1. What signs or symptoms suggest intestinal obstruction in the neonate?

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Signs and symptoms vary according to the level of obstruction. Proximal intestinal obstruction leads to the early onset of bilious emesis, generally with minimal abdominal distention. In contrast, neonates with distal intestinal obstruction present after the first day of life with bilious vomiting and pronounced abdominal distention. Bilious emesis should always be interrogated further in infants and children.

2. What is the differential diagnosis of intestinal obstruction in neonates?

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Look for an anal opening, which eliminates the diagnosis of imperforate anus. Next obtain an abdominal radiograph. The extent of gaseous distention of the bowel implicates a proximal or distal bowel obstruction. No attempts should be made to distinguish small from large bowel obstruction.

3. When are contrast studies of the gastrointestinal (GI) tract indicated? Show answer
If peritonitis or pneumoperitoneum is present, proceed to exploratory laparotomy without delay. Malrotation with volvulus must be distinguished from the other cause of congenital duodenal obstruction (duodenal atresia). In this setting, upper GI is the study of choice. In volvulus, the upper GI demonstrates distention of the proximal duodenum, corkscrewing of the distal duodenum, and limited or no progression of contrast into the distal bowel. Conversely, duodenal atresia appears as a blind ending pouch in the first or second portion of the duodenum. Contrast enema is generally the preferred study in all other forms of neonatal intestinal obstruction.

4. Describe intestinal atresia.

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Atresia can occur anywhere in the GI tract: duodenal (50%), jejunoileal (45%), or colonic (5%). Duodenal atresia arises from a failure of recanalization during the 8th-10th week of gestation; jejunoileal and colonic atresia are caused by an in utero mesenteric vascular accident.

5. Distinguish duodenal atresia from other forms of intestinal atresia.

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Duodenal atresia is characterized by the onset of bilious vomiting (85% of atresia distal to the ampulla of Vater) within the first day of life; significant abdominal distention is absent. Approximately 25% of affected infants have trisomy 21. The abdominal radiograph demonstates a “double bubble” caused by the distended stomach and first or second portions of duodenum. Surgical correction is performed by duodenoduodenostomy.
Jejunoileal atresia produces bilious vomiting at 2-3 days of life with moderate to severe abdominal distention. The abdominal radiograph shows dilated loops of bowel with air-fluid levels. Barium enema reveals a microcolon and no reflux of contrast into the dilated bowel. Associated anomalies are uncommon. Surgical correction involves end-to-end anastomosis with or without limited intestinal resection.
Colonic atresia, similar to jejunalileal atresia, is associated with the late onset of bilious vomiting, no passage of meconium, and moderate to severe abdominal distention. The abdominal radiograph reveals dilated loops of bowel with air-fluid levels suggesting distal intestinal obstruction. Barium enema demonstrates a microcolon with a cutoff observed in a proximal colonic segment. Twenty percent of affected infants suffer an associated anomaly of the heart, musculoskeletal system, abdominal wall, or GI tract. Surgical management includes limited colonic resection with primary anastomosis.

6. Describe malrotation with midgut volvulus.

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During the 6th-12th week of gestation, the intestine undergoes evisceration, growth, return to the abdominal cavity, and counterclockwise rotation with fixation. Malrotation is an error in both rotation and fixation. Abnormal fixation and a narrow-based mesentery predispose to twisting of the midgut on its blood supply (superior mesenteric artery), vascular occlusion (strangulation), and obstruction (malrotation with midgut volvulus). Typically, a previously well neonate or child without a history of surgery presents with bilious vomiting, abdominal distention, and variable degrees of shock. If the infant is acutely ill, no further studies are needed and surgical exploration is indicated. If the diagnosis is in question and the infant is stable, an upper GI study, not a barium enema, is performed. Surgical treatment entails four parts: (1) division of abnormal peritoneal bands, (2) correction of malrotation, (3) restoration of a broad-based mesentery, and (4) appendectomy because of the location of the cecum in the right upper quadrant.

7. Is midgut volvulus a surgical emergency?

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Yes! The risk of strangulation caused by the rotational anomaly and abnormal peritoneal bands implies a surgical emergency. Delay places the infant at risk of losing the entire midgut and potentially dying.

8. What is meconium ileus (MI)?

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MI is the obstruction of the terminal ileum by highly viscid, tenacious meconium. MI is a complication of cystic fibrosis (CF). Fifteen percent of neonates with CF present with MI. The combination of hyperviscous mucus secreted by the abnormal intestinal glands and pancreatic insufficiency leads to abnormal meconium and obstructs the lumen of the terminal ileum. Symptoms of feeding intolerance, bilious emesis, and abdominal distention begin in the second to third days of life. Unlike most forms of neonatal intestinal obstruction, surgery is reserved for patients refractory to nonoperative treatment or complex MI (atresia, volvulus, perforation). Sixty percent of infants with simple MI can be treated successfully with Gastrografin enemas and rectal irrigation. If an operation is indicated, the objective is to remove the obstructing meconium by limited resection or enterostomy with evacuation of the meconium and irrigation of the distal bowel.

9. What is Hirschsprung’s disease?

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In this disease, the intestine is innervated by cells originating in the neural crest. During the 5th-12th week of gestation, neural crest cells migrate in a craniocaudal direction and disperse within the wall of the intestine (intermuscular, to Auerbach’s plexus; submucosal, to Meissner’s plexus). Hirschsprung’s disease arises from the failure of normal enteric innervation. The bowel remains in a contracted, spastic state and produces a functional rather than a true mechanical obstruction. Abdominal distention, feeding intolerance, and delayed or absent meconium within the first 48 hours of life are the presenting findings in infants. Older patients suffer chronic constipation, abdominal distention, and failure to thrive. Because the disease always affects the most distal bowel (80-85% rectosigmoid) with a variable involvement of proximal bowel, barium enema demonstrates the characteristic radiographic appearance of a spastic, contracted rectum with dilated proximal bowel. Suction rectal biopsy documenting the absence of ganglion cells and presence of nerve hypertrophy confirms the diagnosis. Surgical correction is performed by excision of the aganglionic (distal colorectal) segment and coloanal anastomosis.

10. What is intussusception? What are the therapeutic options?

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Intussusception is the invagination of proximal bowel (intussusceptum) into the distal bowel (intussuscipien). Swelling, vascular compromise, and obstruction follow. Nearly two thirds of cases occur in the first 2 years of life. The cause is thought to be a result of lymphoid hyperplasia in the terminal ileum after viral infection. The diagnosis should be suspected in previously well infants, 6-9 months of age, with vomiting, crampy abdominal pain, and bloody stools. Barium or air enema is both diagnostic and therapeutic. Injection of contrast demonstrates colonic obstruction with no reflux into the proximal bowel. Controlled hydrostatic reduction with barium or air is successful in 90% of cases. If hydrostatic reduction is unsuccessful or in children with peritonitis, operative reduction is indicated. The risk of recurrent intussusception is 5% for either radiographic or surgical reduction.

