Gastroparesis (cont.)
How is gastroparesis treated?
Treatment of gastroparesis includes diet, medication, and devices or
procedures that facilitate emptying of the stomach. The goals of treatment
include:
- To provide a diet containing foods that are more
easily emptied from the stomach.
- Controlling underlying conditions that may be
aggravating gastroparesis.
- Relieve symptoms of nausea, vomiting and
abdominal pain.
- Stimulate muscle activity in the stomach so that
food is properly ground and emptied from the stomach
- Maintaining adequate nutrition.
Diet
Emptying from the stomach is faster when there is less
food to empty, so smaller, more frequent portions of food are recommended. Soft
foods (or preferably liquid) that do not require grinding also are emptied more
easily. Moreover, in gastroparesis the emptying of liquids often is less
severely affected than the emptying of solids. Fat causes the release of hormones that slow down the
emptying of the stomach. Therefore, foods low in fat empty faster from the
stomach. In patients with severe gastroparesis, sometimes only liquid meals are
tolerated.
Controlling underlying conditions
High levels of glucose (sugar) in
blood tends to slow gastric emptying. Therefore it is important to lower blood
glucose levels in patients with diabetes to near normal levels with diets and
medications. Individuals with a deficiency of thyroid hormone
(hypothyroidism) should be treated with thyroid hormone. If bezoars are present, they should be
removed (usually endoscopically).
Relieving nausea, vomiting, and
abdominal pain
Drugs used to relieve nausea and vomiting in
gastroparesis include promotility drugs (see discussion that follows) such as
metoclopramide (Reglan) and domperidone, anti-nausea medications such as
prochlorperazine (Compazine) and promethazine (Phenergan), serotonin antagonists such as ondansetron (Zofran),
anticholinergic drugs such as a scopolamine patch (commonly used for treating
motion sickness), drugs used for treating nausea in cancer chemotherapy patients
such as aprepitant (Emend), and medical marijuana Marinol.
Drugs used to relieve abdominal pain in gastroparesis
include non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen
(Motrin) and naproxen (Aleve), low dose tricyclic antidepressants such as
amitriptyline (Elavil), drugs that block nerves that sense pain such as
gabapentin (Neurontin), and narcotics such as tramadol (Ultram) and Fentanyl.
Narcotic pain relievers as a group tend to cause constipation and slow emptying of the stomach, and, therefore, should be avoided
or used with caution among patients with gastroparesis.
Stimulating muscle
activity
Oral Drugs. There are four oral drugs that are used to stimulate
contractions of the stomach's muscles, referred to as pro-motility drugs. These
drugs are cisapride (Propulsid), domperidone, metoclopramide (Reglan), and
erythromycin. Cisapride is an effective drug for treating gastroparesis;
however, it was removed from the market because it can cause serious and
life-threatening irregular heart rhythms. Despite this fact, it can be obtained
for use through the pharmaceutical company that manufactures it (Janssen
Pharmaceuticals) under a strictly monitored protocol but only for patients with
severe gastroparesis unresponsive to all other measures. Domperidone has not
been released for use in the US; however, it can be obtained if approval is
obtained for its use from the US Food and Drug Administration. The fourth drug, erythromycin (E-Mycin, Ilosone, etc.), is a
commonly-used antibiotic. At doses
lower than those used to treat infections, erythromycin stimulates contractions
of the muscles of the stomach and small intestine and is useful for treating
gastroparesis.
It has been demonstrated that tegaserod
(Zelnorm), an oral drug used for treating constipation in irritable bowel
syndrome (IBS),
increases emptying from the stomach just as it does from the colon. However, in March of 2007, the FDA asked Novartis to suspend sales of tegaserod (Zelnorm) in the United
States because a retrospective analysis of data by Novartis from more than
18,000 patients showed a slight difference in the incidence of cardiovascular
events (heart attacks, strokes and angina) among patients on Zelnorm compared to
placebo. The data showed that cardiovascular events occurred in 13 out of 11,614
patients treated with Zelnorm (.11%), compared to one cardiovascular event in
7,031 (.01%) placebo-treated patients. However, it is unclear whether Zelnorm
actually causes heart attacks and strokes. Doctors and scientists will be
scrutinizing the data to determine the long term safety of Zelnorm.
Further
studies will be necessary to determine just how effective tegaserod is and how
it compares to the other medications that are available for treating
gastroparesis before its use can be recommended.
There are two important
guidelines in prescribing oral drugs for gastroparesis. First, the drugs must be
given at the right times, and second, the drugs must reach the small intestine
so that it can be absorbed into the body. Since the goal of treatment is to
stimulate muscular contractions during and immediately after a meal, drugs that
stimulate contractions should be given before meals.
Most drugs must be emptied
from the stomach so that they can be absorbed in the small intestine. The
majority of patients with gastroparesis have delayed emptying of solid food, and
pills and capsules, like solid food, do not empty well from the stomach. As
mentioned previously, many patients with gastroparesis have less of a problem
emptying liquids as compared with solid food. Therefore, liquid medications
usually are more effective than pills or capsules.
Intravenous drugs.
