Impact of Hospital-Employed Physician Assistants on a Level II Community-Based Orthopaedic Trauma System : Journal of Orthopaedic Trauma

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Impact of Hospital-Employed Physician Assistants on a Level II Community-Based Orthopaedic Trauma System

Althausen, Peter L. MD, MBA*; Shannon, Steven BS; Owens, Brianne MD; Coll, Daniel PA-C; Cvitash, Michael PA-C; Lu, Minggen PhD§; O’Mara, Timothy J. MD*; Bray, Timothy J. MD*

Author Information
Journal of Orthopaedic Trauma 30():p S40-S44, December 2016. | DOI: 10.1097/01.bot.0000510721.23126.48
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Abstract

Objectives: 

The American Academy of Orthopedic Surgeons and the Orthopedic Trauma Association have released guidelines for the provision of orthopedic trauma services such as adequate stipends, designated operating rooms, ancillary staff, and guaranteed reimbursement for indigent care. One recommendation included a provision for hospital-based physician assistants (PAs). Given current reimbursement arrangements, PA collections for billable services may not meet their salary and benefit expenses. However, their actions may indirectly affect emergency room, operating room, and hospital reimbursement and patient care itself. The purpose of our study is to define the true impact of hospitalbased PAs on orthopaedic trauma care at a level II community hospital.

Design: 

Retrospective case series.

Setting: 

Level II trauma center.

Patients/Participants: 

One thousand one hundred four trauma patients with orthopaedic injuries.

Intervention: 

PA involvement.

Main Outcome Measurements: 

Emergency room data such as triage time, time until seen by the orthopedic service, and total emergency room time was recorded. Operating room data such as time to surgery, set-up time, total operating time, and out of room time was entered as well. Charts were reviewed to determine if patients were given postoperative antibiotics and Deep Venous Thrombosis (DVT) prophylaxis. Intraoperative and postoperative complications were noted, and lengths of stay were calculated for all patients.

Results: 

At our institution, PA collections from patient care cover only 50% of their costs for salary and benefits. However, with PA involvement, trauma patients with orthopedic injuries were seen 205 minutes faster (P = 0.006), total Emergency Room (ER) time decreased 175 minutes (P = 0.0001), and time to surgery improved 360 minutes (P . 0.03). Operating room parameters were minimally improved, but postoperative DVT prophylaxis increased by a mean of 6.73% (P = 0.0084), postoperative antibiotic administration increased by 2.88% (P = 0.0302), and there was a 4.67% decrease in postoperative complications (P = 0.0034). Average length of stay decreased by 0.61 days (P = 0.27).

Conclusions: 

Although the PA’s collections do not cover their costs, the indirect economic and patient care impacts are clear. By increasing emergency room pull through and decreasing times to Operating Room (OR), operative times, lengths of stay, and complications, their existence is clearly beneficial to hospitals, physicians, and patients as well.

Level of Evidence: 

Economic Level IV. See Instructions for Authors for a complete description of levels of evidence.

INTRODUCTION

The American Academy of Orthopedic Surgeons and the Orthopedic Trauma Association have released guidelines for the provision of orthopedic trauma services such as adequate stipends, designated operating rooms, ancillary staff, and guaranteed reimbursement for indigent care. One recommendation included a provision for hospital-based physician assistants (PAs). Interestingly, no published literature exists to date on the impact of PAs on an orthopedic trauma service. The use of PAs in trauma care has increased at both academic and nonacademic centers due to loss of residency programs, work hour regulations, and increased patient loads as emergency rooms have closed.1,2 Our institution has a well-developed trauma system which has been the subject of several publications which have demonstrated the clinical and economic viability of communitybased level II trauma systems3–8. Current contracting arrangements have provisions for hospital-based trauma PAs which are not contingent on their ability to generate revenue. Given current reimbursement arrangements, it is possible that PAs may not directly cover their costs. In addition, hospital-based accounting often designates PA programs as “losses” to the hospital when viewed as individual profit centers. However, their actions may indirectly affect emergency room, operating room, and hospital reimbursement and the quality of patient care itself. Physician assistant presence may also affect physician quality of life, improve communication with hospital staff, and assist in cost containment programs. The purpose of our study is to define the clinical and financial impact of hospitalbased PAs on orthopaedic trauma care at a level II community hospital.

