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A novel diversion protocol dramatically reduces diversion hours
American Journal of Emergency Medicine (2008) 26, 670–675
www.elsevier.com/locate/ajem
Original Contribution
A novel diversion protocol dramatically reduces diversion hours☆ Osei Kwame Asamoah MD, PhD, Steven J. Weiss MD⁎, Amy A. Ernst MD, Michael Richards MD, David P. Sklar MD Department of Emergency Medicine, University of New Mexico, Albuquerque, NM 87131-0001, USA Received 31 August 2007; revised 1 October 2007; accepted 12 October 2007
Abstract Introduction: Ambulance diversion is a problem in many communities. When patients are diverted prompt and appropriate medical care may be delayed. Objective: Compare diversion hours and drop-off times before and after a dramatic change in diversion policy restricting each hospital to 1 hour out of every 8. Methods: This study was a retrospective study in a county of 600 000 people and 10 hospitals from September 2004 to February 2006. A countywide diversion protocol was implemented in March 2005 that limited diversion hours to 1 hour out of every 8 (maximum of 90 h/mo). No other changes were implemented during the study period. Pretrial (9/04-2/05), interim (3/05-8/05), and posttrial (9/05-2/06) periods were compared. The main outcome measures were ambulance diversion hours and emergency medical service (EMS) drop-off times. Results were compared using analysis of variance and a Tukey post hoc analysis. P b .05 was considered significant. Results: There was no significant difference in the number of monthly transports comparing the posttrial vs pretrial periods; however, a significant decrease in monthly ambulance diversion hours (difference, 251 hours; 95% CI, 136-368) and significant increase in additional time that EMS crews required to transport patients (drop-off times) (difference, 178 hours; 95% CI, 74-283) were observed. Posttrial diversion hours decreased to 18% of the pretrial values (from 305 to 54). Conclusion: This novel ambulance diversion protocol dramatically reduced diversion hours at the cost of increasing EMS drop-off times in a large community. © 2008 Elsevier Inc. All rights reserved.
1. Introduction Emergency department crowding has become an increasingly important issue capturing the public's attention as illustrated by a number of articles in the popular press [1-3]. This phenomenon was forecasted by emergency physicians Presented at SAEM, May 2007, Chicago, Ill. Funded in part by the Valente Foundation. ⁎ Corresponding author. Tel.: +1 505 272 5062; fax: +1 505 272 6503. E-mail address: [email protected] (S.J. Weiss).
☆
0735-6757/$ – see front matter © 2008 Elsevier Inc. All rights reserved. doi:10.1016/j.ajem.2007.10.020
over a decade ago [4-8] and continues to be an area of avid interest in the ED community [9-14]. In June 2006, the Institute of Medicine (IOM) published a series of reports on the current state and future vision of emergency care [15-17]. Ambulance diversion is a common method that EDs use to limit patient demand when departmental resources are extended beyond the limit of patient safety. In many metropolitan regions, ambulance diversion has grown to epidemic proportions as detailed by Patel et al [18] who described greater than 2000 h/mo of diversion time in Sacramento in 1992. In theory, the temporary closure of an
A novel diversion protocol dramatically reduces diversion hours ED to ambulance traffic allows EDs to more effectively manage their present patient load. Unfortunately, this action causes a disproportionate flow of ambulance traffic to the nearest facility resulting in subsequent ambulance diversion in a reciprocal manner. This has been described as the oscillating phenomenon [19] and places undue strain on the prehospital providers who must navigate patients within this erratic network of hospitals. Ambulance diversion may not successfully solve the ED overcrowding problem. In fact, Khaleghi et al [20] were able to show that minimizing diversion hours would have little effect on system crowding. Instead of improving ED overcrowding, ambulance diversion due to ED closure has resulted in a variety of problems that may compromise patient care. For instance, emergency medical service (EMS) providers must frequently travel longer distances, bypassing closer facilities, to find an “open” ED. Upon arrival, many EDs are so congested that paramedics are required to monitor their patients for extended periods until the ED staff is able to assume patient care. As a result, paramedics are caring for critically ill patients for prolonged periods further burdening the prehospital system as fewer EMS responders are available for new 911 calls. Not surprisingly, ambulance diversion has been linked to increased patient morbidity and mortality [9,21-26], although a recent review does not substantiate this association [27]. Diversion also leads to delays by sending a patient to a facility where that patient would not normally go, instead of to the facility with their records and personal physician. Not only does ambulance diversion not improve ED overcrowding, but it also imparts further burdens on the prehospital system. Recent studies have shown impact on financial returns for the ED and hospital, and on trauma systems [28,29]. To respond to the problems related to ambulance diversion, we developed a countywide EMS protocol to limit the amount of diversion time each hospital could request. One hour was chosen for this initiative to keep total diversions under 90 h/mo (which our committee believed to be reasonable) while allowing 1 hour for each ED to reassess its resources and needs when necessary. Before the protocol, hospitals could go on divert at any time and stay on divert until they actively went off divert, unless more than 3 hospitals were on divert at the same time, at which point they would all be forced off divert and forced open. This approach yielded several unfortunate results. At times, hospitals would go on divert and forget to take themselves off divert resulting in many more hours of divert than necessary. Also, when a hospital went on divert and other area hospitals began to experience increased ambulance flow, the other hospitals could quickly force the first hospital off divert and prevent it from having any opportunity to decompress an unsafe situation. The protocol was instituted to guarantee a 1-hour breather for the overloaded hospital but to limit this to no more than 1 hour out of 8. The objective of this study was to ascertain the effect of that protocol on ambulance diversion hours and patient dropoff times. We hypothesized that this countywide EMS
671
protocol which limited ED diversion would be associated with a significant decrease in ambulance diversion and a concomitant increase in EMS drop-off times in the ED.
