I just had major surgery, and was reminded of the process that involves anesthesia causing gas. To say nothing of the process that involves the worst food on the planet. (Hmmm – a connection there?)
I was told once that somehow the forcing of oxygen and gas into your lungs is more than the lungs can handle, and that it permeates the lungs, ends up in the body cavity, and reabsorbs to come out either through the stomach as burps, or the other end of the digestive tract as flatulence (not flagellants… ouch!).
I’m wondering about the connection between flatulence and the “About This Message Board” category you’ve posted in. Ziji, you might have better luck getting an answer if you post the inquiry in the General Questions forum.
If we take as a given that anasthesia causes flatulance, then I think that the simplest explanation would be muscle relaxation, not gas diffusion. Presumably, one of the Dopers with medical experience will come forward to correct one or both of us.
Unequivocally, this is not the mechanism for post-anesthesia flatulence (PAF). While gas under pressure can escape the lung (this is termed barotrauma) the result is a local gas pocket in the chest (termed pneumothorax-collapsed lung in lay terms). This does not happen as a “normal” result of anesthesia. And if it happened to you, you’d know it because lots of excited medical folks would be jumping around sticking tubes into your chest.
It is similarly unlikely that gas passed directly into your stomach during your procedure. During surgery, anesthesia is administered through a tube inserted directly into your trachea (windpipe). While the openings of the trachea and esophagus are close together and is is possible to insert the tracheal tube into the esophagus, physicians generally avoid this as it causes DEATH
My best gusses to explain your PAF are:
A slowdown of your intestines (ileus), commonly occuring post-operatively
Antibiotics. You may have been given some and not know it. They can alter the spectrum of bacteria present in your gut producing changes in digestion.
You just a farty guy (gal?). It took a period of post-operative self-reflection to realize this.
Normally, when a person has major surgery, he’s warned not to eat anything for several hours before the procedure. Depending on the type of surgery, the doctor might order “enemas til clear” to mechanically remove the contents of the intestines. After surgery, the patient’s not allowed anything to eat until his bowel sounds return (anesthesia and narcotic pain meds cause your digestive system to go on hold for a while). When bowel sounds do return, the patient is started on a clear liquid diet: Jell-O, water, broth, etc.
The bowels are working, but the patient doesn’t have much food in the intestinal tract until after he starts back on regular food. So, what comes out is mostly gas for a while. The bacteria in your intestestines are always producing gas.
Also, the doctors and nurses are constantly asking, “have you passed gas yet? Are you passing gas?” until the patient becomes fixated on the mysterious significance of gas. The medical staff is just trying to figure out if your intestines are working normally.
As choosybeggar pointed out, the introduction of air into the body through the esophagus or through the walls of your lungs is extremely undesireable. If your surgery involves laparoscopy, though, the doctor will inject gas into your abdominal cavity so he can visualize and reach your organs. After surgery, they squeeze out as much of this gas as they can, but some of it remains. It does not, however, work its way into your intestines to cause flatulence; it’s gradually absorbed into your tissues. It’s pretty painful, too, until it’s all absorbed.
Ziji, you might have better luck getting an answer if you post the inquiry in the General Questions forum.