Surgical Disorders of the Small Intestine PDF

SURG2 SURGERY 2 Surgical Disorders of the Small Intestine TRANS 3...

SURG2 SURGERY 2 Surgical Disorders of the Small Intestine TRANS 3 MODULE 6 Angelica Versoza-Delgado, MD, DPBS September 13, 2024 LECTURE OUTLINE [BATCH 2023] INFORMATION I Small Intestinal Obstruction A. Etiology Clinical presentation of small intestinal diseases that need 1. Intraabdominal Adhesions Post Surgery surgical evaluation and management are: 2. Neoplasia ○ Bleeding 3. Hernia ○ Peritonitis 4. Inflammatory Stricture ○ Obstruction 5. Congenital or Unknown Small bowel obstruction is a mechanical blockade of normal B. Category intestinal transit through the small intestine, rendering the C. Pathophysiology proximal bowel to dilate, and distal bowel to collapse. 1. Local Consequences 2. Systemic Consequences D. Clinical Features E. Physical Examination F. Laboratory G. Imaging Studies 1. Plain Abdominal X-ray 2. Abdominal CT Scan with Contrast H. Strangulation I. Management 1. Initial Management 2. Urgent Action Figure 2. (L) Proximal bowel dilated; (R) Distal bowel collapsed. 3. Definitive Treatment 4. Treatment Outcomes 5. Rate of Recurrence II Summary LECTURE OBJECTIVES 1. Correctly diagnose small intestinal obstruction 2. Institute appropriate initial management 3. Refer to the appropriate specialty for definitive management 🧠 Must Know 📖 Book 📝 Previous Trans Figure 3. (Arrow) At the transition zone or Point of obstruction: caused primarily by intra-abdominal adhesions related to previous abdominal surgery. I. SMALL INTESTINAL OBSTRUCTION Gastrointestinal obstruction is defined as the mechanical disruption Doctor’s Notes of the passage of intestinal contents along the bowel. Roughly around 8 to 9 liters of fluid enter the small intestines Bowels proximal to the obstruction are usually dilated. daily Those distal or beyond the point of obstruction are collapsed. ○ In the physiologic state, the small bowels absorb around 80% The causes are divided according to its relationship to the bowel of these fluids wall: ○ It leaves around 1.5 liters of fluid to enter your colon for final fluid absorption 1 Intraluminal Point of obstruction is within the bowel lumen (ex. foreign bodies, gallstones, or meconium) A. ETIOLOGY 2 Intramural Problem with the bowel wall itself (ex. thickening, inflammatory, tumors, strictures) 1. INTRA ABDOMINAL ADHESIONS POST SURGERY (60%) 3 Extrinsic Point of obstruction is outside the bowel wall (ex. The most common cause of bowel obstruction adhesions, hernias, or carcinomatosis) All patients who have undergone a previous abdominal operation (open > laparoscopic) for any indication will have adhesions as part of the normal wound healing process. The balance between fibrin deposition and degradation is critical in determining normal peritoneal healing or adhesion formation. ○ Sometimes, if there is more deposition of fibrin as the wound heals, then you have adhesion formation Risk factors for adhesive small bowel obstruction: ○ Type of surgery ○ Technique of the surgeon ○ Extent or degree of perineal inflammation or damage at the time of obstruction Table 1. Specifics of the Risk Factors Classified as Low or High Risk LOW RISK FACTORS HIGH RISK FACTORS Laparoscopic procedure Open surgery Figure 1. Diagram of the classification of causes for gastrointestinal obstruction. Source: Dr. Versoza-Delgado’s Video Lecture on Small Bowel Obstruction Group 4B | Surgical Disorders of the Small Intestine 1 of 11  Other site in the abdomen Pelvic or lower abdominal surgery ○ When you are talking to the patient and categorized them as procedure (e.g. gynecologic, having partial, simple or open obstruction, these have better colorectal surgeries and prognosis appendectomy) ○ However, if patients are categorized as complete, strangulated or closed loop obstruction, these needs Elective Procedure Emergency procedure (less immediate surgical resection meticulous handling of tissue; there is some degree of inflammation or infection in the abdomen) C. PATHOPHYSIOLOGY NOTE: This part is integrated already with Batch 2025’s information. No omental resection Omental resection (barrier between the peritoneum and 1 Mucosal injury intestinal organ is lost) 2 Distention from endoluminal gas and fluid accumulation Other trauma procedure Penetrating abdominal trauma (e.g. (digestive secretions and ingested air and fluid) gunshot wounds which are commonly associated with 3 Intestinal hypersecretion peritonitis due to bowel 4 Inhibition of fluid and electrolyte resorption perforations) 5 Edema and congestion of the bowel wall No peritonitis With peritonitis 6 Altered wall permeability No operation Multiple operations (multiple laparotomies in the past 5 years, 7 Bacterial stasis and translocation the higher the incidence of 8 Septic complications post-operative adhesion) Source: Dr. Versoza-Delgado’s Video Lecture on Small Bowel Obstruction Local and systemic consequences are determined by: ○ Duration and degree of obstruction ○ Presence and severity of ischemia The longer duration and severe degree of intestinal obstruction [BATCH 2025] INFORMATION accompanied by ischemia cause more local and systemic damage 2. NEOPLASIA (20%) to the patient. With colorectal and ovarian metastases being the most common. It may be caused by the primary tumor, its peritoneal metastases, 1. LOCAL CONSEQUENCES or bulky lymph node metastases of the primary tumor. Health of the bowel mucosa is vital. The first site of injury is the Primary small intestinal tumors are not common mucosa. Epithelial damage