A Methodological Framework for the Integrated Design of Decision-Intensive Care Pathways—an Application to the Management of COPD Patients

Abstract

Healthcare processes are by nature complex, mostly due to their multidisciplinary character that requires continuous coordination between care providers. They encompass both organizational and clinical tasks, the latter ones driven by medical knowledge, which is inherently incomplete and distributed among people having different expertise and roles. Care pathways refer to planning and coordination of care processes related to specific groups of patients in a given setting. The goal in defining and following care pathways is to improve the quality of care in terms of patient satisfaction, costs reduction, and medical outcome. Thus, care pathways are a promising methodological tool for standardizing care and decision-making. Business process management techniques can successfully be used for representing organizational aspects of care pathways in a standard, readable, and accessible way, while supporting process development, analysis, and re-engineering. In this paper, we introduce a methodological framework that fosters the integrated design, implementation, and enactment of care processes and related decisions, while considering proper representation and management of organizational and clinical information. We focus here and discuss in detail the design phase, which encompasses the simulation of care pathways. We show how business process model and notation (BPMN) and decision model and notation (DMN) can be combined for supporting intertwined aspects of decision-intensive care pathways. As a proof-of-concept, the proposed methodology has been applied to design care pathways related to chronic obstructive pulmonary disease (COPD) in the region of Veneto, in Italy.

Appendix A: Modeling COPD Subprocesses

1.1 A.1 COPD Diagnosis and Assessment

Diagnosis of COPD has to take into account a multiplicity of signs and symptoms. A clinical diagnosis of COPD should be considered in any patient who has dyspnea, chronic cough or sputum production, and presents a history of exposure to risk factors for the disease [23]. Among genetic disorders that must be considered in a diagnosis of COPD, the best documented is α ₁-antitrypsin deficiency, which leads to an increased predisposition to obstructive pulmonary disease [106].

Spirometry is required by international clinical guidelines to make a diagnosis of COPD [23, 57]. Practically, a spirometer measures how quickly full lungs can be emptied and the total volume of air expired. Spirometric measurements used in a diagnosis of COPD include:

• Forced vital capacity (FVC), which is the maximum volume of air that can be exhaled during a forced maneuver.

• Forced expired volume in one second (FEV ₁), which is volume expired in the first second of maximal expiration, during a forced maneuver. This value measures how quickly lungs can be emptied.

• FEV ₁/FVC, which is the ratio between the two previously calculated values. FEV ₁ is expressed as a percentage of the FVC and gives an indication of airflow limitation, called Tiffenau index [23].

Spirometry results are evaluated by comparison with reference values calculated on healthy subjects and depending on age, height, gender, and ethnicity.

Currently, the spirometric criterion used for diagnosing COPD is a post-bronchodilator FEV ₁/FVC ratio below 0.7. Bronchodilators are medications that increase the FEV ₁ or change the other spirometric variables, by altering airway smooth muscle tone. Performing spirometry after the administration of a short-acting inhaled bronchodilator helps to differentiate between an acute or persistent obstructive defect and minimizes outcome variability [23]. However, the aforementioned threshold is age-dependent and can lead to a significant degree of overdiagnosis in the elderly and of underdiagnosis in younger patients. Besides, as multiple respiratory diseases present a FEV ₁/FVC ratio < 0.70, differential diagnoses must be considered in order to determine an appropriate treatment [107]. Chest X-rays may be prescribed to confirm a working diagnosis of COPD and questionnaires such as the COPD assessment test (CAT) are administered for assessing symptoms. Indeed, when used in conjunction with spirometry results and demographic data, these tools have proven to enhance diagnostic accuracy [59].

For grading COPD severity, spirometric classification remains the preferred standard method [23]. Post-bronchodilator lung function, expressed in terms of FEV ₁ and FEV ₁/FVC ratio, is used to classify COPD patients into four levels of severity [23], summarized in Table 2. Patients showing a post-bronchodilator Tiffenau index greater than 0.70 are not considered in COPD management, despite those who smoke or have exposure to pollutants are considered at risk and may be targeted by prevention programs.

