The Cardiac Output in Heart Failure (COHF) study in Emergency medicine

Background: Acute pulmonary oedema (APO) is highly prevalent in the Emergency Department (ED), with significant morbidity and mortality rates, however, there is a poor evidence base to support the efficacy of common interventions, particularly loop diuretics such as frusemide (furosemide). Therefore, there is a need for rigorous investigation of the
impact of such interventions on key variables, such as cardiac output and patient outcomes.
Objective and design: This investigation assessed the impact of non-invasive ventilation (NIV) and diuretic therapy on cardiac output (CO) of all patients presenting to Liverpool Hospital ED, with signs and symptoms of APO, over a three-month period (n=75). This prospective observational study used haemodynamic data, derived from an ultrasonic cardiac
output monitor (USCOM), to elucidate the impact of these interventions on these patients. Additionally, the association of sociodemographic variables to patient outcomes were analysed, using the culturally and linguistically diverse (CALD) status of patients, in order to investigate the possible impact of CALD status on presentation, outcomes and interventions.
Method: Patient information, collected from the Cerner FirstNet® electronic medical record, was combined with cardiovascular measurements obtained using the USCOM 1A® device.
Using R Studio®, a bivariate analysis of the patient sample was conducted, using demographic variables including CALD status. The baseline haemodynamic variables of all patients were also compared on the basis of age, gender and triage vital sign observations. Additionally, outcomes-based and trend analysis of the impact of frusemide and NIV, as well as other common interventions was conducted.
Results: CALD patients were significantly older (p=0.0432) and had a significantly longer ED LOS (p=0.049). Older patients and those admitted to the respiratory ward had notably lower CO and CI. Patients who were administered frusemide had the lowest cardiac output (CO) prior to receiving treatment, however Neither frusemide nor NIV has a significant impact on CO.
Conclusion: Non-invasive, continuous haemodynamic monitoring is crucial in individualising and optimising the risk-stratification and management of APO and other patients with cardiorespiratory compromise. Further investigation of the significance of the