Blog with interesting cases and/or problems related to anesthesia with discussion based on best evidence in the literature.

March 30, 2014

Severe Chest Pain after EGD and Colonoscopy

A 43 year old female patient arrived for same day surgery at the hospital for an EGD and Colonoscopy.  She worked as a nurse at a nearby hospital. My partner started the case and I relieved him near the end.  A propofol infusion was used to maintain deep sedation, while versed and fentanyl (2mg/100mcg) were given at the beginning.  The case lasted aproximately 40 minutes.  The patient emerged from anesthesia without incident and was taken to the recovery area.

About 10 minutes later I was called by the nurse.  The GI nurse reported that the patient was experiencing severe chest pain.  I ordered an EKG and went to see the patient. The patient appeared in severe distress, gripping her chest and moving about in the bed unable to get comfortable.  She described the pain as tight, and over the sternum directly in the middle of her chest.  She stated that the pain was constant.  Her vital signs were normal.

I quickly asked a few questions; how would you describe the pain? (gripping/tight), does it go anywhere else? (no), have you had this pain before? (no), Do you feel short of breath? (no). Have you ever had a heart attack or do you have heart disease? (no).  She did state that her mother had a heart attack when she was 49 years old, and her husband standing at her bedside related that he had a heart attack at age 42 (he was now 46).   This last piece of information was not clinically relevant, but important because he was becoming very anxious and this was being transmitted to her making her even more anxious.

The EKG showed that she had prominent Q waves in the anterior chest leads (V1 and V2).  This is consistent with an old MI in the anterior left ventricle. She also had a history of severe hyperlipidemia. Nevertheless, given her young age, no history of CAD, no obvious vital sign changes consistent with myocardial ischemia, or other evidence of acute ischemia, I felt that her pain was likely not cardiac in origin.  This was backed up by an EKG that did not demonstrate any changes in the ST segment. Of course, severe chest pain after an EGD/Colonoscopy can have other causes.  These can include esophageal rupture, aortic aneurysm rupture or exacerbation, intercostal muscle spasm, or acute esophageal spasm. Because the patient complained of severe chest tightness, a Chest X ray was ordered in an abundance of caution to rule out more sinister causes such as aneurysmal rupture or pneumomediastinum or pneumothorax.  At this point, with no obvious cause for the patients chest tightness that was obvious causing great distress (the CXR was normal), I suspected that she might have an acute esophageal spasm.

First, however, I want to discuss a quick guideline to ruling out a cardiac origin for chest pain in the post operative patient.  I find that this often results in consults to cardiologists, but in most cases this is unnecessary.  In 2010, the National Institute of clinical excellence (NICE) guidelines were published which can serve as  a helpful starting point for the anesthesiologist confronted with post operative chest pain. In particular, it can be helpful in patients who may have one or two risk factors for CAD such as this women (significant hyperlipidemia and strong family history).  The guidelines highlight that in many cases, a diagnosis of angina can be made clinically. According to the 2010 NICE guidelines, an exclusion of angina can be made if the pain does not fulfill any of the following three criteria:

  1. a constricting discomfort in the front of the chest, neck, shoulders, jaw, OR arms.
  2. Precipitated by physical exertion
  3. Relieved by rest, or NTG, in under FIVE minutes.
The NICE guidelines define Typical Angina as pain that fulfills all three criteria above, atypical angina that meets two of the three critieria and NON anginal chest pain fulfills one or none of the above criteria.  Our patient did have a constricting "like" discomfort in the front of her chest, and therefore met only one of the guidelines above.  She was resting in her bed, not in distress.  Based on this it is reasonable to consider other causes of her pain.  I ordered an EKG because of her history of uncontrolled hyperlipidemia and the fact that her husband was very anxious about her heart due to his own MI.   Therefore, I wanted to show him something physical of diagnostic value demonstrating no evidence of acute ischemic changes.   Furthermore, the above three criteria as listed are more fine tuned for outpatients who come reporting chest pain in an office setting rather than the post operative setting.  After surgery, the metabolic milieu may be more similar to the active state than the resting state although the patient is lying in bed.  Therefore, I believe using the revised cardiac risk index can help us in determining how we use the above three criteria.  These are listed below:

  1. high-risk surgery (vascular, intrathoracic or intraabdominal)
  2. history of CAD (h/o MI, positive stress test, ongoing Angina, use of nitrates, pathological Q waves on EKG).
  3. history of CHF (to include paroxysmal dyspnea)
  4. history of TIA or stroke
  5. Preoperative tx with insulin for glycemic control
  6. preoperative creatinine of > 2.0 mg/dL
assign one point for each: Our patient had 0 or maybe 1 point if you count her pathologic Q waves.
Class I=0 points and risk of major cardiac event (i.e. MI or significant ischemia) is 0.4%.
Class II=1  point-risk 0.9%
Class III=2 points-risk 6.6%
Class IV=3 or more points-risk 11%

Furthermore, there is evidence to suggest that there are indeed two groups of patients at highest risk for post operative MI:  Those with clinically diagnosed CAD, and those with documented severe peripheral vascular disease.  This patient had neither.

After getting a clear description of the pain, its onset, and nature, and determining the patient's overall risk status, a quick physical exam can actually be helpful.  A quick listen to the heart and lungs to rule out rales (indicating cardiogenic shock and pulmonary edema) and an S3 gallop can push you in another direction if they are present.  You can also ensure that you do not auscultate friction rubs or new onset murmurs i.e. an aortic regurge murmur that would indicate concern for aortic dissection.

At this point, a decision as to whether to order cardiac enzymes and if so, which ones must be made.  It is probably reasonable to order these in a patient who complains of chest pain and has significant risk factors (i.e. documented CAD, or 3 or more points on the RCRI) regardless of what the EKG looks like as up to 6% of patients with a normal EKG are ultimately diagnosed with MI.  If it seems prudent to order blood work, understand that patients with AKI or chronic kidney disease may have elevated troponins.  Furthermore, myocarditis, pericarditis, tacharrythmias, sepsis, and PE can all result in elevation of these enzymes.  In addition, a careful history is important, as these enzymes can remain elevated for 5 to 14 days (as opposed to CK-MB which goes back to normal in 2-3 days).

Diffuse Esophageal spasm in the perioperative period is not common.  There is little in the anesthesia literature on this entity.  However, in the surgical literature, a variety of different types of spasms with a variety of etiologies is described.  The above patient, if indeed this was esophageal spasm, likely had hypertensive spasm.  This simply means that there is not a concomitant motility disorder, but rather, the contractile force of the normal peristaltic motion is extremely high.  Effective treatments can include NTG (similar dose to treat myocardia ischemia, nifedipine, and isosorbid). I suspected that this patient had an acute esophageal spasm following her EGD, and therefore did not push to continue her workup after the EKG (even though it contained Q waves in the anterior leads). 

In the end, the patient received some morphine (not my order); and felt better.  I advised her to follow up with her PCP to begin therapy for her hyperlipidemia and discuss her risk factors for CAD.

While the drama surrounding the bold diagnosis that saves a patient's life is exciting, often times, being a great physician can be the ability to avoid unnecessary tests; some of which place the patient at greater risk.  A good understanding of pre test probability will the anesthesia provider in the post operative setting filter those patients who need more attention from those where less is definitely MORE.

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