Implementation of an emergency department triage procedure for the detection and isolation of patients with active pulmonary tuberculosis

Implementation of Prediction Models in the Emergency Department from an Implementation Science Perspective-Determinants, Outcomes, and Real-World Impact: A Scoping Review

STUDY OBJECTIVE

Prediction models offer a promising form of clinical decision support in the complex and fast-paced environment of the emergency department (ED). Despite significant advancements in model development and validation, implementation of such models in routine clinical practice remains elusive. This scoping review aims to survey the current state of prediction model implementation in the ED and to provide insights on contributing factors and outcomes from an implementation science perspective.

METHODS

We searched 4 databases from their inception to May 20, 2022: MEDLINE (through PubMed), Embase, Scopus, and CINAHL. Articles that reported implementation outcomes and/or contextual determinants under the Reach, Effectiveness, Adoption, Implementation Maintenance (RE-AIM)/Practical, Robust, Implementation, and Sustainability Model (PRISM) framework were included. Characteristics of studies, models, and results of the RE-AIM/PRISM domains were summarized narratively.

RESULTS

Thirty-six reports on 31 implementations were included. The most common prediction models implemented were early warning scores. The most common implementation strategies used were training stakeholders, infrastructural changes, and using evaluative or iterative strategies. Only one report examined ED patients' perspectives, whereas the rest were focused on the experience of health care workers or organizational stakeholders. Key determinants of successful implementation include strong stakeholder engagement, codevelopment of workflows and implementation strategies, education, and usability.

CONCLUSION

Examining ED prediction models from an implementation science perspective can provide valuable insights and help guide future implementations.

Individual and public health consequences associated with a missed diagnosis of pulmonary tuberculosis in the emergency department: A retrospective cohort study

Objectives

To determine: i) the emergency department (ED) utilization history of pulmonary tuberculosis (PTB) patients, and ii) the potential individual and public health consequences of a missed diagnosis of PTB in this setting.

Design

Retrospective observational cohort study.

Participants

Patients with PTB aged >16 years diagnosed between April 1, 2010 and December 31, 2016 in the Province of Alberta, Canada.

Methods

We identified valid new cases of PTB from a provincial registry and linked them to ED attendees in administrative databases. Visits are considered ‘PTB’, pulmonary ‘other’, and non-pulmonary based on the most responsible discharge diagnosis. Individual consequences of a missed diagnosis included health system delay and PTB-related death; public health consequences included nosocomial ED exposure time and secondary cases.

Results

Of 711 PTB patients, 378 (53%) made 845 ED visits in the six months immediately preceding the date of diagnosis. The most responsible ED discharge diagnosis was PTB in 92 (10.9%), pulmonary ‘other’ in 273 (32%) and non-pulmonary in 480 (56.8%). ED attendees had a median (IQR) health system delay of 27 (7,180) days and, compared to non-ED attendees were more likely to die a TB-related death 5.9% vs 1.2%, p = 0.001. Emergency attendees generated 3812 hours of ED nosocomial exposure time, and 31 secondary cases (60.8% of all secondary cases reported). Mycobacterium tuberculosis isolates from ED-attendees were more likely than non-attendees to be clustered–i.e., have an identical DNA fingerprint with another isolate (27% vs. 21%, p = 0.037).

Conclusions

ED utilization by PTB patients, and related consequences, are substantial. EDs are a potential resource for earlier PTB diagnosis.

Pulmonary tuberculosis: An analysis of isolation practices and clinical risk factors in a tertiary hospital

BACKGROUND

Inadequate isolation of patients with active pulmonary tuberculosis causes exposure whereas over-cautious isolation generates time and cost inefficiencies. This study aims to ascertain the delays involved in isolating subjects and the importance of risk factors.

METHODS AND MATERIAL

Between December 2010 and January 2013, a retrospective analysis of 271 subjects was performed. Information was obtained from discharge letters, radiological and microbiological results.

RESULTS

The median time taken to isolate subjects was 0 days, and 71.7% were isolated within 1 day. Most subjects (75.3%) had sputum samples obtained after isolation, of which 14.7% were positive. The median time from admission to first sputum sample was 1 day. Smear was negative in 174 subjects (85.3%). Country of birth (high or low risk) did not significantly affect sputum positivity (25.5% vs 19.4%, p=0.52). Suspicious radiological findings were noted in 38.6% subjects, and 32.8% had a suspicious clinical history. Subjects with both clinical and radiological probability had more sputum positivity (46.2%), compared to subjects who had neither (2.7%).