2. Materials and methods Because of the problems associated with diversion, a new countywide EMS protocol limited the time that EDs were on diversion to 1 hour after which time they were forced open for the subsequent 8 hours. This protocol restricted total diversion time for any given ED to 3 h/d or approximately 90 h/mo. The decision to trigger ambulance diversion was determined by the attending physician and nursing supervisor based on the degree of overcrowding (ie, perception of inadequate resources to meet patient demand) with no established countywide standards. The implementation of the protocol began in March 2005. Emergency medical service units disregarded the ED status only for major trauma, which went to the trauma center. For the purpose of this study, EDs were categorized as either open (no ambulance diversions) or closed (ambulances diverted). With this type of protocol, we hoped the local system would deliver patients more equitably to their correct institution and the ambulances would be more available in the community for ongoing transports. This was a pre/postdesign study of a change in the local protocol for ambulance diversion. Our institutional review board approved the study. This study was conducted in a county with an area of approximately 1200 square miles and a population in excess of 625 000 people. The catchment area is geographically diverse, consisting of urban, suburban, and rural regions. Ten EDs including one level 1 trauma center serve this population. The EMS system in the study region has a 2-tiered structure in which fire fighters are first responders with basic and advanced life support skills and private contractors provide transportation to hospitals. Written protocols guide medical direction with supplemental directions provided by a hospital-based medical control physician, if necessary. EMS units transport patients to the closest hospital capable of appropriate treatment. Although major trauma is never diverted from the trauma center, diversion applies to all other ambulance patients. Patient requests are honored unless the requested receiving hospital is on diversion. Monthly data were collected from the local transport service continuous quality improvement reports consisting of the number of transports, the call acuity (eg, priority 1— emergent, priority 2—urgent), and the response, transport, and drop-off times. EMSystem (Milwaukee, Wis), an Internet-accessible network, provided real-time information regarding the operating status of EDs, intensive care units, and inpatient facilities of hospitals throughout the county. Comprehensive data for the operating status of all EDs in the county were collected from EMSystem during the pretrial (September 1,
672 2004, through February 28, 2005), interim (March 1, 2005, through August 31, 2005), and posttrial (September 1, 2005, through February 28, 2006) periods. The pre- and posttrial periods represented the same 6 months separated by 1 year. The interim period represented a retraining period that allowed hospitals to learn the new protocol for diversion. This study's primary outcome measure was the total monthly duration (in hours) of ambulance diversion during the pretrial, interim, and posttrial periods. Two secondary outcome measures were chosen because they are known correlates of EMS resource utilization. The first secondary outcome measure was the average drop-off time for 90% of patients (in minutes). Drop-off time represents the time it takes for EMS personnel to become available for service after arrival with a patient to an ED 90% of the time. The second secondary outcome measure was additional time over 15-minute allowance (in hours) during the study periods. As fifteen minutes is a standard allotted time for a drop-off in this system, any delay beyond this time represents a decrease in the number of available ambulances. Thus, additional unit hours per month = [(90% drop-off time − 15 minutes) × no. of transports]/60 minutes. Both of these were readily available from the participating EMSs.
2.1. Statistics Descriptive statistics were used for number of ambulance transports and for the primary outcome measures. Analysis of variance and a Tukey post hoc analysis were used to compare the difference in means between the pretrial, interim, and posttrial periods. A P value of less than .05 was considered significant.
3. Results There were a total of 73295 transports to the region's EDs during the study period. Table 1 (line 3) shows that the monthly average transports for the 3 periods were not significantly different. The adaptation of the diversion guidelines reduced mean monthly diversion hours from 305 to 54 hours (difference, 251 hours; 95% CI, 136-368) between the pretrial and posttrial periods (see Table 1). This corresponds to an 82% reduction in diversion hours during this period. Fig. 1 shows the number of ambulance diversion hours per month during the 3 study periods. During the interim period, a progressive reduction in the time EDs were closed to ambulance traffic is demonstrated. However, from the interim to posttrial period a dramatic decrease in ambulance diversion was noted consistent with EDs adhering to the new guidelines. Secondary outcomes are also illustrated in Table 1. The average percent time closed decreased from 4.7% to 0.8% (difference, 3.90%; 95% CI, 2.05-5.74) between the pretrial and posttrial study periods with a concomitant drop in
O.K. Asamoah et al. Table 1 Comparison of diversion measures during the consecutive thru 6-month periods of the study (pretrial, interim, and posttrial) Pretrial
Interim period
Posttrial
Systemwide Monthly duration 305 ± 102 275 ± 85 54 ± 15 ⁎ of ambulance diversion (h) Average % of 4.7 ± 1.7 4.2 ± 1.3 0.8 ± 0.2 ⁎ time closed Number of monthly 3960 ± 162 4167 ± 147 4089 ± 216 transports Average 90% drop- 21.1 ± 1.2 22.5 ± 0.5 ⁎ 22.8 ± 0.9 ⁎ off time (min) Additional unit 559 ± 96 722 ± 44 ⁎ 738 ± 56 ⁎ time (h) Major trauma center only 61 ± 10 53 ± 12 11 ± 4 ⁎ Monthly duration of ambulance diversion (h) 8.4 ± 1.4 7.3 ± 1.5 1.6 ± 0.5 ⁎ Average % of time trauma center closed Number of monthly 1095 ± 47 1184 ± 37 ⁎ 1165 ± 100 transports Average 90% drop- 30.27 ± 0.1 30.55 ± 0.2 ⁎ 30.54 ± 0.1 ⁎ off time (min) Additional unit 278 ± 13 307 ± 14 ⁎ 302 ± 25 ⁎ time (h) ⁎ P b .05.
