Treatment guided by monitoring acute dyspnoeic adult patients with serial cardiopulmonary point-of-care ultrasound: a randomised trial

Background: Serial point-of-care ultrasound (PoCUS) has the potential for improving acute patient care through modifying treatment to the dynamic ultrasound findings. The objective was to investigate if treatment guided by serial PoCUS of the heart and the lungs in patients admitted to an emergency department (ED) with acute dyspnoea could reduce the severity of dyspnoea compared to usual care.

Methods: The study was a randomised, controlled, blinded-outcome trial in one ED in Denmark between Oct 9, 2019, to May 26, 2021, with a follow-up period of 30 days. In a convenience sample, patients  18 years admitted with a primary complaint of dyspnoea and no trauma were included and allocated 1:1 to a serial ultrasound and control group. Patients in both groups received standard care within one hour from arrival, including a single cardiopulmonary PoCUS. In the serial ultrasound group, additional two extra PoCUS was performed with two hours interval. The primary outcome was a reduction of dyspnoea on a verbal dyspnoea scale (VDS) from 0-10, where 10 was worst, registered at inclusion and after two, four, and five hours. Outcome assessors were blinded, whereas the treating physician and patients were not. The secondary outcomes in both groups were length of stay, 7- and 30-days mortality, number of readmissions, and the proportion of patients with a correct presumptive diagnosis in agreement with a final audit diagnosis. The sample size was calculated based on the primary outcome. The primary outcome was analysed with a mixed-effect model.

Results: We included 102 patients in the serial ultrasound group and 104 in the control group. Median age was 76, sex was even distributed, many were previous smokers, and had chronic obstructive pulmonary disease or arterial hypertension as the most common comorbidities. The mean difference in VDS between patients in the serial ultrasound and the control group was -1·09 (95% CI -1·51 to -0·66) and -1·66 (95% CI -2·09 to -1·23) after four and five hours, respectively. The treatment in the two groups differed, with a larger proportion of patients receiving diuretics in the serial ultrasound group. No differences were observed between the two groups regarding the secondary outcomes. No adverse events were present.

Discussion and conclusion: Serial PoCUS-guided treatment can, together with standard care, reduce the severity of dyspnoea compared to standard care alone because it gives the ED physician the possibility to tailor the treatment according to ultrasound findings. PoCUS could therefore be considered for routine use to aid the physician in stabilising the patients and thereby handling crowding and flow.

Trial registration number: ClinicalTrial.gov, NCT04091334.

Funding: Department of Emergency Medicine, Slagelse Hospital; Naestved, Slagelse, and Ringsted Hospitals’ Research Fund; Research Fund of Region Zealand and Region of Southern Denmark; and the University of Southern Denmark.

Ethical approval and informed consent: Approved by the Regional Committee on Health Research Ethics for Region Zealand, Denmark (SJ-744). The participants gave informed consent to participate in the study.