Abdominal Pain Flashcards
Small bowel obstruction
- Etiologies: Adhesions (most common in people who have had ABD surgery before), hernias (most common in people who have not)
- Clinical presentation: Obstipation (key sign), colicky pain (as peristalsis hits obstruction, hurts), borborygmi, abdominal distension
- Dx: Upright abdominal film / KUB (looking for air-fluid levels), follow-up CT scan w/ oral contrast
- If contrast material makes it to rectum: incomplete obstruction. If not: complete obstruction
- Tx:
- If incomplete OR complete but poor surgical candidate: Conservative management (NG tube decompression, fluid and electrolyte management, IV sugars)
- If complete OR failure of above: Urgent surgery
- If signs of peritonitis at presentation or anywhere above: Emergent surgery
Obstipation
Severe form of constipation in which a person cannot pass any stool or gass
Obstipation is to constipation as anuria is to oliguria
Direct hernias
- Most common in adult males
- Go directly through transversalis muscle in the inguinal region, not usually to scrotum but sometimes
Indirect hernias
- Most common in baby males
- Goes through inguinal ring
- End up w/ intestines in scrotum – inguinal hernia
Femoral hernias
- Most common in females
- Go under inguinal ligament
Ventral hernias
- Iatrogenic
- Failure of hernia to close in post-operative patient
Features of an incarcerated hernia
Not redudible, may be painful when surrounding muscle contracts
May progress to strangulated hernia
3 major types of hernias (in terms of gut mobility) and management
- Reducible (elective surgery)
- Incarcerated (urgent surgery)
- Strangulated (emergent surgery)
Features of a strangulated hernia
- Irreducible
- Painful
- Peritoneal signs (peritonitis, guarding, maybe rebound, maybe fever/leukocytosis)
Etiologies of appendicitis
- Usually caused by formation of a fecalith (poop rock) that gets stuck in the appendix, compresses, and causes ischemia
- Pinworms
- Undigested seeds
- Lymphoid hyperplasia
- External strangulation
Most common abscesses associated with ruptured appendix
- Para-appendiceal
- Sub-phrenic
Imaging for appendicitis
NOT NEEDED when the presentation is clear
In real life, the CT will usually be done to confirm while surgery is consulted and working up the patient. This is more of a logistics thing than a medicine thing, it is just convenient to have, but it is not strictly necessary and will not be the correct “next step” on the exam.
Carcinoid syndrome
-
Unless the tumor has metastasized to the liver, there will not be systemic signs of disease.
- This is because serotonin produced in portal circulation is metabolized. So, it can only make it to systemic circulation and cause symptoms if it is in the liver or lungs (some point beyond the portal system)
- Sx: Flushing, wheezing, diarrhea, sometimes R sided cardiac fibrosis
- Dx: Check urine for 5-HIAA. CT for staging if 5-HIAA is positive.
- Tx: Resect tumors.
Positional pain in pancreatitis
Laying back/stretching the thorax -> stretching the precordium -> pancreas irritated
Leaning forward/flexing thorax -> less stress on precordium -> pancreas less irritated
When is lipase considered pancreatitis-range?
>3x upper limit of normal
Pancreatitis (non-necrotizing) Dx and Tx
- Dx:
- First, check lipase. If they are elevated, done. It’s pancreatitis. No need for imaging..
- If lipase is not elevated or equivocal, do a CT to look for imaging evidence of pancreatitis. If SIRS, abscess, or necrotizing pancreatitis are suspected or if the patient is not improving on conservative management, then do a CT.
- Once pancreatitis is confirmed, begin Tx. However, the next day/after Tx is started, you want to start looking for etiologies. For this: RUQ US and triglycerides.
- Tx:
- Keep patient NPO
- IV fluids, sugar
- Pain meds
When should you suspect abscess in pancreatitis?
When the patient is on conservative management, but is not improving for 5-7 days and appears actively septic with fevers and leukocytosis.
In this case, do a CT scan to search for abscess.
Presentation of pancreatic pseudocyst
Couple of weeks out from pancreatitis. Follow-up appointment is scheduled.
But then, patient begins to notice early satiety, weight loss, and new abdominal pain.
