Chest Pain – 2

CHEST PAIN —  Last time we discussed the pain of coronary artery disease (see posting Chest Pain – 1).  So if we ruled out the heart, it could be the lungs.  That’s also bad.

First, be sure of the chronology.  Is this a pain that has persisted continuously since onset, or one that comes & goes?  Let’s start with the latter, very briefly.

Very briefly.  Intermittent Chest Pain will either be angina or non-anginal [duh].  Rule out the former [see previous post “Chest Pain – 1”], and you’re left with either gastrointestinal or musculoskeletal conditions, or anxiety.  Lung diseases that cause chest pain don’t come & go.

Since intermittent GI & MSK conditions are benign, it’s not terrible to get it wrong.  If other GI symptoms predominate, offer an acid suppressor.  If the pain is provoked by ranges of motion, like reaching, stretching, or twisting the torso, go for analgesics.

Chest pain associated with hyperventilation may seem pleuritic, since it’s occurring during pronounced breathing.  Just be cautious about picking up on anxious affect and concluding the mood is causing chest pain, because it may be that the chest pain (of whatever etiology) is causing the anxiety.

Of course, the real treatment is time.  These conditions are self-limiting, especially once the patient hears it’s not their heart or lungs.

So on to Continuous Chest Pain, all through the day, every day since onset.  This discussion focuses on recent onset chest pain.  Continuous chest pain going on a long time is virtually unheard of.

Separate the differential by determining if the pain is “pleuritic” or non-pleuritic.  “Pleuritic” means accentuated by breathing or coughing; it calls to mind pulmonary disease, unless it’s also exacerbated by twisting, bending, or reaching, which would suggest musculoskeletal etiology.  See the Table for our differential diagnosis of Chest Pain.

DIFFERENTIAL DIAGNOSIS – CHEST PAIN

Pleuritic Chest Pain

Non-Pleuritic Chest Pain

Some patients with some of these conditions may look quite sick, but not necessarily.  Let’s assume the latter; those gasping for breath go to the E.D.

For patients describing chest pain that’s clearly pleuritic, aim for the lungs.  Especially if there’s a cough, but even if not. The pulmonary conditions listed above may not be common, but are serious enough to at least want to consider and rule out.

Seek clues:

**  Fever suggests lobar pneumonia, especially if there are focal rales (inspiratory crackles).  But a whole host of conditions causing pleural effusions or pericarditis can also generate fever, as can a pulmonary embolus.  Get a chest x-ray (CXR).

  • A normal CXR virtually rules out pneumonia as a cause of chest pain.  It also rules out most pleural effusions (as long as it’s a 2-view, including the lateral).
  • A normal CXR says nothing about pulmonary embolism (PE)!
  • An infiltrate plus fever suggests pneumonia, but is also compatible with pulmonary embolism.  More about pneumonia when we come to the differential of “Cough.”  More about PE’s in a few postings when we hit “Dyspnea.”

**  Unilaterally diminished breath sounds on lung auscultation, though uncommon, may identify pneumothorax or pleural effusion.  Get a CXR.  It’ll also R/O an unlikely mass.  A CXR isn’t sensitive for small effusions or small pneumothoraces (is that the plural? [no pun]).  For a small effusion, you’d need to order a special “cross-table lateral decubitus view.”  For a small pneumothorax, order the film “in full expiration.”  These maneuvers are rarely necessary; with such minimal pathology, you wouldn’t detect diminished breath sounds anyway.

**  Leaning Forward.  A patient who seeks to relieve discomfort by bending over forward probably has pericarditis (or pancreatitis, if pain is upper abdominal).  An auscultated friction rub is quite specific (high-pitched scratch or squeak in systole and/or diastole, loudest at the left sternal border).  The EKG makes an easy diagnosis — there’s S-T elevation just like an acute MI, but across the board in all leads.  An actual MI in all leads wouldn’t make it in.

