GI/nutritional part 2

Question 1

Etiology of intestinal obstruction

Answer 1

Result of mechanical blockage or loss of nl peristalsis
Paralytic ileus more common and usually self-limiting
Mechanical etiologies of SBO: adhesions from prior surgeries, incarcerated hernias, inflammatory diseases
-Always ask about prior surgeries
LBO most commonly caused by neoplasm, diverticulitis with stricuture, sigmoid volulus

Question 2

Presentation of intestinal obstruction

Answer 2

Crampy, intermittent progressive abdominal pain with inability to have a bowel movement or pass flatus
Vomiting
-Bilious in proximal obstructions, feculent in distal obstructions
Abdominal distention
May have surgical scars, hernia or masses on exam that can provide clues to sight of obstruction
Localized to generalized tenderness
Active, high-pitched (tinkling or rushes) BS that later become absent
Tympany with percussion

Question 3

Workup of intestinal obstruction

Answer 3

Rectal exam and hemoccult
-Stool in rectum does not exclude obstruction
Labs: CBC, CMP
Imaging:
-Abdominal series (plain films) may show air-fluid levels and multiple dilated loops of bowel
-CT scan abd/pelvis (with IV contrast if possible) is diagnostic procedure of choice

Question 4

Tx of intestinal obstruction

Answer 4

IV fluid resuscitation, IV anti-emetics
NPO
NG tube to decompress bowel
+/- broad-spectrum abx (give if going to surgery or suspect infection)
-Zosyn or Unasyn OR Rocephin + clindamycin or Flagyl
Surgery consult and admission
In pts with pseudo-obstruction, colonoscopy is both diagnostic and therapeutic

Question 5

Upper GI bleed

Answer 5

More common than lower
Bleed originating proximal to ligament of Treitz
Causes:
-PUD
-Erosive gastritis or esophagitis
-Esophageal or gastric varices
-Mallory-Weiss syndrome

Question 6

Lower GI bleed

Answer 6

Bleed originating distal to ligament of Treitz
Causes:
-Diverticular dz
-Colitis
-Adenomatous polyps
-Malignancies
-IBD
-Trauma

Question 7

Presentation of GI bleed

Answer 7

Upper: hematemesis, melena
Lower: hematochezia
May present with signs of shock, hypovolemia, or hemodynamic instability
-Tachycardia
-Syncope
-Weakness
-Hypotension
-AMS
-Confusion
-Angina

Question 8

Workup of GI bleed

Answer 8

Labs: CBC, CMP, hemoccult and/or gastroccult, coag studies, type and cross
-Initial hematocrit level may not reflect actual amount of blood loss

Question 9

Tx of GI bleed

Answer 9

Stabilize ABCs
IV fluid resuscitation (consider 2 large-bore IVs)
NPO
O2
Cosnider transfusion
NG tube
Upper: PPI (pantoprazole)
Surgery consult and admission

Question 10

What is toxic megacolon?

Answer 10

Extreme dilation and immobility of colon, non-obstructive

>6 cm of transverse colon

Question 11

Cause of toxic megacolon in adults

Answer 11

Occurs as a complication of:

• Inflammation (IBD) or
• Infection (C. diff, CMV, shigella, campylobacter)

Question 12

Presentation of toxic megacolon

Answer 12

Severe abdominal pain
Signs of systemic toxicity: fever, tachycardia, AMS, hypotension
Abdominal distention
May have diarrhea that is often bloody
Rigid abdomen with diffuse or localized pain and rebound tenderness
Dehydration

Question 13

Workup of toxic megacolon: labs

Answer 13

CBC, CMP, lipase, hemoccult
Leukocytosis, anemia, electrolyte abnormality
+/- positive hemoccult

Question 14

Workup of toxic megacolon: imaging

Answer 14

Abdominal plain films (show colonic dilation)

CT abd/pelvis may be helpful

Question 15

Tx of toxic megacolon

Answer 15

Stabilize, fluid resuscitation, NPO
Correct fluid and electrolyte imbalance
NG tube
IV broad-spectrum abx
IV steroids
Surgical consult
-Decompression of colon
-Colostomy or complete colonic resection may be required