MATERIALS AND METHODS

After institutional review board approval, a retrospective chart review was performed on trauma patients with orthopedic injuries at our facility from January 1, 2007, to December 31, 2007. During this time frame, 2 hospital-employed PAs were utilized to cover all orthopedic trauma needs from 8 AM to 8 PM. Each PA performed 12-hour shifts for 3 consecutive days. Only1 PA was present during these shifts with coverage consisting of Monday through Saturday. The 18 Orthopedic surgeons supervising PAs and covering trauma call are all private practice physicians and members of a community-based trauma panel, which have been described in previous publications3,4 . Both PAs and surgeons on call carry trauma pagers and report to emergency room as soon as possible. Response depends on surgeon needs. When PAs are not available, the attending surgeon is always the primary orthopedic responder for Emergency Room (ER) consults.

Presence or absence of PA involvement in patient care was recorded, and the resulting groups were compared. Emergency room data such as triage time, time until seen by the orthopedic service, and total emergency room time was recorded. Operating room data such as time to surgery, setup time, total operating time, and out of room time was entered as well. Charts were reviewed to determine if patients were given pre/postoperative antibiotics and Deep Venous Thrombosis (DVT) prophylaxis in accordance with Surgical Care Improvement Project protocols. Intraoperative and postoperative complications such as death, loss of reduction, hardware failure, postoperative infection, deep venous thrombosis, and pulmonary embolus were noted and lengths of stay were calculated for all patients. ER and Operating Room (OR) cost per minute data were calculated as the departmental direct variable cost as reported by the hospital finance department.

Data was analyzed with SAS version 9.2 for Microsoft Windows. Percentages, means, and standard deviations were used to describe the variables. The x2 tests were used to ascertain the associations with regard to gender, OR complications, PA present, DVT prophylaxis, Post-Operative (post Op) antibiotics, and post Op complications. Two-sample t tests were performed to compare means of age, setup time, OR time, Time out, Length of Stay (LOS), triage time to out of ER, triage time to time seen by the orthopaedic trauma service, and triage time to time of surgery. Two-sample t tests were employed for comparison of means of setup time, OR time, time out, triage to out of ER time, triage to time seen by orthopaedic trauma service, triage to time of surgery, and length of stay between PA present/absent. Level of significance was set at P ˂ 0.05.

RESULTS

Systematic chart review of 64,823 emergency room visits identified 1104 trauma patients with orthopaedic injuries in the year 2007. Physician assistants were present in the care of 310 patients and absent in the care of 687 patients. The patient demographic data is presented in Table 1. Groups were comparable across all variables. Physician assistant presence resulted in a 205 minutes faster orthopaedic service response time (P =0.0006), a 175.7 minutes decrease in total ER time (P = 0.0001) and a 360 minutes improvement in time to surgery (P = 0.03) (Table 2). The use of PAs in expediting emergency room patient care and decreasing transfer time to the operating room was clearly beneficial.

T1
TABLE 1.:
Patient Demographics
T2
TABLE 2.:
ER Parameters

Operating room parameters were minimally improved with PA presence (Table 3). Setup time decreased only 0.43 minutes (P = 0.03). Average OR time, time from wound closure to wheels out, and complication rates all remained unchanged.

T3
TABLE 3.:
OR Parameters

Hospital parameters were also positively affected by the presence of PAs. (Table 4). There was a statistically significant improvement of the quality of patient care in patients seen by PAs. The use of DVT prophylaxis increased by a mean of 6.73%(P = 0.0084), postoperative antibiotic administration increased by 2.88% (P = 0.0302), and there was a 4.67% decrease in postoperative complications (P = 0.0034).