In this case, do a CT to search for a pseudocyst.
- Tx:
- If around for < 6 weeks AND < 6 cm, it is uncomplicated. Watch + wait. Get a CT at the end of 6 weeks to see if it is resolving.
- If > 6 weeks OR > 6 cm, it is complicated (high probability of infection). Needs to be drained (not necessarily surgically, just somehow).
Necrotizing pancreatitis Dx and Tx
- Dx: Person presents with pancreatitis and SIRS-like symptoms or develops SIRS-like symptoms. Do a CT which shows calficiations in the pancreas. Consider FNA of necrotizing tissue to screen for infection if clinical situation indicates.
- Tx: ICU management, necrotectomy when pancreas is fully necrotized (not immediate).
- Carbapenem abx IF: FNA from biopsy proving infection
Surgery for chronic pancreatitis
NOT DONE.
We do not operate on chronic pancreatitis. Removing it only makes it worse, does not improve the pain. DO NOT OPERATE.
Obstructive-type abdominal pain
- Colicky, no fever, no leukocytosis
- Nonpositional
- Examples: Nephrolithiasis, cholelithiasis, small bowel obstruction
Inflammatory type abdominal pain
- Constant, fever, leukocytosis
- Nonpositional
- Examples: Cholecystitis, pyelonephritis
Peritoneal-type abdominal pain
- “Sick as shit,” constant pain
- Motion is very painful
- X-ray shows free air
- Examples: Perforated peptic ulcer, perforated appendix, cancer, perforating trauma
Ischemic pain
- Pain “out of proportion to symptoms/exam”
- Writhing in pain, exquistitely tender abdomen
- May have currant jelly bowel movements or florent sepsis
- Risk factors: CAD, Afib
- Exmaple: Mesenteric ischemia
Always consider ___ as potential etiologies of epigastric pain
Always consider mediastinal processes as potential etiologies of epigastric pain
Cardiac processes, aortic processes, esophageal processes, mediastinitis.
Best initial test by location of abdominal pain
RUQ: RUQ US
Anywhere else: CT scan
Presentation of mestenteric adenitis
Following viremia. Typically in pediatric patients.
Classic presentation is ~2 weeks following a viral sore throat.
Often RLQ pain or diffusely lower abdominal. May have associated diarrhea.
Visceral pain pattern
Pattern of ruptured peptic ulcer pain
With a perforated peptic ulcer, pain almost always begins in the epigastrium, but as leaked gastric contents track down the right paracolic gutter, pain may descend and become prominent in the right lower quadrant.
Sharp, superficial, constant pain due to peritoneal irritation (often presenting as focal peritonitis) is typical of:
- Ruptured peptic ulcer
- Ruptured appendix
- Ovarian cyst
- Ectopic pregnancy
Intermittent, crampy pain (colic) may occur for short or long periods but is punctuated by pain-free intervals and is most characteristic of ___
Intermittent, crampy pain (colic) may occur for short or long periods but is punctuated by pain-free intervals and is most characteristic of obstruction of a hollow viscus.
Pain of small bowel obstruction
Usually intermittent, vague, deep- seated, and crescendo at first, but becomes sharper, unremitting, and better localized with time
Unlike the disquieting but bearable pain associated with bowel obstruction, pain caused by ___ rapidly becomes unbearably intense.
Unlike the disquieting but bearable pain associated with bowel obstruction, pain caused by lesions occluding smaller conduits (bile ducts, uterine tubes, and ureters) rapidly becomes unbearably intense.
Abdominal pain ddx by pain character and location
Intense abdominal pain that is hardly assuaged even by high potency narcotics
Characteristic of ischemic pain from ischemic bowel or mesenteric thrombosis
Gas stoppage sign
When a patient denies pain but complains of a vague feeling of abdominal fullness that feels as though it might be relieved by a bowel movement
Due to reflex ileus induced by an inflammatory lesion walled off from the free peritoneal cavity, as in retrocecal appendicitis
Vomiting in medical vs surgical conditions
Pain in the acute surgical abdomen usually precedes vomiting, whereas the reverse holds true in medical conditions
This is due to the differential mechanisms. When sufficiently stimulated by secondary visceral afferent fibers, the medullary vomiting centers activate efferent fibers to induce reflex vomiting
Bump tenderness sign
Bump tenderness over the lower costal ribs indicates an inflammatory condition affecting the diaphragm, liver, spleen, or its adjacent structures
Kehr sign
Left shoulder pain associated with hemoperitoneum or other irritants in the peritoneal space
A classic sign of ruptured spleen
Tests to order for EVERY case of acute abdomen
- Blood studies
- Urinalysis
Anorectal abscess
- Etiology: Blockage of glandular lumen, subsequent infection
- Presentation: Acute rectal pain, swelling, fever, sometimes pus or mucus drainage.
