Adult Inpatient Services in Pediatric Hospitals: A National Mixed Methods Study

This explanatory mixed methods study took place from August 2020 to March 2021. It included a survey followed by semistructured interviews to develop a comprehensive understanding of active adult inpatient services in pediatric institutions in the United States. An active service was defined as one with institutional approval (eg, with staffing and business model) and expected patient consults over the study period.

The study population of interest was medical directors (or designates) of active adult inpatient services in pediatric institutions in the United States, which included both free-standing children’s hospitals and pediatric hospitals or units integrated in an adult hospital. Given an uncertain denominator (total number of services) in existence, we used a combination of purposive and snowball sampling to minimize risk of missing any existing services.¹⁰  We expected Med-Peds hospitalists would be engaged in or at least aware of these services given their presence in a pediatric setting. Thus, the survey was distributed through both author (R.P. and A.J.) personal connections as well as to the American Association of Pediatrics Section of Hospital Medicine and Med-Peds subsection listservs, the Med-Peds Program Director Association listserv, and the Society of Hospital Medicine’s pediatrics and Med-Peds special interest groups via the online collaboration platform HMx. Participants were asked to include names or programs that had similar adult inpatient services for our study team to approach. Survey and interview completion was voluntary.

We developed a web-based survey with 20 close-ended-questions to identify institutional demographics, service line characteristics, and patient populations seen (Appendix 1A). We tested the survey instrument internally to ensure feasibility and clarity. The interview followed a semistructured interview guide (Appendix 1B) and included questions regarding facilitators and barriers to creation of the adult inpatient service line, perceived benefits of the service, and any needed survey response clarifications. We refined the interview guide iteratively as interviews were conducted to enable clarity and explore new ideas.

Study data were collected and managed using REDCap electronic data capture tools hosted at our university.¹¹  Only completed survey entries were included in analysis. Interviews were conducted by phone in English by a trained study team member. Interviews were audio recorded and transcribed verbatim. Transcripts were then deidentified and uploaded to Dedoose Version 9.0.17.

Descriptive statistics were used for survey responses. Qualitative interviews were coded iteratively by 3 study team members using in-depth coding and thematic analysis.^12,13  Consistent with our exploratory mixed methods approach,¹⁴  we interpreted the findings from the survey and interviews in light of each other. A preliminary codebook was developed using the first 3 interviews in combination with survey findings. The coded interviews were then compared for agreement and finalized through consensus with iterative refinement of the codebook. All interviews were double-coded. Related codes were subsequently organized to identify emergent themes.

Ten institutions participated in the survey and subsequent interview. Nine (90%) identified having an active adult inpatient service (Table 1). One institution (10%) only had financial approval with expected consults to start within the year. Because of lack of billed consults and a final care model, survey data from this institution was excluded from analysis.

Eight out of 9 institutions identified their children’s hospital as free-standing with the nearest adult facility ranging from adjacent (<0.1 miles) to 5 miles away (Table 1). There was a wide range of time (0 to 17 years) that each service had existed. One institution also indicated having a designated adult hospital medicine service for adults with childhood-onset conditions at a neighboring adult hospital. Average patient census ranged from 1 to 7 patient encounters per day with a mean length of stay of 11 days.

Six services (67%) had a policy stipulating an upper age limit for patients who could be admitted to the children’s hospital. These patient age limits ranged from 21 to 35 years old. All 6 of these programs indicated exceptions existed to the policy age limit. Reasons for exceptions included specific childhood-onset conditions (eg, congenital heart disease, malignancy on a pediatric protocol, or weighing less than 40 kg) and/or division or hospital leadership approval.

There were a variety of patient diagnoses seen by each adult inpatient service. The 5 most common were neurodevelopmental disorders, congenital heart disease, metabolism and genetic disorders, pediatric malignancies, and pulmonary or chronic respiratory disorders.

The 5 clinical services that most used the adult inpatient consult service were pediatric cardiology, hospital medicine or general pediatrics, pediatric hematology and oncology, pediatric ICU, and pediatric pulmonology. Seven (78%) adult inpatient services indicated that other adult subspecialty consult services were available.