Question 16

Etiology of mesenteric ischemia

Answer 16

Caused by arterial embolus or thrombosis or venous thrombosis of a major mesenteric vessel
Leads to hypoperfusion, which leads to necrosis of bowel wall, which leads to sepsis, peritonitis, gangrene, death

Question 17

RFs of mesenteric ischemia

Answer 17

AFib
Recent MI
CHF
ATherosclerosis
Digoxin therapy
Past DVT
Liver dz
Hypercoagulability

Question 18

Presentation of mesenteric ischemia

Answer 18

Severe abdominal pain that may be sudden or gradual
-Classic clinical description: abdominal pain out of proportion to physical exam findings
-Often refractory to pain medication
Nausea, vomiting, anorexia common, +/- diarrhea
Abdominal exam relatively nl
As ischemia progresses, abdomen becomes grossly distended, absent BS, peritonitis develop

Question 19

Workup of mesenteric ischemia

Answer 19

Hemoccult pos (late finding)
Labs: CBC, CMP, serum lactate (elevated)
Imaging: CT abd/pelvis with IV CONTRAST ONLY

Question 20

Tx of mesenteric ischemia

Answer 20

Aggressive hemodynamic monitoring and support, fluid resuscitation
Restore blood flow ASAP
GI decompression- NG tube
Correct metabolic acidosis
Anticoagulation (usually): heparin or LMWH
Broad-spectrum abx
Surgical consult for revascularization ASAP
-Do not delay consult if obvious infarct, perforation or peritonitis

Question 21

Incarcerated hernia

Answer 21

Contents of hernia are not reducible

Can lead to bowel obstruction and strangulation

Question 22

Strangulated hernia

Answer 22

Vascular compromise of incarcerated contents
Acute surgical emergency
Can lead to gangrene, perforation, peritonitis, septic shock

Question 23

Presentation of hernia

Answer 23

Abdominal pain localized to mass, severe if strangulated
Nausea, vomiting
Induration and erythema may be present if strangulated
Protruding mass on exam
-May be more obvious if ask pt to lift head off table while in supine position

Question 24

Workup of hernia

Answer 24

CT abd/pelvis

Labs have limited value

Question 25

Tx of incarcerated/strangulated hernias

Answer 25

Emergent surgical referral NPO IV fluids, IV pain control, IV broad-spectrum abx

Question 26

Diarrhea

Answer 26

3 or more watery stools/day

Question 27

Workup for diarrhea

Answer 27

Pts with abdominal pain, fever, and bloody diarrhea should undergo stool studies CBC, CMP Consider hemoccult

Question 28

Tx of diarrhea

Answer 28

``` Correct fluid and electrolyte problems BRAT diet as tolerated Anti-motility agents -Loperamide, bismuth subsalicylate -No if bloody or suspected inflammatory diarrhea Abx for infectious diarrhea -Cipro, Flagyl, Vanc, etc (depends on bug) -Acute infectious and TD: Cipro, Flagyl -C. Diff- Flagyl, Vanc Education -Hand washing, work excuses Admission if toxic or complications ```

Question 29

Pathophysiology of constipation

Answer 29

There could either be issues of stool consistency or issues of defecatory behavior

Question 30

Etiology of constipation

Answer 30

``` Primary constipation: Normal-transit constipation- MCC of primary constipation Slow-transit constipation Pelvic floor dysfunction Secondary constipation: Dietary issues Structural causes Systemic diseases Meds Toxicologic Psychological issues ```

Question 31

Hx of constipation

Answer 31

``` General: Abdominal bloating Pain on defecation Rectal bleeding Spurious diarrhea LBP Suggest that pt may have difficult rectal evacuation: Feeling of incomplete evacuation Digital extraction Tenesmus Enema retention ```

Question 32

S/sx of constipation that are grounds for particular concern

Answer 32

``` Rectal bleeding Abdominal pain Inability to pass flatus Vomiting Unexplained wt loss ```

Question 33

Questions regarding constipation hx to ask

Answer 33

Detailed inquiry into the pt's nl pattern of defecation Frequency with which the current problem differs from the nl pattern Perceived hardness of the stools Whether the pt strains in order to defecate Amount of time spent on the toilet while waiting to defecate and what maneuvers used to treat