Table 2 Levels of COPD severity, based on spirometric assessment, taken from [23]

The BPMN process corresponding to COPD diagnosis and assessment, depicted in Fig. 6, consists of a main pool, which stands for the regional healthcare system. This is partitioned into two lanes, one representing a primary care unit and, specifically, a general practitioner, the other one representing a pulmonologist working in a regional hospital.

Since one of the goals of the COPD process models is to define the respective responsibilities of general practitioners and pulmonary specialists, only these two roles have been represented explicitly. Indeed, practitioners and pulmonologists have to supervise the performance of nurses, technicians, and auxiliary personnel who collaborate in the process.

The process begins when the patient consults the general practitioner, typically after having experienced some sort of respiratory discomfort, such as productive cough, acute chest pain or breathlessness. Case history and working diagnosis is the first decision activity encountered, modeled as a user task, which represents the gathering of useful observations during medical inspection that are analyzed in conjunction with the patient clinical history and exposure to risk factors in order to formulate a working diagnosis of COPD.

All the collected information regarding symptoms, smoking habits, and risk factors is recorded in the local PCU database.

The following exclusive gateway, COPD Suspected? directs the flow toward the prescription of spirometry and further examinations, if a diagnosis of COPD is considered, or toward the process end event, otherwise. Spirometry (in PCU)/Spirometry (in hospital) is indicated to support COPD diagnosis, to assess the severity of airflow obstruction and, in some cases, it can be used as a prognostic indicator. If patients in primary care have direct access to spirometers, a simple spirometry test is requested and performed by a general practitioner directly within a primary care facility. Otherwise, patients need a prescription for the spirometry to be performed in hospital.

Under an organization standpoint, the biggest difference between the performance of a spirometry in PCU or in hospital is waiting time. Whereas in PCU, spirometric assessment can be executed during a routine examination, spirometers in hospitals are used for assessing various respiratory problems and patients are prioritized according to the severity of their conditions.

Chest X-rays may also be carried out in hospital, if believed necessary to support the diagnostic process. Spirometry allows measuring FEV ₁, FVC, and the ratio between such values. The physician must read and record spirometry results received with the corresponding reports, and compare them with reference values for age, weight, height, gender, and ethnicity. If airflow obstruction is detected, the practitioner must prescribe post-bronchodilator spirometry (PBS) to confirm the diagnosis of COPD and to measure the degree of airflow obstruction and its reversibility. Once the patient has been informed and advised about the conduct of the test, post-bronchodilator spirometry is performed by a pulmonologist in hospital. Subsequently, the pulmonologist must write PBS report, containing the diagnostic statement and the spirometric results. This is sent to the general practitioner, who must confirm the diagnosis of COPD and record the patient data in the primary care unit database, following the ICD-9-CM coding rules [108]. The general practitioner can also prescribe pharmacological treatment, whenever considered necessary to relieve the patient from symptoms. Then, the COPD assessment test (CAT) is administered to gather information about the impact of COPD on the patient’s quality of life and to measure general health status impairment. If the patient is a smoker, additional tests, i.e., Mondor and Fagerstörm, are administered to reveal addiction to tobacco consumption and nicotine [109].