time closed at the major trauma center. There was a significant increase in the average drop-off time (difference, +1.66 min/mo; 95% CI, 0.33-2.98), and additional unit time (difference, +178 h/mo; 95% CI, 74-283 hours) when comparing pretrial and posttrial periods. We were also determined that this novel diversion protocol had a similar effect on diversion statistics at the only level 1 trauma center in the system. As shown in Table 1 a substantial reduction in mean closed hours is observed in the posttrial period relative to the pretrial period (difference, −50 hours; 95% CI, 40-60). This represents an 82% reduction in closed hours at the level 1 trauma center or a significant decrease in percent closed time (difference, 6.8%; 95% CI, 5.5-8.2). A small but statistically significant increase in the 90% average drop-off time is noted at the trauma center between the pre- and posttrial periods (difference, 0.3 minutes; 95% CI, 0.1-0.5) with a parallel increase in additional unit hours (difference, 24 hours; 95% CI, 0.6-45.3).
3.1. Limitations and future directions This study has a number of limitations. It is a study over time and therefore can be biased by outside influences that
A novel diversion protocol dramatically reduces diversion hours
673
This study only represents the results of 1 system and may not have external validity. Emergency medical systems that do not have the same operational characteristics as ours may respond quite differently to such a diversion protocol. This is just the beginning stages of an experiment in our community to decrease diversion and improve EMS drop times. In the future we will look at the longer term consequences and changes required to continue to manage the system in the best possible manner.
4. Discussion
Fig. 1 Graph of the changes that occurred over time in the pre-, interim, and post-trial periods. The dramatic decrease can be seen in the changes over time. The 3 trial periods, each 6 months in length, were the pretrial (September 1, 2004, through February 28, 2005), the interim (March 1, 2005, through August 31, 2005), and the posttrial (September 1, 2005, through February 28, 2006) periods. The pre- and posttrial periods represented the same 6 months separated by 1 year. The interim period represented a retraining period that allowed hospitals to learn the new diversion protocol.
occurred during the study period of which we were not aware. As ED overcrowding has become worse over time, we would have expected an increase in some of the variables collected, not a decrease. Thus, we believe that the changes noted in this study are a result of the protocol-based intervention within the EMS system. Statistically, the analysis of variance does not address the relationship between time points. If we had access to software that analyzed time series using an autoregressive integrated moving average model, it may have been a clearer reflection of the results. We are unable to specifically temporally quantify the system overcrowding; however, the trauma center ED census did not change during the study period suggesting no change in overcrowding. This does not take into account the possibility that the severity of illness of our patients was changing. Another limitation is that we did not look at patient data in terms of changes in morbidity and mortality. Patientcentered outcomes, although more difficult to obtain, would have strengthened the argument for or against this new policy. The only suggestion of improvement that we obtained was that patients were reaching their destination of choice and hospital with their medical records. We can speculate that this improved overall care. Another area in which improvement could be documented is on the financial impact to each hospital and to the system. These data were not available to the investigators but were the impetus for the changes reported. Hospitals felt that their patients being diverted to other hospitals was having a detrimental effect on their budget.
Emergency department personnel are acutely aware of crowding issues and ensuing ambulance diversion. Capacity problems are a routine part of clinical practice in many EDs that have recently garnered federal attention. In their series of reports [15-17] on the current state and future vision of emergency care, the IOM put forth several recommendations to mitigate ED crowding. However, until the ED community, hospital administrators, and policymakers are able to find effective solutions for the current crisis, ambulance diversion will continue to be a natural response to reduce patient influx and reestablish equilibrium between limited ED resources and apparently unlimited patient demand. We chose the solution of simply removing diversions from our system, except in rare circumstances. Decrease diversion has been shown to be of benefit to all hospitals systems [30]. The basis for overcrowding is complex and can be linked to a number of interwoven factors. These can include “boarding” admitted patients [8], nursing staff shortages, decreased access to primary care [7], and an absolute decrease in the total number of EDs in the face of increasing demand [31]. Irrespective of the underlying basis of ED crowding, the result is decreased patient throughput, fewer available ED beds, and stretchers lining hallways. Emergency department closure to incoming ambulance traffic is, theoretically, a tool that should be used on rare occasions when patient safety is truly compromised. This strategy temporarily alleviates “front end” pressure enabling limited ED resources to be focused on patients who are in the ED. Elimination of ambulance diversion can only effectively be realized through changes in hospital and ED processes. However, overuse of diversion can be mitigated by countywide protocols as successfully used in San Diego, California [32]. This study demonstrates a significant reduction of ambulance diversion in a heterogeneous county composed of urban, suburban, and rural regions. Our study confirms that a strict protocol regulating the duration of time an individual ED can be closed to ambulance traffic yields clear improvement in measurable outcomes. However, successful ambulance diversion is contingent upon collaboration of all EDs in the network and adherence by prehospital providers. This county was successful in decreasing ambulance
