SESAP ALIMENTARY II Flashcards
Mirizzi syndrome
obstructive jaundice due to extrinsic compression of the common hepatic duct (CHD) caused by a stone impacted in the neck of the gallbladder or cystic duct.
Up to 25% of patients have an increased risk of gallbladder cancer.
Because the stone is characteristically in either the neck of the gallbladder or the cystic duct, previous cholecystectomy does not rule it out as a possible diagnosis
Four factors contribute to development of Mirizzi syndrome:
(1) The cystic duct must be anatomically parallel to the CHD
(2) a stone must become impacted in the cystic duct or gallbladder neck,
(3) the CHD must be obstructed by the stone or by the secondary inflammatory response,
(4) the longstanding obstruction must cause intermittent or constant jaundice with occasional cholangitis.
treatment of Mirizzi syndrome
One study suggested that laparoscopic cholecystectomy can be successful with type 1 Mirizzi syndrome
or
external compression of the CHD by a stone impacted in the cystic duct or Hartmann pouch,
but the authors cautioned that open cholecystectomy is the method of choice for type 2 Mirizzi syndrome, a fistula between the gallbladder and common duct from inflammation and erosion.
Another retrospective study indicated that of 14 patients who underwent laparoscopic surgery, 11 required conversion to an open procedure.
Gastrin is a hormone secreted by
G cells in the gastric antrum.
the action of gastrin
It acts on parietal cells to stimulate hydrochloric acid after ingestion of food.
Patients who have a gastrinoma as their source of uninhibited gastrin secretion usually present with
peptic ulcers secondary to acid hypersecretion.
unopposed gastrin secretion in response to achlorhydria typically occurs in patients with
atrophic gastritis or who take proton pump inhibitors.
Hypergastrinemia occurring with gastritis related to Helicobacter pylori infection is caused by
the decreased somatostatin release by D cells due to increased pH and circulating cytokines around D cells.
Gastric carcinoid tumors also termed
neuroendocrine tumors (NETs),
gastric carcinoid tumors subclassified into 3 distinct groups:
type 1
associated with chronic atrophic gastritis/pernicious anemia (; 70–80%),
type 2
associated with multiple endocrine neoplasia type I (MEN I) Zollinger-Ellison syndrome (ZES; ; 5%),
type 3
sporadic NETs of the stomach ( 15–20%).
treatment of gastric carcinoid tumors
Because type 1 and 2 NETs of the stomach generally pursue an indolent course, tumors smaller than 2 cm (up to 6 in number) should be resected endoscopically, with subsequent interval follow-up.
require more aggressive management, and local surgical resection is recommended:
when greater than 2 cm,
or those with recurrent tumors,
or those with more than 6 tumors generally
type 1 NETs of the stomach arising in the setting of chronic atrophic gastritis, antrectomy may be performed to eliminate the source of gastric production.
Antrectomy results in tumor regression in such cases.
treatment of gastric carcinoid tumors In patients with type 2 NETs of the stomach secondary to ZES/MEN I syndrome,
treatment with somatostatin analogs may be initiated and result in tumor regression.
treatment of sporadic (type III) gastric carcinoid tumors
type 3 isolated sporadic NETs of the stomach requires more aggressive surgery,
partial gastrectomy and lymph node dissection.
associated findings with gastric carcinoid tumor
anemia, hypergastrinemia, and atrophic gastritis consistent with type 1 gastric carcinoid.
5% of patients with pernicious anemia, an autoimmune condition in which antibodies are directed against parietal cells.
The destruction of parietal cell mass results in atrophic gastritis, a loss of acid production, hypergastrinemia, and macrocytic anemia from the loss of intrinsic factor and Vitamin B12 absorption.
Roux-en-Y gastric bypass effects on hormones
ghrelin, glucagon-like peptide-1, and peptide YY that influence eating behaviors and body weight.
Roux-en-Y gastric bypass physiologic effects
fat malabsorption:
After RYGB, the secretion of bile and lipolytic enzymes is reduced, because lipids never pass through the duodenum.
Undigested fat passes into the colon, producing fat malabsorption and steatorrhea.
protein intolerance:
Intolerance of protein-rich foods, such as meat and dairy products, is common. For this reason, many patients fail to meet the daily recommended protein intake, which should average 60–120 g/day.
CCK stimulation and effects
Under physiologic conditions, fat passes into the duodenum and stimulates cholecystokinin (CCK).
CCK stimulates the gallbladder and pancreas to release bile and lipolytic enzymes.
Vitamin deficiencies of Roux-en-Y
iron, Vitamin B12, calcium, Vitamin D, folate (Vitamin B9), and thiamine (Vitamin B1) is recommended.