11. What examples of neonatal obstruction can escape early detection and present later in life?

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Although most conditions are identified within the first week to month of life, lesions other than atresia may be identified in children and even adults.
Duodenal stenosis. Unlike duodenal atresia, stenosis results in narrowing but not complete obstruction of the duodenum. Thus, infants fed formula or pureed foods may not become symptomatic until childhood. Children with intermittent abdominal pain and symptoms of gastric outlet obstruction require an upper GI study, particularly if they have trisomy 21.
Malrotation. One third of patients with malrotation are identified after the first month of life. Children present with bilious emesis and intermittent abdominal pain, and malrotation is generally identified by an upper GI series. Malrotation with midgut volvulus should be suspected in any ill child with signs of intestinal obstruction and no history of abdominal surgery.
Hirschsprung’s disease. One third of patients are diagnosed after the first year of life. A long history of constipation refractory to therapy mandates rectal biopsy, particularly in patients with trisomy 21.
Intussusception. One third of cases occur after age 2 years. A pathologic lead point (i.e., polyp, tumor, hematoma, Meckel’s diverticulum) is present in one third of older patients.

References
BIBLIOGRAPHY
1. Aquino A, Domini M, Rossi C, et al: Correlation between Down’s syndrome and malformation of pediatric surgical interest. J Pediatr Surg 33:1380-1382, 1998. Medline Similar articles
2. Daneman A, Alton DJ, Ein S, et al: Perforation during attempted intussusception reduction in children-a comparison of perforation with barium and air. Pediatr Radiol 25:81-88, 1995. Medline Similar articles
3. Godbole P, Stringer MD: Bilious vomiting in the newborn: How often is it pathologic? J Pediatr Surg 37:909-911, 2002.
4. Long FR, Kramer SS, Markowitz RI, Taylor GE: Radiographic patterns of intestinal malrotation in children. Radiographics 16:547-560, 1996. Medline Similar articles
5. Maxson RT, Franklin PA, Wagner CW: Malrotation in the older child: Surgical management, treatment, and outcome. Am Surg 61:135-138, 1995. Medline Similar articles
6. Reding R, de Ville de Goyet J, Gosseye S, et al: Hirschsprung’s disease: A 20 year experience. J Pediatr Surg 32:1221-1225, 1997. Full article

1. What are the top three causes of cancer deaths in the United States?

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Lung, breast or prostate, and colon cancer.

2. List a few of the presenting symptoms of patients with colorectal cancer.

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Intermittent rectal bleeding, vague abdominal pain, fatigue secondary to anemia, change in bowel habits, constipation, tenesmus, and perineal pain.

3. What options are available to evaluate a patient who has guaiac-positive stools?

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To evaluate the entire colon and rectum, one may perform a barium enema and proctoscopy or a colonoscopy. Colonoscopy is 10 times more expensive but is more sensitive for lesions < 1 cm.

4. List at least five risk factors for colorectal cancer.

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Prior adenomatous polyps, family history of colorectal cancer, age older than 40 years, chronic ulcerative colitis, Crohn’s colitis, history of colon cancer, exposure to pelvic radiation for prostate or cervical cancer, and familial polyposis. Hamartomatous polyps (Peutz-Jeghers syndrome), inflammatory polyps, and hyperplastic polyps are not considered premalignant.

5. What are the current screening recommendations of the American Cancer Society for colorectal cancers?

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A yearly digital rectal examination with testing for occult blood for patients age 40 years and older. Additionally, for patients older than age 50 years, a flexible sigmoidoscopy is recommended every 3-5 years.

6. In what part of the colon or rectum are most cancers found?

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Historically, there has been a higher incidence of cancers in the rectum and left colon. However, over the past 50 years, there has been a gradual shift toward an increased incidence of right colon cancers. This change in pattern may reflect improvement in early detection.

7. Surgical options for colorectal cancer are dependent on the tumor location. What operation should be performed for a patient with a lesion at 25 cm from the anal verge?

Show answer
A sigmoid colectomy.
8. What about a lesion at 9 cm from the anal verge? Show answer
A low anterior resection (LAR).
9. What about a lesion at 4 cm from the anal verge? Show answer
An abdominoperineal resection (APR). This requires a permanent colostomy.

10. What is the significance of finding adenomatous polyps in a patient’s colon?

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KEY POINTS: COLORECTAL CARCINOMA

1. Presenting symptoms may include intermittent rectal bleeding, vague abdominal pain, fatigue secondary to anemia, change in bowel habits, constipation, tenesmus, and perineal pain.
2. The current recommendations of the American Cancer Society for screening are a yearly digital rectal exam with testing for occult blood at age 40 years and for patients over 50 a flexible sigmoidoscopy every 3-5 years.
3. Patients with lymph node involvement should receive chemotherapy postoperatively to treat micrometastases.

This patient is six times more likely to develop colorectal cancer than a patient without polyps. Evidence suggests that all colon cancers arise from adenomatous polyps. The “adenoma-carcinoma sequence” describes this transformational process. Patients with familial adenomatous polyposis (FAP) typically harbor more than 100 polyps, which cover the colonic mucosa. If these patients go untreated, they will, without exception, develop adenocarcinoma of the colon by age 40 years.

11. How does the surgeon prepare the patient’s colon for an operation?

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Bowel preparation includes both a mechanical cleansing and appropriate antimicrobial prophylaxis. This combination has resulted in significant decrease in morbidity and mortality from colon surgery. Mechanical cleansing can be accomplished by lavage with polyethylene glycol (Go-Lytely) or a combination of cathartics and enemas (Fleet’s Prep).
Antimicrobial prophylaxis should cover the expected aerobic and anaerobic flora of the gut. Significant controversy exits over whether the antibiotics should be given enterally (e.g., neomycin, 1 g, and metronidazole [Flagyl], 1 g, three times orally at 4-hour intervals the evening before surgery) or parenterally (e.g., cefotetan, 2 g intravenously within 1 hour before surgery). Many clinicians give both to obtain both intraluminal and systemic protection.

12. What is Dukes’ staging system?

Dukes A – Tumor confined to bowel wall
Dukes B – Tumor invading through the bowel wall
Dukes C – Tumor cells found in the regional lymph nodes

In 1932, Dr. Dukes described a staging system for rectal cancer. He originally described the following: Since his original article was published, this classification has been modified several times. One of the most commonly used modifications is the inclusion of Dukes’ D stage, which indicates distant metastases.

13. Which patients with colorectal cancer require adjuvant (postoperative) therapy?

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Patients with lymph node involvement (Dukes’ C) should receive chemotherapy postoperatively to treat micrometastases. Two large studies have documented a survival advantage for these patients. However, no studies have documented a survival advantage for patients with Dukes’ B disease treated with chemotherapy.
Patients with rectal cancer with a significant chance of local recurrence (Dukes’ B and C) should be treated with radiation therapy. This may be given preoperatively, postoperatively, or with a combined “sandwich” technique.

References
WEB SITE
http://www.nejm.org
BIBLIOGRAPHY
1. Colorectal Cancer Collaborative Group: Adjuvant radiotherapy for rectal cancer: A systematic overview of 22 randomised trials involving 8507 patients. Lancet 358:1291-1304, 2001.
2. Jass JR: Pathogenesis of colorectal cancer. Surg Clin North Am 82:891-904, 2002. Medline Similar articles
3. Levin B, Brooks D, Smith RA, Stone A: Emerging technologies in screening for colorectal cancer: CT colonography, immunochemical fecal occult blood tests, and stool screening using molecular markers. CA Cancer J Clin 53:44-55, 2003. Medline Similar articles
4. Lynch HT, de la Chapelle A: Hereditary colorectal cancer. N Engl J Med 348:919-932, 2003. Medline Similar articles
5. National Institutes of Health Consensus Conference: Adjuvant therapy for patients with colon and rectal cancer. JAMA 264:1444-1450, 1990.
6. Ransohoff DF: Screening colonoscopy in balance issues of implementation. Gastroenterol Clin North Am 31:1031-1044, 2002. Medline Similar articles
7. Salz LB, Minsky B: Adjuvant therapy of cancers of the colon and rectum. Surg Clin North Am 82:1035-1058, 2002.
8. US Multisociety Task Force on Colorectal Cancer: Colorectal cancer screening and surveillance: Clinical guidelines and rationale-update based on new evidence. Gastroenterology 124:544-560, 2003.