674 diversion by 82% during the posttrial period. This actually required less system effort than was described by Patel et al [18] in the Sacramento system. The primary difficulty we found in instituting this protocol was political. Hospitals were concerned about their inability to take care of the influx of patients that the protocol would cause. However, this was overridden by the significant belief that it was a disservice to the patients to be taking them to hospitals that did not know them or have their records, only to return them to their own hospital at a later time. The protocol was so successful that it is still in effect more than 1 year after the termination of the study. We believe that this dramatic reduction in diversion throughout the county allowed EMS personnel to more easily transport patients to the closest appropriate facility and maximized the opportunity for patient transport to a hospital of his/her choice. We believe that an effort to decrease diversion was of benefit to all of the hospitals in our system. Multiple communities have addressed the issue of ED crowding and have sought different methods to reduce ambulance diversion. For example, Lagoe et al [33] describe the implementation of an Internet-based EMS software system that provided real-time ED closure data and facilitated a cooperative effort to reduce community-wide ambulance diversion in Syracuse, New York. Although impressive reduction in diversion hours was found during the study period, this was accomplished through each individual hospital implementing its own measures to limit closures rather than establishing multi-hospital protocols. This study represents the third report of an attempt to decrease diversion through area-wide protocol. San Diego County also undertook measures to decrease ambulance diversion. Vilke et al [19] describe a community-wide intervention in which each hospital could only go on diversion for 1 hour, after which it had to receive at least 1 ambulance patient before returning to diversion status. In the San Diego protocol, they required hospitals to take their own patients even if on diversion. The authors report a dramatic 73% reduction in diversion hours during the trial period and a small subsequent increase of 17% diversion hours from the trial to posttrial period. Like the present study, there was minimal change in the number of runs/month during the study period. Although the authors admit that relaxed scrutiny of the diversion protocol may be a contributing factor, they did not anticipate a return to preintervention diversion hours. Another community-based approach to ambulance diversion was adapted in the Sacramento metropolitan area [18]. Sacramento implemented a policy that allowed each hospital to close for no more than 3 hours before opening and remaining open for at least 1 hour. This study also resulted in a 74% decrease in diversion hours from the preintervention to the postintervention period. Although this reduction in diversion hours was quite impressive, the ability for a facility to divert ambulances for 3 consecutive hours could adversely affect nearby EDs and the EMS system. The study covered a 3-year period during which the area population, the number
O.K. Asamoah et al. of ED visits, and the number of EMS runs all increased dramatically. Neither Sacramento nor San Diego looked at the adverse effect of ambulance diversion changes on drop times for the EMS. In theory, ambulance diversion is a tool used only when patient safety would be compromised by the addition of another ambulance patient. In this scenario, a sustained reduction in ambulance diversion could only be realized through changes in internal hospital processes that optimize patient disposition to an inpatient bed or discharge from the ED. Our data support this notion. The remarkable reduction of ambulance diversion hours in this study was accompanied by a 32% increase in additional monthly drop-off hours in the overall system. Transfer of patient care was likely prolonged owing to lack of available space to accommodate another stretcher. In fact, there is a nationwide trend of EMS crews detained at hospitals upwards of several hours [34,35]. Accordingly, paramedics are not available for the next potential critical call.
5. Conclusion A coordinated effort to minimize ambulance diversion was successful in a large community composed of urban, suburban, and rural populations. Although the dramatic reduction in diversion hours facilitates patient transport to the nearest ED or hospital of first choice, the increased EMS drop-off time may compromise the 911-response system. This is the first study to consider the impact of overcrowding on ambulance drop times. The decrease in diversions may negatively impact ambulance services which have to wait longer to drop-off patients at crowded facilities.
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A novel diversion protocol dramatically reduces diversion hours [10] Schull MJ, Kiss A, Szalai JP. The effect of low-complexity patients on emergency department waiting times. Ann Emerg Med 2007;49(3): 257-64, 264.e1. [11] Atzema C, Bandiera G, Schull MJ. Emergency department crowding: the effect on resident education. Ann Emerg Med 2005; 45(3):276-81. [12] Asplin BR, Magid DJ. If you want to fix crowding, start by fixing your hospital. Ann Emerg Med 2007;49(3):273-4. [13] Asplin BR, Flottemesch TJ, Gordon BD. Developing models for patient flow and daily surge capacity research. Acad Emerg Med 2006;13(11):1109-13. [14] Bernstein SL, Asplin BR. Emergency department crowding: old problem, new solutions. Emerg Med Clin North Am 2006;24(4): 821-37. [15] Institute of Medicine Committee on the Future of Emergency Care in the US Health System. Hospital-based emergency care: at the breaking point. Washington (DC): National Academies Press; 2006. [16] Institute of Medicine Committee on the Future of Emergency Care in the US Health System. Emergency medical services: at the crossroads. Washington (DC): National Academies Press; 2006. [17] Institute of Medicine Committee on the Future of Emergency Care in the US Health System. Emergency care for children: growing pains. Washington (DC): National Academies Press; 2006. [18] Patel PB, Derlet RW, Vinson DR, Williams M, Wills J. Ambulance diversion reduction: the Sacramento solution. Am J Emerg Med 2006;24(2):206-13. [19] Vilke GM, Brown L, Skogland P, Simmons C, Guss DA. Approach to decreasing emergency department ambulance diversion hours. J Emerg Med 2004;26(2):189-92. [20] Khaleghi M, Loh A, Vroman D, Chan TC, Vilke GM. The effects of minimizing ambulance diversion hours on emergency departments. J Emerg Med 2007;33(2):155-9. [21] Asplin BR. Does ambulance diversion matter? Ann Emerg Med 2003;41(4):477-80. [22] Schull MJ, Morrison LJ, Vermeulen M, Redelmeier DA. Emergency department overcrowding and ambulance transport delays for patients with chest pain. CMAJ 2003;168(3):277-83. [23] Upfold J. Emergency department overcrowding: ambulance diversion and the legal duty to care. CMAJ 2002;166(4):445-6.
