Constipation (Gastrointestinal Pathologies) Flashcards
What is Constipation?
The slow, difficult or infrequent movement of feces through the bowel
Is considered a symptom and not an actual condition
There are varying opinions on what constitutes “normal” bowel regularity
Generally, medical sources agree that a comfortable bowel movement daily or as little as 3x/wk fall within normal limits, which is largely based on the diet of western population
The digestive process functions to break down food into basic components that are absorbed into the bloodstream through the walls of the small intestine
The unusable and undigested food, referred to as chyme, has a fluid consistency and moves from the small intestine to the large intestine (colon)
The Large Intestine (colon)
The large intestine functions to absorb water to develop a soft, formed feces and to store the feces until it can be expelled from the body
- It is comprised of:
- The cecum, to which the appendix is attached
- The colon, which is divided into the ascending, transverse, descending and sigmoid sections
- The rectum which lies just anterior to the sacrum and coccyx. The distal portion of the rectum is called the anal canal which terminates with the anus
Movement in the Digestive System
Movement through the intestines is controlled by an intrinsic nervous system that lies within the GI walls
This network includes the enteric nervous system and the ANS
The enteric nervous system controls the muscular contraction of these structures
The ANS is comprised of the SNS and PNS which innervate the GI tract
The PNS functions to support the digestive process through the vagus nerve and the sacral nerve plexus
The SNS has an inhibiting effect on the digestive process through the nerves from the thoracic and lumbar portions of the spinal cord
Movement in the Colon
- Segmental movements:
Sometimes referred to as mixing movements. “Contain” the fecal matter so absorption of substances can occur through the intestinal walls and into the bloodstream. In the small intestines nutrients are absorbed and in the large intestine water and electrolytes are absorbed
- Propulsive contractions:
Those which move the fecal matter through the colon towards the anus
- Peristalsis:
Refers to smaller, more frequent propulsive contractions
- Mass movements:
Refers to infrequent but powerful propulsive contractions in the large intestine. Over a 24 hour period, an average of 4-6 mass movements occurs
Transit Times
The speed with which the fecal matter moves through the large intestine is referred to as the transit time
An optimal transit time will result in a soft, formed stool
The average time is 24-48 hours from ingestion of food to defecation
A harder, more difficult to pass stool is the result of an increased transit time since this allows more water to be absorbed
A faster transit time reduces the time available for water to be absorbed which results in a less formed, more liquid stool as is found with diarrhea
Hormones, emotions and diet are some of the factors that can influence transit time
Autointoxication Tự nhiễm độc
“Autointoxication” due to chronic constipation has been blamed for many illnesses
Many of those experiencing constipation also suffer a multitude of other symptoms such as headaches, nausea and irritability which are sometimes considered to be due to the toxic effect of retaining the fecal matter
Elimination
Is the combination of coordination of reflexes with conscious effort
At the distal colon, the rectum is followed by the anal canal where there are two sphincters
The first is the internal anal sphincter which opens when pressure occurs on the walls of the distal colon and on the sphincter itself which requires about 100-200 grams of feces to inititate the reflex controlled by the PNS
The fecal matter then moves further into the rectum, just proximal to the external and sphincter
Sensory receptors perceive the pressure and signal the brain with the “urge” to defecate
A person can consciously relax the sphincter which is coordinated with a voluntary contraction of the diaphragm and abdominal muscles to increase the intrapelvic pressure
The pelvic floor muscles along with the anus and the surrounding muscles relax
The result is defecation
Lifestyle Causes
- Poor diet
- Due to low fibre and low water intake or low food intake
- Results in decreased bulk of the fecal matter
- Sedentary lifestyle:
By choice or due to illness
- Resisting the urge:
Due to poor or inadequate toilet facilities, travel or lack of an appropriate opportunity to defecate
- Stress
- Postural imbalances:
May contribute to the inability of the abdomen, diaphragm, low back and gluteal muscles to contract effectively
Physiological Causes
- Poor muscle control or muscle tone or lack of coordination
- Psychological factors:
Such as depression, eating disorders, obsession - Medication side effects
Occurs with opiates, anticholinergics, antidepressants and anticonvulsants - Post-surgery side effects:
Especially abdominal surgery, which results in paralytic ileus (the absence of motor activity in the large intestine for approx 72 hours and incoordination of the stomach and small intestine function for 24 hours)
- Gastrointestinal conditions:
Such as irritable bowel syndrome, diverticular disease, megacolon, obstruction, colorectal cancer
- Physiological and structural disorders:
Such as rectal prolapse or internal and external sphincter abnormalities
- Pregnancy and early postpartum:
The first six weeks after childbirth
- Underlying disorders:
Such as hyperthyroidism, hypercalcemia and diabetes as well as neurological disorders such as Parkinson’s, MS and sacral lesions
Laxatives
Many people who experience constipation do not seek medical attention and commonly they self-prescribe laxatives to establish what they perceive as a “normal” bowel frequency
- Bulk laxatives:
increase the ability of fecal matter to hold water which increases fluid to facilitate normal colon movements (ex. psyllium)
- Laxatives containing salts such as magnesium hydroxide or sulphates:
these act by osmosis, they retain water in the stool which leads to hyperperistalsis because of increased pressure in the colon. Stools are often watery
- Laxatives containing unabsorbed sugars and polyhyrialcohols-these make use of the intestinal bacteria, fermentation by the bacteria which are 80% water which results in increased bulk of the stool. This allows more efficient transit time
- Laxatives such as senna, cascara and aloe (arthraquinone laxatives from plants)-they stimulate colon motility. Dosages are carefully monitored until a soft, formed stool results
Symptom Picture
- Straining, pain or discomfort may be experienced when passing stools
- Infrequent bowel movements occur
- Hard stools, which may be small are passed. These stools may be interspersed with softer stools, even diarrhea
- Abdominal pain, cramps, or discomfort may occur intermittently
- Low back pain or discomfort can result
- Bloating and flatulence are experienced
- Hemorrhoids can results from straining
- A bad taste in the mouth, bad breath, nausea and a lack of appetite can result due to slowing of gastric emptying which results with constipation
- Headaches, irritability and malaise seem to result reflexively from the distention of the rectal wall
Health History Questions
- How is the client’s general health?
- What indicates to the client that he is constipated?
- Is the client taking any medications that could result in constipation as a side effect?
- Has the client consulted a physician?
- Does the client have any idea what may be causing the constipation?
- How long has this been present?
- How frequently is the person having a bowel movement? Is it different from their normal patterns?
- What is the consistency of the fecal matter?
- What is the colour of the stools?
- Is there any pain present?
- What aggravates the pain? What relieves the pain?
- Has the client done anything to relieve the constipation?
- Are laxatives used? If so, what kind and how frequently?
- What is the client’s general lifestyle? What are the stress levels?
Observations
Bloating of the abdomen
A postural assessment is performed to check for imbalances such as hyperlordosis and a shortened psoas major which is contact with the colon
Abdominal muscles that are stretched and weak can lead to difficulty bearing down to facilitate defecation
Posterior pelvic tilt results in shortened diaphragm and abdominal muscles
Palpation
The distended abdomen may feel firm, often in the distal colon
Tenderness is often palpated along the colon, especially distally
Hypertonicity or hypotonicity of abdominal muscle is possible
Hypertonicity may also be present in the diaphragm and the gluteals as these muscles are often contracted to control the urge to defecate
Differentiating Other Conditions:
- Inflammatory Bowel Disease
- Appendicitis
- Obstruction of the Colon
- Inflammatory Bowel Disease:
a. Ulcerative Colitis-results in frequent bloody and loose stools
b. Crohn’s disease-results in periods of abdominal, hip and low back pain which is often relieved after a bowel movement or passing gas
- Appendicitis:
May be positive by a positive rebound test
Symptoms are nausea, vomiting, low-grade fever and pain the lower right quadrant. This can potentially be a medical emergency
- Obstruction of the Colon:
This is a medical emergency especially in the very young and elderly
Symptoms include absence of defecation, distention of the abdomen, vomiting and pain
The block frequently occurs in the rectum which often results in leakage of fecal matter around the blockage and decal soiling