occurs within the first 4–6 hours of simple 3. HERNIA (10%) Obstruction that progresses → focal necrosis within 8–12 hours ○ This is due to the progressive distention of the proximal bowel May be inguinal, femoral, ventral, or umbilical from accumulated air and gas. It is the most common cause in underdeveloped countries and Strangulation exacerbates the damage, causing extensive patients with no previous abdominal surgery mucosal necrosis and sloughing. (From 2023) Obstruction causes accumulation of fluid, swallowed air, and gas 4. INFLAMMATORY STRICTURE (5%) within the proximal bowel lumen, causing bowel distention. Crohn's disease, small-bowel volvulus, intussusception, radiation ○ The more accumulated food, fluid, or gas inside the small enteritis, endometriosis, infection, foreign body, anastomotic bowel, the more distended it can become. stricture such as gallstone, fecalith and sclerosis The most frequent cause of intestinal obstruction in infants aged 6 to 36 months is intussusception Examples of infections are pelvic inflammatory disease, tuberculosis, parasitic infections 5. CONGENITAL OR UNKNOWN (5%) B. CATEGORY Obstructions can be categorized based on the degree of: 1 Partial or Obstruction to flow Complete Figure 4. Small Intestinal Obstruction (Red circle); Bowel mucosa as the first site 2 Simple or Absence or presence of ischemia of injury (Yellow Arrow). Lecture video 2025 Strangulated 3 Closed or Occlusion of both proximal and distal parts or 2. SYSTEMIC CONSEQUENCES Open loop only the distal portion of involved bowel Fluid accumulates due to impaired water and electrolyte segment absorption and enhanced mucosal secretion. ○ This results in a net fluid shift of the isotonic fluid from These categories influence prognostication and treatment intravascular space into the bowel wall. planning. [BATCH 2025] FACE-TO-FACE LECTURE NOTES Bowel strangulation - significant degree of ischemia Simple - no ischemia Open loop - one point of obstruction Closed loop - two points of obstruction ○ The segment between the two points is a closed loop obstruction These categories influence prognostication and treatment planning Group 4B | Surgical Disorders of the Small Intestine 2 of 11  [BATCH 2025] FACE-TO-FACE LECTURE NOTES There are two ends of the disease, one causes hypovolemia, hypovolemic shock, or hypotension, the other causes sepsis. Hypovolemia/hypotension - as food and gas accumulates, the patient would vomit ○ This is the natural response of the small bowel, it tends to backflow when there is obstruction inside. ○ Vomiting leads to the patient losing water, electrolytes, and develops hypotension Recall histology: Along the walls of small bowel, microvessels are found, delivering blood to small bowel wall ○ If there is distension of small bowel wall, there tends to be a compression of these microvessels along the submucosal Figure 5. Small Intestinal Obstruction (Red circle); Fluid/air accumulation into layer, leading to venous congestion the bowel lumen (Yellow Arrow). Lecture video 2025. ○ Venous congestion causes shift of fluid to extravascular space of the bowel wall causing edema in the bowel wall The stasis of intestinal contents causes bacterial overgrowth within ○ Imagine 4 to 6 meters of small bowel, and you fill it up with the lumen. water, that requires a lot of fluid. ○ Disruption of normal bowel microflora leads to bacterial ○ This contributes to the hypovolemia of the patient; instead of translocation from intraluminal to mesenteric lymph nodes and the fluid being in the intravascular space, it deposits to the systemic organs. third space and then transfers to the bowel wall, causing a Studies have shown that translocation of bacteria into submucosa loss of water, electrolytes, and eventually hypovolemic shock. happens within 36 minutes of simple obstruction. It is compounding. ○ Some studies suggest that the bacterial translocation into On the other hand of the spectrum, you have septic complications submucosa and beyond bowel wall will lead to septic from small bowel obstruction complication of obstruction. ○ Venous compression → decreased oxygenation of mucosa → decreased unity of small bowel wall → leaky bowel wall → bacteria from intraluminal contents translocates into small vessels → sepsis Generally, patients present with hypovolemia, and also sepsis if you don’t treat early enough. D. CLINICAL FEATURES Most patients with intestinal obstruction typically present with the following features: PROXIMAL OBSTRUCTIONS: Paroxysms of pain typically occur at 5-minute intervals Figure 6. Small Intestinal Obstruction (Red circle); Bacterial stasis (Yellow Acute onset of DISTAL OBSTRUCTIONS: Less Arrow). Lecture video 2025. 1 cramping and frequent abdominal cramping abdominal pain The longer the duration of the The stasis of intestinal contents causes bacterial overgrowth within obstruction, decreased bowel motility and the lumen. decreased abdominal pain will eventually Therefore, systemic manifestation relates to hypovolemia and occur inflammatory response with or without bowel ischemia and gangrene. PROXIMAL OBSTRUCTIONS: Profuse Hypovolemia mainly results from the shift of the fluid from the vomiting intravascular space into the intestinal lumen, bowel wall, and DISTAL OBSTRUCTIONS: Have lesser peritoneal cavity. (Third Spacing) 2 Vomiting vomiting ○ Anorexia and vomiting further reduce intravascular volume. May be feculent or fecaloid due to ○ Bowel ischemia exacerbates fluid loss locally and systemically bacterial stasis in longstanding through generalized microvascular leak. obstruction Activation of inflammatory mediators contributes to remote organ PROXIMAL OBSTRUCTIONS: Have failure and mortality caused by bowel ischemia and reperfusion Abdominal less abdominal distention injury. 