1. What is the surgeon’s responsibility when confronted by a patient with an acute abdomen?

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1. To identify how sick the patient is
2. To determine whether the patient (a) needs to go directly to the operating room, (b) should be admitted for resuscitation or observation, or (c) can be sent safely home

2. Which is the most dangerous course?

Show answer
To send the patient home.

3. Is it important to make the diagnosis in the emergency department?

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No. Frequently time spent confirming a diagnosis in the emergency department is lost to inhospital resuscitation or treatment in the operating room. The only patient who needs a relatively firm diagnosis is a patient who is to be sent home.

4. If the essential goal is not to make the diagnosis, what should the surgeon do?

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1. Resuscitate the patient. Most patients do not eat or drink when they are getting sick. Most patients are depleted of at least several liters of fluid. Fluid depletion is worse in patients with diarrhea or vomiting.
2. Start a big IV line.
3. Replace lost electrolytes (see Chapter 7).
4. Insert a Foley catheter.
5. Examine the patient (frequently).

5. Are symptoms and signs uniquely misleading in any groups of patients?

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Yes. Watch out for the following groups:

* The very young, who cannot talk.
* Diabetics, because of visceral neuropathy.
* The very old, in whom, much as in diabetics, abdominal innervation is dulled.
* Patients taking steroids, which depress inflammation and mask everything.
* Patients with immunosuppression (a heart or kidney transplant patient may act cheerful even with dead or gangrenous bowel).

6. Summarize the history needed.

Show answer

1. The patient’s age. Neonates present with intussusception; young women present with ectopic pregnancy, pelvic inflammatory disease, and appendicitis; the elderly present with colon cancer, diverticulitis, and appendicitis.
2. Associated problems. Previous hospitalizations, prior abdominal surgery, medications, heart and lung disease? An extensive gynecologic history is valuable; however, it is probably safer to assume that all women between 12 and 40 years old are pregnant.
3. Location of abdominal pain. Right upper quadrant: gallbladder or biliary disease, duodenal ulcer. Right flank: pyelonephritis, hepatitis. Midepigastrium: duodenal or gastric ulcer, pancreatitis, gastritis. Left upper quadrant: ruptured spleen, subdiaphragmatic abscess. Right lower quadrant: appendicitis (see Chapter 37), ectopic pregnancy, incarcerated hernia, rectus hematoma. Left lower quadrant: diverticulitis, incarcerated hernia, rectus hematoma. Note: Cancer, unless it obstructs (colon cancer), and bleeding (diverticulosis) typically do not hurt.
4. Duration of pain. The pain of a perforated duodenal ulcer or perforated sigmoid diverticulum is sudden, whereas the pain of pyelonephritis is gradual and persistent. The pain of intestinal obstruction is intermittent and crampy. Note: Although the surgeon is rotating through a gastrointestinal service, the patient may not know this and may present with urologic, gynecologic, or vascular pathology.

15. How is a complete blood count helpful?

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1. Hematocrit. If the hematocrit is high (> 45%), the patient is most likely dry or may have chronic obstructive pulmonary disease. If it is low (< 30%), the patient probably has a more chronic disease (associated with blood loss-always do a rectal and test the stool for blood).
2. White blood cell count. It takes hours for inflammation to release cytokines and elevate the white blood cell count. A normal white blood cell count is entirely consistent with significant abdominal trouble.

16. Is urinalysis necessary?

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Yes. White blood cells in the urine may redirect attention to the diagnosis of pyelonephritis or cystitis. Hematuria points to renal or ureteral stones. Because an inflamed appendix may lie directly on the right ureter, red and white blood cells may be found in the urine of patients with appendicitis.

17. What is a “three-way of the abdomen”?

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1. Upright chest radiograph. Look for free air under the diaphragm (perforated viscus) and pneumonia or pneumothorax.
2. Upright abdomen. Look for free air under the diaphragm and air-fluid levels (intestinal obstruction). Remember to look for sigmoid or rectal air (partial obstruction).
3. Supine abdomen. This radiograph tells nothing.

Most ureteral stones can be visualized. Only 10% of gallstones are radiopaque, and appendiceal fecaliths are rarely noted.
Honors: Air in the biliary system indicates a biliary-enteric fistula; this in association with intestinal air-fluid levels makes the diagnosis of gallstone ileus.
KEY POINTS: RADIOGRAPHIC EVALUATION FOR THE ACUTE ADBOMEN

1. May assist in diagnostic evaluation but should not supplant physical exam in evaluaton of an acute abdomen.
2. Three-way of the abdomen: look for free air under the diaphragm, intrathoracic pathology, air-fluid levels, dilated alimentary canal, distal air in rectum.
3. Ultrasound: useful for biliary, ob-gyn, and vascular assessments; may note intraperitoneal or retroperitoneal fluid collections.
4. Computed tomography: increasing use in clinical arena, with excellent visualization of abdominal structures. Drawbacks: cost, radiation exposure.

18. What is a sentinel loop?

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Except in children (who swallow everything, including air), small bowel gas is always pathologic. A single loop of small bowel gas adjacent to an inflamed organ (e.g., the pancreas) may point to the diseased organ.

19. Is ultrasound valuable?

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Yes, if the working diagnosis is cholecystitis, gallstones, ectopic pregnancy, ovarian cyst, abdominal aortic aneurysm, or intraperitoneal/retroperitoneal fluid.

20. Is abdominal computed tomography (CT) valuable?

Show answer
Yes, if the working diagnosis is an intra-abdominal abscess (sigmoid diverticulitis), pancreatitis, retroperitoneal bleeding (leaking abdominal aortic aneurysm; this patient should have gone straight to the operating room), or intrahepatic or splenic pathology.

21. What is a double-contrast CT scan?

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The bowel is delineated with barium or Gastrografin. The blood vessels are delineated with an iodinated vascular dye. The CT scan precisely displays the abdominal contents relative to vascular and intestinal landmarks. Contrast CT of pancreatitis is valuable to assess zones of perfusion or necrosis.

1. What two clinical entities encompass the diagnosis of inflammatory bowel disease?

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Crohn’s disease and ulcerative colitis (acute or chronic).

2. Although the two diseases often overlap, they usually can be distinguished by clinical criteria. What are the major clinical differences?

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Rectal bleeding is unusual in Crohn’s disease but common in chronic ulcerative colitis. An abdominal mass and anal complications (fissure, fistula) are more common in Crohn’s disease.

3. What are the major radiologic differences between the two diseases?

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Terminal ileal involvement, skip areas, internal fistulas, and “thumb printing” are rare or absent in chronic ulcerative colitis but common in Crohn’s disease.

4. What are the major histologic differences?

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Granulomas in the intestinal wall and adjacent lymph nodes are absent in ulcerative colitis but occur in 60% of patients with Crohn’s disease. The inflammatory process in Crohn’s disease involves the entire bowel wall. In ulcerative colitis, the inflammation usually is limited to the mucosa and submucosa.