Once the test-based assessment is concluded, the physician needs to Inform the patient about his/her clinical condition and can suggest a detoxing treatment in specialized facilities for smoking cessation. Then, the patient undergoes a pulmonary examination in hospital, which results in COPD staging, based on the outcomes of the previously executed spirometric assessment. The staging report is authored by the pulmonologist and must contain the assessed COPD stage, the value of the Tiffenau index, an indication for medical examinations and future re-evaluations, and therapeutic advice. The general practitioner receiving the report must verify that the assessed stage is correct before proceeding with COPD stage recording as he/she is responsible for signaling possible incongruities. Indeed, the classification of COPD patients is a crucial decision as the planning of the future inspections, both in terms of the kind of medical analyses required and their frequency, depends on the severity of the assessed grade. If the patient is in stage 3, a pulmonary specialist in hospital is put in charge of monitoring the patient. In this case, the pulmonologist must prescribe pharmacological therapy, schedule pulmonary examination, schedule post-bronchodilator spirometry, and schedule 6-min walk test (6MWT) to monitor the disease, and to evaluate the patient’s functional exercise capacity. Conversely, if the patient is assessed with stage 1 or stage 2, PCUs remain in charge of COPD management. PCUs must also provide a counseling service in order to educate patients to avoid exposure to behaviors that can further compromise their health condition. The progression of the disease can be limited by efficient monitoring and changes in lifestyle and smoking habits. In the final stage of COPD assessment, the general practitioner needs to schedule dietitian consultation if the patient presents a BMI greater than 30. Finally, he/she has to plan vaccinations (influenza and pneumococcus), as they appear to be effective in older and severe patients [23]. Once the main steps of the care intervention have been scheduled, the COPD diagnosis and assessment process terminates.

1.2 A.2 Ordinary Management of Stable COPD

Life-long and continuous management of stable COPD can become quite complex especially in advanced stages of the disease, as multiple complications have to be considered beside compromised pulmonary function. In particular, patients affected by COPD suffer from impaired gas exchange and are subjected to develop cardiovascular, metabolic, and neoplastic comorbidities [23].

Therefore, COPD treatment aims to prevent the progression of the disease, relieve patient symptoms, improve exercise tolerance and general health status, and prevent and treat correlated complications. The type of care workers in charge of COPD management and the frequency of medical inspections depend on the severity of the disease, on the patient individual response to pharmacological treatment, and on the healthcare system. Ordinary management of COPD encompasses the following important aspects: smoking cessation, optimization of pulmonary status by pharmacological therapy, improvement of exercise tolerance, nutritional care, and possible support in terms of oxygen therapy or pulmonary ventilation. Besides, education, social, and behavioral aspects must be considered to improve compliance [57]. Vaccinations can be required, based on local policies, availability, and affordability [23]. Influenza and pneumococcal vaccinations are planned yearly, to prevent the insurgence of serious illnesses that may contribute to COPD exacerbations.

Ordinary management of COPD is based on individualized assessment and aims to reduce both current symptoms and risk of sudden worsening [23]. As previously mentioned, the BPMN diagram representing the main steps of ordinary management of COPD, depicted in Fig. 7, is executed with a periodicity that depends on assessed COPD stage. This periodicity is captured by a start timer event. Specifically, the process is expected to start every 2 years for patients in stage 1, every year for patients in stage 2, and every 6 months or less for patients in stage 3.

The first steps of the care process are executed either by the general practitioner, for patients in stage 1 and 2, or by the pulmonologist, for patients in stage 3, but the conduct of the explained actions coincides. Firstly, it is necessary to verify administered vaccinations. In the studied context, vaccinations are managed by district health authorities. If vaccinations have not been administered, the physician must re-schedule vaccinations. If the patient refuses to be vaccinated, the motivation behind the refusal must be recorded in the health authority information system HC district db. In the studied context, data suggest that elderly patients often forget to attend vaccination appointments or they have troubles reaching care facilities, due to mobility limitations. In this latter case, vaccinations can be provided at home, depending on local service availability.

To monitor the disease, care providers are required to administer COPD assessment test (CAT) and to adjust current bronchodilator therapy, if needed. Pharmacological therapy is prescribed according to the severity of the illness, the availability of the drugs, and the presence of comorbidities. Treatment regimen should be patient-specific as the relationship between the severity of symptoms and airflow obstruction tends to vary from patient to patient. Moreover, COPD severity is also dependent on the geographical distribution of the population. Usually, patients in stage 1 are treated with short-acting inhaled bronchodilators, while long-acting bronchodilators are prescribed to patients in stage 2 or 3, in different dosage and combinations.

