Digestive System Disorders

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Hello,

Interesting set of multiple questions! Let's take a closer look through researching each question, which you can then draw on for your final response. I also provided links for further information, if necessary.

RESPONSE:

6. A. Name the common electrolytes lost because of diarrhea.

The most common electrolytes lost because of diarrhea are sodium and potassium (see attached resource doe a full coverage).

The process: Extensive water loss is potentially a serious problem for anyone with severe diarrhea, but is particularly life-threatening in infants and small children. Adults normally lose 1,500-2,000 mL per day of water through urination and perspiration, even in cold climates. Diarrhea may cause additional high fluid losses, so the volume of fluid lost should be measured and an equal amount of electrolyte-balanced fluid should replace it. Water contains no electrolytes, so fruit juices, soft drinks, soups and similar liquids should be consumed. An alternative electrolyte replacement fluid contains 1 teaspoon of table salt (lost sodium) and 4 heaping teaspoons of sugar in a liter of water. Some liquids, such as tea, coffee and hot chocolate, are diuretics that encourage more fluid loss, and should be avoided. Urine color is a fairly reliable gauge of dehydration. Small amounts of dark yellow to orange urine suggest considerable fluid loss. (Note that rifabutin discolors the urine and renders this rule of thumb useless.) Oral re-hydration is usually sufficient to counterbalance the fluid losses due to chronic diarrhea, but intravenous fluids may be needed if the person is in shock or near shock, vomits persistently, or has ileus (an obstruction of the bowel). Lost potassium can usually be repleted by drinking 1 cup of orange juice or eating 2 bananas. Electrolytes must be monitored carefully in those who experience diarrhea as a result of taking foscarnet (http://www.sfaf.org/treatment/beta/b33/b33diar.html).

6. B. State the major effect on the body of sodium loss and of potassium loss.

The magnitude of the potassium gradient across cell membranes determines excitability of nerve and muscle cells, including the myocardium. Minor changes in serum potassium concentration can have major effects on cardiac rhythm and function. Of all the electrolytes, rapid changes in potassium concentration can cause the most immediate life-threatening consequences (see http://circ.ahajournals.org/cgi/content/full/102/suppl_1/I-217#SEC3).

An abrupt fall in serum sodium produces a free water shift from the vascular to the interstitial space that can cause cerebral edema. In this case the patient may present with nausea, vomiting, headache, irritability, lethargy, seizures, coma, or even death (see http://circ.ahajournals.org/cgi/content/full/102/suppl_1/I-217#SEC3).

6. C. State and explain what arterial blood gas levels may be expected in the presence of severe vomiting.

High pH combined with high HCO3 and PaCO2 - may be expected by prolonged vomiting (and other conditions) (see http://heart.health.ivillage.com/bloodtest/arterialbloodgases4.cfm).

Normal values may vary from lab to lab and depend upon the elevation above sea level. Results are usually available right away.

Chart: Arterial blood gases (at sea level and breathing room air)

Partial pressure of oxygen (PaO2): 75-100 mm Hg
Partial pressure of carbon dioxide (PaCO2): 35-45 mm Hg
pH: 7.35-7.45
Bicarbonate (HCO3): 20-29 mEq/L or 20-29 mmol/L
Oxygen content (O2CT): 15%-22% (15-22 mL per 100 mL of blood)
Oxygen saturation (O2Sat): 95%-100% (95-100 mL per 100 mL of blood)
(http://www.mountauburn.caregroup.org/body.cfm?xyzpdqabc=0&id=6&action=detail&AEProductID=hw_knowledgebase&AEArticleID=hw2343&AEArticleType=MedicalTest#hw2346).

8. Explain several ways in which severe stress can affect the digestive tract.

The brain and the intestine are strongly related and mediated by many of the same hormones and nervous system. (Indeed, some research suggests that the gut itself has features of a primitive brain.) It is not surprising then that prolonged stress can disrupt the digestive system, irritating the large intestine and causing diarrhea, constipation, cramping, and bloating. Excessive production of digestive acids in the stomach may cause a painful burning.

The following conditions can occur:

· Irritable Bowel Syndrome. Irritable bowel syndrome (or spastic colon) is strongly related to stress. With this condition, the large intestine becomes irritated, and its muscular contractions are spastic rather than smooth and wave like. The abdomen is bloated and the patient experiences cramping and alternating periods of constipation and diarrhea. Sleep disturbances due to stress can further exacerbate irritable bowel syndrome.

· Peptic Ulcers. It is now well established that most peptic ulcers are either caused by the H. pylori bacteria or by the use of non-steroidal anti-inflammatory (NSAID) medications (such as aspirin and ibuprofen). Nevertheless, studies still suggest that stress may predispose someone to ulcers or sustain existing ulcers. Some experts, in fact, estimate that social and psychological ...