3 distention DISTAL OBSTRUCTIONS: Experience ○ Inflammatory mediators include neutrophils, complement, more abdominal distention cytokines, eicosanoids, and oxygen-derived free radicals. Non Passage of both flatus/air and stool/bowel movement within 24 hours VITAL SYMPTOM OF OBSTRUCTION Usually suggests a complete degree of obstruction Pitfall in relying on this symptom: 4 Obstipation patients with partial may not have obstipation and continue to pass out flatus and stool, while patients with complete obstruction can continue to pass stool that was distal to the point of obstruction Continuous localized and severe pain strongly suggests small bowel Sudden and strangulation 5 severe pain Closed loop obstruction, in particular, can present as sudden and severe Figure 7. Mechanism of Hypovolemia and Sepsis. Lecture video. unremitting abdominal pain Group 4B | Surgical Disorders of the Small Intestine 3 of 11 E. PHYSICAL EXAMINATION 1 Patients with simple, small bowel General obstruction are likely to be acutely ill, Inspection showing signs of hypovolemia and abdominal distention 2 Period of increased bowel sounds ○ High-pitched or musical sounds separated by periods of quiet bowel sounds/loss of bowel sounds Bowel sounds may eventually disappear when bowel motility decreases in prolonged obstruction Auscultation ○ When the bowel has been markedly distended for several days, it has been stretched out for a long time, Figure 8. Plain Abdominal X-ray (Left) Supine: Loops of small bowel (upper so peristalsis no longer occurs, arrow) with a collapsed colon (lower arrow). (Right) Upright: Multiple air fluid thus, bowel sounds are absent levels described as a Step Ladder Pattern (arrows). Borborygmi are pronounced rumbling bowel sounds corresponding with colic. 2. ABDOMINAL CT SCAN WITH CONTRAST Distended and minimally tender AXIAL abdomen. ○ Triple contrast abdominal CT scan demonstrates Tenderness or other peritoneal signs non-progression of contrast material in a segment of the bowel (such as abdominal guarding) suggests CORONAL strangulation of the bowel wall and this ○ Feces sign is a radiologic finding (specific finding) in small warrants urgent surgical management. bowel obstruction. ○ indicate urgent laparotomy Notes from 2025 Trans 3 Abdomen The presence of tender mass at an inguinal, femoral, or umbilical hernia site strongly suggests this as the cause of obstruction. Abdominal distention may be minimal in proximal small bowel obstruction presenting with vomiting. Closed-loop small bowel obstruction can present with pain out of proportion. F. LABORATORY Figure 9. Abdominal CT scan with contrast. Axial view(Left) Coronal view (Right). Leukocytosis and hemoconcentration Yellow arrow points to the area of obstruction from hypovolemia and fluid losses which 1 CBC are ongoing process in obstruction H. STRANGULATION Significant neutrophilia and immature Clinical features of small bowel strangulation warrant urgent WBC forms suggest strangulation surgical management (usually laparotomy) Renal Function High serum BUN and Creatinine levels Delays in management can lead to bowel gangrene which is 2 managed with bowel resection of all non-viable intestines. Tests Signs and Symptoms: Abnormal serum Electrolytes ○ Continuous abdominal pain 3 Electrolytes concentration (Na, K, Cl) ○ Fever Metabolic acidosis suggests severe ○ Tachycardia 4 ABG hypovolemia with or without intestinal ○ Abdominal guarding (signs of sepsis) ischemia Laboratory Exam: ○ Marked leukocytosis ○ C-Reactive Protein elevation G. IMAGING STUDIES ○ Serum Lactate elevation Frequently used in the diagnosis of small intestinal obstruction are ○ Plain Abdominal X-ray I. MANAGEMENT ○ Contrast CT Scan 1. INITIAL MANAGEMENT 1. PLAIN ABDOMINAL X-RAY SUPINE MEDICAL ○ Multiple fluid- and gas-filled small bowel loops may be appreciated ○ Loops of small bowel with a collapsed colon IV FLUID RESUSCITATION UPRIGHT Restoration of intravascular volume by infusion of isotonic fluid is ○ Demonstrates multiple air fluid levels described as a Step paramount. Ladder Pattern. Urine output monitoring as well as normalization of vital signs These findings usually represent complete bowel indicate adequacy of fluid resuscitation. obstruction but plain abdominal film has its limitations Electrolyte imbalances and metabolic acidosis should be corrected (20-30% of cases with proven small bowel obstruction as soon as possible, also by giving fluid resuscitation have equivocal or normal studies) NASOGASTRIC TUBE (NGT) NGT can help decompress the distended small bowel and minimizes the risk of aspiration Group 4B | Surgical Disorders of the Small Intestine 4 of 11  The more distended the bowel is, the higher the degree of ischemia ANTIBIOTICS Typically not warranted in the management of simple and not operative small bowel obstruction However, broad spectrum antibiotics with coverage for coverage for gram negative aerobes and anaerobes should be given to all patients set to undergo surgical treatment or laparotomy, in those presenting with complete gut obstruction, or a strangulated small bowel obstruction. 