This cross-sectional study followed the SQUIRE guidelines and was approved by our hospital ethical committee (C.I. EST: 55/20). Patients’ informed consent was waived.
Our health area coped with the highest COVID-19 burden (26.4%) at the Region of Murcia. There were 233 confirmed SARS-CoV-2 infections, 4004 accumulated possible cases and 4687 contacts by April 17th, 2020, when recruitment ended. In the same period, 152 COVID-19 patients were hospitalized, which was also the highest number in all health areas (23.4%).
Considering the usual number of patients seen in our ED before the pandemic start (e.g. 20-26 February: 1657 patients) and a ratio of respiratory/non-respiratory patients close to 1 (0.94, 206/218, 20-26 March) during the first epidemic week, we expected 118 [(1657/2)/7] or more daily respiratory emergencies during the epidemic wave. The average waiting time for patients with suspected respiratory infection at the ED during the epidemic wave was 5:48h. Despite the ED having established separated ways for respiratory and non-respiratory patients, COVID-19 infection risk would presumably increase if health care was provided through the usual indoors overcrowded ED environment with extended waiting-times . Accordingly, we designed a straightforward specific radiology algorithm trying to keep the vast majority of possible pneumonia (ppCOVID-19) patients out of the ED, through an individualised short-time service while being highly effective for triaging need for admission.
2.1 pcHRRS characteristics
The pcHRRS provided thorax x-rays and oximetry, making unnecessary a direct GP-to-patient contact. To be useful, the pcHRRS had to be 1) relevant: by deciding next steps; 2) accessible: available in less than 24 hours for any home-confined patient; 3) swift: less than 15 minutes RD workflow without waiting time on an only-one-patient appointment and expedited electronic report for the GP or the ED; and 4) safe: by reducing risks of a) Staff infections: radiographers and nurses in charge of the oximetry and patient’s navigation avoided close contacts with the available personal protective equipment; b) Patients infections: they knew in advance how to reach the radiology room limiting interactions with other patients; barrier and hygiene resources were always available; and c) Wrong communication with the ED: COVID-19 ED physicians were fully aware of patient’s management through the pcHRRS .
2.2. pcHRRS resources (fig.1, Supplementary fig.1)
- General practitioners.Suspected or confirmed COVID-19 cases were interviewed by telephone every day. GPs had to rule out ppCOVID-19 if fever remained more than 6-7 days or persistent respiratory symptoms or worsening of respiratory or general condition at any time (especially dyspnoea). Those patients were appointed to the pcHRRS.
- Specific electronic agenda. GPs could schedule thorax x-rays into the radiological information system from 9:00 a.m. to 9:00 p.m., every 15 minutes Monday to Sunday, and every 30 minutes on weekends and holidays.
- COVID-19 radiology room. Short street access room with a robotized x-ray digital 3D tomosynthesis (3DDT) and immediate PACS archiving, limiting any patient-to-patient and patient-to-staff interactions.
- Radiology Department workflow
a) Administrative staff. As soon a patient was appointed, a Radiology secretary phoned encouraging him to attend the appointment and giving instructions for a safe access to the radiology room (Supplementary fig.2). A radiology resident played that role on weekends and holidays.
b) Reception. Upon arrival, the patient warned the reception staff that he was coming through the pcHRRS and was provided with a surgical mask. Relatives generally waited in the street to avoid person-to-person interactions. The reception staff checked that patients knew how to reach the radiology room, preventing random navigation through other areas.
c) Radiology Department radiographers and nurses. When arriving to the radiology room, the patient proceeded immediately when the door was open. They were instructed to clean their hands with hydro-alcoholic solution, alcohol or to put gloves on, depending on daily resources. Within the room they received remote instructions from the radiographer so as to do the posteroanterior and lateral thorax x-ray radiographs, or a lateral radiograph and 3DDT. Then, the nurse performed oximetry and informed the radiology resident. Once the radiologists assessed the x-rays and decided the next step, the nurse informed the patient and, when needed, went with him to the ED admission point, preventing him from accidentally leaving the pcHRRS or random navigations, and avoiding delays and x-rays repetitions. When occasional delays made an arriving patient to wait outside the room, the patient within stayed in the changing room while the radiographer cleaned every contacted element. Once the decision was made, the technical staff cleaned the changing room and started again.