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[24] Redelmeier DA, Blair PJ, Collins WE. No place to unload: a preliminary analysis of the prevalence, risk factors, and consequences of ambulance diversion. Ann Emerg Med 1994;23(1):43-7. [25] Schull MJ, Morrison LJ, Vermeulen M, Redelmeier DA. Emergency department gridlock and out-of-hospital delays for cardiac patients. Acad Emerg Med 2003;10(7):709-16. [26] Hwang U, Richardson LD, Sonuyi TO, Morrison RS. The effect of emergency department crowding on the management of pain in older adults with hip fracture. J Am Geriatr Soc 2006;54(2):270-5. [27] Pham JC, Patel R, Millin MG, Kirsch TD, Chanmugam A. The effects of ambulance diversion: a comprehensive review. Acad Emerg Med 2006;13(11):1220-7. [28] Millin MG, Hedges JR, Bass RR. The effect of ambulance diversions on the development of trauma systems. Prehosp Emerg Care 2006;10 (3):351-4. [29] Falvo T, Grove L, Stachura R, Zirkin W. The financial impact of ambulance diversions and patient elopements. Acad Emerg Med 2007;14(1):58-62. [30] McConnell KJ, Richards CF, Daya M, Weathers CC, Lowe RA. Ambulance diversion and lost hospital revenues. Ann Emerg Med 2006;48(6):702-10. [31] American College of Emergency Physicians. Facts, statistics, and data. [Web Page]. Available at: http://www.acep.org/webportal/Newsroom/ NewsMediaResources/StatisticsData/default.htm (Accessed 2007 Mar 19). [32] Vilke GM, Castillo EM, Metz MA, Ray LU, Murrin PA, Lev R, et al. Community trial to decrease ambulance diversion hours: the San Diego county patient destination trial. Ann Emerg Med 2004;44(4): 295-303. [33] Lagoe RJ, Kohlbrenner JC, Hall LD, Roizen M, Nadle PA, Hunt RC. Reducing ambulance diversion: a multihospital approach. Prehosp Emerg Care 2003;7(1):99-108. [34] Eckstein M, Isaacs SM, Slovis CM, Kaufman BJ, Loflin JR, O'Connor RE, et al. Facilitating EMS turnaround intervals at hospitals in the face of receiving facility overcrowding. Prehosp Emerg Care 2005;9(3): 267-75. [35] Eckstein M, Chan LS. The effect of emergency department crowding on paramedic ambulance availability. Ann Emerg Med 2004;43(1): 100-5.
www.elsevier.com/locate/ajem
Original Contribution
A novel diversion protocol dramatically reduces diversion hours☆ Osei Kwame Asamoah MD, PhD, Steven J. Weiss MD⁎, Amy A. Ernst MD, Michael Richards MD, David P. Sklar MD Department of Emergency Medicine, University of New Mexico, Albuquerque, NM 87131-0001, USA Received 31 August 2007; revised 1 October 2007; accepted 12 October 2007
Abstract Introduction: Ambulance diversion is a problem in many communities. When patients are diverted prompt and appropriate medical care may be delayed. Objective: Compare diversion hours and drop-off times before and after a dramatic change in diversion policy restricting each hospital to 1 hour out of every 8. Methods: This study was a retrospective study in a county of 600 000 people and 10 hospitals from September 2004 to February 2006. A countywide diversion protocol was implemented in March 2005 that limited diversion hours to 1 hour out of every 8 (maximum of 90 h/mo). No other changes were implemented during the study period. Pretrial (9/04-2/05), interim (3/05-8/05), and posttrial (9/05-2/06) periods were compared. The main outcome measures were ambulance diversion hours and emergency medical service (EMS) drop-off times. Results were compared using analysis of variance and a Tukey post hoc analysis. P b .05 was considered significant. Results: There was no significant difference in the number of monthly transports comparing the posttrial vs pretrial periods; however, a significant decrease in monthly ambulance diversion hours (difference, 251 hours; 95% CI, 136-368) and significant increase in additional time that EMS crews required to transport patients (drop-off times) (difference, 178 hours; 95% CI, 74-283) were observed. Posttrial diversion hours decreased to 18% of the pretrial values (from 305 to 54). Conclusion: This novel ambulance diversion protocol dramatically reduced diversion hours at the cost of increasing EMS drop-off times in a large community. © 2008 Elsevier Inc. All rights reserved.
1. Introduction Emergency department crowding has become an increasingly important issue capturing the public's attention as illustrated by a number of articles in the popular press [1-3]. This phenomenon was forecasted by emergency physicians Presented at SAEM, May 2007, Chicago, Ill. Funded in part by the Valente Foundation. ⁎ Corresponding author. Tel.: +1 505 272 5062; fax: +1 505 272 6503. E-mail address: [email protected] (S.J. Weiss).