CONCLUSION

There are delays with isolation and diagnosis of subjects with a high probability of tuberculosis. Clinical and radiological probability were more significant in predicting sputum positivity than country of birth.

Improving natural ventilation in hospital waiting and consulting rooms to reduce nosocomial tuberculosis transmission risk in a low resource setting

Background

TB transmission in healthcare facilities is an important public health problem, especially in the often-overcrowded settings of HIV treatment scale-up. The problem is compounded by the emergence of drug resistant TB. Natural ventilation is a low-cost environmental control measure for TB infection control where climate permits that is suited to many different areas in healthcare facilities. There are no published data on the effect of simple structural modifications to existing hospital infrastructure to improve natural ventilation and reduce the risk of nosocomial TB transmission.

The purpose of this study was to measure the effect of simple architectural modifications to existing hospital waiting and consulting rooms in a low resource setting on (a) improving natural ventilation and (b) reducing modelled TB transmission risk.

Methods

Room ventilation was measured pre- and post-modification using a carbon dioxide tracer-gas technique in four waiting rooms and two consulting rooms in two hospitals in Lima, Peru. Modifications included additional windows for cross-ventilation (n = 2 rooms); removing glass from unopenable windows (n = 2); creation of an open skylight (n = 1); re-building a waiting-room in the open air (n = 1). Changes in TB transmission risk for waiting patients, or healthcare workers in consulting rooms, were estimated using mathematical modelling.

Results

As a result of the infrastructure modifications, room ventilation in the four waiting rooms increased from mean 5.5 to 15; 11 to 16; 10 to 17; and 9 to 66 air-changes/hour respectively; and in the two consulting rooms from mean 3.6 to 17; and 2.7 to 12 air-changes/hour respectively. There was a median 72% reduction (inter-quartile range 51–82%) in calculated TB transmission risk for healthcare workers or waiting patients. The modifications cost <US$75 in four rooms, and US$1000 and US$7000 in the remaining two rooms.

Conclusions

Simple modifications to existing hospital infrastructure considerably increased natural ventilation, and greatly reduced modelled TB transmission risk at little cost.

Longer hospital stay is associated with higher rates of tuberculosis-related morbidity and mortality within 12 months after discharge in a referral hospital in Sub-Saharan Africa

Background

Nosocomial transmission of pulmonary tuberculosis (PTB) is a problem in resource-limited settings. However, the degree of TB exposure and the intermediate- and long-term morbidity and mortality of hospital-associated TB is unclear. In this study we determined: 1) the nature, patterns and intensity of TB exposure occurring in the context of current TB cohorting practices in medical centre with a high prevalence of TB and HIV; 2) the one-year TB incidence after discharge; and 3) one-year TB-related mortality after hospital discharge.

Methods

Factors leading to nosocomial TB exposure were collected daily over a 3-month period. Patients were followed for 1-year after discharge. TB incidence and mortality were calculated and logistic regression was used to determine the factors associated with TB incidence and mortality during follow up.

Results

1,094 patients were admitted to the medical wards between May 01 and July 31, 2010. HIV was confirmed in 690/1,094 (63.1%) of them. A total of 215/1,094 (19.7%) patients were diagnosed with PTB and 178/1,094 (16.3%) patients died during the course of their hospitalization; 12/178 (6.7%) patients died from TB-related complications. Eventually, 916 (83.7%) patients were discharged and followed for one year after it. Of these, 51 (5.6%) were diagnosed with PTB during the year of follow up (annual TB rate of 3,712 cases per 100,000 person per year). Overall, 57/916 (6.2%) patients died during the follow up period, of whom 26/57 (45.6%) died from confirmed TB. One-year TB incidence rate and TB-associated mortality were associated with the number of days that the patient remained hospitalized, the number of days spent in the cohorting bay (regardless of whether the patient was eventually diagnosed with TB or not), and the number and proximity to TB index cases. There was no difference in the performance of each of these 3 measurements of nosocomial TB exposure for the prediction of one-year TB incidence.

Conclusion

Substantial TB exposure, particularly among HIV-infected patients, occurs in nosocomial settings despite implementation of cohorting measures. Nosocomial TB exposure is strongly associated with one-year TB incidence and TB-related mortality. Further studies are needed to identify strategies to reduce such exposure among susceptible patients.

Emergency department presentation of children with tuberculosis

OBJECTIVES

The objectives were to describe emergency department (ED) presentations of children with tuberculosis (TB) disease and assess the utility in children of TB screening tools developed for adults.