5. Although Crohn’s disease may affect the gastrointestinal (GI) tract from the pharynx to the anus, what are the most common clinical patterns of GI involvement?

Show answer
Small bowel only: 28%; both ileum and colon (ileocolitis): 41%; and colon only: 27%. Crohn’s involvement of the colon is also called Crohn’s colitis or granulomatous colitis.

6. Crohn’s colitis and ulcerative colitis are often difficult to distinguish clinically. What are the major differences at colonoscopy?

Show answer
Crohn’s disease is focal and predominantly right sided. The mucosa has a cobblestone appearance with transverse ulcerations in affected areas. Biopsies reveal transmural disease with possible focal granulomas. On colonoscopy, chronic ulcerative colitis may appear as a diffuse disease. However, if only a portion of the colon is involved, it is on the left side and almost always involves the rectum. Pathologic changes involve the mucosa and submucosa.

7. What are the major indications for surgery in Crohn’s disease?

Show answer
It depends on the site of involvement. Enterocutaneous or enteroenteral fistulas (controversial), abscess, and intestinal obstruction are the most common surgical indications for small intestinal and ileocolic types. Perianal disease, medical failure, ileocolic fistulas, and abscess formation are the most common indicators for surgery in Crohn’s colitis.

8. What are the major indications for surgery in ulcerative colitis?

Show answer
Medical intractability (including failure to thrive in children, diarrhea, weight loss, and abdominal pain), toxic megacolon with or without perforation, and concern about the development of colonic cancer (controversial, but real).

KEY POINTS: DIFFERENCES BETWEEN CROHN’S DISEASE AND ULCERATIVE COLITIS

1. Rectal bleeding is uncommon in Crohn’s disease but common in chronic ulcerative colitis.
2. Terminal ileal involvement, skip areas, internal fistulas, and “thumb printing” are common in Crohn’s disease but rare or absent in chronic ulcerative colitis.
3. In ulcerative colitis, the inflammation is usually limited to the mucosa and submucosa, whereas in Crohn’s disease it involves the entire bowel wall.

9. What is the surgical treatment of ulcerative colitis?

Show answer
Total colectomy with ileoanal pouch anastomosis is the standard. A total colectomy with a Brooke ileostomy was the classic surgical approach and is still applicable in some situations. A Kock (continent) pouch can be used for younger (age < 55 years) patients who do not wish to wear an ileostomy bag or who have lost their ileoanal pouch. Ileorectal anastomosis has been advocated by some (controversial), but this leaves disease behind.

10. What are the surgical procedures for the complications of Crohn’s disease?

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Complications requiring surgery are usually corrected by removing all areas of bowel involved in the complication. Strictureplasty as opposed to resection is now preferred in selected cases of small bowel obstruction. When resection is necessary, grossly clear margins are satisfactory. Skip areas should be preserved unless they are directly adjacent to resected intestine.

11. What should the patient be told about the possibility of recurrence after surgery?

Show answer
With chronic ulcerative colitis, surgery is definitive and curative. With Crohn’s disease, however, the aim of surgery is to treat the complications (i.e., obstruction and sepsis). Recurrence of Crohn’s disease can be expected in a high percentage of cases if the patient is followed long enough. Small bowel recurrence after total colectomy for Crohn’s colitis does occur.

12. How do you evaluate the placement of a stoma?

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The location of a stoma is a major factor in patient morbidity. Placement is optimal at the summit of the infraumbilical bulge within the rectus muscle. This is usually within a triangle formed by lines between the umbilicus to the anterior superior iliac spine, umbilicus to the pubis, and the inguinal ligament. All scars and creases should be avoided.

13. Does Crohn’s disease have a genetic basis?

Show answer
The patients described by Crohn et al. in the original article were a 14-year-old boy and his 32-year-old sister. Genetic studies have identified two loci, IBD1 and IBD2 on chromosomes 16 and 12, respectively, that are linked to inflammatory bowel disease. New data suggest that these mutations affect the innate bacterial reaction to lipopolysaccharides, leading to an exaggerated immune response, causing the tissue damage in Crohn’s disease. Similar studies also have links to chromosomes 14q and 6p.

14. What is the difference between an enteroclysis and a small bowel follow-through?

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Enteroclysis is a procedure performed by a radiologist with a catheter placed at the duodenal-jejunal junction. Because the rate of barium entering the intestine and thus distention of the intestine can be controlled, this study provides a superior demonstration of the luminal contour, valvulae conniventes, and mucosal surface. Thus, it is superior to the small bowel follow-through for the evaluation of short obstructing lesions but is a technically more demanding procedure for the radiologist and the patient.

15. What is a Brooke ileostomy?

Show answer
The Brooke ileostomy is the “rosebud” or full-thickness ileostomy folded over on itself for approximately 1 cm above the skin. This prevents the erosion of the skin and high-output serositis that is common with an ostomy that is flush with the skin.

16. What is pouchitis, and which patients are likely to have it?

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Pouchitis is an inflammation of indeterminate origin, possibly related to bacterial overgrowth, that occurs in the ileal pouch after ileal-pouch anal anastomosis. This complication is common (25%) when this procedure is performed for ulcerative colitis, but it is rare when this same procedure is performed for familial polyposis. Patients with pouchitis are effectively treated with metronidazole, ciprofloxacin, or 5-amino salicylic acid. They rarely require ileal diversion or pouch excision.

1. What is upper gastrointestinal (GI) bleeding?

Show answer
Bleeding from proximal to the ligament of Treitz (the transition point between duodenum and jejunum).

2. What are the most common causes of upper GI bleeding?

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In descending order of frequency, they are gastritis, duodenal ulcer, esophageal varices, benign gastric ulcer, esophagitis, and Mallory-Weiss tear. All other causes account for < 5% of cases.

3. What is the overall mortality rate of upper GI bleeding?

Show answer
Approximately 10%. Mortality is usually associated with comorbid factors such as cardiac, pulmonary, hepatic, and renal disease as well as age (> 60 years) and large transfusion requirements (> 5 units of blood). Patients who rebleed during the same hospitalization have a mortality rate of 30%.

4. What is the most common presentation of upper GI bleeding?

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Eighty percent of patients present with melena (blood is a cathartic, and patients pass black, tarry, or maroon-colored stools) or hematochezia (bright red blood in the rectum). Hematemesis (bright red or coffee-ground emesis) is diagnostic of an upper source of GI bleeding. Occult bleeding may present only with guaiac-positive stool.

5. How much GI blood loss is necessary to cause melena?

Show answer
As little as 50 mL. Occult bleeding (guaiac- or Hematest-positive) can be detected with as little as 10 mL of blood loss.

6. A 45-year-old man presents to the emergency department with massive hematemesis, tachycardia, and hypotension. What should the initial approach be?

Show answer
Acute GI hemorrhage requires a prompt and systematic approach. As in all critically ill patients, initially assess the ABCs (airway, breathing, circulation). Start two large-bore intravenous (IV) lines, and give 1 L of Ringer’s lactate while monitoring the patient. Place a nasogastric tube (NGT) and Foley catheter and irrigate the NGT with saline. Send blood for type and crossmatch and coagulation and liver function tests.

7. This patient stabilizes after your interventions. Is a medical history of any value in determining a cause of the bleeding?

