Intestinal obstruction: see what symptoms and treatments


What is intestinal obstruction?

Intestinal obstruction is a syndrome characterized by difficulty or total impediment of the passage of intestinal contents, such as food mass, swallowed air and secretions produced in digestion.

This content accumulates totally or partially in the intestinal tract and causes pain, inflammation and, in some cases, serious complications, such as necrosis of the intestinal walls.

The main causes are the absence or reduction of contractions of the intestinal muscles, caused by inflammation, infections or adverse reactions to medications, twisting of the intestinal tube or, still, organ compression, caused by tumors, abscesses or elements external to the body.

It can occur throughout the large or small intestine, including the duodenum (the first part of the intestine), the syndrome causes swelling and inflammation of the intestinal tissue due to the accumulation of substances, resulting in varying levels of pain and degrees of urgency.

The correct functioning of the intestinal transit is part of the proper functioning of the digestive system, ensuring that nutrients are properly absorbed, and that non-digestible parts are eliminated along with other biological excreta.

When the bolus reaches the small intestine, it is called chyme and constitutes a previously digested mass, loaded with gastric juices and digestive enzymes. The route follows from the small, large intestine and the colon, where non-absorbable waste will be eliminated by the body. When this path is not correctly performed, there is intestinal obstruction.

The intestine

The small intestine is located in the middle part of the digestive tract and connects to the large intestine. The organ is responsible for most of the digestion and absorption of nutrients, making the assimilation of food compounds.

Digestion is a process initiated in chewing, which continues to break down food into smaller and smaller particles, facilitating the absorption of nutrients. Upon reaching the small intestine, the ingested content is called kilo, a compound of molecules and loaded with vitamins and minerals.

These components are absorbed by the microvilli present in the small intestine and, after being absorbed, the molecules are spread through the body’s cells, feeding and nourishing the body.

However, not everything is taken advantage of. A percentage of water and non-absorbable food is sent to the large intestine.

The large intestine is divided into three parts: the cecum, colon and rectum. It is mainly in the colon that the food mass gains consistency, being directed to excretion. The transit of the fecal bolus is aided by mucous glands in the large intestine, which secrete mucus and facilitate the elimination of waste.

Obstruction in babies

Children and newborns may have intestinal obstruction. However, due to the difficulty in establishing the symptoms, the diagnosis may take time to occur. In general, the picture has no apparent reasons, and only 5% of cases are related to tumors, intestinal infections, enlarged ganglia or suppression of the intestinal wall.

After delivery, the baby’s first evacuation is expected to occur within 24 hours, expelling meconium (a pasty, greenish substance found in the newborn’s intestine). After that time, intestinal obstruction is suspected, which is confirmed when 48 hours without evacuation is reached.

The most recurrent causes of intestinal occlusion in babies are:

  • Intestinal atresia (narrowing of the intestine);
  • Rotation defects (malformation of the intestine);
  • Meconium ileum (obstruction by meconium);
  • Hirschsprung’s disease;
  • Meconium stopper syndrome;
  • Anorectal anomalies.

The child usually presents with vomiting, cramps, bloating and pain. Irritation tends to appear as a symptom and, in newborns, constant crying can be a denunciation of the syndrome.

The procedure to diagnose the obstruction follows the adult medical standard: ultrasound and X-ray examinations are performed .


Intestinal obstruction can be classified into 3 categories, according to the degree, severity and mechanism.

Intestinal obstruction by degree

Classified as complete , in which there is no passage of substances, whether liquid or pasty, aggravating the risk to health, and the partial , in which it is difficult for certain compounds to be sent to the end of the intestinal tube, blocking part of the digestive flow.

Intestinal obstruction by gravity

The syndrome can be simple , in which there is only the impediment or difficulty of intestinal transit, or complicated , in which there is intestinal strangulation.

Strangled intestinal obstruction

Also called closed-loop strangulation, the complicated type compromises blood supply and worsens symptoms, increasing the possibility of tissue death.

In this case, there is a circulatory impediment caused by hernias, twists or invaginations in the tube, configuring a knot in the folds of the intestine. Therefore, blood circulation and irrigation are compromised, which can result in necrosis and tissue death.

Intestinal obstruction by mechanism

The types of mechanisms are divided into functional , in which the obstruction is caused by an abnormality of the intestine, and mechanical , in which there is an agent causing the obstruction.