- Exam: L/R perirectal asymmetry, area of fluctuance (only if abscess is low, otherwise require MRI or EUA)
- Classified by location: perianal, ischiorectal, intersphincteric, and supralevator.
- Most are perianal or ischiorectal and can be easily identified on exam
- Intersphincteric or supralevator may require MRI or EUA (exam under anesthesia) for diagnosis
- Tx: Incision and drainage
- Complications: Recurrence, anal fistula formation
- Very common. Patients should be warned and told to followup.
Anal fistulas
- Etiology: May be related to predisposing condition (Crohn’s) or to prior injury/surgery (often anorectal abscess drainage)
- Presentation: Anal purulent drainage 6-8 weeks following abscess drainage
- Any nonhealing anal wound should be presumed a fistula until proven otherwise
- Classified by location in relation to sphincters: intersphincteric, transsphincteric, suprasphincteric, and extrasphincteric
- Due to the frequency of the abscesses that created them, intersphincteric and transsphincteric fistulas are the most common
- Dx: MRI. Transanal ultrasound may also be useful.
- Tx:
- For fistulas not involving the sphincter: Fistulotomy
- For fistulas involving the sphincter: Seton placement, then 3 months later, fibrin glue or, anal fistula plug. If these fail, repeat or try the LIFT (ligation of the intersphincteric fistula tract) procedure. If this fails, rectal advancement flap.
- Complications: Fectal incontinence
Ddx for anal abscess and fistula
- Perianal hidradenitis
- Pilonidal disease
- Bartholin’s gland cyst
Communication of an anal abscess and its etiology
- Points of communication of an abscess assessed on imaging or in the OR can hint to its etiology
- If it communicates only with the skin, hidradenitis may be the etiology
- If it communicates only with the midline gluteal cleft, it may be pilonidal in origin
- If it communicates with the anus, it is probably due to an associated fistula
Recurrent anorectal abscess or anal fistulas should make you suspect. . .
. . . Crohn’s disease
Treating intersphincteric and supralevator abscesses
Can’t be treated superficially by surgeons due to their depth, unlike the more common superficial abscesses.
Intersphincteric: Transanal
Supralevator: Transanal or interventional radiology
Who gets antibiotic ppx for anorectal abscess drainage?
-
Preoperatively, only patients in whom you are worried about endocarditis:
- Hx endocarditis
- Prosthetic valve
- Congenital heart disease
- Hx heart transplant
- Postoperatively, only immunocompromised patients
All SBO is divided into two categories:
- Mechanical obstruction
- Paralytic ileus
Mechanical obstruction is broken down into:
- Simple obstruction
- Strangulation (ischemia involved)
Three most common etiologies of mechanical SBO
- Adhesions
- Hernia
- Malignancy
Hernia exam for suspected SBO
- Hernia is the most common etiology of SBO in a patient without a history of prior abdominal surgery
- Most likely sites are:
- Inguinal
- Femoral
- Umbilical
- Less likely internal hernia sites:
- Foramen of Winslow (entrance to the lesser sac)
- Obturator foramen
Bezoar
A bezoar is a tightly packed collection of partially digested or undigested material that most commonly occurs in the stomach. Gastric bezoars can occur in all age groups and often occur in patients with behavior disorders, abnormal gastric emptying, or altered gastrointestinal anatomy.
