a b s t r a c t

Introduction: Influenza vaccination is a recommended tool in preventing influenza-related illnesses, medical visits, and hospitalizations. With many patients remaining unvaccinated each year, the Emergency Department (ED) represents a unique opportunity to provide vaccinations to patient not yet vaccinated. However, busy urban safety-net EDs maybe challenged to safely execute such a vaccination program. The aim of this quality im- provement project was to assess influenza vaccination feasibility in the ED and improve influenza vaccination rates in our community.

Methods: The quality improvement work-group, comprised of ED physicians, nurses, and pharmacists, designed and implemented an influenza vaccination protocol that aligned with the ED workflow. The outcome measure was the total number of patients vaccinated per month and per influenza season. process measures included the type of Influenza vaccine administered and type of care area within ED. Balancing measures were also in- cluded.

Results: Following the initiative, a total of 337 patients received influenza vaccinations in the ED between Sep- tember 1, 2018 and December 31, 2020 compared to none during the previous influenza season. With each in- fluenza season, the number of vaccinated patients increased from 61 to 134 and 142, respectively. The average age of the patients was 48.23 +- 15.29, 52.89 +- 15.91, and 44.92 +- 18.97 years old. Most patients received the vaccination while roomed in the high acuity section of the adult ED. No adverse effects or automated dispensing cabinet stockouts were observed.

Conclusion: Our structured program indicates that influenza vaccine administration to eligible patients is feasible in a busy urban safety-net ED. Piloting new and further developing existing ED-based influenza vaccination pro- grams have the potential to significantly benefit public health.

(C) 2021

1. Introduction

Influenza remains a ubiquitous disease throughout the United States with an estimated 48.8 million cases of influenza And 52,000 influenza- related deaths during 2017-2018. That influenza season accounted for over 1.9 million Emergency Department (ED) visits [1], and nearly

* Corresponding author at: Boston Medical Center, Department of Pharmacy, 850 Harrison Ave, Suite BN-C7, Boston, MA 02118, United States.

E-mail addresses: [email protected] (N.M. Farrell), [email protected] (M. Lamb), [email protected] (W.E. Baker), [email protected] (B.J. Gendron)

, [email protected] (D. Fett), [email protected] (N. Figueroa),

[email protected] (D. Margetak), [email protected] (E.M. Schechter-Perkins).

37% of all ED visits required hospitalization with the majority being el- derly [1,2]. Influenza may account for 18,000 to 97,000 intensive care unit admissions depending on the year [3,4]. Furthermore, recent influ- enza infections can contribute to increased ED volume and Prolonged hospitalizations by triggering acute myocardial infarctions and strokes, exacerbating chronic conditions, and causing bacterial co-infections [5-7]. ED length of stay, ED crowding, healthcare-associated influenza transmissions to ED patients and ED Healthcare workers, hospitaliza- tion, Ambulance diversion, and utilization of ED resources are also in- creased during Influenza seasons [8-12]. Influenza and influenza vaccination rates remain a problem for patients, EDs, and hospitals.

In 2017-2018, influenza vaccinations in the United States were esti- mated to have prevented over 7.1 million illnesses, 3.7 million medical visits, 109,000 hospitalizations, and 8000 deaths [13]. For every 29

https://doi.org/10.1016/j.ajem.2021.12.021

0735-6757/(C) 2021

and 42 vaccinations, one case of influenza-like illness was prevented in Healthy adults and the elderly, respectively. Every 71 and 30 vaccina- tions in healthy adults or elderly patients, respectively, prevented one case of influenza. One hospitalization was prevented through the vacci- nation of 1223 healthy adults and 4127 elderly patients [14-17]. De- pending on the season, 158 to 753 vaccinations in elderly patients could prevent one death [18]. Every 34 vaccinations in patients 80 years and older prevented one death from all-causes [19]. Despite documented efficacy in preventing or lessening the severity of influ- enza, only 37% of adults received the vaccine. Over the past decade, vac- cination rates for adults have never been greater than 55% [20]. Increasing current vaccination rates by as little as 5% can result in an 785,000 fewer illnesses and 11,000 less hospitalizations [21], which ex- trapolates to an estimated 29,500 fewer ED visits based on previous rates of ED visits requiring admission [1,2]. In a recent systematic re- view, barriers to receiving the vaccine included misconceptions about the disease or the vaccine, specifically low perceived risk of the disease and increased worry about the safety of the vaccine [22].