Then, different inspections are carried out in parallel, to evaluate the patient’s health status, and re-assess BMI and respiratory function. Mondor and Fagerstörm tests are administered in order to evaluate lifestyle and smoking habits, with the aim to assess the patient’s progress toward smoking cessation. Physicians must also evaluate dyspnea and exercise tolerance. The objective measurement of exercise impairment is obtained with the help of the 6-min walk test [24]. This is used in conjunction with the Modified British Medical Research Council (mMRC) dyspnea questionnaire to quantify the degree of disability due to breathlessness during daily activities. Body mass index (BMI) must also be re-assessed, in order to decide if it is necessary to Prescribe a dietitian consultation. Obesity and weight loss, when combined with muscle wasting, contribute significantly to morbidity, disability, and handicap in COPD patients, who must receive nutritional therapy. Pulse oximetry is used to evaluate oxygen saturation. If the measured oxygen saturation is less than 92%, blood gas assessment is scheduled. Arterial blood gas analysis (ABG) is the preferred method for determining the need of oxygen therapy [57]. Finally, the patient is examined and all analyses results are resumed and recorded in the dedicated information system PCU db.

If the patient is assessed with stage 2 or stage 3, he/she might necessitate an additional pulmonary inspection. In this case, a pulmonologist can request oxygen therapy according to the considered clinical picture. Long-term oxygen therapy is usually administered continuously and in a home-care setting to improve survival, exercise, sleep, and cognitive performance. In addition, a cardiological consult may be requested, to exclude cardiovascular instability. Finally, the pulmonologist must review COPD stage in order to confirm the stage after treatment or to update it. At the end of each instance of the COPD ordinary management process, the general practitioner must either confirm COPD stage or update COPD stage, if this has changed. In case of stage change, signal event re-schedule is thrown to be caught by the corresponding interrupting boundary event, depicted in Fig. 5 and attached to the border of sub-process management of COPD exacerbations.

The introduced healthcare process representing the ordinary management of stable COPD is periodically re-enacted and the patient is also involved in educational programs to improve recognition of symptoms worsening and self-care.

1.3 A.3 Management of COPD Exacerbations

COPD exacerbations are “acute episodes characterized by a sudden worsening of the patient respiratory symptoms that is beyond expected day-to-day variations” [110]. The main drawback associated with COPD exacerbations is represented by hospital admissions, that negatively impact the disease evolution, economical costs, and quality of life [67].

Several clinical findings must be considered when evaluating patients with exacerbations. Among these COPD severity, the presence of comorbidities, and the history of previous exacerbations are the most important. Indeed, patients that are subjected to two or more exacerbations of COPD per year seem to maintain this worsening trend over time and, thus, must be constantly monitored. A diagnosis of exacerbation requires a physical examination to evaluate the effects of the episode on both cardiovascular and respiratory systems [23].

COPD exacerbations are often treated with temporary short-acting inhaled beta2-agonists, which can be combined with corticosteroids and antibiotics. However, if the patient does not respond to outpatient pharmacological treatment, hospitalization is required. When a patient is admitted to hospital, supplementary oxygen is administered, short-acting bronchodilators are prescribed, and pulmonary rehabilitation may also be indicated [57].

COPD hospital admissions due to exacerbations negatively affect the patient quality of life and the progression of the illness, while substantially increasing the costs of patient management [67]. However, a standardized and integrated care intervention, supported by proper data collection, and resource coordination, seems to effectively prevent hospitalizations due to exacerbations in COPD patients [67, 111].

The goal of exacerbation treatment is to minimize the effects of the on-going worsening and prevent future episodes. The process enacted for treating COPD exacerbations in Veneto is depicted in Fig. 8.