**  Dyspnea.  Pleuritic chest pain plus dyspnea is a sure bet for lung disease.  The dyspnea may only occur during exertion — clarify this.  The converse, dyspnea at rest but not with exertion, will be psychological (unless we’re talking the orthopnea of heart failure, cardiopulmonary shortness of breath always exacerbates with increased demand).

  • Get a CXR for pleuritic chest pain plus dyspnea.  Also realize that it may be negative with a PE.  More about dyspnea & PE’s in a later posting.

**  Chest tenderness suggests a chest wall disorder, especially if it reproduces the patient’s pain.  This is usually benign, except in the case of a pathologic rib fracture, like from cancer metastases.  Suspect this if there’s very focal tenderness to percussion over bone.

  • Other findings of rib fractures include tenderness to rib cage compression [don’t compress too hard], or tenderness to punch percussion on a distant area of the rib, that transmits to the suspected site.
  • A CXR may miss the lesion; order a dedicated rib series.  Even this may not be sensitive, requiring a bone scan.  No need to rush, since metastatic cancer isn’t curable anyway.  While prescribing analgesia & waiting for symptoms to resolve on their own, obviating further work-up, order a serum alkaline phosphatase [a marker for bone disease if significantly elevated].

MORAL — You may well need to order a CXR for someone with new onset pleuritic chest pain.

When DON’T we need a film?  As mentioned above, for the many patients with obvious benign thoracic muscle strains:

  • Pain is exacerbated not only by breathing or coughing, but also by movement of the torso (reaching, bending, twisting, etc.).  It may just be one specific movement.  Lung disease doesn’t hurt like that.
  • Pain and/or tenderness-to-palpation are somewhat diffuse, not focal enough to suggest a rib fracture.
  • No dyspnea (distinguish bona fide dyspnea from “can’t exercise due to pain”).
  • Pain is not continuous all through the day.

The CXR will identify all the bad lung disorders in our Table, except for pleurisy (and pulmonary embolism: see below).  What is “pleurisy”?  Irritation of the pleura [surprise!].

If accompanied by pleural effusions, look up the textbook work-up (this blog doesn’t pretend to be a textbook).  “Pleurisy” without effusion is probably viral, self-limiting, and a diagnosis of exclusion.  It causes pleuritic pain that isn’t musculoskeletal [no tenderness, and not exacerbated by active range of motion of torso or shoulders], with perhaps a cough, and a normal CXR.

In other words, it’s a diagnosis without a gold standard, perhaps real, but always suspect.  It’s also different from pleuritis (frank inflammation), which can accompany collagen-vascular diseases, especially Lupus (SLE).  For a patient with pleuritic chest pain, no cough, and a normal CXR, inquire about similar past episodes.  Seek other symptoms of SLE, such as malar rash, other rashes, arthralgias, mouth ulcers, or patches of complete hair loss.  Order an ANA if in doubt.

The difference between pleurisy and chest wall pain is academic.

  • If there’s a cough, or pain occurs with coughing and breathing but not with twisting or stretching, and no tenderness to palpation, it’s “pleurisy.”
  • No cough, positive musculoskeletal findings, & especially if the duration too long to be a simple virus — call it “chest wall pain.”
  • Bottom line: CXR (if ordered) is normal, nothing alerts you to serious pathology, both conditions are benign and self-limiting.

Pulmonary embolus (PE) is the tricky diagnosis, which we’ll explore in more depth when we come to the work-up of “Dyspnea” (in a few more postings).  Both CXR & EKG are usually normal, as is physical exam.

But here, we’re discussing patients who present with “chest pain.”  I don’t worry about a PE if there’s no dyspnea on exertion.  One study found that among patients with pleuritic chest pain, respiratory rate <20, and no dyspnea, only 4% had a PE.  It’s not 0%, but still reassuring.   See Br J Haematol 2011;153:253-8.

Next time: Non-Pleuritic Chest Pain, to round out the discussion.

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s