Question 34

PE of constipation

Answer 34

``` Abdominal distention or masses may indicate the presence of colonic stools or tumors Pelvic exam in women may reveal internal prolapse or rectocele Assess in rectum: -Perianal excoriation -Skin tags/hemorrhoids -Anal fissure -Anocutaneous reflex -Prolapse during straining -Stool amount and consistency ```

Question 35

Workup of constipation

Answer 35

``` CBC CMP TSH Radiography in acute abdominal pain, fever, leukocytosis, and other sx suggesting systemic or intra-abdominal processes CT Barium study Defecography Colonic transit study Lower GI endoscopy Anorectal manometry ```

Question 36

Tx of constipation

Answer 36

``` Increased fiber intake Increased fluid intake Failure of diet changes: look into compliance and search for other physical causes Bulk agents Emollient stool softeners Rapidly acting lubricants Prokinetics Laxatives Osmotic agents Prosecretory drugs Surgery for the tougher problems ```

Question 37

Pathophys of hepatitis

Answer 37

Hep A: Virus excreted in stool during first few weeks of infection, before onset of sx (15-45 day incubation period) HepB: Incubation period, 40-150 days Transmitted through parenteral or sexual transmission Hep C: Incubation period of 8 wks

Question 38

4 phases of hepatitis: phases 1 and 2

Answer 38

``` Phase 1 (viral replication phase)- pts are asymtomatic; lab studies demonstrate serologic and enzyme markers of hepatitis Phase 2 (prodromal phase)- Pts experience anorexia, nausea, vomiting, alterations in taste, arthralgias, malaise, fatigue, urticaria and puritis, and some develop an aversion to cigarette smoke. When seen by a healthcare provider during the phase, pts are often diagnosed as having gastroenteritis or a viral syndrome ```

Question 39

4 phases of hepatitis: phases 3 and 4

Answer 39

``` Phase 3 (icteric phase)- Pts may note dark urine, followed by pale-colored stools; in addition to the predominant GI sx and malaise, pts become icteric and may develop RUQ pain with hepatomegaly Phase 4 (convalescent phase)- sx and icterus resolve, liver enzymes return to nl ```

Question 40

Hx of Hep A

Answer 40

``` Incubation period 2-7 wks Presentation similar to that of gastroenteritis or a viral respiratory infection MC s/sx: Fatigue Nausea Vomiting Fever Hepatomegaly Jaundice Dark urine Anorexia Rash ```

Question 41

Hx of Hep B

Answer 41

Incubation: 30-180 days Prodromal phase, characterized by gradual onset of anorexia, malaise, and fatigue. Pt may experience RUQ pain during this time Icteric phase: jaundice develops Urine darkens and stools lighten in color May have nausea, vomiting, and pruritis

Question 42

Hx of Hep C

Answer 42

Incubation: 15-150 days Sx may appear similar to those of HBV infection In up to 80% of cases, pts are asymptomatic

Question 43

PE of hepatitis

Answer 43

PE findings vary with the type of hepatitis and time of presentation Often present with low-grade fever Those experiencing sig vomiting and anorexia may show signs of dehydration Icteric phase: may have icterus of the sclerae or mucous membranes or discoloration of the TMs Skin may be jaundiced and may reveal macular, papular, or urticarial rashes Liver may be tender and diffusely enlarged with a firm, sharp, smooth edge

Question 44

Workup for hepatitis: hep A

Answer 44

Acute infection: IgM antibody to hep A virus anti-HAV

Question 45

Workup for hepatitis: hep B

Answer 45

HBsAg is the first serum marker seen in persons with acute infection HBeAg is also present until viral replication slows, then replaced with anti-HBe First antibody to appear is HBcAg anti-HBc, of the IgM class

Question 46

Workup for hepatitis: hep C

Answer 46

Elevated AST and ALT Hep C serology HCV RNA testing

Question 47

Tx of acute hepatitis

Answer 47

Hep A: Supportive tx, hospitalization whose nausea and vomiting places them at risk for dehydration Hep B: Mostly supportive Hep C: Early interferon therapy should be considered