A way to improve or resolve a condition or diagnosis. This might include resolving the underlying cause or treating the signs of disease (symptomatic treatment).

Cost: $100 to $500

These cost ranges are approximate and may vary from region to region.
Additional charges may also apply.

YOUR VET MAY Recommend

Abdominal Lavage or Flushing

Cost: $100 to $500

These cost ranges are approximate and may vary from region to region.
Additional charges may also apply.


In a normal healthy horse, there is a small amount (about 50cc) of clear, sterile pale yellow peritoneal fluid that lubricates the very large and complicated intestine, and other organs in the abdominal space.

Peritonitis is infection of this huge and complicated space, usually with bacteria. Infection results in the fluid increasing in volume, and turning cloudy, indicating a large increase in the number of infection fighting cells (inflammatory White Blood Cells) in the fluid.

Peritonitis can result from a variety of causes including wounds into the abdominal space and blood borne infections. It can also be a complication of colic surgery.

Vets use systemic antibiotics to fight this infection, however sometimes these are not enough. There is simply too much infectious material in the cavity and the resulting septic "stew" must be diluted, drained and flushed away. In this case, we perform an abdominal lavage.


In the standing horse, a large abdominal (or chest) sterile plastic drainage tube is placed into the abdomen. The horse is usually sedated for the procedure. The site, which is usually on the lowest, front part of the belly, is clipped and surgically prepared.

A local anesthetic numbs the skin at the selected site. A skin incision is made surgically and the abdominal wall is separated to allow the placement of the tube into the abdominal space. The abdominal wall is 3-6cm thick, depending upon the horse. Most chest drainage tubes come with a sharp poker that sits within them (a stylette), which is held within the tube during placement. This keeps it rigid and allows it to penetrate the wall. The stylette is removed once the tube is in place.

In most cases, the tube is sutured in place to maintain drainage and act as a portal for repeated flushing.

Excessive pus is initially drained out. Large quantities (10 liters on average) of sterile intravenous fluids are placed into the abdomen through the tube. They are allowed to sit in the abdomen for a short period of time before being drained. This may be repeated.

In many cases, the tube is left in place (often with a one-way valve known as a Heimlich Valve) allowing the procedure to be repeated later. The procedure may be repeated once or even twice daily until it is believed that the infection is under control or cleared.

my vet's role


A rare side effect is damage to organs or intestine during placement of the flushing tube.

Potentially, an infection could be carried into the space by poor technique or infected instruments or tube.


Abdominal drainage and lavage may not be needed in simple, mild cases that are responsive to systemic antibiotics.

your role

Is it working? Timeframe for effect.
In most cases, horses with severe peritonitis act very ill. They are depressed and off feed and have high heart rates and fever.

Within minutes to hours of aggressive removal of toxic by-products of inflammation and infection, horses seem to feel visibly better. That improvement should continue after the tube is removed.
Questions To Ask Your Vet:
  • Is this procedure really needed, or can the infection be managed through the use of antibiotics alone?
  • Is abdominal lavage (flushing) needed to fight this stubborn infection in my horse?

Author: Doug Thal DVM Dipl. ABVP