☆
0735-6757/$ – see front matter © 2008 Elsevier Inc. All rights reserved. doi:10.1016/j.ajem.2007.10.020
over a decade ago [4-8] and continues to be an area of avid interest in the ED community [9-14]. In June 2006, the Institute of Medicine (IOM) published a series of reports on the current state and future vision of emergency care [15-17]. Ambulance diversion is a common method that EDs use to limit patient demand when departmental resources are extended beyond the limit of patient safety. In many metropolitan regions, ambulance diversion has grown to epidemic proportions as detailed by Patel et al [18] who described greater than 2000 h/mo of diversion time in Sacramento in 1992. In theory, the temporary closure of an
A novel diversion protocol dramatically reduces diversion hours ED to ambulance traffic allows EDs to more effectively manage their present patient load. Unfortunately, this action causes a disproportionate flow of ambulance traffic to the nearest facility resulting in subsequent ambulance diversion in a reciprocal manner. This has been described as the oscillating phenomenon [19] and places undue strain on the prehospital providers who must navigate patients within this erratic network of hospitals. Ambulance diversion may not successfully solve the ED overcrowding problem. In fact, Khaleghi et al [20] were able to show that minimizing diversion hours would have little effect on system crowding. Instead of improving ED overcrowding, ambulance diversion due to ED closure has resulted in a variety of problems that may compromise patient care. For instance, emergency medical service (EMS) providers must frequently travel longer distances, bypassing closer facilities, to find an “open” ED. Upon arrival, many EDs are so congested that paramedics are required to monitor their patients for extended periods until the ED staff is able to assume patient care. As a result, paramedics are caring for critically ill patients for prolonged periods further burdening the prehospital system as fewer EMS responders are available for new 911 calls. Not surprisingly, ambulance diversion has been linked to increased patient morbidity and mortality [9,21-26], although a recent review does not substantiate this association [27]. Diversion also leads to delays by sending a patient to a facility where that patient would not normally go, instead of to the facility with their records and personal physician. Not only does ambulance diversion not improve ED overcrowding, but it also imparts further burdens on the prehospital system. Recent studies have shown impact on financial returns for the ED and hospital, and on trauma systems [28,29]. To respond to the problems related to ambulance diversion, we developed a countywide EMS protocol to limit the amount of diversion time each hospital could request. One hour was chosen for this initiative to keep total diversions under 90 h/mo (which our committee believed to be reasonable) while allowing 1 hour for each ED to reassess its resources and needs when necessary. Before the protocol, hospitals could go on divert at any time and stay on divert until they actively went off divert, unless more than 3 hospitals were on divert at the same time, at which point they would all be forced off divert and forced open. This approach yielded several unfortunate results. At times, hospitals would go on divert and forget to take themselves off divert resulting in many more hours of divert than necessary. Also, when a hospital went on divert and other area hospitals began to experience increased ambulance flow, the other hospitals could quickly force the first hospital off divert and prevent it from having any opportunity to decompress an unsafe situation. The protocol was instituted to guarantee a 1-hour breather for the overloaded hospital but to limit this to no more than 1 hour out of 8. The objective of this study was to ascertain the effect of that protocol on ambulance diversion hours and patient dropoff times. We hypothesized that this countywide EMS
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protocol which limited ED diversion would be associated with a significant decrease in ambulance diversion and a concomitant increase in EMS drop-off times in the ED.
2. Materials and methods Because of the problems associated with diversion, a new countywide EMS protocol limited the time that EDs were on diversion to 1 hour after which time they were forced open for the subsequent 8 hours. This protocol restricted total diversion time for any given ED to 3 h/d or approximately 90 h/mo. The decision to trigger ambulance diversion was determined by the attending physician and nursing supervisor based on the degree of overcrowding (ie, perception of inadequate resources to meet patient demand) with no established countywide standards. The implementation of the protocol began in March 2005. Emergency medical service units disregarded the ED status only for major trauma, which went to the trauma center. For the purpose of this study, EDs were categorized as either open (no ambulance diversions) or closed (ambulances diverted). With this type of protocol, we hoped the local system would deliver patients more equitably to their correct institution and the ambulances would be more available in the community for ongoing transports. This was a pre/postdesign study of a change in the local protocol for ambulance diversion. Our institutional review board approved the study. This study was conducted in a county with an area of approximately 1200 square miles and a population in excess of 625 000 people. The catchment area is geographically diverse, consisting of urban, suburban, and rural regions. Ten EDs including one level 1 trauma center serve this population. The EMS system in the study region has a 2-tiered structure in which fire fighters are first responders with basic and advanced life support skills and private contractors provide transportation to hospitals. Written protocols guide medical direction with supplemental directions provided by a hospital-based medical control physician, if necessary. EMS units transport patients to the closest hospital capable of appropriate treatment. Although major trauma is never diverted from the trauma center, diversion applies to all other ambulance patients. Patient requests are honored unless the requested receiving hospital is on diversion. Monthly data were collected from the local transport service continuous quality improvement reports consisting of the number of transports, the call acuity (eg, priority 1— emergent, priority 2—urgent), and the response, transport, and drop-off times. EMSystem (Milwaukee, Wis), an Internet-accessible network, provided real-time information regarding the operating status of EDs, intensive care units, and inpatient facilities of hospitals throughout the county. Comprehensive data for the operating status of all EDs in the county were collected from EMSystem during the pretrial (September 1,
672 2004, through February 28, 2005), interim (March 1, 2005, through August 31, 2005), and posttrial (September 1, 2005, through February 28, 2006) periods. The pre- and posttrial periods represented the same 6 months separated by 1 year. The interim period represented a retraining period that allowed hospitals to learn the new protocol for diversion. This study's primary outcome measure was the total monthly duration (in hours) of ambulance diversion during the pretrial, interim, and posttrial periods. Two secondary outcome measures were chosen because they are known correlates of EMS resource utilization. The first secondary outcome measure was the average drop-off time for 90% of patients (in minutes). Drop-off time represents the time it takes for EMS personnel to become available for service after arrival with a patient to an ED 90% of the time. The second secondary outcome measure was additional time over 15-minute allowance (in hours) during the study periods. As fifteen minutes is a standard allotted time for a drop-off in this system, any delay beyond this time represents a decrease in the number of available ambulances. Thus, additional unit hours per month = [(90% drop-off time − 15 minutes) × no. of transports]/60 minutes. Both of these were readily available from the participating EMSs.
