Before I start, my son is OK and back to normal and I'm just looking for a few answers. My son went in for a routine ear tube surgery. If the adenoids were large those were to be removed at the same time. The surgery went well and the ENT came out and said all was OK and we'd see our 4 year old son in about 15 or 20 minutes. He had tubes placed and adenoids removed. Over an hour went by and finally the ENT and Anesthesiologist came out and took us to a back office. They said our son was stable but we may need to transfer him to a hospital with a pediatric ICU. They said that upon removal of the breathing tube they found frothy pink fluid which means he aspirated. I asked if he threw up something and they said no, that they had checked stomach contents before the procedure. They said my son had pulmonary edema (doctors were clearly rattled while describing)and they did not see any gagging or any indication there was a problem. The Anesthesiologist said that she had been practicing for 30 years and had never seen this rare occurrence...no gagging, no choking and no indication there was a problem. His oxygen levels dropped but I don't know how low. To calm my waking son, the administered narcotics and gave a large dose of diuretic. On a subsequent call, the doctor described "negative pressure pulmonary edema" likely caused by a partial blockage of the tube. Is this a rare incident? Does faulty equipment cause this type problem? Why wouldn't the equipment alert the doctor? My son was never transferred to the hospital. He recovered fully and has no apparent issues. Like I say, everyone at this surgery center rattled like I have never seen. There were 3 other doctors in the building and 5 nursed who frequently stopped by to check on him. What went wrong and how serious was this for my son?
Negative pressure pulmonary edema (NPPE) is a relatively rare complication of anesthesia and is usually caused by trying to breath against a closed breathing circuit. Imagine you're trying to breathe through a tube (or hose or straw) and somebody blocks the other end but you still try to take a deep breath in. What that does is to create negative pressure that makes bubbles (froth) out of your lung fluids. It's hard to explain but if you can get a hold of a 20cc syringe, you can do an experiment to demonstrate it. Fill the syringe with 10cc of water and get rid of all the air. Then hold your finger over the end and pull back on the plunger. You will see bubbles form in the water. This is the same effect. The usual way it happens in anesthesia is the patient bites down on the endotracheal tube and occludes it and then attempts to breathe. We try to prevent it by placing a bite block so they can't bite down. This is different from aspiration where stomach contents get into the lungs. That is much worse. NPPE is treated conservatively by observation, and oxygen (which is what I'm sure they did). Diuretics are not usually indicated but it is not wrong to give them. This is not caused by faulty equipment and does not have any long term sequelae.
I hope this helps,
Ronald Levy, MD
Professor of Anesthesiology