Occasionally, patients have such poor emptying of both liquid and solid food
from the stomach that only drugs given intravenously are effective. In such
patients, intravenous metoclopramide or erythromycin can be used. A third option
is octreotide (Sandostatin), a hormone-like drug that can be injected beneath
the skin. Like erythromycin, octreotide stimulates short bursts of strong
contractions of the muscles in the stomach and small intestine. Due to its
greater expense and the need for injection, octreotide is used only when other
medications fail.
Electrical pacing.
Electrical pacing of the stomach is a new method for treating severe
gastroparesis. Electrical pacing of the stomach is analogous to cardiac pacing for the treatment of an abnormally slow heartbeat
and involves the placement of a pacemaker. The pacemaker usually is placed
laparoscopically and does not require a large abdominal incision for entering
the abdomen. During placement, wire electrodes are attached to the muscle of the
stomach. The wires are brought out through the abdominal wall just beneath the
skin. The wires are attached to a small, battery-operated pacemaker that is
buried in a surgically-created pouch just under the skin. The skin is then
sutured so that the pacemaker and wires are beneath the skin. The pacemaker
generates electrical impulses that are transmitted by the wires to the muscles
of the stomach, and the muscles contract in response to the impulses. Electrical
pacing is effective in many patients with severe gastroparesis, but the numbers
of patients who have been treated is small. Since electrical pacing of the
stomach is relatively new, the long-term effectiveness and safety have not been
determined clearly.
Surgery. Surgery
occasionally is used to treat gastroparesis. The goal of surgery is to create a
larger opening between the stomach and the intestine in order to aid the process of emptying the stomach's
contents. Alternatively, the entire stomach may be removed. These procedures
should be considered only when all other measures have failed because of the
potential complications from the surgery. Surgery should be done only by
surgeons in consultation with gastroenterologists who are knowledgeable and
experienced in caring for patients with gastrointestinal motility disorders
(disorders of the nerves or muscles of the gastrointestinal tract
that affect
digestion and transport of food).
Maintaining nutrition
Patients with mild gastroparesis usually can be
successfully managed with pain relievers and pro-motility medications, but
patients with severe gastroparesis often require repeated hospitalizations to
correct dehydration, malnutrition and to control
symptoms.
Treatment options for dehydration and malnutrition include:
- Intravenous fluids to correct dehydration and
replenish electrolytes if nutrition is adequate but symptoms occasionally
interrupt the intake of even liquid food.
- Enteral nutrition
which provides liquid food directly into the small intestine, bypassing the
paralyzed stomach.
- Intravenous total parenteral
nutrition (TPN) to provide calories and nutrients (TPN is a fluid containing
glucose, amino acids, lipids,
minerals, and vitamins-everything that is needed for adequate
nutrition-intravenously. The fluid usually is delivered into a large vein via
a catheter in the arm or upper chest.)
Doctors generally prefer enteral nutrition over TPN
because long-term use of TPN is associated with infections of the catheter and
liver damage. Infection can spread through the blood to the rest of the body, a
serious condition called sepsis.
Catheter-related sepsis often requires treatment with intravenous antibiotics
and removal of the infected catheter or replacement with a new catheter. TPN
also can damage the liver, most commonly causing abnormal liver tests in the
blood. TPN-induced liver damage usually is mild and reversible (the liver test
abnormalities return to normal after cessation of TPN), but, rarely,
irreversible liver failure can occur. Such liver failure may require liver
transplantation.
Enteral nutrition is safe and effective. The two common
means of delivering enteral nutrition are via naso-jejunal tubes or jejunostomy tubes.
The jejunum is the part of
the small intestine just past the duodenum, the first part of the small
intestine just beyond the stomach. Both naso-jejunal tubes and jejunostomy tubes
are designed to bypass the stomach and deliver nutrients into
the jejunum where they can be absorbed.
A naso-jejunal tube is a long, thin
catheter inserted (usually by a radiologist or a gastroenterologist) via
the nostril into the stomach. The tip of the naso-jejunal tube is then advanced past
the stomach into the small intestine. Often this must be done during upper GI
endoscopy. Liquid nutrients then can be delivered via the naso-jejunal tube into
the small intestine. Naso-jejunal tubes generally are safe, but there are
cosmetic disadvantages and discomfort of having a tube in the nose. The problems
that occur with naso-jejunal tubes are primarily accidental or intentional
removal by the patient, blockage of the tube by solidified nutritional
solutions, and aspiration (backup of
stomach contents into the lungs that can
lead to pneumonia).
A jejunostomy is a catheter placed directly into the
jejunum. It can be done during standard abdominal surgery, using minimally
invasive techniques (laparoscopy), or by a specially-trained radiologist. With a
jejunostomy, the catheter passes through the skin on the abdominal wall and
directly into the jejunum. Before a jejunostomy is placed, a trial of
naso-jejunal nutrition often is given to be certain that the small bowel is not
involved with the same motility problem as the stomach and that nutritional
liquids infused into the small intestine will be tolerated.
Next: What is the prognosis (long-term outcome) for patients with gastroparesis? »
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