EOR GI part 4- gastric CA, bariatric surgery, SBO Flashcards
What are the associated RFs of gastric CA- diet?
Smoked meats High nitrates Low fruits and veggies EtOH Tobacco
RFs of gastric CA- environmental
Raised in high-risk area Poor SES Atrophic gastritis Male gender Blood type A Previous partial gastrectomy Pernicious anemia Polyps H. pylori
Which blood type is associated with gastric CA?
Blood type A
What are the sx of gastric CA?
Weight loss Emesis Anorexia Pain/epigastric discomfort Obstruction Nausea
What is a Blumer’s shelf?
Solid peritoneal deposit anterior to rectum, forming a “shelf”, palpated on rectal exam
What is a Virchow’s node?
Metastatic gastric CA to the nodes in the left supraclavicular fossa
What is a surveillance lab finding in gastric CA?
CEA elevated in 30% of cases (if pos, useful for post-op surveillance)
What is the initial workup for gastric CA?
EGD with bx Endoscopic u/s to evaluate the level of invasion CT abdomen/pelvis for metastasis CXR Labs
What is the histology of gastric CA?
Adenocarcinoma
What is the DDx for gastric tumors?
Adenocarcinoma Leiomyoma Leiomyosarcoma Lymphoma Carcinoid Ectopic pancreatic tissue Gastrinoma Benign gastric ulcer Polyp
Which morphologic type of gastric CA is named after a “leather bottle”?
Linitis plastica- the entire stomach is involved and looks thickened (10% of cancers)
Which pts with gastric CA are non-operative?
Distant metastasis
Peritoneal implants
What is the role of laparoscopy in gastric CA?
To r/o peritoneal implants and to evaluate for liver metastasis
What is the genetic alteration seen in >50% of pts with gastric CA?
P53
What is the tx for gastric CA?
Surgical resection with wide (>5 cm checked for frozen section) margins and lymph node dissection
What operation is performed for a tumor in the antrum?
Distal subtotal gastrectomy
What operation is performed for a tumor in the midbody?
Total gastrectomy
What operation is performed for a tumor in the proximal?
Total gastrectomy
What is a subtotal gastrectomy?
75% of the stomach removed
What is a total gastrectomy?
Stomach is removed and a Roux-en-Y limb is sewn to the esophagus
When should splenectomy be performed in gastric CA?
When the tumor directly invades the spleen/splenic hilum or with splenic hilar adenopathy
What is the adjuvant tx for gastric CA?
Stages II and III: post-op chemo and radiation
Define morbid obesity
BMI >40
OR
BMI >35 with a medical problem related to morbid obesity
What medical conditions are associated with morbid obesity?
Sleep apnea Coronary artery dz Pulm dz DM Venous stasis ulcers Arthritis Infections Sex-hormone abnormalities HTN Breast CA Colon CA
What are the current best options for bariatric surgery?
Sleeve gastrectomy
Gastric bypass (malabsorptive)
Vertical-banded gastroplasty
Gastric bypass
Stapling off of small gastric pouch (restrictive)
Roux-en-Y limb to gastric pouch (bypass)
How does gastric bypass work?
Creates a small gastric reservoir
Causes dumping sx when a pt eats too much food or high-calorie foods; the food is “dumped” into the Roux-en-Y limb
Bypass of small bowel by Roux-en-Y limb
What is the MC sign of an anastomotic leak after a gastric bypass?
Tachycardia
What is a LAP-BAND?
Laparoscopically placed band around stomach with a subcutaneous port to adjust constriction; results in smaller gastric reservoir
What is a Petersen’s hernia?
Seen after bariatric gastric bypass- internal herniation of small bowel through the mesenteric defect from the Roux-en-Y limb
What is small bowel obstruction?
Mechanical obstruction to the passage of intraluminal contents
What are the S/sx of SBO?
Abdominal discomfort Cramping Nausea Abdominal distention Emesis High-pitched bowel signs
What lab tests are performed with SBO?
Electrolytes
CBC
Type and screen
UA
What are classic electrolyte/acid-base findings with proximal SBO?
Hypovolemic, hypochloremic, hypokalemia, alkalosis
What must be r/o on PE in pts with SBO?
Incarcerated hernia (also look for surgical scars)
What major AXR findings are associated with SBO?
Distended loops of small bowel air-fluid levels on upright film
Define complete SBO
Complete obstruction of the lumen
What is the danger of complete SBO?
Closed loop strangulation of the bowel leading to bowel necrosis
Define partial SBO
Incomplete SBO
What is initial management of all pts with SBO?
NPO
NGT
IVF
Foley
What tests can differentiate partial from complete SBO?
CT with PO contrast
What are the ABCs of SBO?
Causes:
Adhesions
Bulge (hernias)
CA and tumors
What is SMA syndrome?
Seen with wt loss- SMA compresses duodenum, causing obstruction
What is the tx of complete SBO?
Laparotomy and lysis of adhesions (LOA)
What is the tx of incomplete SBO?
Initially, conservative tx with close observation plus NGT decompression
Intraoperatively, how can the level of obstruction be determined in pts with SBO?
Transition from dilated bowel proximal to the decompressed bowel distal to the obstruction
Can a pt have complete SBO and bowel movements and flatus?
Yes; the bowel distal to the obstruction can clear out gas and stool
After a small bowel resection, why should the mesenteric defect always be closed?
To prevent an internal hernia
What may cause SBO if pt is on Coumadin?
Bowel wall hematoma
What is the #1 cause of SBO in adults (industrialized nations)
Postop adhesions