The ED represents a location in which a large proportion of patients may be unvaccinated without plans to receive one [23]. Several health care systems have implemented influenza vaccination programs in their respective EDs with success [23-27]. As a result of these successful implementation of ED influenza vaccination programs, the American College of Emergency Physicians (ACEP) endorses vaccinating adults against influenza in the ED. [28]

Historically, influenza vaccines were not offered in the ED at our in- stitution. Factors that contributed to this included not having influenza vaccination champions in the ED and not stocking the vaccines in the ED automated dispensing cabinets (ADCs). As a safety-net hospital, our pa- tient population was likely to experience disparities in seasonal influ- enza vaccination rates [29], which influenced our decision to offer influenza vaccines in the ED to improve vaccination rates in our com- munity. After the review of previous ED vaccination programs [23-27], our institution and department champions decided to implement an in- fluenza vaccination protocol with the aim to assess influenza vaccina- tion feasibility in the ED and improve influenza vaccination rates in our community.

1. Methods

This quality improvement (QI) project was conducted at an urban, academic, safety-net hospital with over 130,000 annual ED visits. The ED is comprised of low and high acuity care areas within an adult ED as well as a pediatric ED with 20,000 annual visits. In order to provide better care to our community, a QI work-group was created to develop and implement an influenza vaccination protocol in the ED beginning with the 2018-2019 influenza season. Influenza season was defined as September to May. QI initiatives were exempt from review from our hospital’s Institutional Review Board.

The QI work-group, comprised of ED physicians, nurses, and phar- macists, was created to design and implement an influenza vaccination protocol that would align with the ED workflow. The work group deter- mined that the influenza vaccines would be offered at the discretion of the provider to all eligible patients that were being discharged, in accor- dance with national Guideline recommendations [30]. Patients with a history of severe Allergic reactions to the influenza vaccine or Guillain- Barre Syndrome (GBS) within 6 weeks of previous vaccine administra- tion were not eligible to receive the influenza vaccine. Providers placed influenza vaccine orders in the Electronic Medical Record (EMR), which automatically selected the influenza standard dose or high dose based on the patient’s age. Prior to order verification, ED pharmacists con- firmed each patient’s ED influenza vaccination eligibility through the hospital’s EMR system and statewide registry [31]. Nurses would then perform barcode scanning prior to vaccine administration.

This protocol was evaluated using the Model for Improvement framework from the Institute of Healthcare Improvement [32]. Multiple

Plan-Do-Study-Act (PDSA) cycles that built on one another were con- ducted between September 2018 and December 2020. During PDSA cycle 1, the work-group first designed an influenza vaccination protocol (Fig. 1). Influenza vaccines were added to the ADCs in the ED. The vac- cination campaign was first rolled out to the low acuity care areas within the adult ED in October 2018 in order to reach patients not plan- ning on obtaining the vaccine from their primary care provider. The pro- vider and nurse staff for the low acuity, adult ED care areas was smaller compared to the entire department, which allowed for focused educa- tion and feedback prior to rolling out to the entire ED. As part of PDSA cycle 2, all care areas within the adult and pediatric ED could order influ- enza vaccines for their patients by December 2018. Signs instructing pa- tients to inquire about the influenza vaccine were also placed in patient rooms throughout the ED. From January to May 2019, pharmacy stu- dents assisted with Screening patients for eligibility during their week- day rotation hours as part of PDSA cycle 3. During the subsequent influenza seasons, ED staff received education at the beginning of the in- fluenza season (PDSA cycle 4) and the influenza vaccines could be or- dered for patients in September, which was when the hospital received its supply of vaccines. During the influenza season of 2020-2021, ED Research Assistants screened patients for eligibility and notified ED providers of patients interested in receiving the vaccine as part of PDSA cycle 5. Throughout, the work-group met regularly to discuss and evaluate the PDSA cycle changes.

The aim of this QI initiative was to assess influenza vaccination fea- sibility in the ED and improve influenza vaccination rates in our com- munity. The outcome measures included the total number of patients vaccinated per month and per influenza season. Process measures in- cluded the type of influenza vaccine administered as well as the type of care area within ED. Balancing measures included the number of ADC stock outs with active orders, vaccine administration to patients up-to-date with their seasonal influenza vaccine, and the number of se- vere adverse events. Severe adverse events included severe allergic re- actions, defined as difficulty breathing, hoarseness or wheezing, swelling around the eyes or lips, or hives, and the development of GBS within six weeks of vaccine administration. Run charts were created and analyzed utilizing QIMacros(R).

