patients (43%) were treated by the DTT while 125 patients (57%) were treated by the FTT. A total of 66 patients (30%) met one or more of the criteria for an SI patient. None of these patients were treated by the DTT. Of the 125 patients treated by the FTT, 59 patients were not defined as SI. Conclusion: For the entire study population no undertriage was found, while implementation of the AMCDP reduced overtriage in the entire study population from 70% to 26.8%. Similar trauma centres can benefit from implementing the AMC downgrading protocol. # 2005 Elsevier Ltd. All rights reserved.
* Corresponding author. Tel.: +31 20 566 6626; fax: +31 20 691 4858. E-mail addresses: [email protected] (P.H.P. Fung Kon Jin), [email protected] (J.C. Goslings), [email protected] (J.S.K. Luitse), [email protected] (K.J. Ponsen). ä Deceased. 0020–1383/$ — see front matter # 2005 Elsevier Ltd. All rights reserved. doi:10.1016/j.injury.2005.05.045
34
Introduction With the designation of 10 Level-I trauma centres in the Netherlands in 1999, the prehospital and inhospital triage systems have become more important in providing a high quality trauma care. Prehospital triage systems have been developed and are constantly being renewed and adapted in order to stimulate an optimal distribution of trauma patients to the appropriate medical facilities, while in-hospital triage systems have focused on the appropriate and prioritised use of these facilities. However, the use of the current triage systems have resulted in a significant overtriage rate, in order to minimise missing significant injuries in trauma patients (undertriage). Overtriage can be described as the unnecessary mobilisation and use of medical resources for patients without significant injury, whilst undertriage is defined as the inadequate treatment of patients that are significantly injured. While an overtriage rate as high as 50% is acknowledged and even recommended by the American College of Surgeons Committee on Trauma (ACS/COT) in order to limit undertriage,2 the negative effects of overtriage have been proven to be significant. Studies have shown that overtriage is costly and results in inefficient use of staff and resources.10,8,14,7 Furthermore, it is reported that the excessive overtriage results in greater burdens on the major trauma centres and underutilisation of community hospitals participating in the regional system.7 Several studies have shown that the reduction of overtriage using two-tiered or three-tiered trauma response systems decrease both the expenses and time consumption of trauma care significantly, while maintaining a high level of trauma care with minimal undertriage.17,6,16,20,18,4 In order to reduce overtriage in our setting and minimise undertriage, we developed an in-hospital triage tool based on a reduction of the trauma team (downgrading) rather than an upgrade-system. The in-hospital triage is applied by the full trauma team
P.H.P. Fung Kon Jin et al. itself in our Level-I trauma centre and the full resources of the trauma team are only continued when needed, while at the same time ensuring that potentially serious injuries are not overlooked nor inadequately treated. The application of a downgrading system rather than an upgrading system was considered a safer approach for our institution, infrastructure, and regional trauma organisation. We hypothesised that using this triage with a downgrading-system, a significant reduction of overtriage could be established without increasing undertriage or otherwise affecting patient care negatively. This study will evaluate the implementation of the AMC downgrading criteria protocol and the effect on both overtriage rates and outcome of the admitted trauma patients.
Patients and methods Study setting The Northwest-Netherlands Trauma Center is one of the 10 designated Level-1 trauma centres in the Netherlands, constituted by the two university hospitals in Amsterdam, and covers approximately 2.7 million inhabitants. The Academic Medical Center (AMC) is one of these two hospitals and is responsible for its part of the 1200 trauma victims that are distributed over the Northwest-Netherlands Trauma Center. The AMC trauma team sees approximately 600 emergency trauma patients per year, of which roughly 25% have an injury severity score (ISS) of 16 or higher. All these trauma patients are initially seen by the entire trauma team in one of the two trauma resuscitation rooms (shockrooms) available in the Emergency Department (ED), one of which is equipped with an overhead X-ray installation and an adjacent radiology viewing area. The decision for a patient to be transported to a Level-1 trauma centre is currently based on the triage and expertise of the prehospital Emergency
Table 1 Members of initial (full) and ‘downgraded’ Trauma Teams Initial (full) Trauma Team members Trauma Surgeon (ATLS certified) General Surgery Senior Resident (ATLS certified) General Surgery Junior Resident Anaesthesia Physician/Senior Resident Anaesthesia Nurse Radiologist/Senior Resident Radiology Technician (2) Trauma Nurse (2) Neurologist/Senior Resident (Neuro Trauma)
Downgraded Trauma Team members General Surgery Resident (ATLS certified)
Radiologist/Senior Resident Radiology Technician (2) Trauma Nurse (1)
The table shows the members for both the initial and downgraded Trauma Team. ATLS: advanced trauma life support.