Functional obstruction or paralytic ileus

This type is defined by the inability of the intestine to perform the peristaltic movements, in which there is no proper contraction of the intestinal muscle fibers that route the excrement along the intestine.

The main factors of obstruction are the use of drugs that interfere with the intestinal process, metabolic disorders, bacteria or viruses that affect the intestine, disturbances in hydration, food poisoning or by materials such as lead, called saturnism.

Also known as paralytic ileus, the functional syndrome occurs in the postoperative period related to the intestine.

Mechanical obstruction

It is caused by the presence of some element preventing the correct digestive functioning, in general, inflammation, tumors, anomalies of the muscular wall or elements that can cause compression or flattening of the intestinal tube.

The region in which the mechanical obstruction occurs may still have different causes. In the case of the small intestine ( high obstruction ), the main occurrences are:

  • Hernias;
  • Adhesions (post-surgical);
  • Tumors of the small intestine;
  • Inflammatory diseases;
  • Bowel twists;
  • Gallstones (pressing or blocking intestinal flow);
  • Invagination or displacement of part of the intestinal tube.

However, obstruction in the large intestine or colon ( low obstruction ) is less recurrent. The main factors that can cause occlusion are:

  • Colon and rectal cancer;
  • Diverticulitis; colon torsion;
  • Stool density and dryness;
  • Stenosis (inflammation and intestinal scarring that cause the colon to narrow).


A large part of the obstructions are caused by congenital factors, that is, which were formed during pregnancy. They are the reduced rate of intestinal transit, metabolic problems and intestinal dysfunctions.

However, mechanical obstructions can be caused by poor healing after surgery or inflammation, resulting in hard tissue that blocks or compresses the intestine, or even illness.

The main factors that affect functional or mechanical obstruction are:


They represent a fibrous tissue that develops in the intestine, connecting the intestinal tubes to each other or to nearby organs. The elevations formed can also push the intestine out of place, allowing it to twist or fold.

The condition represents up to 70% of the cases of intestinal obstruction and, generally, they are of congenital order.


They are membranes that form in the healing of intestinal tissues after surgical or inflammatory procedures. Due to the proximity of the organs, there is a greater propensity to develop adhesions, improperly linking the tissues through tissue membranes.


Diverts are small pockets or bumps that form on the intestinal wall. In most cases, it is an asymptomatic condition, but when symptoms are present, the condition is configured as diverticulitis , which is inflammation of the organ tissue. In this case, the obstruction is caused by the accumulation of feces in the organ, favoring the proliferation of bacteria.


Volvulus are twists in the loops of the intestine that cause intestinal strangulation. Due to the lack of blood supply, the condition worsens rapidly, causing the tissue to die within 12 hours.


It is the abnormal proliferation of tissues caused by cellular dysregulation, which can be a malignant or benign syndrome. When the syndrome is malignant, an intestinal tumor appears.

Strangulated hernias

The hernia is caused by the rupture of part of the intestinal muscle wall due to its weakening. Muscle tissue is responsible for supporting the organs and, when ruptured, allows the displacement of the intestine that is improperly accommodated through the ruptured tissue.

This condition decreases blood flow to the rest of the intestine, which can lead to tissue necrosis.

Inflammatory disease and Crohn’s disease

Inflammatory diseases are common causes of obstruction. In Crohn’s disease , the intestinal wall thickens, while the tube space narrows, making it difficult for excrement to pass.

Intra-abdominal abscess

It is characterized by the presence of pus or intra-abdominal infection, usually associated with some disorder of the organism.

The causative agents can be bacteria, fungi or parasites, and it is necessary to investigate the cause of the problem because the abscess changes or prevents the proper functioning of the affected part, making it difficult for the intestinal contents to pass.

Intestinal torsion

The torsion can be caused by changes in the shape of the intestine, tumors or inflammation, incorrect healing after surgery or chronic constipation.


The functional obstruction , in which there is loss of intestinal wall movements can be caused by medications such as anticholinergics, opioid, calcium channel blockers and electrolyte disturbances, antidepressants, and antihistamines, for example.

These chemicals can decrease peristalsis, movement of muscle contraction of the intestinal tube, either by adverse reactions expected from the medication itself, or by the body’s response to the compound.


In addition to drug interactions, post-operative can compromise the intestinal rhythm and cause obstructions during the recovery period.