T4
TABLE 4.:
Hospital Parameters

During the period of study, PA charges amounted to $703,896 and collections totaled $125,246, resulting in a collection rate of 17.8%. Eighty-nine percent of charges resulted from surgical assisting, whereas 10.4% arose from ER evaluation and management and 0.6% from inpatient Evaluation and Management interactions. Our payer mix is presented in Table 5. At our institution, the PA’s collections in 2007 from patient care covered only 50% of costs including salary and benefits. However, collections are not their only financial contribution. The average cost per minute for emergency room time at our facility was found to be $0.76 per minute, not including ancillary costs. When considering that our PAs decreased ER time by a mean of 175.7 minutes, we were able to calculate that per orthopaedic trauma patient seen, the PAs saved the hospital $133.53 per Authors for a complete description of levels of evidence. patient. In 2007, 310 patients were documented as being managed in the ER by a PA. This resulted in $41,394 in savings. The 687 patients not seen by PAs presented a lost opportunity of $91,735 in savings. If each patient had been managed by a PA in 2007 (n = 1104), the result would have been a possible $147,417 in savings. The average cost per minute for the operating room at our facility was found to be $24.06, not including overhead costs. We found that only the decreased setup time was statistically significant with the presence of PAs at a mean decrease in 0.43 minutes, which resulted in savings of $3,207 in 2007 based on OR costs. If a PA had assisted in setup for each of the orthopaedic trauma cases in 2007 (n = 1104), the savings would have been a possible $11,421.

T5
TABLE 5.:
Payer Mix

DISCUSSION

The use of physician extenders such as PAs and nurse practitioners has become increasingly common at both academic and nonacademic medical centers.1,2 This has occurred due to loss of residents, 80-hour work-week restrictions, and increasing financial pressures. In 2009, the annual census data from the American Academy of Physician Assistants reported an increase in the number of Physician assistants working in trauma centers.1 In 2010, approximately 1/3 of all major trauma centers reported utilizing physician extenders.1 Nineteen percent of those who did not currently utilize mid-level providers stated that they intended to do so in the future. Most of these institutions currently utilize these individuals for trauma resuscitation, performing history and physicals in the emergency room, assisting with surgery, and dictating discharge summaries.

Prior studies have demonstrated increased efficiency of health care delivery due to the addition of PAs to a general surgery trauma service.2,9 Miller et al2 reported a 33% decreased length of stay, along with a 43% decrease in transfer times to the OR; 51% decrease in time to intensive care unit (ICU); and 20% decrease in transfer time to floor with the incorporation of Physician Assistants. Christmas et al9 also demonstrated that “physician extenders” decreased floor, ICU, and hospital length of stay. At our institution, the PA’s collections from patient care cover only 50% of their costs; but with this overall increase in efficiency demonstrated by prior studies and ours, it is clear that PAs save the hospital costs indirectly by increasing overall efficiency.

PA Responsibilities

The ability of physician extenders to assist in patient care and improve efficiency in part is based on their scope of practice. PA responsibilities are often governed by state laws or hospital regulations. An understanding of privileging is vital to utilization of services. Our PAs were able to respond to trauma activations, assist in OR, attend multidisciplinary rounds, interface with discharge planning, perform rounds, and dictate discharge summaries. At our institution, they are not able to dictate admission History and Physicals or write admission orders due to hospital by-laws. They are not able to perform invasive procedures on their own such as traction pin placement or lines. They can reduce fractures and dislocations, suture wounds, and place wound vaccuums. At other institutions, responsibilities are often similar to the duties of some surgical residents. General surgeons have utilized PAs to insert chest tubes, place central lines, perform diagnostic peritoneal lavage, and insert percutaneous tracheostomies.2,9,10 Neurosurgeons have utilized PAs for intracranial pressure monitors11 Although helpful procedural assistance does not seem to be as important care coordination and clinic assistance.12 Trauma multidisciplinary rounds are key to coordinating care, avoiding patients being fed before OR, communicating weightbearing restrictions, antibiotic recommendations, and discharge planning needs. As our study demonstrates, each parameter of care can be affected by PA usage.

Emergency Room Care

Our study clearly demonstrates the benefit of PAs in expediting emergency room management of orthopaedic trauma patients. Physician assistant presence improved ER response time by 205 minutes and decreased total ER time by 176 minutes. This improved efficiency resulted in significant cost savings and in improving ER flow and allowing more availability for new patients. In a comparison study by Oswanski et al13 at an academic institution, authors reported that PAs responded to 100% of trauma activations, whereas residents had a 51% participation rate. It is not surprising that this resulted in a statistically significant improvement in transfer time from the ER to the floor. Physician assistant involvement in the emergency room also decreased triage time to time of surgery due to care coordination for operative medical clearance, proactive scheduling, and earlier ER intervention. Such improvement is supported by Miller et al2 who noted a 51% decrease in transfer times to OR with PA utilization. At our institution, PAs are not available on Sundays and from 8 PM to 8 AM. We acknowledge that triage times may depend on day of the week and time of day and multiple other factors. Our study cannot address this variation but certainly demonstrates the effect of PA involvement.