2.1. Statistics Descriptive statistics were used for number of ambulance transports and for the primary outcome measures. Analysis of variance and a Tukey post hoc analysis were used to compare the difference in means between the pretrial, interim, and posttrial periods. A P value of less than .05 was considered significant.
3. Results There were a total of 73295 transports to the region's EDs during the study period. Table 1 (line 3) shows that the monthly average transports for the 3 periods were not significantly different. The adaptation of the diversion guidelines reduced mean monthly diversion hours from 305 to 54 hours (difference, 251 hours; 95% CI, 136-368) between the pretrial and posttrial periods (see Table 1). This corresponds to an 82% reduction in diversion hours during this period. Fig. 1 shows the number of ambulance diversion hours per month during the 3 study periods. During the interim period, a progressive reduction in the time EDs were closed to ambulance traffic is demonstrated. However, from the interim to posttrial period a dramatic decrease in ambulance diversion was noted consistent with EDs adhering to the new guidelines. Secondary outcomes are also illustrated in Table 1. The average percent time closed decreased from 4.7% to 0.8% (difference, 3.90%; 95% CI, 2.05-5.74) between the pretrial and posttrial study periods with a concomitant drop in
O.K. Asamoah et al. Table 1 Comparison of diversion measures during the consecutive thru 6-month periods of the study (pretrial, interim, and posttrial) Pretrial
Interim period
Posttrial
Systemwide Monthly duration 305 ± 102 275 ± 85 54 ± 15 ⁎ of ambulance diversion (h) Average % of 4.7 ± 1.7 4.2 ± 1.3 0.8 ± 0.2 ⁎ time closed Number of monthly 3960 ± 162 4167 ± 147 4089 ± 216 transports Average 90% drop- 21.1 ± 1.2 22.5 ± 0.5 ⁎ 22.8 ± 0.9 ⁎ off time (min) Additional unit 559 ± 96 722 ± 44 ⁎ 738 ± 56 ⁎ time (h) Major trauma center only 61 ± 10 53 ± 12 11 ± 4 ⁎ Monthly duration of ambulance diversion (h) 8.4 ± 1.4 7.3 ± 1.5 1.6 ± 0.5 ⁎ Average % of time trauma center closed Number of monthly 1095 ± 47 1184 ± 37 ⁎ 1165 ± 100 transports Average 90% drop- 30.27 ± 0.1 30.55 ± 0.2 ⁎ 30.54 ± 0.1 ⁎ off time (min) Additional unit 278 ± 13 307 ± 14 ⁎ 302 ± 25 ⁎ time (h) ⁎ P b .05.
time closed at the major trauma center. There was a significant increase in the average drop-off time (difference, +1.66 min/mo; 95% CI, 0.33-2.98), and additional unit time (difference, +178 h/mo; 95% CI, 74-283 hours) when comparing pretrial and posttrial periods. We were also determined that this novel diversion protocol had a similar effect on diversion statistics at the only level 1 trauma center in the system. As shown in Table 1 a substantial reduction in mean closed hours is observed in the posttrial period relative to the pretrial period (difference, −50 hours; 95% CI, 40-60). This represents an 82% reduction in closed hours at the level 1 trauma center or a significant decrease in percent closed time (difference, 6.8%; 95% CI, 5.5-8.2). A small but statistically significant increase in the 90% average drop-off time is noted at the trauma center between the pre- and posttrial periods (difference, 0.3 minutes; 95% CI, 0.1-0.5) with a parallel increase in additional unit hours (difference, 24 hours; 95% CI, 0.6-45.3).
3.1. Limitations and future directions This study has a number of limitations. It is a study over time and therefore can be biased by outside influences that
A novel diversion protocol dramatically reduces diversion hours
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This study only represents the results of 1 system and may not have external validity. Emergency medical systems that do not have the same operational characteristics as ours may respond quite differently to such a diversion protocol. This is just the beginning stages of an experiment in our community to decrease diversion and improve EMS drop times. In the future we will look at the longer term consequences and changes required to continue to manage the system in the best possible manner.
4. Discussion
Fig. 1 Graph of the changes that occurred over time in the pre-, interim, and post-trial periods. The dramatic decrease can be seen in the changes over time. The 3 trial periods, each 6 months in length, were the pretrial (September 1, 2004, through February 28, 2005), the interim (March 1, 2005, through August 31, 2005), and the posttrial (September 1, 2005, through February 28, 2006) periods. The pre- and posttrial periods represented the same 6 months separated by 1 year. The interim period represented a retraining period that allowed hospitals to learn the new diversion protocol.
occurred during the study period of which we were not aware. As ED overcrowding has become worse over time, we would have expected an increase in some of the variables collected, not a decrease. Thus, we believe that the changes noted in this study are a result of the protocol-based intervention within the EMS system. Statistically, the analysis of variance does not address the relationship between time points. If we had access to software that analyzed time series using an autoregressive integrated moving average model, it may have been a clearer reflection of the results. We are unable to specifically temporally quantify the system overcrowding; however, the trauma center ED census did not change during the study period suggesting no change in overcrowding. This does not take into account the possibility that the severity of illness of our patients was changing. Another limitation is that we did not look at patient data in terms of changes in morbidity and mortality. Patientcentered outcomes, although more difficult to obtain, would have strengthened the argument for or against this new policy. The only suggestion of improvement that we obtained was that patients were reaching their destination of choice and hospital with their medical records. We can speculate that this improved overall care. Another area in which improvement could be documented is on the financial impact to each hospital and to the system. These data were not available to the investigators but were the impetus for the changes reported. Hospitals felt that their patients being diverted to other hospitals was having a detrimental effect on their budget.
