13 February 2006

Rice Krispies

It's 7:30 AM, and I have just come on shift. The ED is empty and I am just sitting down with a cup of coffee and going through my mail. Nice to start off slow for once. But the nurses inform me that I have a "sick one, probably an allergic reaction." The story is that he woke up suddenly short of breath, eyes and throat swelling shut, with pain in the left upper chest area.

I head into the room to see the fellow, and the nurses were right. He is very sick indeed. The numbers look bad (HR 135, BP 95/60, SpO2 84%) but he looks worse. Obviously he is in distress, sweaty and working hard to breathe, splinting on the left, voice muffled in that "hot potato" tone that will set every ER doc's hair on end. The left eye is swollen shut, and his face looks a little puffy, but there's no redness, which would be expected with an allergy, and a quick peek in his throat shows no obvious swelling, though that can be deceptive. Lungs clear with good breath sounds bilaterally. Hmm.

Okay, let's get some basic things going: oxygen, IV access and fluid bolus, get respiratory therapy for some breathing treatments, call for a portable chest x-ray, ECG. This looks odd. It doesn't look like an allergy -- no wheezing, too much pain. Probably a PE (blood clot in lungs) but why is his face swollen? Has he occluded his superior vena cava? No, that's silly, SVC syndrome doesn't happen acutely. But his neck looks kind of swollen, doesn't it? Moreso than it did only five minutes ago. The circumference of his neck now exceeds that of his head, giving him a comical appearance not unlike that of the Mayor in Nightmare Before Christmas. Weird. I reach out to touch it and the skin crackles under my fingertips: Rice Krispies. Subcutaneous emphysema: like the popping of the air cells in fine bubble wrap, the tissues of the neck and (I now realize) the face and the chest have been infiltrated with air, and they crackle and snap under the pressure of my touch.

"Don't worry, sir," I reassure the patient, who is visibly freaked out by the stranges noises, "I know what this is and we can take care of it."

There's really only one place that air in the neck can come from -- the mediastinum, the potential space in the middle of the chest between the lungs. Typically, it comes from a punctured lung, though occasionally it may come from a ruptured esophagus. The patient is started on broad-spectrum antibiotics and undergoes a CT scan, which confirms the diagnosis:

Further images and some annotated images for our non-medical folks can be found here.

Other images showed a very small left anterior pneumothorax -- a ruptured lung -- which was the likely source of the air. Since I was working at our rural site, I arranged for transfer to the main hospital, where there is cardiothoracic surgery and pulmonary medicine. The patient looked much better with some IV fluids, oxygen, and pain medicine. While we awaited transfer, he continued to puff up more and more. It really was amazing: if you look at the CT scans, you can see free air all through the neck, chest, and back; his face continued to swell till both eyes were swollen shut. Each breath was like a stroke of the bellows, forcing more air into the tissues. I worried a little that there might be a tension pneumomediastinum, but his blood pressure remained stable. Given how small his pnemothorax was, we elected not to put in a chest tube.

At this point, the patient remains in ICU (day 3). He has had no decompression of any kind and is showing improvement. His espohagus was intact. As best we can figure, it was a spontaneous event, most likely due to underlying subclinical COPD. A rare and dramatic presentation -- only the second or third such one I have seen in eight years at this job.

Nope, this job is never dull.


  1. Excellent clinical vignette. Nice of you to provide the CT image as well.
    We don't see this in pediatrics...

  2. Wow. Your blog is always worth a visit.

  3. Very interesting stuff. I saw this unfold like an episode of ER, but with better clinical information being provided of course.

  4. this freaks me out!