In addition, iron, calcium, and thiamine are absorbed primarily in the duodenum, which is precluded with RYGB.
Iron stores decline after gastric bypass procedure, making iron-deficient microcytic anemia very common.
Vitamin C supplementation should also be added to increase iron absorption and ferritin levels.
Oral iron supplements can decrease absorption of calcium, magnesium, and zinc, so these should be taken at different times of the day.
RYGB procedure alters the absorption of Vitamin B12 by isolating the source of intrinsic factor, the distal stomach, from the alimentary stream.
However, substantial deficiencies in Vitamin B12 do not occur until at least 1 year after the surgery. Deficiency can result in macrocytic anemia and neuropathy.
calcium deficiency and bone loss.
The loss of fat absorption is believed to contribute to Vitamin D deficiency because it is a fat-soluble vitamin.
This is believed to increase bone turnover and to decrease bone mass. However, calcium deficiency and loss of bone density can occur in the presence of normal Vitamin D and parathyroid hormone (PTH) levels.
An increase in serum PTH levels is indicative of negative calcium balance or Vitamin D deficiency. If deficient, Vitamin D can be supplemented with ergocalciferol or cholecalciferol.
When performing LAR resections for cancer, division of the inferior mesenteric artery (IMA) at its origin from the aorta (high ligation) is often performed to
remove the lymph node basin at risk for metastasis and provide adequate mobilization of the proximal bowel for a tension-free anastomosis.
arterial flow occurs through collateral vessels.
Sudeck point
junction of the colon and rectum
when the LIMA was divided at its origin at the aorta how it is perfusion maintained with descending colon rectal anastomosis
The arc of Riolan
The arc of Riolan
is an inconstant artery
connects the proximal SMA or 1 of its primary branches to the proximal IMA or 1 of its primary branches.
It is classically described as connecting the middle colic branch of the SMA with the left colic branch of the IMA.
It forms a short loop that runs close to the root of the mesentery.
It is an important connection between the SMA and IMA in the setting of arterial occlusion or significant stenosis such as proximal SMA occlusion.
The marginal artery of Drummond is the anastomoses
The marginal artery of Drummond is the anastomoses of the SMA:
the terminal branches of the ileocolic,
right colic,
middle colic arteries
and of the IMA:
left colic
sigmoid branches
These form a continuous arterial circle or arcade along the inner border of the colon known as the marginal artery of Drummond.
The marginal artery is an important connection between the SMA and IMA and provides collateral flow in the event of occlusion or significant stenosis.
The junction of the SMA and IMA territories is at the splenic flexure.
where is the marginal artery of Drummond the weakest
the splenic flexure, hence “the marginal artery” at this point,
known as the Griffiths point
management of esophageal high-grade dysplasia
Observation with proton pump inhibitor therapy is an accepted management strategy.
This requires endoscopy with biopsies every 3–6 months.
This strategy is clearly inferior to radiofrequency ablation.
Antireflux operations, although good for treating the symptoms of gastroesophageal reflux disease, have not been conclusively demonstrated to reduce the cancer risk.
Photodynamic therapy, usually with a light-sensitizing agent such as porfimer sodium, has fallen out of favor due to issues related to buried glands (i.e., islands of Barrett epithelium under a layer of seemingly normal squamous epithelium) and stricture formation.
Esophagectomy was considered an acceptable option because of the high rate of occult carcinoma with high-grade dysplasia. However, given the efficacy of radiofrequency ablation, esophagectomy is reserved for patients in whom the high-grade dysplasia cannot be completely eradicated or in whom other signs increase the suspicion of carcinoma presence. A randomized, sham-controlled trial showed that endoscopic radiofrequency ablation can eradicate Barrett metaplasia and dysplasia and reduce the progression to carcinoma (table 1). It is now considered the primary treatment for Barrett esophagus with high-grade dysplasia in patients without other signs of carcinoma, such as ulceration or nodularity!!!
Small bowel diverticula are categorized by location and type. Location categories include
Location categories include duodenal and jejunoileal.
small bowel diverticuli that are true diverticula how common compared to false diverticula
most common
Duodenal
Meckel diverticula
periampullary diverticula
periampullary
asymptomatic
occasionally they can cause biliary obstruction.
Diverticula of the jejunum and ileum
pulsion diverticula similar to that of the colon.