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Yes. The following are pertinent:

* Previous symptoms of peptic ulcer disease or nonsteroidal anti-inflammatory drug use: bleeding duodenal or gastric ulcer
* History of gastroesophageal reflux disease: esophagitis
* Heavy alcohol use: gastritis or bleeding varices
* Recent retching or vomiting: Mallory-Weiss tear
* Weight loss: upper GI malignancy

8. What physical finding may be helpful in establishing the source of bleeding?

Show answer
Physical examination is generally not helpful. The stigmata of liver disease (jaundice, caput medusa, ascites, muscle wasting) raise the suspicion of variceal bleeding or multiple superficial gastric erosions.

9. What percentage of patients with known esophageal varices are bleeding from the varices on presentation?

Show answer
Only 50%.

10. Does bilious or clear NGT aspirate rule out an upper GI source of hemorrhage?

Show answer
No. Although NGT aspiration can be useful in directing the search for a bleeding site, one should keep in mind that the false-negative rate may be as high as 20%.

11. What studies can be used to determine the source of bleeding?

Show answer
Esophagogastroduodenoscopy (EGD) is the first and best test. Barium studies may miss a significant source of upper GI bleeding, such as erosive gastritis, and interfere with other more definitive tests, especially arteriography. Nuclear scans are of limited value in acute upper GI hemorrhage.

12. What is the sensitivity of EGD?

Show answer
EGD identifies the source of bleeding in up to 95% of cases. EGD has the advantage of directly visualizing the source of blood loss and provides the opportunity to biopsy a lesion and perform therapeutic maneuvers such as cauterizing a bleeder in a duodenal ulcer.
KEY POINTS: UPPER GI BLEEDING

1. Upper GI bleeding is defined as bleeding proximal to the ligament of Treitz.
2. The most common causes are gastritis, duodenal ulcer, esophageal varices, benign gastric ulcer, esophagitis, and Mallory-Weiss tear.
3. Eight percent of patients present with melena or hematochezia.
4. EGD identifies the source of bleeding in 95% of cases.

13. How can EGD be used to control nonvariceal bleeding?

Show answer
Electrocautery and injection of vasoconstrictors are well-established techniques. Other modalities such as argon beam coagulation, hemoclips, and cyanoacrylates (super glue) are promising.

14. What amount of bleeding is required to see a “blush” on arteriography?

Show answer
Less than 5 mL per minute. Although angiography is the most invasive of these tests, the catheter can be left in place and used for delivery of therapeutic vasopressin or embolization.

15. What treatment options are available to control variceal bleeding?

Show answer
Upper endoscopy with sclerotherapy or band ligation. In experienced hands, placement of a Sengstaken-Blakemore tube (a double balloon tube that permits direct tamponade of both gastric and esophageal varices) temporarily controls bleeding in 90% of cases. IV infusion of vasopressin or octreotide should decrease blood flow to the varices but is less successful in patients with more severe liver disease.

16. What are the indications for surgery in patients with upper GI hemorrhage?

Show answer
About 10% of patients eventually require surgery. Indications include:

* Persistent hypotension or shock (failure of resuscitative therapy)
* Recurrent bleeding while on maximal medical therapy
* High-risk patients with significant comorbid disease
* Large transfusion requirements (transfusion of more than two thirds of the patient’s blood volume in 24 hours)

17. What is the surgical approach to an unstable patient with a nonlocalized upper GI bleed who does not respond to initial resuscitation?

Show answer
At laporotomy start with a generous gastroduodenotomy centered over the pylorus. If this does not reveal a source of bleeding, proceed with a proximal gastrotomy.

18. A patient presents with hematemesis and has a remote history of an abdominal aortic aneurysm repair. What uncommon cause of upper GI bleeding needs to be considered?

Show answer
Aortoduodenal fistula. Any patient with a history of aortic surgery and evidence of GI bleeding should be aggressively worked up for aortoenteric fistula. The study of choice is endoscopy.

19. What is a Dieulafoy’s ulcer?

Show answer
A gastric vascular malformation with an exposed submucosal artery, usually within 2-5 cm of the gastroesophageal junction. It presents with painless hematemesis, often massive (fortunately, this is uncommon).

20. A patient recently admitted with a traumatic liver laceration is treated nonoperatively and later develops painless hematemesis. What do you suspect? How should you treat this patient?

Show answer
Hemobilia, another rare cause of upper GI bleeding, usually occurs after liver trauma or hepatic resection. Treatment consists of angiographic embolization.

21. What are other rare causes of upper GI bleeding?

Show answer
Watermelon stomach, portal hypertensive gastropathy, arteriovenous malformations, upper GI neoplasm, duodenal diverticulum, and pancreatitis (resulting in erosion into the splenic artery or splenic vein thrombosis with portal hypertension).

References
BIBLIOGRAPHY
1. Cameron JL: Current Surgical Therapy, 7th ed. St. Louis, Mosby, 2001.
2. Conrad SA: Acute upper gastrointestinal bleeding in critically ill patients: Causes and treatment modalities. Crit Care Med 30:365-368, 2002.
3. Fallah MA, Prakash C, Edmundowitz S: Acute gastrointestinal bleeding. Med Clin North Am 84:1183-1208, 2000. Medline Similar articles
4. Jamieson GG: Current status of indications for surgery in peptic ulcer disease. World J Surg 24:256, 2000. Medline Similar articles
5. Savides TJ, Jensen DM: Therapeutic endoscopy for nonvariceal gastrointestinal bleeding. Gastroenterol Clin North Am 29:465-487, 2000. Medline Similar articles

1. Why are penetrating neck wounds unique?

Show answer
Although comprising only a small percentage of body surface area, the neck contains a heavy concentration of vital structures.

2. What constitutes a penetrating neck wound?

Show answer
Violation of the platysma muscle defines a penetrating neck wound. This investing fascial layer of the neck is superficial to vital structures. If the platysma is not penetrated, the wound is managed as a simple laceration.

3. Identify the boundaries of the three zones of the neck.

Show answer
Zone I extends from the sternal notch to the cricoid cartilage.
Zone II extends from the cricoid cartilage to the angle of the mandible.
Zone III comprises the area cephalad to the angle of the mandible.
These zones have distinct management implications.

4. Which side of the neck is more likely to be injured?

Show answer
The left side because most assailants are right-handed.

5. Do gunshot wounds and knife wounds cause the same relative injuries?

Show answer
Gunshot wounds generally tend to inflict more tissue damage (see Table 20-1).
Table 20-1. GUNSHOT VERSUS TAB WOUNDS

6. What are the priorities in the management of penetrating neck trauma?

Show answer
The ABCs (airway, breathing, and circulation) are the first priority in every trauma patient. Patients should be intubated orally, although cricothyrotomy may be necessary with an extensive neck wound. Although the patient may present with a patent airway, early elective airway control is advisable in patients with expanding hematomas. Pneumothoraces or hemothoraces may be associated with these injuries depending on the trajectory. While hemorrhage is being controlled with direct pressure, IV access is secured with two large-bore peripheral lines.

7. How should bleeding be controlled at the accident scene and in the emergency department?

Show answer
Direct pressure is nearly always successful, even for major arterial lesions. Do not blindly place clamps because the risk of injury to vital structures is high.

8. Should you explore the wound in the trauma bay?

Show answer
Only if the patient is asymptomatic and there has been no evidence of hemorrhage. Probing the wound may dislodge a clot, causing marked hemorrhage.