d) Radiologists. A resident and a staff radiologist worked close to the COVID-19 room, allowing a fast and direct communication always maintaining a safe distance with radiographers and nurses, and between themselves. The Radiology resident, who was the only additional pcHRRS personnel resource, 1) assessed thorax x-rays and was allowed to send the patient to the ED when sure about signs of pneumonia; abnormal x-ray with findings different from pneumonia where handled as usual (Supplementary fig.3); 2) drafted structured reports to be eventually validated by the radiologist; he used standardized radiology information according to scientific recommendations , also including oximetry results and the patient’s final destination (Supplementary fig.4); 3) phoned the ED COVID-19 physicians warning about abnormal x-rays; 4) recorded and followed up every case; 5) recorded every pcHRRS incident; and 6) played the administrative role on weekends and holidays, being the reason for the 30 minutes time slots on those days. The radiologist supervising the pcHRRS on weekdays was one of our regular on-duty emergency radiologists, and the on-call radiologist on weekends and holidays. They guaranteed a correct workflow, supervised the radiology resident, and validated radiology reports in non-conclusive and normal cases, and whenever requested by the resident.
5. Emergency Department. A COVID-19 physician evaluated every pcHRRS patient with radiological findings of pneumonia. The workflow was streamlined since the patient didn’t need a triage and had reported x-rays and oximetry.
6. Crisis committee. The Head of the RD, the Primary Care Network Director and the Medical Director of our health area, and one of the emergency radiologists met every day to know the number of involved patients, clinical results and incidents, so as to make changes on the fly. When required, the RD Supervisor and the Administrative Coordinator, and the ED COVID-19 Medical Coordinator attended the initial meetings.
For our purposes, all consecutive pcHRRS and the ED patients with respiratory infection symptoms were retrospectively studied from 5 days before the pcHRRS started. All pcHRRS patients underwent conventional thorax x-rays with posteroanterior and lateral views. A systematic assessment by 3DDT and oximetry were implemented later in the pcHRRS.
3. Statistical analysis
Patients were stratified in: Group 1 (G1: pcHRRS; normal x-rays; returning home); Group 2 (G2: pcHRRS; x-rays pneumonia findings; referred to the ED); and Group 3 (G3: ED; respiratory infection symptoms according to the ED physician). For G1, the process length was the period between the pcHRRS appointment time and the radiology report validation time; if any patient arrive at hospital before the appointment time, the process length was considered the period between the exam acquisition and the radiology report validation time; for G2 and G3, it went from the arrival time to the ED to the clinical report signature time. Any G1 patient deciding to seek medical advice at the ED after leaving the pcHRRS was included in G3. Patients leaving or requesting voluntary medical discharge were included in the number of patients attended, but excluded from the time analysis, as this variable was lacking.
Patients’ inflow was represented by daily absolute and relative frequencies, and the total accumulated frequency for all groups, and the daily ratio of hospitalized patients for groups 2 and 3.
Komogorov-Smirnov test was used to assess the normal distribution of the quantitative variables. The Kruskal-Wallis, Mann Withney U and Chi2 tests were applied when appropriate. Qualitative variables are shown as absolute and relative frequency. Quantitative variables as mean ± standard deviation, median and interquartile range in square brackets or 95% confidence interval (95%CI), as appropriate Statistically significant differences were assumed when P <0.05. The analysis was performed with the IBM Statistics SPSS 20 software. Precise p values could not be extracted for the non-parametric tests using SPSS. For graphs, we also used the Excel Microsoft Office 365 software.