Feculent emesis in SBO
- More likely with distal SBO
- This is beause it is due to the bacteria growing proximally from the point of obstruction
Systemic symptoms in SBO
- Do not necessarily indicate ischemia
- Bacteria may translocate from the collection on the proximal side of the obstruction to the MLNs, and then to the circulation
SBO symptoms by location
Distinguishing simple obstruction from strangulation in SBO
In strangulation, there will certainly be a fever and there will very likely be peritonitis
Peristaltic rush
“Tinkling” bowel sounds heard in early small bowel obstruction. Progressively decrease over time, so they may not be present if the patient has had SBO for a while
Imaging studies in SBO
- X-ray can confirm clinical diagnosis (“Ladder” sign, multiple air-fluid levels)
- CT with oral or IV contrast is more useful. Helps determine the etiology and fat stranding can point to ischemic areas.
-
Gastrografin should be performed at 48 hours of conservative treatment for diagnostic and therapeutic purposes.
- Lack of Gastrografin progression into the colon with 24 hours predicts the need for surgery in about 96% of cases.
Intestinal pseudo-obstruction
- If colonic, risk of cecal perforation
- Ddx for intestinal:
- scleroderma,
- myxedema,
- lupus erythematosus,
- amyloidosis,
- drug abuse (phenothiazine ingestion),
- radiation injury,
- progressive systemic sclerosis
- CMV infection
- EBV infection
Ogilvie syndrome
An ileus, not a true obstruction! Treat w/ conservative measures. If this does not yield improvement, neostigmine may be used. Not a surgical problem.
Diagnostic peritoneal lavage interpretation
- Positive is defined as any one of:
- >10 mL of aspirated blood
- Presence of bilious contents during aspiration
- >100,000 RBC/mL
- >500 WBC/mL
Main risk factors for hepatocellular adenoma
- Use of oral contraceptives containing estrogen
- Pregnancy
- Anabolic steroid use
Main types of benign liver cyst
- Hepatic hemangioma
- Focal nodular hyperplasia
- Hepatocellular adenoma
“Hydatid” liver cyst
Caused by echinococcus
Hormone-responsive benign liver tumors
Both hepatic hemangioma and hepatocellular adenoma seem to be somewhat sensitive to estrogen
Diagnostic workup for suspected liver mass
- Ultrasound (to detect)
- Contrast CT or MRI (to help characterize lesion)
-
Biopsy
- HOWEVER, you cannot biopsy hemangiomas, as they will bleed like crazy
Treatment for benign liver tumors
- Hepatic hemangioma and focal nodular hyperplasia: Conservative management
- Hepatocellular adenoma:
- Discontinue oral contraceptives
- Women with symptoms or tumor > 5 cm: indication for surgical resection because of increased risk of rupture, bleeding, or malignant transformation
- Men with hepatocellular adenoma: indication for surgical resection irrespective of the size of the lesion because of an increased risk of malignant transformation
Follow-up for benign liver tumors
- Hepatic hemaognioma: Regular follow-up
- FNH: Ultrasound every 6 months for first 3 years after Dx
- Hepatocellular adenoma: CT or MRI at 6-12 month intervals
The typical clinical picture of a hepatocellular adenoma
a young woman with a history of oral contraceptive or anabolic steroid use and upper right abdominal pain.
Differentiating the benign liver tumors
Congenital polycystic liver likely indicates. . .
. . . ADPKD
Remember, ADPKD involes both kidney AND liver cysts. We just focus on the kidney since it impairs kidney function more significantly.
Characteristics of a simple hepatic cyst
- Epidemiology: Peak incidence > 50 yrs
- Clinical: Usually asymptomatic. Some with large cysts may have dull RUQ pain, bloating, early satiety
- Dx:
- Ultrasound: anechoic, round lesion with dorsal acoustic enhancement
- CT: well-delimited lesion; shows no contrast enhancement
- Treatment: laparoscopic resection if symptomatic
Risk factors for hepatocellular carcinoma
- Pre-existing cirrhosis or chronic hepatitis
- Age > 70
- More common in men
In patients with cirrhosis of the liver or chronic hepatitis B/C infection, ___ is used as a screening test for HCC
In patients with cirrhosis of the liver or chronic hepatitis B/C infection, AFP is used as a screening test for HCC
Pathway for HCC diagnosis
- Screen at-risk patients with AFP
- If positive or if consistent symptoms, ultrasound is the next step, followed by confirmatory abdominal CT or MRI.