Groups of risk

Intestinal obstruction affects, in large part, patients undergoing surgical procedures, diagnosed with inflammation or infections in the digestive tract, in addition to pathologies related to the intestine, such as inflammatory or infectious diseases.

Patients in the postoperative period or with chronic pathologies may show a decrease in immunity, favoring that infections settle and generate greater damage.

When there is a family history of cancer or the patient has inflammatory pathologies of the intestinal tract, the risks are higher and it is necessary to be attentive to symptomatic manifestations.


The symptoms and signs of intestinal obstruction essentially depend on the severity – complete or partial obstruction -, in addition to the intestinal location. The most frequent observations are:

  • Pains and cramps;
  • Change in stool consistency and evacuation frequencies;
  • Abdominal distension;
  • Flatulence;
  • Decreased appetite;
  • Swelling;
  • Constipation;
  • Fever and tachycardia (in cases of strangled obstruction).

There is also the presence of vomiting and nausea caused by water decompensation, which affects levels of body hydration, which can lead to extreme fatigue and pressure drops.

How is the diagnosis made?

The medical specialties most capable of identifying and diagnosing intestinal obstruction are the gastroenterologist and coloproctologist , who deal with abnormalities and functionalities of the digestive tract and, specifically, diseases of the intestine.

The symptoms are quickly noticed in the intestinal block, being a first alert to seek care and make the diagnosis. Suspected intestinal obstruction is followed by physical, imaging and blood tests, which confirm the diagnosis and help determine whether the obstruction is total or partial, caused by internal or external agents.

Differential diagnosis

An accurate diagnosis will eliminate the possibility of other causes of intestinal obstruction. In some cases, it is possible that symptoms may be similar in quite different diseases and syndromes.

Among them, gastroenteritis , which is an inflammation and infection of the digestive tract, can cause pain and vomiting, but abdominal swelling and changes in intestinal transit are rarely noticed.

Elevated levels of amylase (digestive enzyme produced by the pancreas) are present in the diagnosis of intestinal obstruction, but are also associated with pancreatitis , which is inflammation of the pancreas.

Among the frequent symptoms, fever , vomiting and abdominal pain, there is also the possibility of abdominal perforation, peptic ulcer (wound that affects the tissue of the stomach, esophagus or duodenum) and tuberculosis that can be confused with the condition of obstruction of the intestine.

Physical exams

Usually started with abdominal cramps and pain, nausea, vomiting and bloating, the intestinal syndrome is confirmed by physical examinations , in which the bloating of the abdomen and the presence of visible irregularities in the intestinal tube are observed.

To check the most painful and distended regions, the doctor palpates the abdomen and performs auscultation, a procedure performed with the stethoscope (a tool that the doctor uses to listen to the heart and other organs). The presence of high-pitched sounds indicates mechanical obstruction, while the absence of sounds represents functional obstruction.

If there is pain centered on the right and below the navel, in the right iliac fossa, there is an indication of acute appendicitis with abscess. Pain centered on the left flank, on the left side of the navel, indicates complicated diverticulitis. Both cases can lead to intestinal obstruction.

Digital rectal examination can be performed to investigate the presence of tumors in the rectum.


Blood tests can help determine obstructive causes. The anemia can indicate inflammatory diseases and neoplasms (or irregular formation of tissue growth).

Blood tests will also determine whether the levels of electrolytes (sodium, potassium, chlorine, for example), urea and creatinine are adequate, determining whether kidney function is normal. Changes in the kidneys can cause cases of dehydration and lead to obstruction of the intestine.

Imaging exams

Imaging exams make up the diagnosis because, often, the identification of the obstruction is hampered by the presence of mild symptoms. A physical examination in the first 24 hours of the obstruction, in general, indicates few anomalies besides abdominal pain.

It is only after 2 to 3 days that the symptoms worsen, the distention of the abdomen and dehydration are very noticeable, and may even present changes in the heart rhythm.

A simple abdominal radiography, with the patient lying and standing, is one of the most requested tests in the case of suspected intestinal block. In it, it is possible to identify the gas distension of the intestinal loops, the presence of liquids and air in the segments of the intestine.

However, if there are many dilated loops, the diagnosis becomes less efficient, and it is necessary to resort to other tests.

In children, ultrasound is widely used. The examination facilitates the identification of intestinal folds or kinks.