All services reported that Med-Peds physicians comprised their clinical staff (Table 2). Five (56%) had internal medicine physicians as well. The majority (n = 6, 67%) used home call for night coverage of the adult inpatient service. Further information about staffing and coverage models can be found in Table 2.

Participants from all 10 surveyed institutions completed interviews, including the institution with only financial approval to start an adult inpatient service. Given this institution’s expectation of an active service within the year, their interview responses were additive to our understanding of facilitators and barriers to service creation. Themes and explanations are below with illustrative quotes provided in Table 3. Themes were grouped into 3 larger categories: (1) facilitators to development, growth, and sustainability; (2) barriers to development, growth, and sustainability; and (3) Both a barrier and facilitator to development, growth, and sustainability.

Each participant identified access to specialized clinical services as a reason for keeping adults at their pediatric institutions. Examples included high-intensity chemotherapy protocols for malignancies only offered at pediatric hospitals and multidisciplinary teams with pediatric-trained cardiothoracic surgeons and adult congenital heart disease specialists for congenital heart disease. Pediatric-trained providers often then needed support identifying and addressing comorbidities more commonly seen in adults (eg, hypertension and type 2 diabetes) to ensure quality care. Some participants noted that there had been near-miss safety events for adult patients who ignited efforts to ensure patient safety and quality care for adults hospitalized at their pediatric institutions.

Engagement of key stakeholders from the initial development through continuation of the adult inpatient service was highlighted by all participants as a facilitator for creation and sustainability. Participants identified that integration of the adult inpatient service into their pediatric institution’s safety culture was a vital benefit. For example, 1 participant noted a physician representative from their service joined the hospital-wide safety huddles twice daily to specifically address issues with admitted adult patients. Although serious issues with admitted adult patients were rare events, reliable availability was cited as one way participants continued advocating for using their service and promoting safe care for hospitalize adults. Most participants noted that their adult inpatient services increased overall system situational awareness around hospitalized adults. This increased awareness was facilitated by general presence of the service, as well as more specific educational efforts through adult emergency simulations.

All adult inpatient services included Med-Peds physicians who could function as experts in both pediatric and adult medicine. Their role in the pediatric institution functioned as a specialty consult where general internal medical knowledge was applied. Many participants felt there was a special application of Med-Peds “dual” knowledge to the adult-aged population at their institutions. For example, physicians staffing these services would medically manage conditions more commonly seen in adults (eg, essential hypertension, pulmonary embolism, type 2 diabetes mellitus). Several participants identified that these adult inpatient services helped patients navigate complicated and disjointed pediatric and adult health systems. The Med-Peds “dual” knowledge was seen to apply again, as this navigation required knowledge of the services and specialties offered within each hospital system. For example, these service physicians were able to identify teams that could provide procedural interventions that might only be offered at either the adult or pediatric hospital.

The adult inpatient services supported a pediatric-trained workforce to adapt care for age groups normally not cared for by their staff. The specific supports needed varied between pediatric institutions depending on the prevalent patient populations. Sometimes that meant even extending the service across both the pediatric and adult institutions, offering the internal medicine-aimed care in the pediatric hospital and a more pediatric-aimed care (such as in the care of adults with neurodevelopmental disabilities) in the adult setting. This system adaptability was leveraged by many pediatric institutions during the coronavirus disease 2019 (COVID-19) pandemic by being able to offload specific adult populations from proximate adult health systems.

Participants explained that their pediatric institutions had specialized care, or centers, for certain conditions. This phenomenon resulted in more adult-aged patients continuing their care at the pediatric institution. Congenital heart disease was commonly cited both as the patient population that prompted adult inpatient service development, as well as the most common clinical service to consult. Participants noted their pediatric institutions intentionally built multidisciplinary teams with pediatric cardiothoracic surgeons and adult congenital heart specialists. Adults with severe intellectual and developmental disabilities were also referenced as a population that continued care in the pediatric institution because of their medical complexity. Participants felt the patient volume seen with these conditions allowed development and maintenance of needed clinical expertise that was recognized by patients, their families, and communities alike. This centralization of clinical knowledge was seen to contribute to the creation and sustaining forces of the adult inpatient service.