- ONLY if both AFP and imaging are negative and we still think there might be HCC will we biopsy (since biopsy has a risk of severe bleed)
Two main causes of Budd-Chiari syndrome
- Polycythemia vera
- Hepatocellular carcinoma
“Daughter cysts” in the liver
Buzz word for echinococcus
Treat w/ albendazole and PAIR if necessary
PAIR procedure
- Puncture, aspiration, injection, reabsorption procedure
- Done for treatment of echinococcus-induced hydatid cysts, always in combination with albendazole or equivalent antihelminthic
- Cysts contain many highly antigenic molecules and may cause anaphylaxis when they rupture or may seed a secondary infection
Treatment of alveolar echinococcosis
- Curative resection followed by at least 2 years of treatment with albendazole to prevent a potential relapse
- Palliative care if surgery is not possible or unsuccessful – still treat w/ albendazole
- Follow-up for at least 10 years
Risk factors and diagnosis for echinococcosis
- Risk factors:
- Dog, cat, fox fur exposure
- Dirt contaminated by animal faeces (dog poop)
- Fecal-contaminated food or water (wild berries, wild mushrooms)
- Dx: With ELISA for antigens. False negatives are common.
- Imaging: egg-shell calficiations in the wall of a hydatid cyst on ultrasound are common
IgG4-associated cholangitis
- Almost always associated with concurrent autoimmune pancreatitis
Subacute onset severe RUQ pain, elevated liver labs, one or more cysts on liver US
Hepatic abscess
Pneumobilia
- Air in the bile tree
- Indicative of sphincterotomy of the sphincter of Oddi, biliary-enteric anastomosis, and gallstone ileus.
What SBO looks like on CT
When SBO pain goes from being colicky to being constant, it raises concern for. . .
. . . persistent bowel ischemia or severe bowel distension
This is similar to the difference between colicky gallbladder pain and constant gallbladder pain. Colicky only occurs with peristalsis. If there is constant pain, something else is going on.
The vicious cycle of bowel distension in SBO
As the bowel gets more distended, there is more venous congestion. As there is more venous congestion, there is more edema, which increases the distension and obstruction.
Eventually, the result is ischemia and necrosis.
Early post-operative SBO
- < 30 days from abdominal surgery
- Usually due to adhesions, but since the adhesions are ‘immature’ and poorly organized, there is a low likelihood of bowel strangulation
- Thus, these cases can almost always be treated conservatively with NPO, NG tube decompression, and fluids alone – no need for surgery
Closed loop bowel obstruction
When there are *two* obstructions that wall-off a segment of bowel
Examples: Small bowel loop incarceration in a tight hernia defect, intestinal volvulus, tight adhesive band obstruction in two areas
These cases are unlikely to resolve without surgical intervention
Gallstone ileus
- SBO from a large gallstone which forms within the bowel
- Typically happens within the setting of cholecysto-duodenal fistula
- Thus, pneumobilia is an associated finding
- ~15% of patients with gallstone ileus may have a second gallstone in the GI tract. Therefore, the entire small bowel should be examined during the operation for gallstone ileus.
Gastrografin challenge in SBO
- Diagnostic and therapeutic maneuver-ube. Since it is hyperosmolar, it causes shift of fluid from the bowel wall into the lumen, reducing local edema at the site of obstruction. This promotes resolution of the obstruction.
- Works especially well for SBO related to adhesions
- An option for patients deemed appropriate for nonoperative management
Most common SBO etiologies in adults
- Postoperative adhesions
- Hernias
- Malignancies
- Crohn’s
- Gallstone ileus
Most common SBO etiologies in neonates
- Hernias
- Malrotation-volvulus
- Meconium ileus
- Meckel diverticulum
- Intusussception
- Intestinal atresia
Patients with SBO tend to describe ___ while patients with ileus tend to describe ___
Patients with SBO tend to describe cramp-like pain while patients with ileus tend to describe constipation and distension
The best initial test for SBO is ___, but ___
The best initial test for SBO is CT scan, but you have to give fluids first to prevent contrast-induced nephropathy (since they are probably going to come in dehydrated).
