Abdominal Pain LSU Medical Student Clerkship, New Orleans, LA

Historical Elements O- onset P-provocation /palliation Q- quality/quantity R- region/radiation S- severity/scale T- timing/time of onset

Physical Exam General Appearance and Vitals (sick vs Not sick) Abdominal exam -Inspection (scars, masses, ecchymosis, distention) -Auscultation (bowel sounds, bruits), -Percussion (organomegaly, dullness) -Palpation (tenderness, guarding, rebound, referred pain, masses) -Don't forget GU, Rectal and Pelvic

Visceral Pain Stretching of hollow viscus or capsule of solid viscus Visceral fibers enter the spinal cord at several levels leading to poorly localized, poorly characterized pain. (dull, cramping, aching)

Visceral Pain Visceral pain can be localized by the sensory cortex to an approximate spinal cord level determined by the embryologic origin of the organ involved. Foregut organs (stomach, duodenum, biliary tract) produce pain in the epigastric region Midgut organs (most small bowel, appendix, cecum) cause periumbilical pain Hindgut organs (most of colon, including sigmoid) as well as the intraperitoneal portions of the genitourinary tract cause pain initially in the suprapubic or hypogastric area.

Parietal Pain Parietal abdominal pain is caused by irritation of fibers that innervate the parietal peritoneum Parietal pain, in contrast to visceral pain, can be localized to the dermatome superficial to the site of the painful stimulus. As the underlying disease process evolves, the symptoms of visceral pain give way to the signs of parietal pain, causing tenderness and guarding. As localized peritonitis develops further, rigidity and rebound appear.

Referred Pain Pain or discomfort that is perceived at a site distant from the affected organ because of overlapping transmission pathways Also reflects embryologic origin: subdiaphragmatic irritation -> ipsilateral supraclavicular or shoulder pain gynecologic pathology -> back or proximal lower extremity pain biliary tract disease -> right infrascapular pain myocardial ischemia ->midepigastric, neck, jaw, or upper extremity pain ureteral obstruction -> ipsilateral testicular pain

Radiology: Plain Films Advantages: Quick, easy, non-invasive, lower radiation, lower cost, can be done at bedside and can help make decisions in certain disease states. Disadvantages: Only useful in certain conditions – otherwise low yield, difficult to position sick patients.

Radiology: Plain Films When are they useful? Obstruction/Ileus Volvulus (cecal and sigmoid) Free air Radiopaque foreign bodies Constipation?

Plain Films: Small bowel obstruction

Cecal Volvulus and Sigmoid Volvulus

Pneumoperitoneum

Iron Overdose: BAT CHIPS: Remember the radiopaque foreign bodies mneumonic: BAT CHIPS: Barium Antihistamines Tricyclic antidepressants Chloral hydrate, calcium, cocaine Heavy metals Iodine Phenothiazine, potassium Slow-release (enteric coated)

Radiology: Ultrasound Advantages: Can be done at bedside, easy to learn, repeatable, no radiation, cheap, can be used in pregnancy, patient does not need to leave the department Disadvantages: Highly dependent on user’s skill level. Limited by body habitus and bowel gas

Radiology: Ultrasound What conditions is it most useful for? Gallbladder disease AAA Hydronephrosis Volume status Ob/Gyn (Ectopic, IUP, Ovarian pathology) Appendicitis (particularly in children)

Ultrasound: Cholecystitis

Ultrasound: AAA

Ultrasound: Appendicitis

Radiology: CT Advantages: Highly diagnostic for most disease processes. High yield exam. Helpful with multiple, competing diagnoses. Disadvantages: Time. Cost. Radiation. Contrast exposure (for IV contrast). Patient should be stable to go to CT.

Laboratory: The labs you order should be used confirm or exclude specific diagnoses suspected by your history and physical examination. CBC, CMP, Amylase, Lipase and UA are routinely ordered as “belly labs” but should not be ordered blindly. The studies you obtain (labs and imaging) should be ordered with the intention of changing your management of the patient. They should not be ordered “just because the patient is in the ED.”

Cases… A 60 y/o male presents after a syncopal event with a complaint of abdominal pain. His pain is poorly localized but radiating to his back. His history is significant for HTN and tobacco abuse. His vitals are normal and his physical exam reveals only the following:

What is on the differential? Pancreatitis Mesenteric Ischemia MI Gallbladder Disease GERD Obstruction Peritonitis PE PUD AAA Valvular Insufficiency Perforated Viscus

Abdominal Aortic Aneurysm What happens: The media weakens over time, the vessel dilates and expands over time. As the vessel weakens and expands, rupture becomes more likely. The larger it becomes, the more likely is the rupture.

AAA Fun facts: They are typically infrarenal >3cm at this level is a AAA Age, Family history, Atherosclerotic risk factors, infection, trauma, connective tissue disease are risk factors. Rupture is associated with 80-90% mortality. Vital signs can be normal. For now.

AAA: Diagnosis and Management H&P: May not be symptomatic until the rupture Syncope and Abdominal pain Cullen’s sign and Grey Turner’s sign Imaging: U/S 100% sensitive when the aorta is visualized. CT requires a stable patient but is also highly sensitive and is better at detecting rupture and retroperitoneal fluid. Treatment is surgical!! Despite what surgery tells you: There is no such thing as a stable rupture. ED’s role is maintaining hemodynamic stability with blood products – SBP 90-100mg until surgery.