When there is difficulty in identifying the presence of mechanical obstruction or when there is a suspicion of obstruction in the colon (large intestine), colonoscopy is very effective. Through the insertion of a tube with a camera through the rectum, the examination allows the elimination of mechanical obstructions and the assessment of tissue conditions in the intestine.

It is also possible to inflate the intestine through the rectum. The practice favors the observation of the walls of the intestinal tube, facilitating the identification of lesions, necroses or infections caused by the excrement obstructed in the intestine.

Can intestinal obstruction be cured?

There is a cure for the syndrome through treatments or emergency interventions, such as surgical ones.

In cases where the obstruction is the result of tumors or chronic pathologies, treatment results from the control of primary diseases, providing improvements in intestinal functioning.

What is the treatment?

Intestinal obstruction is treated and, in general, offers good results to patients. When the condition is a symptom of other pathologies or external factors, such as tumors or reactions to medications, the procedure should be directed to address the main problem.

In cases where there are no agents triggering the intestinal malfunction, it is necessary to resort to emergency care to perform intestinal lavage or, in more severe cases, perform a surgical intervention.

The use of serum and hydroelectrolytic repositories is necessary for organic stabilization, especially when there are signs of dehydration and vomiting.

In cases of fatigue and cardiac and respiratory disorders, oxygen cylinders are recommended to improve cardiorespiratory conditions.

Treatment for partial obstruction

The partial obstruction presents itself in a less serious condition, as it still allows some foods or liquids to pass through the intestine, decreasing the intensity of the symptoms.

Even in mild cases, hospitalization is recommended for the patient’s follow-up.

In this case, after clearing, eliminating fluids and stabilizing the intestinal system, one must take care of food and hydration, ingesting adequate amounts of water and fibers, guaranteeing the good conditions of the digestive tract.

Treatment for functional obstruction

In the case of functional obstruction, it is necessary to resort to observation and identification of the causes. Generally, fasting and aspiration of intestinal contents is recommended, proceeding with the correction of hydroelectrolytic changes.

Paralytic ileus, or functional obstruction, is usually a temporary condition and requires non-invasive treatments, such as medications that cause an increase in intestinal muscle contractions.

Suction via nasogastric tube

This emergency clinical treatment consists of placing a nasogastric tube (SNG) to hydrate the body and correct hydroelectrolytic disorders. The probe reaches the stomach through the nose, draining the secretions, which can be clear and bilious (from the production of bile), or brown and fetid.

Fluids administered intravenously

The procedure aims to restore body hydration levels and stabilize hydroelectrolytic disturbances caused by the decompensation of sodium, potassium and chlorine, for example.

Treatment for complete obstruction

Complete obstructions are considered more serious and commonly require emergency surgery to prevent or combat permanent damage.

In cases of patients at risk or with colon cancer, it is possible that the doctor may indicate a self-expanding stent as a treatment measure. This device is inserted through an endoscope to help keep the passage open, forcing the colon to open.


In order for the surgeon to determine what the procedure will be and if there is a need to remove a segment of the intestine, the professional will analyze factors such as the cause of the obstruction and which region was affected.


The procedure can perform partial or total removal of the large intestine. It is indicated when there is severe damage to the intestinal wall due to obstruction, such as bleeding from the uncontrollable colon.

Strangulation surgery

When there is undue displacement or folding of parts of the intestine, it is necessary to subject the patient to surgery. In cases of strangulation of the intestine, the condition can result in decreased blood supply and result in a rapid evolution to gangrene , or tissue death.

The greatest danger is not seeking immediate care or not identifying the sources that cause the syndrome, resulting in irreversible complications, such as intestinal necrosis or life-threatening.

How is the surgery done for intestinal obstruction?

With technological advances applied to medicine, surgeries become less and less invasive. Currently, it is possible for the entire procedure to be done without the need for large cuts, using the minimally invasive surgical method.

About 5 small incisions are made close to the navel, inserting tubes to perform the unblocking. The intestine can be inflated for better visualization of the walls, identifying injuries or adhesions.

In colectomy surgery, a larger opening of the abdominal region may be necessary to remove the affected parts and, subsequently, to perform the ligament of the intestinal tube. But if there is total removal, the small intestine is connected to the anus.


To relieve nausea and vomiting, especially in post-surgical cases, the medications that can be indicated are:

  • Promethazine ;
  • Ondansetron.