Although the exact incidence of ileojejunal diverticulosis is unknown, because most of these patients are asymptomatic, it is generally considered far less common than colonic diverticulosis. Most autopsy series place the prevalence of jejunoileal diverticula at approximately 2% or less. The jejunum is a more common site of diverticula than the ileum. The diverticula occur on the mesenteric side of the bowel where the blood vessels enter the bowel from the mesentery. Perforation, bleeding, and obstruction are the most common urgent presentations. Perforation accounts for more than 20% of emergency surgical interventions for jejunoileal diverticula compared with hemorrhage, which accounts for less than 2%. Recurrent abdominal pain is rarely associated with jejunoileal diverticulosis, and weight loss is not likely related to jejunal diverticula.
Bleeding as the presenting sign in colon cancer does what to prognosis
is not associated with worse prognosis,
association between duration of symptoms and colon cancer and survival
none
and there is no association between duration of symptoms and survival in patients with colon cancer.
Patients with intestinal obstruction as their presenting sign of colon cancer
short duration of symptoms with a poorer prognosis.
Peutz–Jeghers syndrome have what present risk of developing colon cancer
how to her overall survival compared to sporadic colon cancer patient’s
pproximately 40% of patients with Peutz–Jeghers syndrome developing colon cancer.
However, these patients are subjected to increased screening compared with the general population. Thus, their cancer is often detected at an earlier stage, resulting in a good prognosis and improved survival rates. at
defect and survival using neoadjuvant chemotherapy versus adjuvant chemotherapy and unresectable pancreatic adenocarcinoma
essentially the same, whether they were given neoadjuvant chemotherapy or were resected followed by adjuvant chemotherapy.
is barely a 2 chemotherapy and radiation therapy improves progression free survival and in unresectable pancreatic adenocarcinoma
yes
A 2009 meta-analysis of chemotherapy for locally advanced and metastatic pancreatic cancer showed improved progression-free survival in patients receiving gemcitabine-based combination therapy, but that improvement was offset by greater toxicity in those patients.
hepatocellular carcinoma Surgical resection is reserved for:
noncirrhotic patients or those with well-preserved liver function and relatively limited tumor burden (ideally a single lesion).
what precludes attempt of primary resection for hepatocellular carcinoma
poor liver function:
Bilirubin values greater than 1.1 mg/dL
cirrhosis:
evidence of portal hypertension (esophageal varices, ascites, thrombocytopenia, portal vein pressure gradient ≥10 mm Hg)
are predictors of postoperative hepatic failure and thus preclude resection.
hepatocellular carcinoma Radiofrequency ablation and alcohol injection are therapies usually reserved for patients who
are not primary surgical resection candidates due to the number or distribution of lesions.
Both of these ablative options are most effective for masses less than 3 cm.
hepatocellular carcinoma chemoembolization
Transarterial embolization (TACE) involves injection of a chemotherapeutic agent, such as doxorubicin or cisplatin, in conjunction with occlusion of the hepatic artery supplying the liver lobe containing the tumor.
This approach is generally used in patients with sufficiently high tumor burden or more advanced cirrhosis to obviate either resection or ablation.
criteria for transplantation with hepatocellular carcinoma
University of California, San Francisco, criteria in 2001 expanded the original 1996 Milan criteria to:
single tumor 6.5 cm or less
or
2–3 lesions 4.5 cm or less,
totaling 8 cm or less,
original Malan criteria:
Less than 5 cm single lesion
3 or fewer lesions less than 3 cm
what can be used to bridge or temporize patient with hepatocellular carcinoma and awaiting transplantation
may benefit from bridging radiofrequency ablation or chemoembolization
recurrence rate with multicentric hepatocellular carcinoma primary resection
Despite the high risk of multicentric recurrence (70% at 5 years),
8 cm hepatocellular carcinoma associated survival rate 5 years with primary resection
primary resection offers the best therapeutic option for this patient, with the potential for a 50% survival rate at 5 years.
octreotide used with a pancreatic leak/fistula
Although somatostatin analogues such as octreotide do decrease fistula output,
Cochrane review does not affect the development of perioperative pancreatitis, postoperative mortality, reoperation rates, or the intensive care unit length of stay.
the
Preoperative intravenous antibiotic therapy before excision of a chronic sinus pilonidal disease
has not been shown to decrease wound complications, improve healing, or affect recurrence!!
pilonidal disease surgical management and relative success rates
Surgical options include complete sinus excision with primary closure or healing by secondary intention, with or without marsupialization of the wound edges. Success of primary closure requires a narrow field of excision and care to avoid sitting in the immediate postoperative period
Sinus recurrence, however, is more frequent after primary closure compared with healing by secondary intension.
previously SESAP question indicated primary closure probably better than advancement flap
serum albumin and serum transferrin predictive of an increased risk of morbidity and mortality at the time of esophageal resection
serum albumin less than 3.0 mg/dL and a serum transferrin less than 18 g/dL are predictive of an increased risk of morbidity and mortality at the time of esophageal resection.