CT scan is more specific for SBO, and can differentiate SBO from ileus by the presence or absence of a transition point
Swirl sign / whirlpool sign
- Seen on CT, indicative of a volvulus
- Seen when the bowel rotates around its mesentery leading to whirls of the mesenteric vessels.
Alvarado score
- 1-4: Low probability of appendicitis. Treat with antibiotics.
- 5-6: Compatible with appendicitis.
- 7-8: Probably appendicitis.
- 9-10: Highly likely appendicitis. Proceed to surgery without need for further imaging.
Post-op antibiotics for appendicitis
- Done for perforated appendicitis or gangrenous appendicitis
- 5-7 day course
- Reduces risk of intra-abdominal abscess following surgery
The first-step in the workup of suspected pyelonephritis (after urinalysis) is. . .
. . . CT scan
This is to rule out the presence of any stones. Stones may cause or be a risk factor for pyelonephritis, or may mimic pyelonephritis in the absence of true renal pelvis inflammation.
Opinion of the surgical community on interval appendectomy
Kind of ambivalent. Some prefer a wait and see approach, some prefer a routine appendectomy approach.
In general we tend to be on the side of not over-treating, so not everyone necessarily needs an interval appendectomy following resolution of appendicitis with abx.
Appendicitis can present many ways, but it should not present with ___ pain
Appendicitis can present many ways, but it should not present with colicky pain
The appendix does not peristalse. If pain is colicky, this is a pretty decent sign that you are not looking at appendicitis.
“urge to defecate”
Another component of the classic appendicitis presentation
Treatment of uncomplicated diverticulitis
Just antibiotics. Outpatient is as effective as inpatient.
Quinolone + metronidazole OR amox-clav
Treatment options for recurrent diverticulitis
- Prophylaxis:
- Rifaximin + fiber (improves symptoms)
- Mesalazine (reduces risk)
- Probiotics (reduces risk)
- Prophylactic colectomy (reduces risk)
Why do we often do colostomy and delayed rectal anastamosis rather than primary rectal anastamosis?
Because primary rectal anastamosis of an inflamed colon is likely to lead to anastamotic complications
Most common etiology of colonic fistula
Diverticulitis
Feculent vomiting
Looks like stool/fecal matter in vomit, halitosis
Indicative of stagnant material in the intestinal tract. Suspicious for bowel obstruction or ileus.
Peyer’s patch hypertrophy
May cause insussusception post-virally in kiddos
Treating intusussception in a kiddo vs adult
Both you can possibly give contrast enema
If that doesn’t work in a kid, you push on inferior side to try and reduce.
If in an adult, you resect.
This is because disease in a kid is likely due to Peyer’s patch and in an adult is likely due to cancer.
Coffee bean sign
Lactate in volvulus
A volvulus by definition separates a segment of circulation
So. . . the lactate can’t make it out! It will never see systemic circulation.
If a volvulus holds obviously dead bowel. . .
. . DON’T UNTWIST IT. It is full of inflammatory, vasoactive mediators, and potassium.
You will precipitate sepsis or arrythmias
Diagnosing Meckel’s diverticulum
Technetium-99 scan is necessary
Diagnostic test for appendicitis in children and pregnant women
Ultrasound is the preferred imaging modality, if imaging is necessary
Contained perforated appendix
If a patient comes to the hospital after ~5 days of appendicitis and is generally stable and non-peritoneal, the appendix may have perforated and resulted in a contained, walled-off abscess. This can be confirmed by demonstrating peri-appendiceal fluid on CT scan.
In this case, conservative management followed by elective appendectomy in ~6-8 weeks is the therapy of choice.
Sigmoid diverticulitis is often accompanied by. . .
. . . bladder symptoms and sterile pyuria
Ruptured ovarian cyst presenting with peritonitis
- Ruptured ovarian cysts can actually cause substantial intraperitoneal hemorrhage, pertonitis, and referred shoulder pain in severe cases
- Occurs following strenuous or sexual activity.
Treatment of sigmoid volvulus
- First-line: Detorsion with flexible sigmoidoscopy
- If this succeeds, follow with elective sigmoidectomy
- Second line: If detorsion fails, emergency sigmoid colectomy IF peritonitis or perforation is present