METHODS

Children at most 18 years old with confirmed or probable TB seen at the Children's TB Clinic from 2005 to 2009 who were initially evaluated in the ED for symptoms compatible with TB in the preceding month were included. TB was classified as microbiologically confirmed disease or probable TB disease, as defined by the World Health Organization.

RESULTS

Sixty children (29 with confirmed TB and 31 with probable TB) were identified after presentation to the ED, representing 35% of all children diagnosed with TB at the two hospitals during this interval. Eighty-eight percent were previously healthy. Fifty-five percent were Hispanic, 30% were black or African American, 12% were Asian, and 3% were white. Forty-four (73%) had intrathoracic disease (37 pulmonary parenchymal or pleural disease, four miliary disease, two endobronchial, one pericarditis). Sixteen (27%) had extrathoracic disease (eight meningitis, five cervical lymphadenopathy, two gastrointestinal, one interstitial keratitis), 11 of whom also had abnormal chest radiographs, including all eight children with TB meningitis. Most (76.7%) were diagnosed at the time of their first ED visit or during their first hospital admission, 12% after their second ED visit, 10% after their third ED visit, and one patient after six ED visits to various facilities. In 33 case (55%), the diagnosis was suspected in the ED because of epidemiologic risk factors (15), radiographic evaluation (11), or symptoms (7). Hemoptysis (12%) and night sweats (10%) were uncommon. Neither cavitary lesions (seen in two children) nor apical lesions (seen in 42%) predominated. The five screening tools validated for adults with pulmonary disease were 77% to 98% sensitive in identifying children with intrathoracic TB and 50% to 100% sensitive for extrathoracic TB.

CONCLUSIONS

The point of entry to health care for many children with TB is the ED. The more protean manifestations of TB in children can decrease the utility of screening tools developed to identify adults with TB. While TB in adults often is a microbiologic diagnosis, childhood TB often is an epidemiologic diagnosis. Therefore, questioning caregivers about TB risk factors in the family may identify a higher percentage of children with possible TB.

Communicable respiratory threats in the ED: tuberculosis, influenza, SARS, and other aerosolized infections

Respiratory infections are the most common communicable infectious diseases. EDs are the front line for patients with respiratory infections because of their acute nature and because the ED is the principal site of health care for those at highest risk. These diseases include influenza, tuberculosis, and measles, together accounting for 25% of infectious causes of death worldwide. These are emerging and biothreat agents that follow the same route of transmission, such as pneumonic plague. We discuss epidemiology, pathogenesis, diagnosis, and treatment of each agent. Emphasis is on the ED's role as a public health prevention arena, with attention to education and disease prevention, early identification of disease in patients at risk, and reduction of illnesses.

The emergency department presentation of patients with active pulmonary tuberculosis

OBJECTIVE

To determine the clinical presentation of emergency department (ED) patients with active pulmonary tuberculosis (TB).

METHODS

This was a retrospective medical record review of adult patients, identified through infection control records, diagnosed as having active pulmonary TB by sputum culture over a 30-month period at an urban teaching hospital. The ED visits by these patients from one year before to one year after the initial positive sputum culture were categorized as contagious or noncontagious, using defined clinical and radiographic criteria. The medical records of patients with contagious visits to the ED were reviewed to determine chief complaint, presence of TB risk factors and symptoms, and physical examination and chest radiograph findings.

RESULTS

During the study period, 44 patients with active pulmonary TB made 66 contagious ED visits. Multiple contagious ED visits were made by 12 patients (27%; 95% CI = 15% to 43%). Chief complaints were pulmonary 33% (95% CI = 22% to 46%), medical but nonpulmonary 41% (95% CI = 29% to 54%), infectious but nonpulmonary 14% (95% CI = 6% to 24%), and traumatic/orthopedic 12% (95% CI = 5% to 22%). At least one TB risk factor was identified in 57 (86%; 95% CI% = 76 to 94%) patient visits and at least one TB symptom in 51 (77%; 95% CI = 65% to 87%) patient visits. Cough was present during only 64% (95% CI = 51% to 75%) of the patient visits and hemoptysis during 8% (95% CI = 3% to 17%). Risk factors and symptoms that, if present, were likely to be detected at triage were foreign birth, homelessness, HIV positivity, hemoptysis, and chest pain.

CONCLUSIONS

Patients with active pulmonary TB may have multiple ED visits, and often have nonpulmonary complaints. Tuberculosis risk factors and symptoms are usually present in these patients but often missed at ED triage. The diversity of clinical presentations among ED patients with pulmonary TB will likely make it difficult to develop and implement high-yield triage screening criteria.