In-hospital downgrading of the trauma team Medical Services personnel, following the PHTLSprogram.15 Based on their initial evaluation, the ED of the closest available trauma centre of the appropriate level as stated in the ambulance transport protocols is notified of the incoming Shockroom patient. In our centre, the entire trauma team is then notified through the in-hospital pager system. In Table 1, the composition of the trauma team is shown. All patients are examined and treated according to the ATLS-protocol as defined by the American College of Surgeons in 1997.1 Prior to the introduction of this protocol, the trauma team was not defined. In January 2002, the main shockroom was equipped with a video registration system after legal approval was obtained. On each arrival of a patient in the shockroom this registration is started.
Study design This study was conducted between 1st July 2002 and 31st December 2002, by means of a prospective study supported with video registration. All patients that were initially identified by the prehospital ambulance services as a ‘shockroom’ trauma in need of the trauma team were prospectively entered into the study. Patients 15 years or younger were excluded from the study. The other exclusion criteria were incomplete video registration, incomplete data collection or patients not transported by ambulance. Prior to the data collection, a list of physical and anatomical findings that would determine the need for a complete trauma team was assembled based on the current available literature.3,13,6,16,9,1,12,18,2, 15,19 These criteria were used to derive the downgrading flow chart (DFC) (Table 2). The result of the first AP chest X-ray was included in the DFC. With the presence of one or more positive criteria, the need for a full trauma team was deemed necessary. All criteria that were chosen for the DFC are obtained during the primary survey and after the first chest X-ray. If none of the criteria in the DFC was positive, the trauma team would immediately be reduced to the reduced (downgraded) trauma team (Table 1). The downgraded trauma team would proceed following the ATLS-protocol and treat the patient accordingly. At any time, if the status of the patient deteriorates, or the secondary survey reveals parameters that would retrospectively preclude the possibility of downgrading, or the patient requires the attention of the entire trauma team, the trauma team would be upgraded to its original composition immediately, using the in-hospital pager system. When downgrading was not indicated based on the downgrading criteria,
35 the trauma team would remain intact and treat the patient following the standard ATLS-protocol and all other standard operating procedures and policies as performed prior to this study and all attending team members stay in the Shockroom until the patient is transferred. Demographic and clinical data were collected for all patients and entered into a database. Demographic data included mechanism of trauma, age, gender, and injury severity score (ISS). With respect Table 2 ‘Downgrading’ criteria used for maintaining initial Trauma Team Airway A1: A2: A3: A4:
criteria (Impending) Airway obstruction Severe maxillofacial injury Risk of aspiration (bleeding, vomiting) Facial burn/inhalation trauma
Breathing criteria B1: Respiratory rate <10/min or >30/min Thoracic Injury: B2: Flail chest B3: Tension pneumothorax B4: Open pneumothorax B5: Chest X-ray with injury (except simple pneumothorax or <3 costal fractures for costae 4—9) Circulation criteria C1: Shock (systolic BP 90 mm Hg, pulse >120/min or < 50/min C2: Penetrating injuries to head, neck, thorax, abdomen and/or pelvic area C3: Abdominal tenderness C4: Hypothermia (T <328C) Burns: C5: Second and third degree burns >20% of body surface area C6: Second and third degree burns >10% of body surface area (age > 50) C7: Electrical burns Disability criteria D1: GCS <14 D2: Abnormal pupils D3: (Signs of) Spinal cord injury with neurological impairment D4: (Signs of) Basal skull fracture Exposure criteria E1: Unstable or open pelvic fracture E2: Two or more proximal long-bone fractures E3: Traumatic amputation above knee or above elbow E4: Penetrating injury proximal to knee or elbow The table shows the criteria used for maintaining the full, initial, trauma team. At least one positive criterion after the primary survey and first successful chest X-ray requires the full trauma team to stay intact, while the absence of all criteria leads to the reduced trauma team.