9. What physical signs are consistent with significant injury?

Show answer
Ongoing hemorrhage from the wound, expanding or pulsatile hematoma, hemoptysis, hematemesis, neurologic deficits, dysphagia, dysphonia, hoarseness, and stridor mandate an early trip to the operating room.

10. How often do patients with crepitus (in the neck) have a significant injury?

Show answer
One third of patients with crepitus have an injury of the pharynx, esophagus, larynx, or trachea. In two thirds of these patients, however, the air has been introduced through the wound entrance site, and there is no significant underlying injury.

11. What is selective management of penetrating neck trauma?

Show answer
Previously, operative exploration was advocated for all zone II injuries violating the platysma; this approach has lost support. With 50% of penetrating neck wounds not associated with significant injury, exploration is not mandatory. Alert and asymptomatic patients are evaluated with a combination of diagnostic studies (see later) or are observed expectantly with frequent serial physical examinations.

KEY POINTS: SELECTIVE MANAGEMENT OF PENETRATING INJURIES TO ZONE II

1. Penetrating injury implies violation of the platysma.
2. Mandatory exploration of all zone II injuries is not necessary since 50% of wounds are not associated with significant injury.
3. Alert and asymptomatic patients should be observed expectantly for at least 24 hours.
4. Symptomatic patients (exsanguinations or expanding hematoma) proceed to the operating room for exploration.
5. Aerodigestive symptoms (e.g., stridor, dysphonia) mandate further diagnostic testing: laryngoscopy, bronchoscopy, and esophagram.

12. Should arteriography be performed on all patients?

Show answer
Preoperative arteriograms generally are performed in hemodynamically stable patients with zone I injuries. Their value is to identify injuries to major vessels in the thoracic outlet that may require a thoracic operative approach. Wounds in zone III are treated best by angioembolization if there is evidence of significant bleeding.

13. What is the value of other diagnostic studies, such as esophagography, esophagoscopy, laryngoscopy, and bronchoscopy?

Show answer

Routine use of esophagography, bronchoscopy, and laryngoscopy has been advocated in zone I and selected nonoperatively managed zone II patients. Esophagoscopy is combined with esophagography if esophageal injury is suspected; if water-soluble contrast material does not show a leak, barium is used. Missed esophageal injuries can be deadly, with a 20% mortality rate if diagnosis is delayed only 12 hours. Angiography remains the gold standard for diagnosis of arterial injury, and this modality may be therapeutic for zone III injuries (zone III is tough to expose surgically). Intraoperative endoscopy with insufflation may be used provocatively to show an air leak and associated esophageal injury.

14. What is the role of CT?

Show answer
If patients have a high-risk trajectory (i.e., transcervical gunshot wounds), CT may identify the “line of fire” and help determine the need for angiography (see Figure 20-1).

Figure 20-1 Management of penetrating neck trauma.

15. Should an asymptomatic patient with a penetrating neck wound be sent home from the emergency department?

Show answer
No. Life-threatening penetrating neck wounds initially may be difficult to sort out; the safest policy is to observe all patients in the hospital for at least 24 hours.

References
WEB SITES

1. http://www.acssurgery.com/abstracts/acs/acs0504.htm
2. http://www.surgery.ucsf.edu/eastbaytrauma/Protocols/ER%20protocol%20pages/penetrneck.htm

BIBLIOGRAPHY
1. Albuquerque FC, Javedan SP, McDougall CG: Endovascular management of penetrating vertebral artery injuries. J Trauma 53:574-580, 2002. Medline Similar articles Full article
2. Atteberry LR, Dennis JW, Menawat SS, Frykberg ER: Physical examination alone is safe and accurate for evaluation of vascular injuries in penetrating zone II neck trauma. J Am Coll Surg 179:657-662, 1994. Medline Similar articles
3. Biffl WL, Moore EE, Rehse DH, et al: Selective management of penetrating neck trauma based on cervical level of injury. Am J Surg 174:678-682, 1997. Medline Similar articles Full article
4. Demetriades D, Velmahos G, Asensio JA: Cervical pharygoesophageal and laryngotracheal injuries. World J Surg 25:1044-1048, 2001. Medline Similar articles Full article
5. Gracias VH, Reilly PM, Philpott J, et al: Computed tomography in the evaluation of penetrating neck trauma: A preliminary study. Arch Surg 136:1231-1235, 2001. Medline Similar articles Full article
6. Hirshberg A, Wall MJ, Johnston RH, et al: Transcervical gunshot injuries. Am J Surg 167:309, 1993.
7. Mazolewski PJ, Curry JD, Browder T, Fildes J: Computed tomographic scan can be used for surgical decision making in zone II penetrating neck injuries. J Trauma 51:315-319, 2001.
8. McIntyre WB, Blaard JL: Cervicothoracic vascular injuries. Semin Vasc Surg 11:232-242, 1998. Medline Similar articles

1. What are the four principles of medical ethics?

1. Beneficence describes the active role of doing good by intervention.
2. Nonmaleficence is equivalent to saying, “First do no harm.”
3. Autonomy accounts for informed consent, competence, and the patient’s right to refuse treatment and to know what’s going on.
4. Justice means that all patients should receive fair and equal care but that one patient’s care should not squander limited resources for others.

2. What is a do-not-resuscitate (DNR) order?

Show answer
A DNR order instructs the surgeon not to resuscitate the patient if cardiopulmonary arrest occurs; however, a DNR order is much more involved and complicated than the acronym would have you believe. DNR is not absolute.
The Joint Commission for the Accreditation of Healthcare Organizations mandates that hospitals have written guidelines that promote accountability for DNR orders. All DNR orders must be documented in writing, similar to all other orders, in the appropriate section of the patient’s chart. They should specify the treatments to be withheld and treatments that the patient wishes to have implemented. Patients and families must participate in the DNR decision. Moreover, the DNR status should be discussed and reviewed with the other members of the health care team. Finally, a DNR order does not mean that the patient should be medically abandoned.

3. What is the difference between withdrawing and withholding support?

Show answer
A decision to withdraw should not be more problematic than a decision to withhold, because one cannot be sure that an intervention will work until you try it. There is no moral or ethical distinction between withdrawal and withholding of support. Either of the two allows natural progression of disease without the interface of medical technology. The decision to withdraw or withhold support does not equate with patient death, although the probability of death may be greater. After the decision has been made, appropriate management should focus on the patient’s comfort and psychosocial support.

4. What is an advance directive?

Show answer
An advance directive is a method of delineating a competent patient’s wishes for application at a time when he or she is no longer competent. Medical management or the lack thereof can be based on the patient’s wishes rather than a perceived sense of what is best for the patient. Advance directives may be an informal document, such as a living will, or a formal legal document, such as medical durable power of attorney.

5. What is durable power of attorney?

Show answer
A durable power of attorney is a patient-appointed proxy decision maker. The proxy decision maker becomes active as soon as the patient is no longer able to make competent medical decisions. Hence, the durable power of attorney must have been established in advance of the cognitive decline of the patient.

6. What is a living will?

Show answer
A living will, much like a durable power of attorney, is a formal advanced directive in which a competent patient produces a pre-illness guideline for future care in accordance with his or her wishes.

7. What is included in informed consent?

Show answer
Information about the patient’s condition as well as risks and benefits of the recommended treatment are included. Moreover, the operative and nonoperative alternatives (including no treatment) should be discussed with the patient. The patient’s understanding of the information and alternatives should be assessed as part of the informed consent. Finally, informed consent is a voluntary decision made by the patient or on behalf of the patient by a proxy decision maker.