Most participants identified that these services, especially as a consult-only model, did not consistently have the patient numbers to be fiscally sustainable based on relative value units alone. Yet, all had found other compelling reasons to create the adult inpatient service. Participants explained that using outcomes illustrating return on investment was more helpful to gain and maintain institutional buy-in. Some participants continue to require funding through grants or from donor-funds to sustain or grow their services. Billing and relative value unit generation were seen as at least partially supportive. However, most participants (n = 6, 67%) either double-covered the adult inpatient consult service and another hospital-based admitting service or were the primary admitting service for another service.

The need for stakeholder engagement was noted to continue throughout all stages of adult inpatient service development, growth, and sustainability. Leadership turnover sometimes meant starting over in making the case of the adult inpatient consult service. This was a time intensive process and was cited as a barrier to creation and growth. Many respondents identified 1 or more stakeholders at their institution who continued to require repeated engagement to justify continued financial and/or operational support or appropriately use their adult inpatient service.

Most participants described their adult inpatient services as support mechanisms for the pediatric to adult healthcare transition. Although less than half of the adult inpatient services were created to address transition, all found they were increasingly called to coordinate transitional aspects of care. Only some (n = 3) were associated with transitional care outpatient programs. This connection with outpatient transitional care “homes” allowed the adult inpatient service to extend transition work already started. This connection also improved communication between patients and their outpatient transition providers. As a result, some institutions reported improved rates of patients transferring hospital care to adult institutions. Institutional leadership noted these improved transfer rates, which increased the perceived value of having adult services available in the pediatric hospital.

Conversely, adult inpatient services without any associated structured outpatient transitional care program found themselves limited in their ability to address transition-related issues despite their respective institutional expectations. Participants noted this could lead to negative patient experiences as well as decreased perceived value by other clinicians of the adult inpatient service.

Adult inpatient services were found to exist predominantly at free-standing children’s hospitals to fill a clinical care gap for adults with childhood-onset conditions hospitalized in their respective pediatric institutions. The 9 currently active services had great variability between program characteristics (eg, longevity, staffing resources) that participants attributed to varying patient population needs and institutional expertise. Despite this variation, we found common barriers and facilitators to adult inpatient service development, growth, and subsequent sustainability. Despite challenges demonstrating financial viability, participants overwhelmingly cited pediatric institutional value of clinical expertise that facilitated safe and quality care of adults with chronic conditions of childhood as a key facilitator.

Nine of the 10 identified adult inpatient services were at free-standing children’s hospitals. Therefore, at the time of writing, these services are present at 23% of free-standing children’s hospitals in the United States.¹⁵  The longevity (up to 17 years) and prevalence of these services is not surprising given what we know from available evidence. Namely, that the presence of adults in children’s hospitals has been known for years and continues to increase.^1,16  Free-standing children’s hospitals have distinct challenges that arise when caring for admitted adult patients because of the relative lack of adult medicine accessibility. Most study participants highlighted their adult inpatient service was created to fill this adult medicine clinical care gap at their pediatric institutions. From a patient safety perspective, this is particularly troublesome when these pediatric systems may lack capacity to identify and/or address adult-related emergencies (eg, acute coronary syndrome or stroke).^17,18  If free-standing children’s hospitals and other pediatric institutions continue to hospitalize adults, the presence of an adult inpatient service may be one structural tool improve the safe care of this population.

Adult inpatient services allow pediatric institutions more flexibility in caring for adults. Pediatric institutions have not been alone in their development of services aimed at caring for these adult populations; adult institutions have as well.^7–9  Despite increasing numbers of adults with childhood-onset conditions living well into adulthood, there are no clear clinical “best practices.” The incidence and prevalence of coexisting conditions, like hypertension, diabetes, and coronary artery disease, for this population of adults is unknown, which increases the challenges health systems and patients alike face when determining the best location of hospital care. For most adults with childhood-onset conditions, there is likely equipoise between receiving hospital care in an adult or pediatric system.^19,20  Some evidence suggests that cost and length of stay may be higher for adults with childhood-onset conditions when they are admitted to pediatric institutions.²¹  Taken together, our participants voiced that there are specific circumstances when adults should be hospitalized in a pediatric institution. It will be critical moving forward for pediatric institutions to first evaluate existing care quality and pediatric to adult healthcare transition supports before creating adult inpatient services.^22,23 