36 to the downgrading protocol, patients were classified into two groups: all patients that were treated by the complete trauma team were classified as ‘full team’ trauma patients, while patients that were treated by the reduced trauma team were designated ‘downgraded’ trauma patients. To determine the correct appliance of the downgrading protocol, each patient was analysed using the video registration and then categorised into the groups labelled ‘according to protocol’ (ATP) or ‘violation of protocol’ (VOP) based on whether the protocol was followed as instructed or not. To determine the safety of the protocol, a number of primary outcome criteria were defined (Table 3). The primary outcome criteria included mortality due to trauma, emergency procedures performed during initial evaluation, emergency surgical operations performed after initial evaluation in the shockroom, and type of ward to where patients were initially transferred (Table 3). All patients that had at least one of the primary outcome criteria were defined as ‘severely injured trauma patients’, while patients that did not meet at least one of the primary outcome criteria were deemed ‘not severely injured trauma patients’. All patients that were defined as ‘severely injured’ while treated by the downgraded trauma team, were considered ‘undertriaged’ trauma patients, while patients that were classified as ‘not severely injured’ and treated by the full trauma team were classified as ‘overtriaged’. Table 3 Primary outcome criteria for a severely injured patient Emergency procedure within 2 h of Admission Intubation or surgical airway Chest tube insertion Needle thoracocenthesis Pericardiocenthesis
P.H.P. Fung Kon Jin et al.
Statistical analysis Data were analysed for all eligible, included patients. All continuous variables are presented as mean S.D., and analysed using either the independent t-test with 95% confidence intervals or the Mann—Whitney U-test depending on the distribution. Categorical variables are calculated as percentage of frequency of occurrence. Discrete variables were compared using x2 analyses. Statistical significance was declared at the 0.05 level. All data management and statistical analyses were performed on a personal computer using both SPSS Data Entry Builder and SPSS Data Entry Station version 3.03, and SPSS Base for Windows, version 11.5, respectively (SPSS Inc., Chicago, IL).
Results Demographics Between 1st July and 31st December, a total of 254 consecutive trauma patients were admitted to the shockroom of the AMC. From this cohort, 220 patients were included in the study with a complete video registration and 16 years or older (Fig. 1). Of the 34 excluded patients, 24 patients did not meet the age criterion and 10 patients had an incomplete data collection. The mean age for the study group was 39.0 15.6 years with 148 (67.3%) male patients (Table 4). The female patients were significantly older (42.3 versus 37.4 years) than the male patients ( p < 0.05). Twenty-four patients (10.9%) were admitted due to penetrating injuries, and 51 (23.2%) patients were admitted with an ISS of 16 or higher.
Downgrading Emergency surgery within 2 h of admission Thoracotomy Laparotomy Craniotomy Surgical decompression spinal cord Amputation/revascularisation External fixation of pelvic fracture Fixation of 2 proximal long bone fractures Intensive Care Unit admission within 24 h Death within 48 h due to traumatic injury The table shows the criteria that have been used to define the seriously injured trauma patient for the study. All patients that meet at least one of the above mentioned criteria are designated as a severely injured patient that should be treated by the full Trauma Team.
In 95 (43.2%) cases, the trauma team was reduced after completing the DFC (Fig. 1). The median ISS value for the downgraded group was 1, with a range from 1 to 17. After downgrading it was never necessary to restore the trauma team to its original composition. Of the 95 downgraded trauma patients, 93 were downgraded according to the downgrading protocol having no positive criteria, while two cases were downgraded despite having one positive criterion (Table 5). The mean time necessary for the full trauma team to be reduced to the downgraded trauma team was 12 6 min. Of the two incorrectly downgraded patients, patient I (Male, 21 year, ISS 1) was haemodynami-
In-hospital downgrading of the trauma team
37
Fig. 1 This figure shows the complete study population, including the excluded patients. The patients that were included are divided in downgraded trauma team patients and full trauma team patients. These groups are further divided in subgroups, based on whether protocol was followed correctly. ATP: According to protocol, VOP: violation of protocol.
cally stable and showed no signs of injuries on the chest X-ray after falling through a glass door. The patient was released from the hospital without complications after the results of the second chest X-ray. Patient II (Male, 39 year, ISS 10) was alert and haemodynamically stable during the initial resuscitation phase following an abdominal stab wound, did not show signs of abdominal tenderness, and Focused Assessment with Sonography (FAST) was
negative for abdominal bleeding. After 12 h of observation, the patient showed signs of abdominal tenderness and shock, and required laparotomy for a perforation of his stomach and serosal injury of the transverse colon. He was released after 7 days without further complications. Both patients should have been treated by the full trauma team based on the presence of a penetrating injury proximal of the knees and elbows.