8. What are futile care and medical futility?

Show answer
Ultimately, old age and disease will conquer us all. The definition of medically futile or inappropriate treatment is still debated. Nonetheless, there are four main concepts of medical futility:

1. Health care professionals are not required to provide physiologically futile treatment.
2. Imminent demise argues against treatment if the patient has no likelihood of survival to discharge.
3. Under the concept of lethal condition, medical care is considered futile if the patient will survive temporarily but ultimately expire as a result of the ongoing disease process.
4. Quality of life or qualitative futility argues against treatment if the patient’s quality of life is so poor that it would be unreasonable to prolong life.

Care must be taken, however, in making medical decisions based on futility because these decisions may lead to self-fulfilling prophecies.

9. What are the clinical determinants of brain death?

Show answer
Many of the current concepts of brain death are based on the 1968 report from the ad hoc committee at Harvard Medical School, which called for a new neurologic definition of brain death. But it was not until 1981 that BEMAT justified the neurologic criteria of brain death by stressing the need for intact brainstem integrative function in order for a person to function as a whole. By definition, brain death requires loss of brainstem reflexes in an irreversibly comatose patient. Brain death includes loss of the pupillary, corneal, oculovestibular, oculocephalic, oropharyngeal, and respiratory reflexes for ≥ 6 hours. The patient also should undergo an apnea test, in which the pCO2 is allowed to rise to at least 60 mmHg without coexistent hypoxia. The patient should be observed for the absence of spontaneous breathing. Other ancillary tests are not essential; for example, it is not necessary to perform an intravenous radioisotope cerebral angiogram or a four-vessel contrast cerebral angiogram or to document an isoelectric (”flat”) electroencephalogram.
Of note, all of the above criteria for brain death require the absence of central nervous system depression caused by barbiturates, narcotics, or hypothermia.

10. What is a persistent vegetative state?

Show answer
In a persistent vegetative state, typically seen after improvement of a comatose state, the patient lies motionless and without activity. The patient appears to be awake but does not have awareness of his or her surroundings or higher mental activity. Other names for this entity are coma vigil and akinetic mutism.

11. What is euthanasia?

Show answer
Euthanasia requires that the physician play an active role in assisting in the death of the patient. The concepts of physician-assisted suicide and active and passive euthanasia are highly controversial. In 1992, the Society of Critical Care Medicine published the results of a survey of critical care specialists; 87% had withdrawn life-prolonging support from patients. In addition, the most recent U.S. law pertaining to assisted suicide was passed in Oregon in 1994. This law makes it legal for a physician to prescribe medication to terminally ill patients for the purpose of committing suicide.

12. Who should approach patients’ families about organ donation?

Show answer
Some claim that the physician who has established good rapport with the patient’s family should raise the issue of organ donation. Others believe that the local organ procurement personnel should approach the family because they have greater interest and training in the process. The best approach is probably a combined one.

13. What should patients’ families be told when organ donation is feasible?

Show answer
The surgeon should stress that the patient has died despite an actively beating heart. The family should be questioned about the patient’s wishes regarding organ donation. All topics should be based on the concepts of informed consent. The family should be informed of the likelihood that several patients will benefit from the donated organs. The family needs to understand that there is no guarantee that the organs will be suitable for donation. They should be assured that they are not responsible for the cost of care provided after brain death is determined and that they may refuse organ donation without fear of prejudice.

14. What is the role of the hospital ethics committee?

Show answer
The hospital ethics committee educates hospital staff members, creates policy, and provides a source of consultation.
The function of education is accomplished through grand rounds, seminars, special lectures, and journal clubs. The hospital ethics committee should be viewed as an intrinsic part of the hospital community. Developed policies should be reviewed by other committees and divisions of the hospital to foster a better sense of cohesiveness when ethical and moral dilemmas arise. The consultative function of the ethics committee produces the greatest amount of controversy. In fact, many hospitals negate this function by stating that it interferes with the physician-patient relationship. The hospital ethics committee can and should provide an arena for collaboration and general ethical education within the hospital.

References
BIBLIOGRAPHY
1. Ad Hoc Committee of the Harvard Medical School to Examine the Definition of Brain Death: A definition of irreversible coma. JAMA 205:337-340, 1968.
2. Aminoff MJ: The central nervous system. In Medical Diagnosis and Treatment. Norwalk, CT, Appleton & Lange, 1996.
3. Arnold RM, Siminoff LA, Frader JE: Ethical issues in organ procurement: A review for intensivists. Crit Care Med 12:29-48, 1996. Full article
4. Bernat JL, Culver CM, Gert B: On the definition and criterion of death. Ann Intern Med 94:389-394, 1981. Medline Similar articles Full article
5. Harken AH: Enough is enough. Arch Surg 10:1061-1063, 1999. Full article
6. Kelley DF, Hoyt JW: Ethics consultation. Crit Care Med 12:49-70, 1996.
7. McCollough L, Jones J, Brody B: Surgical Ethics. Oxford, Oxford University Press, 1998.
8. Nyman DJ, Eidelman AL, Sprung CL: Euthanasia. Crit Care Clin 12:85-96, 1996. Medline Similar articles
9. Society of Critical Care Ethics Committee: Attitudes of critical care medicine professionals concerning foregoing life-sustaining treatments. Crit Care Med 20:320-326, 1992.
10. State of Oregon: ORS.251.215, The Oregon Death with Dignity Act. Official 1994 Oregon General Election Handbook, 1994, pp 121-124.
11. Younger SJ: Medical futility. Crit Care Clin 12:165-178, 1996.

1. What is urodynamics?

Show answer
Urodynamic studies assess the functional aspects of the storage and emptying ability of the lower urinary tract (LUT). The principles of urodynamic studies originated from hydrodynamics. The components of urodynamic studies are cystometrogram, leak point pressures, urethral profile pressures, pressure-flow studies, uroflowmetry, and electromyography. These studies have evolved into videourodynamics with the addition of fluoroscopy (i.e., video).

2. What is uroflowmetry?

Show answer
Uroflowmetry is the measurement of voided urine (in milliliters) per unit of time (in seconds). The important elements of the test are voided volume (which should be > 150 mL), maximum flow rate (Qmax), and the curve of the flow (which should be bell shaped). The normal Qmax is > 20 mL/sec in men and > 25 mL/sec in women.

3. What is benign prostatic hyperplasia (BPH)?

Show answer
BPH is benign enlargement of the prostate gland that may lead to bladder outlet obstructive symptoms in men. These symptoms have recently been termed lower urinary tract symptoms (LUTS).

4. What is an American Urological Association (AUA) symptom score?

Show answer
It is a self-reported questionnaire developed and popularized by the AUA for the assessment of bothersome LUTS in men. This questionnaire has seven questions with a maximum score of 35. The higher the score, the more severe and bothersome the symptoms. The AUA symptom score has become an index for both the diagnosis and evaluation of treatment outcome in patients with LUTS.

5. What are the main functions of the LUT?

Show answer
Storage and emptying of urine are the main functions. For practical purposes, all symptoms of LUT dysfunction can be categorized into the malfunction of either storing or emptying ability.