An exacerbation episode is usually detected by the general practitioner, following the clinical presentation of the patient, who complains of an acute change of symptoms. Diagnosis of exacerbation relies on the current symptoms, on the evidence gathered during the physical examination with pulse oximetry, and on the history of previous worsening episodes. If more than two exacerbations occur within 1 year, the stage of the disease is expected to vary, as the patient respiratory function is compromised more rapidly [57]. In general, diagnosing an exacerbation can become quite cumbersome, as multiple physical findings and diagnostic procedures must be evaluated, with the main aim of excluding the development of comorbidities. If oxygen saturation measured with pulse oximetry is < 90%, the exacerbation is likely to be life-threatening and, thus, hospital and intensive care treatment is indicated. Otherwise, the general practitioner can suspend current therapy in order to begin therapy to oppose worsening. Usually, short-acting beta agonists (SABA), short-acting muscarinic antagonists (SAMA), inhaled corticosteroids, and antibiotics are prescribed, according to the considered clinical picture. Then, after 24/48 h, the patient is re-evaluated. Following clinical diagnosis, gateway Is exacerbation life-threatening? determines if the patient needs to be treated in inpatient or outpatient settings. If the patient has improved, the exacerbation can be managed in an outpatient setting. In these circumstances, it is indicated to continue with current therapy and to schedule periodic examinations to ensure proper patient monitoring. If the patient has not improved after treatment or oxygen saturation is assessed < 90%, he/she is sent to the hospital emergency room. Hospitalization must be considered when the patient cannot been treated adequately in home care settings, due to the severity of the respiratory dysfunction [23, 57]. Following ER triage, ER physicians must test hydration level to ensure proper fluid balance and they need to assess symptoms. Then, the patient is physically examined and continuously monitored. Physicians in ER must exclude other clinical complications, such as heart failure, bronchial pneumonia, pulmonary embolism, and pleural effusion. A pulmonologist examination in ICU can be requested to assess arterial blood gases and execute chest radiography. If the severity of respiratory dysfunction is high, the patient must be admitted to an intensive care unit and treated under the responsibility of a pulmonologist. Different factors must be considered when evaluating hospitalization. Typically, patients are admitted in ICU when COPD symptoms are acute, there is a preponderance of sensory disturbances, there is evidence of new cardiac arrhythmia, or no response to exacerbation treatment is observed [23]. The treatment to solve exacerbation is mostly based on oxygen therapy, which aims to prevent tissue hypoxaemia, i.e., reduced oxygen availability, and at preserving cellular oxygenation. During hospitalization, the general practitioner is informed about the administered care. This is necessary to provide practitioners with all the information, needed to optimally treat the patient after hospital discharge. Patient discharge is decided after evaluating several criteria, which consider also local policies and availability. The discharge report must contain information regarding the possibly changed COPD stage, respiratory function, comorbidities, outpatient suggested therapy, and clinical follow-up. Patients dismissed with hypoxemia or in stage 3 may require short-term or long-term oxygen therapy. In this case, a pulmonologist must take the patient in charge and a home-care oxygen therapy protocol is started. Oxygen therapy is monitored by specialized centers in the region and its efficacy must be re-evaluated yearly.

As required by the national program for the evaluation of care outcomes, 2 weeks after patient discharge, the general practitioner must verify treatment efficacy and effectiveness. The aforementioned evaluation program aims to estimate the overall quality of the provided care, in terms of treatment costs, appropriateness, and efficacy, in order to compare the outcomes of the overall care intervention with audit and bench-marking data. Hospital re-admission of COPD patients within 30 days from discharge is probably the most important indicator used for assessing the quality of the overall care plan [67, 112]. In the studied context, around 15% of discharged patients is re-hospitalized within 30 days from discharge. During this final verification phase, the stage of COPD is also reviewed and, if it has changed as a consequence of the exacerbation, signal state changed is thrown. This is caught by the corresponding non-interrupting boundary event attached to the border of sub-process management of COPD exacerbation of Fig. 5, which enables an exception flow devoted to the rescheduling ordinary examinations. Likewise ordinary management of COPD, exacerbations require follow-up. This includes reassessment within 4 weeks, evaluation of improvement in symptoms, physical examination, assessment of need for oxygen therapy, and re-adjustment of current treatment regimen.