2. URGENT ACTION Immediate surgical intervention is necessary for patients with small bowel strangulation or peritonitis Closed-loop or complete small bowel obstruction ○ These can lead to to bowel ischemia and perforation in 30% of cases and can lead to mortality when surgical management is delayed Simple obstruction IF: ○ CT findings: no contrast in colon within 8 hours, mesenteric Figure 12. (1A) Dilated small bowels, (1B) Adhesion band, (1C) Large bowel edema/ stranding, small bowel feces sign adhesions, (1D) Undyed barbed suture 3. DEFINITIVE TREATMENT 4. TREATMENT OUTCOMES Goal of surgery is to address the transition point or the site of Immediate risk: obstruction. Mortality risks Laparotomy is a major surgical procedure that involves a midline ○ Can range 2–8% abdominal incision. ○ Most commonly associated risk factors: ○ This allows access to the contents of the abdomen: 1 Advanced age Identify the site of obstruction Perform adhesiolysis or enterolysis (releasing of adhesion 2 American Society of Anesthesiologists (ASA) class 3 or higher to relieve obstruction) Small bowel resection may be necessary in some cases 3 Associated chronic illness when there is presence of bowel gangrene and or 4 Strangulated obstruction perforations 5 Treatment delay Morbidity Risks ○ Morbidity after surgery ranges from 12–47%. ○ Bowel resection is associated with higher morbidity than simple lysis of adhesions. ○ Pulmonary embolism because usually these patients do not ambulate. Table 2. Morbidity Risks MEDICAL COMPLICATIONS SURGICAL COMPLICATIONS Pneumonia, respiratory failure Wound and intra-abdominal infections Pulmonary embolism Intra-abdominal bleeding Cardiac complications Bowel necrosis and perforation Prolonged ileum Figure 10. Gangrenous bowel (black, ischemic, and dead) Source: Dr. Versoza-Delgado’s Video Lecture on Small Bowel Obstruction 5. RATE OF RECURRENCE High recurrence rate Most recurrences occur within 5 years ○ 18% at 10 years and 29% at 30 years of follow up Evidence does suggest that operative treatment of adhesive small obstruction has lower recurrence and longer interval of repeated admission as compared to patients who undergo non-operative or conservative management. II. SUMMARY The majority of small bowel obstructions are related to previous abdominal surgery. Most common presenting symptoms are pain, vomiting, abdominal distention, and obstipation. Plain abdominal x rays and abdominal CT scans can help confirm the diagnosis. Figure 11. Intussusception (telescoping of the small bowel within itself) Lead point - causing the telescoping by dragging the other parts of the small Initial management is medical by doing fluid resuscitation and bowel within the lumen → complete obstruction inserting NGT for decompression. Group 4B | Surgical Disorders of the Small Intestine 5 of 11  Referral to a surgical specialist is needed in patients with PATHOPHYSIOLOGY OF SMALL BOWEL ISCHEMIA complete closed loop or strangulated small bowel obstruction or Health of the bowel mucosa is vital. When the mucosa is non -resolving simple bowel obstruction for definitive management. compromised, there will be subsequent effects on the submucosa, ○ Surgery is the definitive management muscularis and serosa. Usually the distention from the endothelial gasses and the fluid III. SYNCHRONOUS SESSION accumulation will induce even more the secretions of the small bowel mucosa A. SMALL INTESTINE OBSTRUCTION ○ If that happens, there is inhibition of fluid and electrolyte reabsorption. It will predispose the mucosa to more edema and congestion. ANATOMY AND PHYSIOLOGY ○ Eventually, when there is much fluid due to the edema in the The GIT starts with the stomach, then the small intestine, large bowel wall, there will be compromised blood supply on the intestine, down to the rectal canal capillaries that are within the bowel wall → hence, Its main purpose is involved in digestion and absorption of the predisposing a patient to some degree of ischemia nutrients from food; The outer permeability of the small bowel also predisposes the Takes part in the immunity and endocrine systems, it is the largest patient to bacterial stasis and translocation leading to eventual reservoir of immune and hormone-producing cells. sepsis The total length is around 4-6 m, from the duodenum to the ○ Complications will then arise terminal ileum. The systemic manifestation relate to hypovolemia and The small intestine is mainly composed of the duodenum, jejunum, inflammatory response with or without bowel ischemia and and ileum;, gangrene. Histology of the small intestine (composed of 4 layers): ○ Hypovolemia mainly results from the shift of fluid from the ○ Mucosa - Innermost intravascular space and into the bowel wall and peritoneal ○ Submucosa - Contains small vessels, mainly composed of cavity. connective tissue Anorexia and vomiting further reduce intravascular volume. ○ Muscularis propria - Where the muscles involved in contraction Bowel ischemia exacerbates fluid loss locally and are, responsible for propelling contents from proximal to distal systemically through generalized microvascular leak. ○ Serosa - Outermost, like the skin Complications in terms of 2 aspects: hypovolemia and sepsis The histology and pathology of the diseases of the small intestine are closely related CLINICAL FEATURES ○ Injuries start mainly at the mucosa, spreading outward towards the abdominal wall One caveat here is patients with obstructions may not have Around 8-9 L of fluid enters the small intestines daily, broken down obstipation. Not all of them will be obstipated, some of them will in Figure 1 still be able to pass out gas. Anything with mucosa secretes fluid, which goes through the entire ○ It depends on the degree of obstruction. GIT PHYSICAL FINDINGS AUSCULTATION Bowel sounds may eventually