Fig. 1. Annual influenza vaccination screening pathway example.

Table 1

Influenza vaccination characteristics.

2017-2018 2018-2019 2019-2020 2020-2021

patients were vaccinated. An increase in vaccinations in the pediatric ED was observed (n = 21, 14.79%). Influenza vaccinations were ob- served to decrease during the later portions of the influenza seasons.

Age, mean +- SD N/A 48.34

+- 15.29

52.89

+- 15.91

44.92

+- 18.97

No adverse events or ADC vaccine inventory stock outs with active or- ders were observed. No patients that had already received their sea-

Influenza Vaccinations, n

Influenza Vaccine, n (%) Standard Dose	N/A	52 (85.25%)	99 (73.88%)	121 (85.21%)	4. Discussion
High Dose	N/A	9 (14.75%)	35 (26.12%)	21 (14.79%)	Since implementing an ED influenza vaccination protocol in October

0 61 134 142

sonal influenza vaccine were subsequently vaccinated in the ED.

Care Location, n (%) High Acuity Adult	N/A N/A	36 (59.02%)	106 (79.11%)	100 (70.42%)
ED Low Acuity Adult ED	N/A	24 (39.34%)	26 (19.4%)	18 (12.68%)
Pediatric ED	N/A	1 (1.64%)	2 (1.49%)	24 (16.90%)

1. Results

A total of 337 patients received influenza vaccinations in the ED be- tween September 1, 2017 and December 31, 2020 (Table 1). No patient received an influenza vaccine during the 2017-2018 influenza season and influenza vaccinations increased with each subsequent influenza season, following implementation during the 2018-2019 influenza sea- son (Fig. 2). On the influenza vaccination administration run chart, two significant shifts were observed during the 2018-2019 and 2019-2020/ 2020-2021 influenza seasons due to the presence of 6 consecutive points above the median line. During the 2018-2019 influenza season, a total of 61 patients were vaccinated in the ED. The majority of the pa- tients received the standard dose influenza vaccine (n = 52, 85.25%) and the remainder (n = 9, 14.75%) received the high dose influenza vaccine. Most patients were vaccinated in the high acuity (n = 36, 59.02%) and low acuity (n = 24, 39.34%) care areas of the adult ED. A total of 134 patients were vaccinated during the 2019-2020 influenza season. An increase in patients receiving the high dose influenza vaccine (n = 35, 26.12%) was observed and the majority of the administrations were in the high acuity care areas of the adult ED (n = 106, 79.1%). Dur- ing the first half of the 2020-2021 influenza season, a total of 142

2018, the annual number of patients vaccinated against influenza in the ED has grown steadily. The highest number of patients were vaccinated during the 2020-2021 influenza season, and that final number of vacci- nations is expected to exceed 142 given that 5 more months remain in this current influenza season. According to the numbers needed to vac- cinate [14-17], we prevented one case of influenza in elderly patients during 2019-2020, 4 and 2 cases of influenza and influenza-like illness in pediatric patients during 2020-2021, and one case of influenza in adults during both 2019-2020 and 2020-2021. Preventing a case of in- fluenza in an elderly patient also likely prevented an ED visit and result- ing hospitalization [1,2]. In subsequent years, increasing our vaccination efforts 10 fold in elderly patients could help prevent approximately 30 ED visits and hospitalizations [14,15]. The vaccination campaign in the ED allowed us to reach our Vulnerable patient population that is served by our safety-net hospital. Other studies have also demonstrated that offering influenza vaccines in the ED allowed for opportunities to vacci- nate patients that didn’t otherwise have plans for vaccination due to barriers that included lack of insurance and primary care provider [23,25]. Other EDs can expect to have similar when results imple- menting influenza vaccination programs.

Like other studies [23-27,33-37], we demonstrated that influenza vaccination campaigns are feasible in the ED. What sets our ED influenza vaccination campaign apart is that it was conducted at one of the busiest EDs in the United States. Overall, the literature suggests that between 34% and 67% of eligible patients were willing to receive their influenza vaccination in the ED. [23-27,33,34,37] Common patient-specific bar- riers to vaccination noted include concerns about vaccine effectiveness,

Fig. 2. Emergency department influenza vaccination run chart.

side effects, and perception of low risk for influenza [23-25]. Healthcare provider survey results also demonstrate support for vaccinating pa- tients against influenza in the ED when there is sufficient time, staffing, and resources available [33,36]. Only 69% of ED physicians and nurses report intention to receive annual influenza vaccinations [38], which may also influence their support of influenza vaccination programs in the ED and provision of education to patients on the importance of vac- cination. Additional barriers encountered by other public health initia- tives in the ED include cost, space, privacy, education and training, and patient follow-up [39-42].