Table 4 Demographics Group (n)
Median ISS (range)
ISS 16 (%)
Mean hospital stay (days)
Gender (% male)
Study population (220) Downgraded patients (95) Full Team patients (125) Downgraded ATP (93) Full Team patients ATP (104) Severely injured patients (66) Non-severely injured patients (154)
5 1 9 1 13 20 1
51 2 49 2 49 45 6
7.2 12.3 3.1 6.3 10.3 14.6 3.1 6.4 11.4 15.5 3.7 7.1 15.3 17.1
67.3 58.9 73.6 58.1 77.9 74.2 64.3
(1—66) (1—10) (1—66) (1—17) (1—66) (4—66) (1—38)
(23.2) (2.1) (39.2) (2.2) (47.1) (68.2) (3.9)
The table shows the demographics for the study population and the defined subgroups. ATP: according to protocol.
Table 5 Criteria for maintaining the full Trauma Team Positive criteria
Downgraded patients n = 95 (%)
Full Team patients n = 125 (%)
Total n = 220 (%)
0 1 2 3
93 2 0 0
22 55 22 26
115 57 22 26
(97.9) (2.1) (0) (0)
(17.6) (44.0) (17.6) (20.8)
(52.3) (25.9) (10.0) (11.8)
This table shows the number of positive downgrading criteria found for the entire study population, the downgraded patients, and the Full Team patients.
38
P.H.P. Fung Kon Jin et al.
Table 6 Primary outcome criteria Outcome criterion
Downgraded patients n = 95 (%)
Full Team patients n = 125 (%)
Total n = 220 (%)
Death < 48 h Emergency surgery <2 h Intensive Care Unit admission Emergency Procedure < 2 h Severely injured patients Total surgical interventions Total mortality
0 (0) 0 (0) 0 (0) 0 (0) 0 (0) 15 (15.8) 0 (0)
10 24 72 34 66 56 15
10 24 72 34 66 71 15
(8.0) (19.2) (57.6) (27.2) (52.8) (44.8) (12.0)
(4.5) (10.9) (32.7) (15.5) (30.0) (32.3) (6.8)
The table shows the primary outcome criteria for the entire study population, the downgraded patients, and the full team patients. In addition, also included in this table are the total number of patients undergoing surgical interventions and total mortality found.
The remaining 125 patients were treated by the full trauma team. The median ISS for the patients treated by the full trauma team was 9, ranging from 1 to 66. In 21 patients however, no positive criteria were present and the downgrading protocol was violated (median ISS 4, range 1—14). For the remaining 104 patients, the trauma team remained complete in accordance with the protocol, diagnosed with one or more positive criteria (Table 5).
Primary outcome A summary of the primary outcome for all four subgroups can be found in Table 6. Sixty-six (30.0%) of the patients met at least one of the criteria classifying a severe injured patient. Mean ISS for this group was 21.9 13.3. The overall mortality of the included study group was 6.6% (n = 15). One of the 15 deceased patients died unrelated to a traumatic injury (myocardial infarction). The remaining 14 patients died or were pronounced brain dead within 8 days of the accident. A total of 71 patients were operated upon, including three post-mortem for organ donation. Of the remaining 68 operated patients, 24 patients underwent emergency surgical interventions as described in Table 3. None of these 24 patients were treated by a downgraded Trauma Team. There were a total of 72 admissions to the Intensive Care Unit. The mean hospital stay for downgraded patients (3.0 days) was significantly shorter than for the full team patients (9.9 days) ( p < 0.001).
