COPD vs. CHF Exacerbation (Chronic obstructive pulmonary disease vs. congestive heart failure)

Author: V. Dimov, M.D., Assistant Professor, University of Chicago
Reviewer: S. Randhawa, M.D.

An 84-year-old Caucasian female (CF) with a past medical history (PMH) of chronic obstructive pulmonary disease (COPD), rheumatoid arthritis (RA), congestive heart failure (CHF), hypertension (HTN), coronary artery disease status post Coronary Artery Bypass Grafting (CAD S/P CABG), atrial fibrillation (Afib) on Coumadin (warfarin) was admitted to the hospital 1 week ago with a COPD exacerbation which gradually improved. She was transferred to a transitional care facility for rehabilitation.

The resident on call is paged because the patient is severely short of breath (SOB) and tachypneic this afternoon.

What is the first step?

See and examine the patient right away.

Physical examination

A thin lady, who is visibly SOB, using accessory muscles.
Tachypneic at 34/min.
Tachycardic at 100 bpm, regular.
SpO2 85% on her baseline home O2 of 2L/min.
Chest: (B) decreased air entry and crackles.
Legs: no edema

What is the most likely diagnosis?

COPD exacerbation or CHF?
Pulmonary embolism (PE)?
Myocardial infarction (MI)?

What diagnostic tests and/or treatment would you suggest at this point?

Give furosemide (Lasix) 20 or 40 mg IV x 1.
Obtain ECG, cardiac enzymes x 2 q 8 hrs, first set now, BNPep, CXR and arterial blood gas (ABG).
Give some extra breathing treatments and transfer the patient to telemetry.
Also give aspirin (ASA) 325 mg po x 1 - this would provide the largest decrease in mortality if she has an acute myocardial infarction (AMI).

What happened?

Laboratory results (click to enlarge the image).

The ABG showed respiratory and metabolic alkalosis, and hypoxemia.
Is it PE?
Her INR is 2.09.
Cardiac enzymes x 1 are negative

The CXR showed bilateral pulmonary edema, more on the right side.

It looks like CHF but why is it more on the right side? It depends on the position of the patient. If she lies more on her right side, the congestion may be more predominant on the dependent side.

Is it pneumonia?
Less likely.
WBC elevation may be due to the steroids given for COPD exacerbation.

BNP is higher 1300.

The patient is breathing much more easily after the Lasix, she diuresed 500 ml (cc), and says that she feels at baseline.

Final diagnosis

CHF exacerbation.

Reason: noncompliance with diet, she was drinking a lot of fluids in the less controlled environment of the rehabilitation unit. Cardiac ischemia was ruled out.

What happened?

The patient's condition steadily improved and she was discharged home with follow-up with her PCP.

What did we learn from this case?

Always think about the common causes of SOB - CHF, COPD, AMI, PE. Take SOB complaint seriously and initiate the work-up and the presumptive treatment immediately.

Stay at bedside and reevaluate the result of the given treatment. This will help to avoid the dreaded "Code blue" announcement on the overhead system.

What are the most common causes of CHF admissions?

At least one identifiable precipitating factor was found in 61.3% in a study of 48,000 patients. In order of frequency, they were:

- Pneumonia or respiratory processes at 15.3%.
- Ischemia or acute coronary syndromes at 14.7%.
- Arrhythmia at 13.5%.
- Uncontrolled hypertension at 10.7%.
- Nonadherence to medications at 8.9%.
- Worsening renal function at 6.8%.
- Nonadherence to diet at 5.2%.

Related Reading

Dyspneic. DB’s Medical Rants.
Chronic Obstructive Pulmonary Disease (COPD).
Desperate to Cry, Desperate Not To. NYTimes.
I'm So Busy. The Happy Hospitalist, 05/2008.
ABG data not useful in the assessment of suspected PE - Am J Resp Critical Care Medicine, 2000
Heart Failure - JAMA Patient Page (PDF), 2011.

Published: 03/21/2004
Updated: 02/03/2011


  1. blood pression?

  2. M. Valendo, RN4/29/2010 9:12 PM

    Hi Dr. Dimov -

    Cases like this are sometimes difficult to manage in the acute stage. Sometimes you can't tell just by listening to the patient, and then sometimes you get the patient who has both CHF and COPD. I agree that a timely chest x-ray is needed. If you can get a good read in a timely manner it really helps point you in the right direction.

    The fact that this patient voided over 500ml and then began to feel better was a big hint that it was CHF. Sometimes it's not so easy.

  3. BNP is very helpful in many of these cases - it was revealing in this case too.

  4. Respiratory therapists are always called to give these patients treatments and in about 5 minutes we can (most of the time) tell whether it is CHF or COPD exacerbation. Always ask your RT how the patient responded to the albuterol neb/MDI. They can be a great resource. Crackles was another give away, as was the CXR. I'm sure the cost. angles were blunted?

  5. that abg doesn't show respiratory acidosis, it looks like a mixed acidbase picture. Chronic COPD causing a respiratory acidosis buffered overtime by the metabolic alkalosis (which doesn't happen acutely but over time) that theory sounds more plausible. The ph is slightly alkalotic and it seems as if the primary disturbance is the metabolic alkalosis.