Emergency department personnel are acutely aware of crowding issues and ensuing ambulance diversion. Capacity problems are a routine part of clinical practice in many EDs that have recently garnered federal attention. In their series of reports [15-17] on the current state and future vision of emergency care, the IOM put forth several recommendations to mitigate ED crowding. However, until the ED community, hospital administrators, and policymakers are able to find effective solutions for the current crisis, ambulance diversion will continue to be a natural response to reduce patient influx and reestablish equilibrium between limited ED resources and apparently unlimited patient demand. We chose the solution of simply removing diversions from our system, except in rare circumstances. Decrease diversion has been shown to be of benefit to all hospitals systems [30]. The basis for overcrowding is complex and can be linked to a number of interwoven factors. These can include “boarding” admitted patients [8], nursing staff shortages, decreased access to primary care [7], and an absolute decrease in the total number of EDs in the face of increasing demand [31]. Irrespective of the underlying basis of ED crowding, the result is decreased patient throughput, fewer available ED beds, and stretchers lining hallways. Emergency department closure to incoming ambulance traffic is, theoretically, a tool that should be used on rare occasions when patient safety is truly compromised. This strategy temporarily alleviates “front end” pressure enabling limited ED resources to be focused on patients who are in the ED. Elimination of ambulance diversion can only effectively be realized through changes in hospital and ED processes. However, overuse of diversion can be mitigated by countywide protocols as successfully used in San Diego, California [32]. This study demonstrates a significant reduction of ambulance diversion in a heterogeneous county composed of urban, suburban, and rural regions. Our study confirms that a strict protocol regulating the duration of time an individual ED can be closed to ambulance traffic yields clear improvement in measurable outcomes. However, successful ambulance diversion is contingent upon collaboration of all EDs in the network and adherence by prehospital providers. This county was successful in decreasing ambulance
674 diversion by 82% during the posttrial period. This actually required less system effort than was described by Patel et al [18] in the Sacramento system. The primary difficulty we found in instituting this protocol was political. Hospitals were concerned about their inability to take care of the influx of patients that the protocol would cause. However, this was overridden by the significant belief that it was a disservice to the patients to be taking them to hospitals that did not know them or have their records, only to return them to their own hospital at a later time. The protocol was so successful that it is still in effect more than 1 year after the termination of the study. We believe that this dramatic reduction in diversion throughout the county allowed EMS personnel to more easily transport patients to the closest appropriate facility and maximized the opportunity for patient transport to a hospital of his/her choice. We believe that an effort to decrease diversion was of benefit to all of the hospitals in our system. Multiple communities have addressed the issue of ED crowding and have sought different methods to reduce ambulance diversion. For example, Lagoe et al [33] describe the implementation of an Internet-based EMS software system that provided real-time ED closure data and facilitated a cooperative effort to reduce community-wide ambulance diversion in Syracuse, New York. Although impressive reduction in diversion hours was found during the study period, this was accomplished through each individual hospital implementing its own measures to limit closures rather than establishing multi-hospital protocols. This study represents the third report of an attempt to decrease diversion through area-wide protocol. San Diego County also undertook measures to decrease ambulance diversion. Vilke et al [19] describe a community-wide intervention in which each hospital could only go on diversion for 1 hour, after which it had to receive at least 1 ambulance patient before returning to diversion status. In the San Diego protocol, they required hospitals to take their own patients even if on diversion. The authors report a dramatic 73% reduction in diversion hours during the trial period and a small subsequent increase of 17% diversion hours from the trial to posttrial period. Like the present study, there was minimal change in the number of runs/month during the study period. Although the authors admit that relaxed scrutiny of the diversion protocol may be a contributing factor, they did not anticipate a return to preintervention diversion hours. Another community-based approach to ambulance diversion was adapted in the Sacramento metropolitan area [18]. Sacramento implemented a policy that allowed each hospital to close for no more than 3 hours before opening and remaining open for at least 1 hour. This study also resulted in a 74% decrease in diversion hours from the preintervention to the postintervention period. Although this reduction in diversion hours was quite impressive, the ability for a facility to divert ambulances for 3 consecutive hours could adversely affect nearby EDs and the EMS system. The study covered a 3-year period during which the area population, the number
O.K. Asamoah et al. of ED visits, and the number of EMS runs all increased dramatically. Neither Sacramento nor San Diego looked at the adverse effect of ambulance diversion changes on drop times for the EMS. In theory, ambulance diversion is a tool used only when patient safety would be compromised by the addition of another ambulance patient. In this scenario, a sustained reduction in ambulance diversion could only be realized through changes in internal hospital processes that optimize patient disposition to an inpatient bed or discharge from the ED. Our data support this notion. The remarkable reduction of ambulance diversion hours in this study was accompanied by a 32% increase in additional monthly drop-off hours in the overall system. Transfer of patient care was likely prolonged owing to lack of available space to accommodate another stretcher. In fact, there is a nationwide trend of EMS crews detained at hospitals upwards of several hours [34,35]. Accordingly, paramedics are not available for the next potential critical call.
5. Conclusion A coordinated effort to minimize ambulance diversion was successful in a large community composed of urban, suburban, and rural populations. Although the dramatic reduction in diversion hours facilitates patient transport to the nearest ED or hospital of first choice, the increased EMS drop-off time may compromise the 911-response system. This is the first study to consider the impact of overcrowding on ambulance drop times. The decrease in diversions may negatively impact ambulance services which have to wait longer to drop-off patients at crowded facilities.
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