Discussion This study investigated if downgrading of the trauma team using the AMC downgrading criteria is a safe way to reduce overtriage of trauma victims, without negatively influencing patient outcome. The current
organisation for trauma care on both the regional and institutional level requires our centre to have the entire trauma team present when the patient arrives at the shockroom, in order to guarantee the optimal level of trauma care as described by the ACS/COT.1,2 The study results suggest that an accurate selection is made by the AMC downgrading protocol based on the physiologic and anatomic data collected during the primary survey, leading to a significant reduction of overtriage without a case of undertriage. The fact that there has been no undertriage also implies that no extra criterion is needed. It is interesting to note that the addition of the first conventional chest X-ray results as a selection criterion was the main reason why nine severely injured patients were not missed: the full trauma team was maintained based purely on the results from the chest X-ray for 11 patients. Of these 11 patients, 9 were classified as severely injured, while 2 were overtriaged by the chest X-ray criterion. The overall overtriage rate that remains present after implementation of the AMC downgrading criteria is approximately 27% of all shockroom patients. While this number still seems high, one has to keep in mind that prior to the study and implementation, all downgraded patients would have been treated by the complete trauma team, which would have led to 153 overtriaged patients (69.5%). Also when analysing the implementation of the downgrading protocol, a significant learning curve was noted. Most of the patients that should have been downgraded but due to protocol violation were kept in the full team patients group, were seen in the first two months of the study. With the reduction of this group, the overtriage rate would have decreased even more. A possible improvement of the AMC downgrading criteria might be an adjustment for the penetrating injury criterion. Evaluation of the patients in the full team group with just one positive criterion shows that the least specific criterion is that of penetrating
In-hospital downgrading of the trauma team injuries. However, although this criterion shows a significant number of overtriaged patients, it cannot be overlooked that the criterion also identified several patients with penetrating injuries were severely injured and required immediate attention of the multidisciplinary trauma team. Furthermore, the two protocol violations that were downgraded despite having one positive criterion on the DFC, both had sharp injury proximal to the knees and elbows. When reviewing the patient with the sharp injury to the back after falling through a glass window, it seems reasonable that a superficial cut without deep penetration and no injury on the chest X-ray does not require the full trauma team. However, with the current downgrading criteria, no difference is made between a superficial penetrating injury proximal to the knees and elbows, and a deep penetrating sharp injury. Strictly speaking, this patient should have been treated by the full team. A possible solution is a more accurate description for the sharp injuries to neck, thorax, abdomen, and groin that require the full trauma team, or a combination of criteria in case of a sharp injury, in an attempt to reduce the overtriage due to the penetrating injury criterion. The composition of our trauma team does not comprise medical specialists who are solely available for the trauma team. Therefore, these people are interrupted in their clinical activities to form the trauma team for each pre-notification of a shockroom patient. This leads to delays in several departments (including operating rooms), from the moment the trauma pager is activated until the team member can return to his/her previous activity. In the clinical setting prior to the AMC downgrading protocol, the moment for each member to return to their original post remained unclear and resulted in a mismanagement of valuable people and resources. With the introduction of the downgrading protocol, an attempt is made not only to create a clear guideline for each trauma team member, but also to stimulate a more efficient working environment. A recent study at our centre evaluated the impact of the trauma team patients on the Emergency Department’s efficiency based on a theoretical management model and described the beneficiary effect of the early return of one of the two trauma nurses to the Emergency Department.11 Although no exact data are available on the effect of the downgrading protocol on other in-hospital departments, it can be assumed that the early and structured return of trauma team members to their prior activities can only contribute to hospital efficiency and eventually, patient care.
39 While the expertise in the prehospital setting, along with the communication between the prehospital services and the in-hospital trauma care clearly show signs of improvement, not every trauma centre is currently suited to reduce overtriage by using a two- or three-tiered trauma response.5 Although several studies have shown that a two-tiered trauma response system can further decrease overtriage rates, the same studies have also shown an increase in undertriage rates, albeit minor.4,6,7,16—18,20 Ryan et al. showed that using a two-tier triage system, their overtriage rates dropped to 10%. However, they also reported 8% undertriage of patients.18 While we acknowledge that our system is still far from perfect, the fact that we were able to reduce overtriage without any undertriage can have a significant impact on all centres that are in a similar situation as ours. Even renowned centres that use two- or three-tiered trauma response systems could benefit from applying our tool to further reduce overtriage using evidence based medicine. Using the physiological and anatomical criteria as used in the downgrading protocol a quick and accurate assessment can be made to determine whether the patient will benefit from the initial, full trauma team. With this study, we have demonstrated that the AMC downgrading protocol is a safe and effective way for reducing overtriage in our institution.
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