6. What are the control mechanisms for LUT function?

Show answer
The control mechanisms for LUT function are recognized as central and peripheral. The central control mechanisms consist of the cortical portion of the frontal lobe of the brain and pontine micturition center. The peripheral control mechanisms include the thoracic sympathetic and lumbar parasympathetic innervation and neuromuscular apparatus of the LUT organs.

7. What is the role of the autonomic nervous system in the function of the LUT?

Show answer
Sympathetic fibers, which originate from the T10-L2 portion of the spinal cord, innervate the bladder neck and proximal urethra. These fibers mostly control the contraction of the proximal urethra or bladder neck and relaxation of the bladder, which results in storage of urine. The parasympathetic fibers, which originate primarily from the S2-S4 portion of the spinal cord, innervate the bladder body. The parasympathetic innervation allows contraction of the bladder smooth muscle, leading to bladder emptying.

8. What is the role of the somatic nervous system in the function of the LUT?

Show answer
Voluntary control of the striated muscle of the external urinary sphincter is controlled by the somatic nervous system. Somatic fibers are conveyed to the sphincter by the pudendal nerve.

9. What is bulbocavernosal reflex?

Show answer
Bulbocavernosal reflex tests the integrity of peripheral neurologic control of the LUT. This reflex is elicited by stimulation of the glans penis in men or the clitoris in women, which causes contraction of the external anal sphincter or bulbocavernosus muscle. Alternatively, the reflex may be stimulated by pulling the balloon of a Foley catheter against the bladder neck. This reflex is present in all normal men and in approximately 70% of normal women. Absence of this reflex in a man is strongly suggestive of a sacral neurologic lesion.

10. What is the most common cause of incontinence in the geriatric population?

Show answer
The most common are transient causes, mostly external, that disrupt the fragile balance of LUT function in elderly patients and cause urinary incontinence. These causes can be recalled with the mnemonic DIAPPERS:

* Delirium
* Infections
* Atrophic urethritis or vaginitis
* Pharmaceuticals
* Psychological (depression)
* Endocrine (hypercalcemia, hyperglycemia)
* Restricted mobility
* Stool impaction

KEY POINTS: URODYNAMICS AND VOIDING FUNCTION

1. Uroflowmetry is the measurement of voided urine (in milliliters) per unit of time (in seconds).
2. Benign prostatic hypertrophy is benign enlargement of the prostate gland that may lead to bladder outlet obstructive symptoms in men.
3. The sacral roots involved in micturition physiology are S2-S4.

11. What is spinal shock? What type of urinary dysfunction does it cause?

Show answer
Spinal shock is the loss of contractility of the smooth muscle below the level of spinal cord injury, leading to difficulty in bladder emptying or urinary retention. This phenomenon may last from hours to several months with a high chance of reversibility if the spinal cord injury is not permanent.

12. What is autonomic dysreflexia? How is it treated?

Show answer
Autonomic dysreflexia results from systematic outpouring of sympathetic discharge, as in patients with spinal cord lesions at or above the T6 level. This dysreflexia is triggered by distention of the bladder or other stimulus of the bowel or LUT. It is manifested by hypertension, bradycardia, hot flush, sweating, and headache. Initial treatment consists of removal of the stimulus, such as emptying the bladder and placing the patient in a sitting position. Nifedipine or nitroprusside may be used as either prophylaxis or treatment of severe episodes. This condition may lead to significant cerebrovascular complication if untreated.

13. What type of bladder dysfunction is seen in diabetic patients?

Show answer
Diabetic cystopathy is manifested primarily as atonic bladder with difficulty in emptying caused by impaired contractility of the bladder or detrusor muscle.

14. What type of bladder dysfunction is seen in patients with multiple sclerosis (MS)?

Show answer
Urgency (83%), urge incontinence (75%), detrusor hyperreflexia (62%), and detrusor sphincter dyssynergia (25%) are among the most common LUT symptoms in patients with MS. Variation in symptoms depends on the site of involvement by MS. Involvement of pontine pathways (tegmentum) is associated with a much higher rate of urinary symptoms.

15. Which sacral roots control the micturition physiology?

Show answer
S2-S4.
16. What are the causes of urinary retention after abdominal or pelvic surgery? Show answer
They are injuries or disruption of pelvic plexus innervation to the LUT.

17. What is Ogilvie’s syndrome?

Show answer
Acute massive dilatation of the cecum and ascending and transverse colon without organic obstruction is known as Ogilvie’s syndrome. This syndrome can be seen in pelvic urologic surgeries, possibly as a result of an imbalance in parasympathetic stimulation of the colon.

18. What is reflex versus psychic erection?

Show answer
Erection after local stimulation is termed reflex erection. The afferent nerves for reflex erection run in the pudendal nerves, and the efferent fibers are found in the S2-S4 parasympathetic outflow. The psychic erection is caused by stimulation of cerebral erotic centers. The afferent stimuli for psychic erection travel through the thoracolumbar sympathetic outflow and sacral parasympathetic fibers.

References
WEB SITE
http://www.transplantation-soc.org
BIBLIOGRAPHY
1. Bross S, Braun PM, Michel MS, et al: Preoperatively evaluated bladder wall tension as a prognostic parameter for postoperative success after surgery for bladder outlet obstruction. Urol 61:562-566, 2003. Medline Similar articles Full article
2. Holtgrewe HL: Current trends in management of men with lower urinary tract symptoms and benign prostatic hyperplasia. Urology 51(suppl 4A):1-7, 1998.
3. Litwiller SE, Forhman EM, Zimmern PE: Multiple sclerosis and the urologist. J Urol 161:743-757, 1999. Medline Similar articles Full article
4. Mochrer B, Carey M, Wilson D: Laparoscopic colposuspension: A systematic review. Br J Obstet Gynaecol 110:230-235, 2003.
5. Resnick NM, Yalla SV: Geriatric incontinence and voiding dysfunction. In Walsh PC, Retik AB, Vaughan ED, et al (eds): Campbell’s Urology, 7th ed. Philadelphia, W.B. Saunders, 1998.
6. Steers WD, Barrett DM, Wein AJ: Voiding dysfunction, diagnosis, classification and management. In Gillenwater JY, Grayhack JT, Howards SS, Duckett JW (eds): Adult and Pediatric Urology, 3rd ed. St. Louis, Mosby, 1996.
7. Wang CC, Yang SS, Chen YT, Hsieh JH: Videourodynamics identifies the causes of young men with lower urinary tract symptoms and low uroflow. Eur Urol 43:386-390, 2003.

11. Is there any type of stone that cannot be seen on helical CT scan?

Show answer
Patients taking indinavir sulfate (Crixivan) for HIV infection can form stones from the crystals of the medication; these stones are not seen on CT scan.

12. What toxic substance can be produced by using the holmium:YAG laser on uric acid stones?

Show answer
Cyanide is produced from the uric acid. Although this sounds frightening, it is never a problem.

References
WEB SITE
http://www.transplantation-soc.org
BIBLIOGRAPHY
1. Menon M, Resnick M: Urinary lithiasis: Etiology, diagnosis and medical management. In Walsh PC, Retik AB, Vaughan ED, Wein AJ et al (eds): Campbell’s Urology, 8th ed. Philadelphia, W.B. Saunders, 2002, pp 3229-3305.
2. Teichman JM, Vassar GJ, Glickman RD: Holmium: YAG lithotripsy photothermal mechanism converts uric acid calculi to cyanide. J Urol 160:320-324, 1998. Medline Similar articles Full article