Abdominal Surgery Part I (not including acute abdomen) Flashcards
How does overt vers occult GI bleeding differ in presentation?
Overt GI bleeding is visible in the form of hematemesis, melena, and/or hematochezia, whereas occult GI bleeding typically manifests with nonspecific symptoms due to iron deficiency anemia.
Define upper GI bleeding
gastrointestinal bleeding from the esophagus, stomach, or duodenum (proximal to the ligament of Treitz)
A degenerative disorder of gastrointestinal blood vessels that consists of abnormal, dilated, and tortuous communications between veins and capillaries. May be asymptomatic or lead to upper or lower gastrointestinal bleeding.
Angiodysplasia
Gastric mucosal changes including friability and dilated blood vessels that result from portal hypertension. These changes appear as a mosaic or “snake-skin” pattern on endoscopic evaluation. 10-20% of patients may develop acute or chronic bleeding.
Portal hypertensive gastropathy
vomiting blood, which can vary in color from bright red to brown and may resemble coffee grounds, depending on the cause
Hematemesis
Hematemesis is often caused by what kind of GI bleed?
Most commonly caused by UGIB
black, tarry stool with a strong offensive odor
Melena
Melena is often caused by what kind of GI bleed?
Most commonly caused by UGIB
passage of blood through the anus with or without stool
Hematochezia
Hematochezia is often caused by
Most commonly caused by LGIB
Maroon, jellylike traces of blood in stool indicate ___________ bleeding.
colonic
Streaks of fresh blood on stool indicate ___________ bleeding.
rectal
Perforation of a ______________ ulcer is the most common cause of perforation peritonitis.
duodenal
____________ is the preferred imaging modality to confirm the presence of free air within the peritoneal cavity (pneumoperitoneum) and localize the site of the perforated viscus.
CT abdomen with IV contrast
_____________________________ is a bacterial infection of ascitic fluid that occurs in the absence of an identifiable intraabdominal source of infection. It is the most common bacterial infection and a leading cause of hospital admission and mortality among patients with cirrhosis.
Spontaneous bacterial peritonitis (SBP)
Spontaneous bacterial peritonitis (SBP) is often associated with what pathogens?
Enteric gram-negative bacteria (e.g., E. coli, Klebsiella spp.) have historically been the most common isolates; however, gram-positive, fluoroquinolone-resistant, and multidrug-resistant bacteria are increasingly common.
Summ:
Gram-negative enteric bacteria (e.g., Escherichia coli, Klebsiella spp.)
Gram-positive bacteria (e.g., Streptococcus spp., Staphylococcus spp., Enterococcus spp.)
Diagnosis of spontaneous bacterial peritonitis is based on…
Diagnosis is based on the finding of elevated ascitic fluid neutrophil count (≥ 250/mm3) without an intraabdominal surgically-treatable source of infection.
Risk factors for Spontaneous bacterial peritonitis
cirrhosis and ascites
What abx will we consider for spontaneous bacterial peritonitis in a patient with Community-acquired infection AND no recent exposure to broad-spectrum antibiotics ?
First-line: 3rd-generation cephalosporin IV, preferably cefotaxime [2][11][23]
Alternative: oral ofloxacin
What abx will we consider for spontaneous bacterial peritonitis in a patient with Healthcare-associated infection,
suspected resistant pathogen,
AND/OR recent exposure to broad-spectrum antibiotics?
First-line: piperacillin/tazobactam
PLUS one of the following:
Daptomycin if known previous VRE infection or colonization
Vancomycin if known previous MRSA infection or colonization [25]
Alternative for patients with current or recent exposure to piperacillin/tazobactam: meropenem PLUS vancomycin
Consider local resistance patterns and consult infectious diseases for further guidance.
Tarry bowel movements and abdominal pain are consistent with upper GI bleeding (UGIB), likely arising as a complication of peptic ulcer disease (PUD) from NSAID use. Hypotension and tachycardia indicate the development of hypovolemic shock. What is the most appropriate next step in management after inital exam?
Esophagogastroduodenoscopy (EGD) is the preferred next step in the management of UGIB as it allows for bleeding source identification and hemostatic interventions (e.g., cauterization, epinephrine injection). In the case of severe hemorrhaging secondary to PUD, intravenous proton pump inhibitors and blood transfusions can be considered.
Tarry bowel movements and abdominal pain are consistent with upper GI bleeding (UGIB), likely arising as a complication of peptic ulcer disease (PUD) from NSAID use. Esophagogastroduodenoscopy shows no abnormalities.
Next step?
Because the esophagogastroduodenoscopy did not find a hemorrhage in the upper GI tract, the next step in the management of this patient is a colonoscopy to evaluate the lower GI tract. Should the colonoscopy also be normal, the small bowel needs to be examined (e.g., via push enteroscopy, push-and-pull enteroscopy, capsule endoscopy).
What imaging modality/approach do we use to assess melena?
In the context of UGIB, we start with
EGD
nothing on EGD then COlonoscopy
nothing on colonoscopy then enteroscopy
Next step?
Ex lap and peritoneal lavage
A pt with suspected lower GI bleed continues to bleed and remains hemodynamically unstable even after fluid resuscitation. Urgent intervention is required to reliably localize and stop the hemorrhage. What do we do? He had a normal EGD.
Angiography
What is the serum-ascites albumin gradient?
The difference between albumin concentration in ascitic fluid and albumin concentration in the serum. A SAAG >1.1 g/dL indicates that portal hypertension is the likely underlying cause of ascites.
What SAAG indicates that portal hypertension is likely the cause of ascites?
The difference between albumin concentration in ascitic fluid and albumin concentration in the serum. A SAAG >1.1 g/dL indicates that portal hypertension is the likely underlying cause of ascites.
A patient comes in with a SAAG greater than 1.1, fever, abdominal pain, and a peritoneal leukocyte count of 1900/mm3. What is the likely etiology for his presentation?
Bacterial translocation as in Spontaneous bacterial peritonitis. This condition occurs most commonly in patients with portal hypertension and resulting ascites secondary to advanced liver cirrhosis.
In patients with ESRD (end stage renal disease), ∼ 30% of cases of lower GI bleeding are due to __________________-
angiodysplasia.
A degenerative disorder of gastrointestinal blood vessels that consists of abnormal, dilated, and tortuous communications between veins and capillaries. May be asymptomatic or lead to upper or lower gastrointestinal bleeding. ‘arteriovenous malformation’
What is retroperitoneal?
Esophagus, adrenals, kidneys, most of the duodenum, pancreas, aorta, ascending and descending colon, IVC, ureters, rectum
In the setting of blunt abdominal trauma and damage to the retroperitoneal organs, how can you tell the difference in injury to the duodenum versus the pancreas?
Damage to the duodenum results in AIR in the retroperitoneal space versus FLUID in the space