CT of Rupturing AAA:

Cases… A 75 year old male presents with diffuse, severe abdominal pain after having a bloody bowel movement. His history is significant for A. Fib and CHF. His vitals show hypotension and tachycardia. You palpate a soft abdomen but even the lightest touch causes him extreme pain. You stabilize him and send him to the CT… film…

Differential? Lower GI Bleed Brisk Upper GI bleed Mesenteric Ischemia Peritonitis Diverticulitis Aorto-enteric Fistula Small Bowel Obstruction Large Bowel Obstruction

Selections from “Diffuse pain”: Mesenteric Ischemia What happens: Most commonly from emboli but can be from thrombus or low-flow state to mesenteric vasculature which leads to ischemia of the bowel. Death of bowel leads to bacterial translocation which leads to peritonitis, sepsis, hemodynamic instability and death.

Imaging XR: pneumatosis intestinalis, air in the portal vein, pneumobilia, perforation. US: Pneumatosis, decreased flow. CT: The test of choice and the gold standard. Can determine etiology and extent of involvement, thus determining course of treatment. Requires a stable patient! MR: No advantage over CT

Mesenteric Ischemia: Diagnosis and Management Begins with history/physical and a high degree of clinical suspicion. Initial treatment is resuscitative and supportive. What does that actually mean? Early surgical consult. May require IR depending on etiology of ischemia.

Cases… A 23 year old female presents with severe, intermittent right lower quadrant pain associated with nausea and vomiting. She has no medical history. Her vital signs reveal tachycardia but are otherwise normal. Physical exam shows a soft abdomen, RLQ TTP without peritoneal signs. Pelvic (which is part of the physical exam), shows scant discharge. If you could only order one test, what would it be? What is on your differential?

Differential Ectopic Pregnancy Ruptured Ovarian Cyst Appendicitis Right-sided diverticulitis TOA Ovarian Torsion Nephrolithiasis Pyelonephritis Endometriosis UTI Heterotopic pregnancy Terminal ileitis

Ovarian Torsion…

Increased ovarian volume (>15cc), multiple follicles and decreased blood flow.

Cases… A 24 y/o male presents with rapid onset, non-radiating, diffuse abdominal pain. He has no medical or surgical history. He is tachycardic and tachypneic. His exam reveals a distended abdomen which is diffusely tender. He has decreased bowel sounds.

Differential? Appendicitis Bowel Obstruction Testicular torsion Perforated Viscus Colitis PUD Peritonitis Mesenteric Ischemia

What happens and what it looks like:

Compared to a Sigmoid Volvulus…

Obstructions: Small and Large Bowel Adhesions Hernias Masses Large Masses Diverticulitis Sigmoid Volvulus

Treatment… NPO NasoGastric Tube suction. Fluid and Electrolyte repletion Antibiotics Surgical consult

Pitfalls: Incomplete exams (rectals, pelvics and genital exams) Incomplete histories Missing abnormal vitals Relying on labs Relying on imaging Not performing serial exams Elderly, the young, the pregnant, altered or psychiatric patients “Constipation” “GERD” “Gastroenteritis” and “UTI”

Other conditions… Systemic DKA Alcoholic ketoacidosis Uremia Sickle cell disease Porphyria SLE Vasculitis Glaucoma Hyperthyroidism Toxic Methanol poisoning Heavy metal toxicity Scorpion bite Black widow spider bite Thoracic Myocardial infarction/ Unstable angina Pneumonia Pulmonary embolism Herniated thoracic disc (neuralgia) Genitourinary Testicular torison Renal colic Infectious Strep pharyngitis (more often in children) Rocky Mountain Spotted Fever Monocucleosis Abdominal wall Muscle spasm Muscle hematoma Herpes zoster

References: Me. SBO PICTURE: http://www.healthhype.com/partial-and-complete-bowel-obstruction-symptoms-and-treatment.html CECAL VOL. http://bestpractice.bmj.com/best-practice/monograph/877/resources/image/bp/2.html Sigmoid: http://www.learningradiology.com/archives2008/COW%20338-Sigmoid%20volvulus/sigmoidvolcorrect.htm Pneumoperitnoeum: http://new.medicalfinals.co.uk/?p=425 Foreign bodies: http://lifeinthefastlane.com/2009/10/top-ten-foreign-bodies/ Gallbladder: http://imaging.consult.com/imageSearch?query=impactions&qyType=AND&global_search=Search&modality=&thes=true&normalVariantImage=false&groupByNode=none&anatomicRegion=&modalityFilter=Ultrasound AAA: http://www.keepingyouwell.com/CareAndServices/VascularLabServices/AbdominalAorticAneurysms.aspx Appendix 1: http://imagingsign.wordpress.com/category/ultrasound/ Appendix 2: http://www.madisonradiologists.com/SvcCTAbdominalPain.htm CT AAA: http://radiographics.rsna.org/content/20/3/725/F44.expansion Cullen’s: http://www.gastrointestinalatlas.com/English/Jejuno_and_Ileum/Etc__Etc_/etc__etc_.html Portal air: http://www.nzma.org.nz/journal/119-1246/2343/ Ovarian torsion: http://medchrome.com/major/gynaeobstr/complications-of-ovarian-cyst/ Ovarian torsion U/S: http://www.med-ed.virginia.edu/courses/rad/edus/index13.html Cecal volvulus diagram: http://imaging.consult.com/image/topic/dx/Gastrointestinal?title=Colonic%20Obstruction&image=fig11&locator=gr11&pii=S1933-0332(06)70677-2 Cecal volvulus drawing: http://www.radiologyassistant.nl/en/4542eeacd78cf Sigmoid volvulus illustration: http://alharthy.com/ Sigmoid X ray; http://rad.usuhs.edu/medpix/topic_display.html?recnum=1608&pt_id=10030&imageid= Small bowel obstruction XR: http://allbleedingstops.blogspot.com/2009/01/solution-to-puzzle.html “other conditions” slide: http://erweb.vghtpe.gov.tw/ skhou/ abdominal%20pain.ppt 91k