disappear when bowel motility decreases in prolonged obstruction ○ In patients with several days of bowel obstruction, when you auscultate the abdomen, you won’t be able to appreciate any bowel sounds because the bowel wall has been distended markedly. ○ Imagine a rubber band. It is not elastic as it was before. When you stretch it out, it won’t undergo peristalsis, therefore, you won’t hear any bowel sounds. PALPATION May be tender or nontender Not all obstruction will present with abdominal pain Guarding will suggest strangulation ○ Anytime you appreciate guarding, rigidity, rebound tenderness → acute abdomen patients ○ They warrant urgent surgical management LABORATORY Abnormal serum Electrolytes concentration ○ There is inability of the small bowel to absorb all these fluids and electrolytes because of the obstruction IMAGING PLAIN ABDOMINAL X-RAY Distended small bowels On a normal patient, you will not see much gas on 1 Supine the center of the film Figure 13. Typical quantities of fluid that enters and leaves the small intestine Shows the marked lining of the small bowel daily. 2 Upright Determining air fluid levels Around 80% of the fluid is reabsorbed along the small bowel length, which leaves approximately 1.5 L of fluid enters the colon, where the rest of absorption happens ABDOMINAL CT SCAN WITH CONTRAST With the production of this amount of fluid, problems that arise in the small bowel, will result in large fluid retention 1 Axial Group 4B | Surgical Disorders of the Small Intestine 6 of 11  Feces sign ○ Small bowel is not supposed to have feces, this must be mainly fluid. 2 Coronal ○ Feces form in the colon When you see this, then bacterial translocation already and feces is already forming the small bowel already. B. CROHN’S DISEASE A chronic idiopathic transmural Inflammation disease with skip lesions that affects any part of the gastrointestinal tract 80% involves the small bowel 1. PATHOPHYSIOLOGY Majority of the lesions, you will see in the terminal ileum. There is sustained transmural inflammation due to abnormal epithelial barrier function. The earliest lesion is aphthous ulcer Later presentation is the cobblestone appearance of the small bowel mucosa and gross findings during surgery includes fat wrapping - encroachment of the mesenteric fat into the serosa which is pathognomonic. ○ Aphthous ulcer - surrounding mucosa has villi, a little bit airy, white based ulcer devoid of villi, diagnosed endoscopically ○ Fat wrapping - creeping into the serosa Figure 14. (L) Aphthous ulcer, (R) Fat wrapping. Most common symptoms: Figure 15. Extraintestinal manifestations of Crohn’s disease. ○ Chronic abdominal pain ○ Diarrhea Complications: ○ Weight loss ○ Stricture formation (most common) ○ Others: Fever, Growth retardation in children As this is an inflammatory disease, inflammation resolves, Extraintestinal manifestations of Crohn’s disease: leading to scarring, then it becomes a continuous cycle as ○ It may be dermatologic, rheumatologic, ocular, hepatobiliary, a chronic disease of healing and scarring. Eventually, urologic, and other miscellaneous manifestations. there will be multiple strictures along the bowel wall ○ Intra-abdominal abscesses ○ Enteric fistulas ○ Free perforations 2. DIAGNOSIS Diagnosis is mainly through history and physical examination, endoscopy with biopsy, CBC, electrolytes, renal and liver functions, abdominal CT scan (only to assess complication). 3. MANAGEMENT There is no cure for Crohn’s disease Medical therapy is the cornerstone of treatment ○ Give medications to manage inflammation Surgery is reserved for failure of medical therapy or if with concomitant complications Surgery has very little role, usually just reserved for failure of medical therapy, or if patients has complications already. Group 4B | Surgical Disorders of the Small Intestine 7 of 11  ○ Ideally, maximize medical therapy first, try all the medications able to control the inflammation first. ○ Signs of sepsis and strangulation then surgery is required. C. SMALL BOWEL NEOPLASMS 1. INCIDENCE Rare tumors in the small bowel ( Malignant Benign conditions: ○ Leiomyoma ○ Submucosal tumors ○ Lipomas ○ These are not life threatening but if they do grow to a certain size then they can cause obstruction Figure 16. Indications for surgical intervention in Crohn’s disease Surgical Intervention in Crohn’s disease Figure 17. Features of small-intestinal malignancies ○ When the patient has: Acute onset of severe disease Most common malignancy is Adenocarcinoma Toxic megacolon ○ Small bowel adenocarcinoma Failure of medical therapy (persistence of symptoms ○ 35%- 50% despite long term steroid use or recurrent symptoms) ○ In the small bowel, usually happens in the duodenum Development of complications ○ Very rare in the jejunum and ileum ○ The most common are usually: Other malignancies: Obstruction ○ Carcinoid tumors Perforation ○ Lymphoma Complicated fistulas ○ Gastrointestinal stromal tumors (GIST) Hemorrhage (bleeding) Commonly arise in your stomach Risk of malignancy If outside the stomach, most common site is the jejunum 4. SURGICAL THERAPY 2. CLINICAL PRESENTATION Type of surgery depends on the type of complication present When these tumors start growing in its initial stages, patients are Resection and anastomosis usually asymptomatic ○ Commonly performed if you have a simple stricture causing ○ As long as all the liquid and all the gas are able to pass some degree of obstruction through, they usually don't present with any symptoms. ○ Dont just take out the area with obstruction, you should take When