Operating Room Care

In a community-based trauma system, much of the operating room setup is done by the physician, and many operations are done without an assistant. We hypothesized that PA presence would have a significant effect on OR parameters. However, this was not the case. Setup time was only marginally improved by 0.43 minutes, whereas operative time, time out of OR, and operative complication rates remained unchanged. However, what was not calculated was the timesavings for the orthopedic surgeons involved. Having a PA to set up the room, position the patient, and close the wound frees up the surgeon for other important clinical duties. Such timesavings has been reported by other authors. Upon implementation of Trauma Physician assistants at Hurley Medical Center, surgeons reported a timesavings of 4 to 5 hours per day.2 This accounted for more than 20% timesavings, allowing physicians to perform other duties.

Length of Stay

Multiple studies have demonstrated that the use of PAs significantly decreases hospital length of stay, resulting in hospital savings.9,12,14,15 In orthopedics, length of stay is often delayed by durable medical equipment delivery such as crutches or walkers. Adequate anticoagulation, indigent anticoagulation prescriptions, and home oxygen needs can be anticipated. Physician extenders are able to improve patient flow by coordinating care with discharge planners and social services. Flow is also improved because PAs are available to answer questions from other physicians, family members, and nurses regarding patients while physicians are performing other duties such as surgery or clinic.

Jarrett and Emmett14 demonstrated that adding NPs to a trauma service resulted in decreased length of stay for all injury severity scores. This hiring was initiated during the creation of a trauma disease management program to address 2 major barriers to care. They determined that patients were being “lost in the system” and that patients and families were not being adequately prepared for discharge. This co-ordination of care proved successful. Christmas et al9 reported decreases in ICU, floor, and overall lengths of stay using physician extenders on a general surgery trauma service. Spisso et al12 found a decreased length of stay for seriously injured patients from 8.10 to 7.5 days, whereas Fanta et al16 showed decrease from 4.51 days to 2.65 days over a 1-year period despite higher injury severity scores. Miller et al2 showed that the addition of PAs to a general surgery trauma service resulted in a 13% decrease in overall length of stay and 33% decrease in ICU stay for neurotrauma patients. Haan et al15 showed that addition of NPs to discharge rounds led not only to decreased LOS but also to increased admissions and patient volume. Our study demonstrated a 0.61-day decrease in length of stay, which was not statistically significant. However, improving LOS by half a day can result in significant cost savings.

Cost Savings

Our study demonstrates significant cost savings with significant decreases in ER time, OR setup time, and slightly improved LOS. Such results have been noted by other authors,9,17,18 but due to hospital accounting methods, exact costs are difficult to determine. Christmas et al9 demonstrated in a prospective study that the addition of physician extenders showed no change in direct cost to patient. However, their study provided no descriptors on what their costs were or how they were obtained. Derengowski et al18 showed that the use of NPs in a critical care setting resulted in a decrease in the number of daily diagnostic tests ordered. Certainly this would decrease overall costs to the patient. Finally, Schweer et al17 performed a financial analysis on the impact of pediatric trauma NPs during the first year of service and estimated $1,900,000 cost savings due to decreased LOS without an increased complication rate.

The factors of decreased setup time and decreased ER time had tangible cost savings, whereas we did not have a way of calculating savings for the time it took for patients to reach the OR from the time of triage. This variable is extremely important nonetheless because opportunity cost can be taken into consideration. This opportunity cost savings would be directly due to the fact that the faster patients reach the OR from the time of triage can ultimately result in an increase in number of OR cases a day due directly to an increase in number of trauma cases reaching the OR or by freeing up OR time for elective cases such as spine surgery. This opportunity cost can result in significant cost savings and increased hospital revenue. Given the multiple factors involved, the exact dollar amount of opportunity cost is unable to be determined.

