of Major Risks Associated with Roux en-Y Gastric Bypass
Gastric Bypass is a major operation that carries substantial risks.
In making the decision to have this procedure done, it is critically
important that patients understand the risks associated with the
operation. The benefit of weight loss surgery is to enable the patient
to have a tool to help with diet. Appropriate dietary intake with
exercise will greatly improve results of the weight loss procedure.
Alternatives to this procedure is dietary guidance with psychotherapy,
diet and medication, using appetite suppressants, and finally all
of these programs will require an increase in physical activity.
Glucose intolerance and frank diabetes mellitus
• Sleep apnea and obesity associated hypoventilation
• Serum lipid abnormalities
the time a decision is made to have the surgery, you will be asked
to sign a consent form stating you understand all the risks involved.
You are encouraged to ask questions at the time of your consult
regarding any or all risks involved. Please read carefully; discuss
these risks with your family, friends or other medical professionals.
The risks are as follows:
With any major surgery, bleeding can occur. If sufficient blood
volume is lost, a transfusion might be necessary. There is approximately
a 1 in 500,000 risk of contracting AIDS or hepatitis from blood
transfusion. Many patients desire to bank their own blood in anticipation
for the need of a transfusion. The risk is somewhat higher in revisional
operations than in first time cases. There also can be bleeding
from ulcers that can develop in the pouch following surgery.
The spleen is a very fragile organ that lies immediately adjacent
to the operative field. It is easily injured and if sufficiently
damaged it may need to be removed. It serves as a filter for the
blood, as well as an immune organ. Patients without spleens generally
do quite well, but have increased susceptibility to certain kinds
of infections throughout their lifetime.
After the gastric bypass operation, anemia is inevitable. The stomach
is required for the normal absorption of iron and vitamin B-12.
Because of this, it is absolutely essential patients undergoing
bariatric surgery have life-long medical follow-up. For patients
undergoing the gastric bypass operation, it is essential that they
take supplemental iron and vitamin B-12 shots. Generally, chewable
vitamins with iron are sufficient for the iron requirement and 1000
micrograms/day of vitamin B-12 are necessary. Most patients require
periodic injections of vitamin B-12 to supplement the oral intake.
These injections need to be administered every 1-3 months.
Any abdominal surgery has the risk of causing bowel obstructions
(intestinal obstructions). This can occur any time in the future
and it is caused by scar tissue formation inside the abdomen.
can form around the loops of the bowel, obstructing them. This results
in pain, nausea and vomiting. It is possible that additional hospitalization
or surgeries might be necessary.
Patients are at risk of developing a post-operative hernia. These
hernias can occur through the incision, or an internal hernia may
form. Patients may be at risk of developing an incisional hernia
if they undergo an open procedure. Laparoscopic and open patients
may develop an internal hernia with a bowel obstruction caused by
Unlike intestinal bypass operations, malabsorption with resulting
diarrhea is not a feature of the gastroplasty or gastric bypass
operation. However, there is an occasional patient who experiences
chronic diarrhea lasting a year or more after surgery.
This is associated with the gastric bypass operation and patients
will have abdominal pain, cramping, nausea, diarrhea, heart palpitations,
dizziness, loss of consciousness, etc., when sugars and carbohydrates
are ingested. Patients rapidly develop an aversion for these substances.
Symptoms can be quite bothersome in the first few months after surgery,
but generally are fairly minor after that time.
Any time the stomach is operated on, nausea will develop. Nausea
can be significant for several days after surgery and it has been
known to be present for several months after the operation. Vomiting
is a main component of banded gastroplasties and is experienced
by virtually all patients who have these operations. On the other
hand, vomiting is unusual in gastric bypass patients. Some vomiting
is experienced as new diets are tried the first several months after
surgery, but it is unusual after that period of time. There is an
occasional patient who has problems with vomiting beyond this period
An abscess is an infection inside the abdominal cavity. When this
occurs, additional operations are often required to drain the infection.
Because the abdominal wall fat tissue heals slowly, it tends to
become infected. These infections are self-limited and are easily
treated by opening up the skin incision and allowing the wound to
heal from the bottom up.
Because obese patients have limited respiratory movements, they
are susceptible to development of pneumonia immediately after abdominal
Obese patients have poor blood flow in their legs. When these patients
undergo surgery of any type, blood tends to pool in the legs and
clot. These clots can restrict the venous drainage from the leg
resulting in significant leg swelling. This can become severe and
could require treatment with chronic blood thinners.
When a blood clot from the leg breaks lose and travels to the lung,
it is called a pulmonary embolus. Like a deep venous thrombosis,
it is a risk of surgery of any type in the obese. Special precautions
are taken in the operation room to avoid the development of deep
venous thrombosis of pulmonary emboli. All patients are required
to stop estrogen replacement therapy one month before surgery and
to stay off of estrogen replacement for at least two months after
The process of being put to sleep and waking up can result in a
heart attack or stroke. Although this can happen, it is extremely
It has been reported that calcium absorption is limited after gastric
bypass surgery. This can result in bone loss or osteoporosis with
resultant fractures. We recommend supplemental calcium after gastric
bypass to avoid the development of osteoporosis.
The Roux en-Y Gastric Bypass operation is permanent. There is no
need to reverse it once weight loss is achieved. If for some reason
you desire reversal, it is important recognize that the stomach’s
function may not return to normal. Surgical manipulation of the
stomach induces permanent alterations eating habits.
Some patients will experience some thinning of the hair during the
first six months after surgery. This is due to lack of protein supplements
in their diet. This will usually reverse itself after 6 months.
Patients who smoke are a high risk for surgery. Complications associated
with smoking are: Pneumonia, poor wound healing, pulmonary embolism
and death. Patients are urged to discontinue smoking 3 months prior
The anastomosis is where the bowels are connected together during
the surgery. There is a risk that leakage of intestinal contents
at this location that can result in serious complications. The most
severe is infection and the inability to eat for many months.
There are ulcers that occur in the small intestine of in the pouch
following obesity surgery. They can cause pain and bleeding. Medications
or revisional surgery may be required if this complication occurs.
Your surgeon will discuss the incidence of this surgical risk with
you during your consultation visit.