Digestive System


What are the 2 types of nausea and what causes them?


Central Nausea: Major trigger inside of the brain outside of the blood-brain-barrier (BBB) the CTZ zone is detected and senses things that are inside of our body that are not supposed to be, and will cause the body to want to eliminate that thing

Local Nausea: Other nausea is related to distention in the stomach


What is the process of vomiting and what is it coordinated by?


Coordinated by the somatic nervous system

1) Diaphragm descends2) Abdominal muscles contract3) Gastric cardia open


Vomiting Center (VC) vs. Chemoreceptor Trigger Zone (CTZ)


VC: located in the medulla; coordinate the respiratory, GI, and abdominal muscles; the common pathway that mediates comiting from all causes

CTZ: accessible to blood and cerebrospinal fluid (CSF); helps to induce vomiting


What neurotransmitters are involved in the CTZ associated with N & W


Dopamine,OpiateSerotoninAcetylcholineHistamine


Signs associated with N & V that are serious and require more intervention


Blood in vomitusAbdominal pain/distensionFeverSevere headableRecent traumaDiabetes


What is the function of CCK?


stimulates the gall bladder


What is function of gastrin?


Stimulates secretion of gastric acid adn pepsinogen, increases GI blood flow


What is function of Ghrelin?


Stimulates hunger

(may be useful in weight loss/obesity treatment by helping people to stop feeling hungry)


What is the function of GLP-1?


Supresses glucagon, slows gastric emptying


What is the function of GIP?


augments insulin release


What is the function of secretin?


Stimulates the production of bicarbonate in the stomach


What do parietal cells secrete?


HCL and intrinsic factor


What is the function of intrinsic factor?


To absorb vitamin B12 in the GI tract and prevent anemia


What do the chief cells secrete?


Gastrin


What are the 3 types of parietal cell receptors?


Histamine

Gastrin

ACH


Large volume vs. small volume diarrhea


Large volume: viral or bacterial infection; can cause K+ loss and acidosis

Small volume: frequent loss of small amounts of stool; characteristic of ulcerative colitis and Crohn's disease


What is the total amount of fluid secreted from the GI tract in a day?


7,100 mL


What is the best indicator of fluid status?


Body weight


What are the major risk factors for geting constipation?


AgeMenopauseEnlarged prostate


What is GERD, what are the major symptoms, and what are the causes?


GERD= backflow of GI contents into the esophagus because of a weakened cardiac spincter

Symptoms= heartburn, regurgitation

Causes= high-fat diet, pregnancy, obesity, congenital defects


What is gastritis, what causes it, and what do you use to treat it


Gastritis- the inflammation of the stomach that happens when anything disrupts the stomach's protective mucus lining

Causes by:H. pylori (acute)Degeneration of the stomach wall, pernicious anemia (chronic)
You use flagle to treat acute gastritis


What is a peptic ulcer, what is it caused by, and how is it diagnosed?


Peptic ulcer= erosion of the mucosal layer in the GI tract

Caused by H. pylori, decreased mucus production (from excessive use of NSAIDs/aspirin), increased acid production (caffiene, alchohol, and nicotine)

Diagnosed by gastroscopy, endoscopy, blood test, occult blood


What are the symptoms of peptic ulcers?


Pain in stomach

Pain immediately after eating

Weight loss/gain

Hematemesis

Melana (blood in the stool)

Dyspepsia (heart burn)


Signs of GI bleeding


hematemesis

hematochezia (blood in rectum)

melena

occult bleeding


What is peritonitis, what causes it, and what are the symptoms/treatments?


Peritonitis= inflammation of the peritineum

Causes= perforation of the gut of orgon into perineal space

Symptoms: pain, n/v, rigid abdomen, tachycardia, fever, increased WBC

Treatment: antibiotics, shock prevention (fluids, dopamine, etc)

*high risk for septicimia and septic shock*


Intestinal obstruction: causes, signs/symptoms, what will happen if left untreated


Causes= tumors, adhesions, volvulus (where bowel is tied in a knot), intussuception (bowel tunnels into another), severe constipation

Signs: pain, distention, n/v, anorexia, diarrhea, reduced/abscent BS, abdom tenderness, fever


What is an ileus, what causes it, and what are the symptoms?


Ileus: paralysis of the bowel; usually happens post-op

Causes: abdom surgery, reduction of blood supply to abdomen, kidney/heart disease, medications

Symptoms: abdom cramping/distention, N/V, failure to pass gas/stool


Crohn's disease vs. ulcerative colitis


Crohn's has patchy inflammation over all of the GI tract, diarrhea w/o blood, malabsorption, LRQ pain

Colitis: bloody diarrhea mixed with mucus, fever, weight loss, LLQ pain, n/v


Gallbladder disease: symptoms


Symptoms= jaundice, visceral pain, clay colored stool, steatorrhea (fatty stool)


Pancreatitis: symptoms, treatment


Symptoms= RUQ pain, vomiting, tender abdomen, high amylase/lipase

Treatment= supportive care only


Portal hypertenion: definition, complications, symptoms


Portak hypertension: increase in portal vein pressure due to obstructed blood flow

Leads to development of collateral veins, substances that are normally filtered by the liver may bypass and circulate in the blood

manifestations: eopshageal varicies, hemorrhoids, enlarged veins, ascites