It is apparent that every hospital system has a different dollar figure placed on their OR time or ER time, and the cost savings stated prior would not be directly transferable across systems. But with this information, health care systems could possibly determine the number of PAs they require on the orthopaedic trauma service to cover their salary, meet national recommendations, and also cut costs by factoring in the hospital systems own costs for ER time and OR time. In an era of cost cutting and improving patient care, each hospital system must take their situation into consideration to provide superior orthopaedic trauma care in a cost effective manner.

Time Savings

The time savings PAs can provide for physicians has been well documented. In a community-based system without resident assistance, this is even more apparent. Upon implementation of Trauma Physician assistants at Hurley Medical Center, surgeons reported a time savings of 4–5 hours per day.2 This accounted for more than 20% timesavings, allowing physicians to perform other duties. Spisso et al12 demonstrated decreased physician workload with the addition of PAs on a trauma service. With the use of NPs they showed decreased outpatient clinic waiting times from 41 to 19 minutes and fewer patient complaints. Timesavings for house staff averaged 352 minutes per day. In our system, PAs have enabled orthopedic trauma physicians to improve time management and the overall quality of care. This has also allowed trauma physicians to spend more time with family, more time for research and teaching, and will hopefully lead to increased longevity in trauma practices.

Quality of Care

Concern is always raised by physicians that employment of Pas/NPs may reduce the quality of care. This has not been borne out by previous studies. The Department of Surgery in Louisville analyzed patient outcomes after hiring of 2 NPs. Over a 3-year period, they found no adverse effects on patient mortality or quality of care.9 Dubaybo et al19 transitioned to utilizing PAs as primary care providers in a medical ICU. They found no changes in occupancy, mortality rate, or complications over a 2-year period. Similar results were published by Oswanski et al13 in 2004 when their hospital transitioned from surgical residents to PAs at a level II trauma center. They found no adverse effect on patient outcomes.13 Miller et al2 showed that trauma PAs performing invasive procedures had no complications in 70 diagnostic peritoneal lavages, 250 thoracostomies, and 80 arterial lines. They demonstrated a 2.9% complication rate regarding 270 subclavian catherizations. In the pediatric critical care setting, physican extenders have been utilized extensively.20 They are perceived to perform at the level of a second year resident and supported by physicians. Carzoli et al10 demonstrated no significant differences in management or outcome measures in a comparison of pediatric ICU patients treated by a team staffed by residents and 1 by neonatal nurse practioners and PAs.

Our study reveals that the use of PAs actually improves care, demonstrating statistically significant improvement of the quality of patient care: the use of DVT prophylaxis increased by a mean of 6.73%, postoperative antibiotic administration increased by 2.88%, and there was a 4.67% decrease in postoperative complications. These results as well would indirectly decrease the cost of patient care at our facility by decreasing the overall ramifications due to decreased DVT prophylaxis, postoperative antibiotics, and increased postoperative complications. Previous studies have demonstrated similar effects as well. Dhuper and Choksi21 analyzed outcomes when an academic internal medicine residency was replaced with a PA-hospitalist model. They found a lower mortality rate and lower readmission rate after the transition. Haan et al15 also found a statistically significant decrease in the readmission rate when NPs were involved in patient care. At one trauma center, mid-level providers were utilized to conducted tertiary surveys and co-ordinate follow-ups for incidental findings.22 They found that 7.4% of 1027 had incidental findings needing follow-up care such as pulmonary nodules or neoplasms, adrenal masses, or other neoplastic conditions. This certainly can help physician workload and decrease legal risks associated with trauma care.

Surgeons schedules are extremely busy and PAs may be able to provide more consistent personal floor care. Several studies have shown improved patient and family satisfaction scores with physician extender involvement. Fanta et al16 performed a prospective randomized study published improved patient and family satisfaction scores when treated by pediatric NPs compared to residents. This was supported by a study by Shebesta23 showing similar results. Nyberg et al24 found that patients treated by PAs/NPs were very satisfied with their care and that 85% of physicians and hospital employees felt that these employees made a positive impact on patient care.

CONCLUSIONS

The use of PAs on an orthopaedic trauma service in a community-based level II trauma system is clearly beneficial. Although the PA’s collections do not directly cover their salary, the indirect economic, and patient care impacts are clear. By increasing emergency room efficiency, decreasing times to OR, lengths of stay, whereas improving overall patient care, their existence is clearly beneficial to hospitals, physicians and patients as well.

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Keywords:

physician assistant; trauma system; economics

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