a tumor starts to grow to a significant size then they can out 2 cm margin of gross normal tissue develop some degree of partial gut obstruction. Because the stricture seen by our own eyes extends well ○ Partial gut obstruction causes nausea, vomiting, colicky beyond through the layers of the small bowel and you dont abdominal pain (feeling of twisting of abdomen) want to leave behind any active inflammatory tissue that’s ○ Can also present with bleeding, sometimes lipoma likes to why it is important to excise a margin around the tissue present with bleeding so if FOBT is done there is positive result Strictureplasty ○ Can also present with hematochezia ○ To address intestinal strictures without decreasing the amount When the tumor start to grow to a significant size, you will be able of small bowel length to palpate it especially when the patient has very thin ○ Open up the strictures without resecting the small bowel subcutaneous tissue ○ Rarely do this because of the high complications ○ Quite difficult to do in a larger patient Intestinal bypasses If the disease is cancer, you can have cancer related symptoms ○ In the setting of complex enteric fistulas and/or abscesses usually: ○ Putting together two segments of the bowel that appear normal ○ Cachexia (due to progressive disease) ○ Connect the two strictures with normal bowel then connect ○ Ascites them and the intestinal contents will bypass the stricture ○ Peritoneal disease ○ This is done in the setting of complex fistulas or if the patient ○ Jaundice has abscesses because it is dangerous to manipulate these. Adenocarcinoma is most commonly located in the ○ Patient can bleed, might not get good margins, bowel is tucked duodenum. If you develop adenocarcinoma along the 2nd down into the retroperitoneum portion of the duodenum then they can present with obstructive jaundice. 5. OUTCOMES No treatment → Lifelong disease Complications are common (15-30%) ○ Wound infections ○ Can develop into intra-abdominal abscesses ○ Anastomotic leaks What surgeons are most scared of because stitching together inflamed bowels, they don't hold the suture due to it being friable. Very common ○ Obstruction Recurrence of active disease occur within 1 year (70% of patients) and up to 85% in 3 years ○ Usually come back and complain of abdominal pain, diarrhea, fever, and painful abdomen again Group 4B | Surgical Disorders of the Small Intestine 8 of 11  Figure 18. Jejunal GIST. This patient presented with overt obscure GI bleeding BALLOON ENTEROSCOPY and was found to have a 7-cm jejunal GIST. Laparoscopic view of the mass (black arrow), arising from the antimesenteric side of the small bowel (*). He Not available in our country underwent a successful laparoscopic resection. Uncomfortable for the patient Done under general anesthesia If the GIST is extragastric, it is usually located in the jejunum Long colonoscopy You can see how it can cause symptoms → Growing from the ○ Can visualize rectum, colon, terminal ileum and sometimes the bowel wall → causes obstruction → patient complaints of jejunum abdominal pain CHEST RADIOGRAPHY 3. DIAGNOSTICS Examples are gastrografin studies and barium studies Ask the patient to swallow something radiopaque, then take TUMOR MARKERS several x-rays of them to see if there’s an abnormality in the transit of the contrast material they ingested Can ask for tumor markers ○ Metastatic adenocarcinoma usually has elevated CAA but not 4. TREATMENT all so you don't use it to diagnose. ○ Carcinoid tumors present with elevated chromogranin A DEBRIDEMENT AND SURGICAL RESECTION ABDOMINAL CT SCAN WITH TRIPLE CONTRAST The treatment is surgical resection, whether it’s benign or You can do abdominal CT scan with triple contrast malignant If your tumor is significant in size ○ Can be approached laparoscopically or surgically ○ Even if the patient is asymptomatic you can see it Resect the boweland perform anastomosis ○ If the bowels are not healthy, don’t perform anastomosis and PET SCANS bring them out of the abdomen. To establish the clinical stage, know what you’re dealing with, and WHIPPLE PROCEDURE how advanced the disease is If dealing with a malignancy they would be hypermetabolic and Performed for duodenal tumors since there is no way to resect hyperactive on PET scans duodenum and leave the pancreas hanging since it needs to be attached ENDOSCOPY EGD - for duodenum tumors ○ Can only detect upper GI tumors until the duodenum usually in until the 2nd portion If the tumor is there you can see it and do biopsy using EGD COLONOSCOPY For terminal ileum tumors When you visualize the large intestine on colonoscopy, you can traverse the ileocecal valve and see the terminal ileum (the last few centimeters of the small bowel) If the pathology is located in these locations, you can visualize and do biopsy using colonoscopy CAPSULE ENDOSCOPY Figure 20. Whipple Procedure Patient will swallow a capsule with a camera at the end. Images can be tracked through the capsule until the patient ENDOSCOPIC RECEPTIONS passes it through the feces. For smaller tumors less than 1 cm, may it be in the terminal ileum or the duodenum, can be taken endoscopically (endoscopic mucosal resection or endoscopic submucosal dissection) COLONOSCOPY Able to resect tumors >2 cm ○ No need to resect the whole bowel Resect only the mucosa of the tumor then clip the defect C. SHORT BOWEL SYNDROME There’s significant malabsorption occurring then more than 50-80% of the small bowel is resected. This causes malabsorption. The severity will depend on the following factors: ○ Residual small