Flatulence or Passing Gas After Surgery

Why Flatulence (Farting) After a Surgical Procedure Matters

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Pain or cramps in stomach
Passing Gas Can Relieve Stomach Discomfort. MarsBars/Getty Images

It is a strange fact that doctors and nurses may seem very concerned about your ability to “pass gas” after surgery. It is more than reasonable to wonder why there is such an unusual amount of interest in what is typically a pretty personal part of day-to-day life. Believe it or not, there is a good answer for all of the concern about your ability to release gas after having anesthesia

When you are recovering in the post-anesthesia care unit (PACU), you may be told to notify your nurse if you pass gas.

In the pediatric setting, a child may be told that the nurse would like to know if they “toot” or “fart”, which may cause some giggles or shyness.  

Why all of this focus on passing gas? It's rather simple really, it means you aren't developing a postoperative ileus.


After surgery, or more specifically, after the medications that are given during surgery, it is possible that a complication called a postoperative ileus (POI) may develop. This is a delay in gastric motility or the movements that push food through the gastrointestinal tract, and it is common after surgery. The severity can range from barely noticeable to a serious complication that requires significant medical treatment.  

In the simplest terms, a postoperative ileus means that it takes your intestines longer to wake up from anesthesia than the rest of you.  The ability to pass gas is a clear sign that your gastrointestinal tract is waking up and that POI is resolving, if present.

This is why nurses and doctors care about whether or not you pass gas in the hours after surgery. It is a sign that your digestive organs are returning to their normal state.

For some surgeries, the patient performs a bowel preparation prior to the procedure, which cleans the stool from the intestines.

 For these patients, it may be several days before they have stool, so passing gas is one of the earliest signs of their intestines waking up.

In the case of outpatient surgery, passing gas may be required before you are able to go home. The staff doesn’t want to send you home with a potentially serious complication, so don’t even think about being bashful, let them know if you have successfully passed gas.


Researchers do not agree on why postoperative ileus happens. One theory is that the sympathetic nervous system, which normally decreases the amount of movement done by the intestines, temporarily has greater control over the intestines than the parasympathetic nervous system, which increases the movement of the intestines.  

Another theory suggests that POI is caused during abdominal procedures by manipulating the intestines during surgery, such as moving them out of the way to reach other body structures or performing surgery directly on them. This starts a cascade effect when the white blood cells in the intestine are stimulated by the surgical activity and trigger other types of cells to move to the area. Other theories point to electrolyte imbalances and the use of opioids for pain control.


For most patients, the delay in gastric motility is brief, but for others, the complication requires a longer hospital stay than intended. For those patients, the symptoms of an ileus may be much more severe.

  • Nausea
  • Bloating
  • Vomiting
  • Abdominal tenderness or pain
  • Passing gas/stool is delayed or not possible

Risk Factors

Patients who have surgery that requires manipulation of the intestines or surgery performed on the intestines are at higher risk of developing postoperative ileus. The severity of POI may also be increased in these patients. Patients receiving opioid medications for pain relief are also at a higher risk of developing POI, as are patients who already have issues with their intestines.


While preventing postoperative ileus may not entirely be possible, there are ways to minimize the risk.  Patients receiving epidural anesthesia rather than general anesthesia typically have a quicker recovery from this complication. Minimally invasive techniques also may decrease the duration of postoperative ileus when compared to the more traditional surgical techniques. Walking after surgery, when appropriate, may play a small role in helping reverse ROI. 

One of the simplest solutions, which is showing promise in research studies, may be to chew gum after surgery. Several recent studies showed a decrease in the duration of postoperative ileus in patients who chewed gum and there was some evidence that their hospital stay was shorter than non-gum chewers.

A Word From Verywell

It may not be normal for your to talk about flatulence in your day to day life, or you may be completely comfortable talking about toots and stinkers, but the day of your surgery is the day to set aside any qualms you may have about talking about your bodily functions.  Be honest, because the alternative may be postoperative ileus not being diagnosed in a timely fashion, which is not a good way to start your recovery.


Alavi, Karim. Caroll, James. Pathogenesis and Management of Postoperative Ileus. Clin Colon Rectal Surg. 2009 Feb; 22(1): 47–50. doi: 10.1055/s-0029-1202886.