E is the correct answer. Why?

Explanation

The Ottawa Heart Failure Risk Scale is a validated clinical risk stratification tool designed to identify ED patients with acute decompensated heart failure (ADHF) who have a high risk of serious adverse events, which include death, myocardial infarction, and need for intubation or ICU admission. Using a series of binary questions, it combines features obtained from clinical history, examination, and diagnostic investigations to predict the risk of such events in patients presenting to the ED with dyspnea due to suspected heart failure. However, there are caveats to its use, including a variety of exclusion criteria and the fact that it is intended to be applied after initiating treatment for heart failure in the ED. 

The exclusion criteria for use of the Ottawa Heart Failure Risk Scale are the following: resting SpO2 < 85% on room air or normal home oxygen, HR > 120 bpm on arrival, systolic BP < 85 mm Hg on arrival, ischemic chest pain requiring nitrates, ST segment elevation on ECG, expected death within weeks from chronic illness, nursing home or chronic care facility residence, the use of chronic hemodialysis, and confusion, disorientation, or dementia. If a patient does not meet any of these criteria and has responded to treatment (such as IV diuretics or noninvasive positive pressure ventilation) in the ED, the risk scale can be applied. The scale ranges from 0–15 points, with risk strata of low, medium, high, or very high corresponding to scores of 0, 1–2, 3–4, and 5–15, respectively, though patients in the very high risk stratum have further increased risk of serious adverse events as their score increases. 

The predicted risk estimated by the application of the Ottawa Heart Failure Risk Scale can be used to aid in decisions regarding the disposition of patients with heart failure. The developers of the scale suggest patients in the low-risk (0 points) category be considered for discharge from the ED, while those in the high- (3–4 points) and very-high-risk (> 5 points) categories are not safe for discharge and should be admitted. Patients who are in the medium-risk (1–2 points) category can be considered for either discharge or admission depending upon patient factors such as access to follow-up and patient preferences. This risk scale was studied and validated in EDs located only in Canada, where practices regarding the disposition of patients with ADHF vary significantly from those in the United States. Given this, it is not recommended to rely purely on this risk tool or others that are available to determine the disposition of patients. Decisions should be made based on the entirety of the clinical context.