bowel length Severity of malabsorption is dependent on the residual small bowel. Total length of the small bowel is 4-6 meters. If there is 0.6-1 meter left, then there is Short Bowel Syndrome. ○ Absence/ presence of a functioning colon Absence or presence of a functioning colon adds to the degree of malabsorption. Whatever the small bowels cannot absorb, the colon will accept and it will absorb that by itself. Figure 19. Capsule Endoscopy ○ Intact ileocecal valve Ileocecal valve controls flow of fluid into the large bowel. Intact ileocecal valve leads to higher absorption. Group 4B | Surgical Disorders of the Small Intestine 9 of 11  Connection between the terminal ileum and the colon. It IV. REVIEW QUESTIONS regulates the amount of fluid that exits the small bowel and enters the colon. Intact valve will allow more contact of the No. QUESTIONS fluid in the small bowel and will facilitate more absorption. 1 What category of obstruction best describes a condition Non-intact ileocecal valve will cause the contact time to wherein there is an occlusion of both the proximal and shorten, resulting in malabsorption. distal part of the bowel? ○ Ileal resection and Crohn’s disease A. Strangulated Have a higher degree of malabsorption. B. Complete Ileal resection: ileum is involved in the absorption of bile C. Closed loop acids and vitamin B12. Resection of the ileum will cause D. Simple further malabsorption ○ Remaining small bowel 2 A 37 y/o woman was seen at the E.R. with a one-week this matters when the remaining bowel is diseased, history of mild colicky abdominal pain, anorexia with especially when taking out less than 50% of the diseased occasional vomiting, and not passing flatus and bowel bowel (strictured or has fistula), then this bowel can still not movement for 48 hours. On P.E. she has dry lips and oral participate in absorption, resulting again in some degree of mucosa, the abdomen is distended with hyperactive bowel malabsorption sounds and minimal tenderness. An appendectomy scar is The higher the degree of malabsorption, the higher the seen at the RLQ. BP is 120/80, PR: 100/min. RR: 24/min dependence of patients to total parenteral nutrition. Temp. Afebrile. CBC WBC of 11,000. What is the most probable working impression? MANAGEMENT A. Closed-loop intestinal obstruction Establish a route of nutrition: B. Strangulated intestinal Obstruction ○ Enteral C. Complete Intestinal Obstruction Using the gut, either the patient eats by mouth or a tube is D. Simple Intestinal Obstruction placed into the stomach, small bowel (usually the jejunum; 3 What do you expect to hear upon auscultation in a patient jejunostomy) with decreased bowel motility due to prolonged ○ Parenteral nutrition obstruction? Giving the nutrition through IV A. No bowel sounds Medications may be given, but there is low effectivity B. Increased bowel sounds ○ Antimotility agents C. Decreased bowel sounds Slow down the movement of fluid so the small bowel has D. High-pitched, musical sounds enough time to absorb nutrients ○ Proton Pump Inhibitors 4 Question. Paroxysms of pain occuring at 5-minute intervals ○ H2 receptor antagonists are typical of what type of obstruction? Decrease gastric secretions A. Proximal obstruction Surgery B. Distal obstruction ○ Insulation of intestinal motility especially when the patient in an C. Neither A nor B ostomy 5 Based on current evidence, what is the recommended ○ Ex. The surgeon performed a bowel surgery then the patient treatment for strangulated small intestinal obstruction has a stoma, such as when the ileum is in the abdominal wall, caused by postoperative adhesion? or there is an ileostomy or colostomy, this decreases the A. IV Fluids, Nasogastric tube, Antibiotics amount of the small or large bowel that is functioning B. IV Fluids, Nasogastric tube ○ The main goal is to restore the intestinal continuity, because C. IV Fluids, Nasogastric tube, Antibiotics, Exploratory we would like to use the entire bowel length (small or large Laparotomy bowel), the stoma is removed D. IV Fluids Serial transverse enteroplasty (STEP) procedure ○ Elongate the absorption surface of the small bowel 6 What is the most common primary malignancy of the small ○ Making small incisions along the surface intestine? ○ Not usually done A. Carcinoid tumor of the jejunum B. Gastrointestinal stromal tumor (GIST) of the duodenum C. Lymphoma of the ileum D. Adenocarcinoma of the duodenum 7 TRUE OR FALSE. The more distended the bowel is, the higher the degree of ischemia A. True B. False 8 TRUE OR FALSE. Electrolyte imbalances and metabolic acidosis should be corrected as soon as possible, also by giving antibiotics A. True B. False 9 70 y/o healthy man with well-controlled diabetes and hypertension underwent an uneventful exploratory laparotomy adhesiolysis for intestinal obstruction due to a previous surgery. Which among the following clinical parameters is a risk factor for mortality for this patient? Figure 21. STEP Procedure A. Advanced Age Intestinal transplant B. Chronic Illness ○ Rarely used, only a few have been done globally. C. Operation for obstruction Rarely studied, because it is rarely performed. D. ASA Classification ○ Very high complication rate due to rejection of the body. ○ Last resort for patients with no other options. IV. APA REFERENCES Versoza-Delgado, A. (2024). Surgical Disorders of the Small Intestine. [Video Lecture]. Accessed via Moodle. Group 4B | Surgical Disorders of the Small Intestine 10 of 11  10 A 58 y/o man was seen at the E.R. with a 2-day history of 5 CORRECT ANSWER: C. IV