A variety of different approaches have been taken by EDs, including a pharmacist-, nurse-, and physician-driven protocols with or without the addition of Clinical decision support [23-27,33,34]. While clinical deci- sion support had the most vaccinations [34], it was not implemented as part of this QI initiative due to the length of time needed for the infor- mational technology infrastructure build for the ED setting, and staff concerns for alert fatigue. Additionally, nurse-driven protocols are often preferred by ED staff and are the standard for influenza vaccina- tions in hospitalized patients [35,36]. A nurse-driven influenza vaccina- tion protocol was not implemented as part of our project due to not having the informational technology infrastructure in place in the ED to support that workflow; however, there are plans to build that infra- structure in the future.

The development and implementation of influenza vaccination pro- grams in EDs across the United States will take time before a large public health benefit can be observed. If all EDs implement influenza vaccina- tion pilot programs and then further development those programs, the cumulative number of vaccinations per season could increase total vac- cinations by 5%, which would prevent an additional 785,000 influenza illnesses, 381,000 medial visits, and 11,000 hospitalizations [21]. Com- bining the current vaccination rate with the 5% increase in vaccinations would help prevent an estimated total of 5.2 million illnesses, 2.7 med- ical visits, and 69,000 hospitalizations [15,21]. Widespread adaption of influenza vaccination programs in the ED could help to almost eradicate influenza similar to the common practice of ED tetanus vaccinations aiding in the reduction of annual tetanus cases and deaths by 92.9% and 99.2%, respectively [43,44]. Provision of influenza vaccinations in the ED can also result in decreased utilization of ED resources, ED length of stay, ambulance diversion, hospitalizations, and healthcare- associated influenza transmission to patients and healthcare workers later in the influenza season [8-12]. The concurrent coronavirus disease 2019 (COVID-19) pandemic further consumes these same resources and increases workload [45].

The influenza vaccinations in the ED had greater public health ram- ifications during the current and previous influenza seasons due to con- current coronavirus disease 2019 (COVID-19) pandemic. Evidence suggests that influenza co-infection with COVID-19 may lead to worse outcomes, which further emphasizes the need for influenza vaccina- tions [46]. Secondly, the overlap of symptoms between COVID and influ- enza means that decreasing cases of influenza also decreases the number of workups for COVID-19 that are required for patients with upper respiratory symptoms. Finally, the influenza vaccinations in the ED help with departmental readiness for mass vaccination campaigns for pandemic response. Surveys on pandemic influenza ED prepared- ness have demonstrated that only 60% of EDs have plan for pandemic influenza response including vaccine distribution [47,48]. During the 2020-2021 influenza season, our influenza vaccination workflow also serves as a practice run for staff for when the ED may administer COVID-19 vaccines in response to the current COVID-19 pandemic.

There are several limitations to this project. The total influenza vac- cination numbers were too small to quantify its impact on ED visits and hospitalizations related to influenza. Influenza vaccinations were at the discretion of the provider. Vaccinations were not offered to all patients presenting to the ED, and we did not capture and analyze factors that could have influenced provider’s offering vaccination or patient’s consenting. Pharmacy student and research assistant patient eligibility

screening was limited, which placed greater reliance on providers to inquire about the patient’s influenza vaccination status. Additionally, we were unable to trial a nurse-driven influenza vaccination protocol.

5. Conclusion

Our structured program indications that influenza vaccine adminis- tration is feasible in high volume EDs. Piloting new and further develop- ing existing ED-based influenza vaccination programs have the potential to significantly benefit public health.

Prior presentations

None.

Financial support

None.

Declaration of Competing Interest

Dr. Elissa M. Schechter-Perkins receives research funding from Gil- ead FOCUS, Inc. Dr. William E. Baker previously received consulting pay- ments from CRICO AMC PSO and Well Sense Health Plan. Dr. Natalija Farrell is supported by a grant from the Massachusetts Department of Public Health Bureau of Substance Addiction services to Develop Opioid urgent care centers (RFR #163274).

Acknowledgements

None.

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