Antibiotics are indicated to treat infections and bacterial action in intestinal tissues. Commonly used ones include:

  • Cefazolina;
  • Cefoxitina;
  • Cefepima;
  • Meropenem.

In cases of acute pain, analgesics are given in order to increase comfort and well-being, especially during recovery. The most recurrent is morphine sulfate .

The use of drugs with a laxative effect is not recommended due to the impact and the intestinal alteration caused. It is noteworthy that every medication must be indicated by a professional.


NEVER self-medicate or stop using a medication without first consulting a doctor. Only he will be able to tell which medication, dosage and duration of treatment is the most suitable for his specific case. The information contained in this website is only intended to inform, not in any way intended to replace the guidance of a specialist or serve as a recommendation for any type of treatment. Always follow the instructions on the package insert and, if symptoms persist, seek medical or pharmaceutical advice.


Cramping, abdominal pain, vomiting, distension and abdominal dilation are quite common symptoms and, in general, the first to appear in cases where the obstruction occurs. The evolution of symptoms is quite rapid, gradually worsening and increasing the risk of severe complications.

Initially, the syndrome may present partial closure of the intestinal tube, progressing to complete closure or causing the death of certain regions of the intestinal tissue.

When there is rapid intervention, the patient is at reduced risk of future complications. However, in long or untreated obstructions, there is the possibility of electrolyte imbalance, the onset or worsening of infections, and perforation of the intestine.

The outcome of the treatments depends on the condition and the causes of the obstruction. If the syndrome is the primary problem (not being a symptom of another disease), recovery is generally successful.

However, intestinal obstruction is rapidly evolving and, if not attended to on an emergency basis, results in a significant worsening of the patient. In cases undergoing surgery within the first 36 hours, the risk of death is an average of 8%. After that time, about 25% of cases result in death.

In cases of intestinal strangulation, there is a 50% recurrence in up to 2 years. Therefore, monitoring the picture is essential.

Elderly patients or those with weakened immune systems may have a slower recovery, in addition to being more susceptible to infections of the abdominal cavity and generalized infections resulting from the syndrome.


Dehydration and hydroelectrolytic disturbances

The obstruction of the intestine can lead to the improper secretion of liquids, generating a hypovolemia (low blood volume) and compromising the hemodynamic balance (referring to blood irrigation and water balance).

Bacterial super growth

The prolonged non-elimination of body fluids promotes the proliferation of bacteria in the intestine, causing infections that can spread to the rest of the body. There is a risk of progressing to a generalized infection , also called septicemia, which is more recurrent in children and newborns.

Necroses e gangrenas

Failure of part of the intestinal tissue is caused by small or absent blood circulation, usually due to suppression of the organs of the digestive system. The longer the time without blood supply, the greater the chances of infections of the abdominal cavity, called peritonitis , which can progress to necrosis and gangrene.

Post-surgical risk

Surgery is the procedure indicated in cases of urgency and severe obstruction, however, like any invasive procedure, it can bring risks, especially in the postoperative period. Due to low immunological status, intestinal wall infection, urinary tract infection , pulmonary complications and dysfunction of the intestinal rhythm can be observed.

How to prevent

Due to its multiple factorial characteristic, the ways of preventing intestinal obstruction syndrome are quite varied and sparse.

Pay attention to the general health of the organism

Because it is characterized as a syndrome, the causes of the obstruction may be unknown. It is important to pay attention to the functioning of the body, to adequate levels of hydration and renal function, in addition to observing gastrointestinal changes.

Therefore, adopt healthy habits, be aware of body signals (such as gastrointestinal changes) and have regular consultations.

Know the effects of medicines

Some remedies can alter the intestinal flow or favor the obstruction, being necessary to reinforce the ingestion of fibers, water or to initiate the use of medications that help the intestinal flora. So it is important to know if the drugs are causing side effects in your body.

Perform gastrointestinal monitoring

In the signs of alteration of the intestine, pain, difficulty in evacuation or change in the consistency of feces, it is recommended to seek a professional gastroenterologist. The doctor will assess the health of the intestinal flora, identify problems or dysfunctions, treat and improve intestinal health.

The intestines are responsible for the final part of digestion, assimilating nutrients and sending excreta out of the body. Obstruction and difficulty in intestinal flow can cause complications in other organs, in addition to the association with other diseases.

If your body is showing signs of intestinal dysfunction or irregularities, it is necessary to seek medical attention!