Fluids, Nasogastric tube, continuous abdominal pain with increasing intensity, Antibiotics, Exploratory Laparotomy anorexia, and vomiting. He has no flatus and no bowel movement for more than 2 days. On P.E., he has dry lips INITIAL MANAGEMENT and oral mucosa, the abdomen is markedly distended with Medical hypoactive bowel sounds and tenderness all over. A → IV Fluids midline incisional scar is seen from a previous operation. Restoration of intravascular volume by infusion of BP is 100/60, PR: 110/min. RR: 30/min Temp. 38.5. IV fluid isotonic fluid is paramount. was started. NGT was inserted with feculent output. What Urine output monitoring as well as normalization of is the recommended next step in management? vital signs indicate adequacy of fluid resuscitation. A. Request for CT scan with Triple Contrast Electrolyte imbalances and metabolic acidosis should B. Refer to Internal Medicine for medical management be corrected as soon as possible C. Refer to Surgery for Immediate surgical intervention →Nasogastric Tube (NGT) D. Observe for progression of symptom It may help decompress the distended small bowel and it minimizes the risk of aspiration. 11 What category of obstruction best describes a condition Remember that the more distended the bowel is, the wherein there is absence of presence of intestinal higher the degree of ischemia can be ischemia? → Antibiotics A. Partial Typically NOT warranted in the management of B. Complete simple & non-operative small bowel obstruction. C. Closed loop However, broad-spectrum antibiotics with coverage A. Simple for gram (-) aerobes and anaerobes should be given to all patients set to undergo surgical treatment or V. RATIONALIZATION Laparotomy in those presenting with a complete gut obstruction or strangulated small bowel obstruction. No. RATIONALIZATION → Urgent action Immediate surgical intervention is necessary for 1 CORRECT ANSWER: C. Closed loop patients with bowel strangulation or peritonitis. Closed-loop or complete small bowel obstructions are Strangulated/simple: intramural becomes high enough to cause treated as surgical emergencies. ischemia and eventually necrosis These can lead to bowel ischemia and perforations in 30% of cases and can lead to mortality when surgical Complete: lack of passage of flatus and/or stool management is delayed. Patients with simple obstruction can necessitate a Closed loop: occlusion of proximal and distal part of the surgical laparotomy if the CT scan shows: involved bowel segment ○ No passage of contrast in the colon within 8 hours Source: Batch 2025 Ratio ○ Presence of mesenteric edema/stranding 2 CORRECT ANSWER: C. Complete Intestinal Obstruction ○ Small bowel feces sign Source: Batch 2025 Ratio The patient presents with obstipation for 48 hours which is a clinical feature of complete intestinal obstruction. By definition, 6 CORRECT ANSWER: D. Adenocarcinoma of the duodenum obstipation is the non-passage of flatus (air) and stool or bowel movement within 24 hours. The most common malignancy is Adenocarcinoma: Small bowel adenocarcinoma Source: Batch 2025 Ratio 35%- 50% 3 CORRECT ANSWER: A. No bowel sounds In the small bowel, usually happens in the duodenum Very rare in the jejunum and ileum In performing physical examination of a patient with prolonged Other malignancies of the small intestines: small intestine obstruction, bowel sounds may eventually Carcinoid tumors disappear when bowel motility decreases in prolonged Lymphoma obstruction. Gastrointestinal stromal tumors (GIST): Commonly arise in your Source: MOD6-SURG2-T3-Surgical Disorders of the Small Intestine stomach. If found outside the stomach, most common site is the jejunum 4 CORRECT ANSWER: A. Proximal obstruction A, B and C are wrong as they are examples of other When it comes to acute onset of cramping and abdominal pain: malignancies, but are not the most common primary PROXIMAL OBSTRUCTIONS: Paroxysms of pain malignancy of the small intestines. typically occur at 5-minute intervals Source: Batch 2025 Ratio DISTAL OBSTRUCTIONS: Less frequent abdominal cramping 7 CORRECT ANSWER: A. True Source: MOD6-SURG2-T3-Surgical Disorders of the Small Intestine NASOGASTRIC TUBE (NGT) NGT can help decompress the distended small bowel and minimizes the risk of aspiration The more distended the bowel is, the higher the degree of ischemia Group 4B | Surgical Disorders of the Small Intestine 11 of 11  8 CORRECT ANSWER: B. False IV FLUID RESUSCITATION Restoration of intravascular volume by infusion of isotonic fluid is paramount. Urine output monitoring as well as normalization of vital signs indicate adequacy of fluid resuscitation. Electrolyte imbalances and metabolic acidosis should be corrected as soon as possible, also by giving fluid resuscitation 9 CORRECT ANSWER: A. Advanced Age Advanced age is the correct answer because the patient is already 70 years old. Mortality risk factors: Advanced age American Society of Anesthesiologists Associated Chronic Illness Strangulated obstruction Treatment delay Source: Batch 2025 Ratio 10 CORRECT ANSWER: C. Refer to Surgery for Immediate surgical intervention The symptoms presented by the patient pertain to signs of intestinal obstruction. The common manifestations of small bowel obstruction are continuous abdominal pain with increasing intensity, anorexia, and vomiting. Lack of passage of flatus and/or stool signifies complete bowel obstruction. Immediate surgical intervention is necessary. Source: Batch 2025 Ratio 11 CORRECT ANSWER: D. Simple Source: Lecture video Group 4B | Surgical Disorders of the Small Intestine 12 of 11