Med-Peds hospitalists were unanimously identified as core staff of these adult inpatient services. Participants cited that dual-trained physicians have specific knowledge relevant to the care of hospitalized adults in pediatric institutions. First, these physicians are able address both pediatric and adult-based medical concerns. Second, Med-Peds physicians have systems-based knowledge of both their pediatric and adult institutions (eg, understanding what procedures can be done where and for whom). These combined areas of expertise enable anticipation of clinical care gaps, identification of possible safety concerns, and navigating issues that arise from complex pediatric conditions. This makes physicians trained in both pediatric and adult medicine, and indirectly adult inpatient services in pediatric institutions, uniquely equipped to navigate complex patient needs within and between pediatric and adult health systems. As pediatric institutions make decisions about admission capacity for adult patients, hospitalists with both pediatric and adult medical and systems knowledge (ie, Med-Peds and Family Medicine) should play an integral part in ensuring quality age- and condition-appropriate care. Internists were part of clinical staffing of at least 1 adult inpatient consult service after additional training in childhood-onset conditions and the pediatric health system. Importantly, transition experts identify that a hospitalization is not the ideal time to navigate transition.²⁴  However, our work shows that the role of the inpatient team can bolster-not replace-ongoing system-wide transition efforts to help patients have a successful transition process, acting as a “transition advocate” for patients and families in need.²⁵ 

Fiscal viability was the major barrier of the adult inpatient services. Even though pediatric institutions are seeing increasing numbers of adults, these adult patient volumes are still relatively low.¹  Combined with time and care coordination intensity, a fee for service and relative value unit based healthcare system did not allow for fiscal sustainability. Participants from adult inpatient services established for at least a few years recognized that leadership buy-in and use of other return on investment metrics (eg, qualitative feedback from patients and other healthcare team members) facilitated both service creation and sustainability. This suggests that pediatric institutions with less financial resources may be less able to create such an adult inpatient consult service. Many pediatric institutions now actively recruit adults with congenital heart disease,²⁶  with the hope that these programs will be revenue-generating for pediatric health systems.^27,28  Participants in our study emphasized that adult medicine expertise must be available to safely care for these adult populations in pediatric settings and support these revenue generating services. Although outcome measures were not specifically requested, programs did report that monitoring mortality and transition into adult healthcare systems were considered added value to their pediatric institutions. The coming era of value-based payment models may mitigate some barriers to the creation and sustainability of adult inpatient consult services given the added healthcare value for these specific patient populations.

This study has a few limitations. First, we were unable to determine a response rate as it is unknown how many adult inpatient services currently exist in pediatric institutions. However, we anticipated a small number of active inpatient services, intentionally using purposive and snowball sampling. Second, only designated leaders of active adult inpatient services were included. Next steps to further understanding of facilitators and barriers of creating and sustaining these adult inpatient services need to include additional stakeholders, such as patients and health system leaders. Third, we cannot say if the presence of these adult inpatient services improves care quality for adults hospitalized in pediatric institutions. Despite these limitations, our study highlights that adult inpatient services are present in pediatric institutions, are predominantly staffed by Med-Peds physicians, and are one way pediatric institutions aim to provide age- and condition-appropriate care for adult patients.

At least 10 pediatric institutions in the United States have adult inpatient services that support the clinical care of adults hospitalized in pediatric settings. Value for these adult inpatient services is perceived by service leaders and their supporting pediatric institutions, but fiscal viability remains a challenge. These adult inpatient services have unique attributes, including their design to address specific needs of adult patient populations receiving inpatient care at pediatric institutions. Med-Peds physicians are core staff for these adult inpatient services in pediatric institutions, bridging clinical care and operational gaps that require both pediatric and adult medical and systems-based knowledge.