Approach to Abdominal Pain Jason Phillilps

The Problem of Pain Approach to Abdominal Pain Jason Phillips, MD ER approach to abdominal pain Chief complaint: abd pain  Labs: CBC, chem, LFTs, lipase  CT abdomen  History  Possible PE How do you approach a workup for abdominal pain What are the most likely possibilities? How do you organize your thoughts? The Problem of Pain  Neurologic basis of pain   Why is it difficult to localize? Why does the intensity of the pain vary?  General overview of approaching a patient with abdominal pain  Pain syndromes Neurologic basis of abdominal pain  Pain receptors respond to   Mechanical stimuli Chemical stimuli  Nociception mechanical receptors are located on serosa, within the mesentery, in the GI tract wall in the   myenteric plexus (Auerbach plexus) submucosal plexus (Meissner plexus) Neurologic basis of abdominal pain  Mucosal receptors respond to chemical stimuli  Substance P, serotonin, histamine, and prostaglandins  Chemical stimuli are released in response to inflammation or ischemia Two basic problems with abdominal pain  Localization of visceral pain  Intensity of pain response Localization of visceral pain  Visceral pain localizes to midline    Bilateral, symmetric innervation Afferent fibers  celiac, superior mesenteric, or inferior mesenteric ganglion Localizes: epigastrium, periumbilical, and lower abdomen Localization of visceral pain  Exceptions to the bilateral rule  Gallbladder  Ascending and descending colon  Although bilaterally innervated, they have predominant ipsilateral innervation Localization of visceral pain  Referred pain    Somatic fiber “cross-talk” Activate same spinothalamic pathways  referred pain as the cutaneous dermatome sharing the same spinal cord level (Gallbladder – scapula) Results in aching pain with skin hyperalgesia and rigidity Intensity of pain response  Threshold for perceiving pain from visceral stimuli has marked individual variability  Balloon distension experiment in IBS History  MOST IMPORTANT CLUE to the source of abdominal pain  Type of pain    Visceral = dull, aching, poorly localized Parietal = sharp, well localized Referred pain History  General location  Generalized, RUQ, epigastric, LUQ, periumbilical, RLQ, LLQ, and „migratory‟ General region localizes organs/structures to include in the DDX Radiation of pain (e.g., acute pancreatitis)   History  Onset of pain   Most gradual, steady crescendo (e.g., cholecystitis) Abrupt, “10/10” – suggestive of perforation  Quality of pain    Colicky (comes and goes) – e.g., gastroenteritis Steady – (e.g., acute pancreatitis; biliary colic is a misnomer) Burning History  Severity of pain   Generally corresponds to severity of illness However, marked patient variability (“12/10 pain” is often functional or has functional overlay) Eating (mesenteric ischemia vs PUD) Position changes (acute pancreatitis, peritonitis)  Aggravating or Relieving factors   History  Associated symptoms    Nausea/vomiting Weight loss Changes in bowel habits Physical exam: Acute abdomen or not?  General appearance and Vital signs  Abdominal exam  Auscultation  Bowel sounds present?  High pitched sounds of obstruction  Stethoscope palpation  Percussion  Tympany = distended bowel  Most humane test for rebound tenderness Physical exam: Acute abdomen or not?  Palpation:    Acute abdomen or not? Peritoneal signs Rebound tenderness Mass? Hernia Leg lift maneuvers (Carnett‟s sign) Abdominal crunch  Abdominal wall maneuvers   Further evaluation  Directed at pain syndromes  Labs  Imaging Is the pain functional or not? Functional abdominal pain  Can be difficult to distinguish from organic pain  Can only be labeled as functional when organic causes are excluded  Can superimpose on organic pain  Should not cause  Weight loss, Anemia, GI bleeding, Fever, Night sweats Is it functional or not?  Clues that are suggestive of functional  Atypical history that lasts 20 sec is not biliary colic  Dyspesia that worsens with a PPI  RUQ  Overly dramatic descriptions of pain  “It feels like a knife stabbing me over and over and then something is pushing inside out” epigastric pain” with a benign abd  Hyperbolic intensity  “11/10 exam Is it functional or not?  Clues that are suggestive of functional  Absence of nocturnal symptoms Exacerbated by stress Distractible exam “Gut feeling”    Pain syndromes Irritable Bowel Syndrome  Prevalence: 10-15% of overall population Only ~15% of patients seek medical care 25-50% of gastroenterology visits Annual healthcare cost: $1.7 billion    Irritable Bowel Syndrome ROME criteria:  12 weeks or more of abdominal pain/discomfort in the last 12 months (does not have to be consecutive)  Two or more features: 1. 2. 3. Relieved with defecation Change in frequency of stool Change in appearance of stool Irritable Bowel Syndrome 3 types of IBS patients  Constipation-predominant   Diarrhea-predominant Alternating Irritable Bowel Syndrome What is the normal range for frequency of bowel movements? Rule of 3s: - Normal = Anywhere from 3x per week to up to 3x per day Irritable Bowel Syndrome Pathophysiology Alterations in motility Visceral hyperalgesia Postinfectious IBS – lymphocytic infiltration of myenteric plexus? Irritable Bowel Syndrome How do you prove its only IBS? Rome criteria positive for IBS   No alarm features and mild symptoms, reassurance and treatment of symptoms  Alarm features or severe symptoms, consider referral to GI Upper abdominal pain  Biliary disease  Dyspepsia  Pancreatitis  Gastroparesis  Other Upper abdominal pain: Biliary disease 1. 2. 3. Most common location – epigastric NOT RUQ Steady onset; last hours (not minutes or seconds) Can radiate to right scapula Biliary colic Cholecystitis Acute cholangitis    Upper abdominal pain: Biliary disease  Workup:   Labs: When are liver tests abnormal? Imaging: What is the most sensitive imaging study for biliary tract disease? What are its limitations?  Upper abdominal pain: Biliary disease  Labs: LFTs increase with choledocholithiasis (first transaminases, then AP/T Bili)  Ultrasound:  Sensitivity 88% 97% Specificity 89% 90% Cholecystitis  HIDA    Gallstones Biliary dilation Choledocholithiasis dilated CBD) 84% 99% 55-91% 50 vs 75% (nondilated vs Upper abdominal pain: Dyspepsia  Dyspepsia = “persistent or recurrent abdominal pain or discomfort in the upper abdomen.”  Vague diagnosis that includes a long DDX Upper abdominal pain: Dyspepsia  80-100% of „dyspepsia‟ is a acid-related phenomenon or functional  Usually an outpatient problem  Peptic ulcer pain = epigastric, burning or hunger-like, worse between meals, relieved with food, nocturnal pain, associated nausea Upper abdominal pain: Dyspepsia  GERD = heartburn (retrosternal burning), water brash (acid taste in mouth), regurgitation, and sensation of dysphagia Upper abdominal pain: Dyspepsia  Functional dyspepsia = same symptoms but no organic etiology can be found   12 weeks over last 12 months Not relieved with BM or associated with alterations in BMs (i.e., NOT IBS) Upper abdominal pain: Dyspepsia  Best test?  3 strategies    Empiric PPI H pylori – test and treat EGD Gastroparesis  Often overlooked as a cause for epigastric pain  Gastroparesis symptoms   Nausea 93% Abdominal pain 90%  Epigastric burning, vague, cramping   Early satiety 86% Vomiting 68% Gastroparesis  60% report pain is worse after eating  80% reports pain interrupted sleep  Vomiting food hours later  Look for important historical clues  Diabetes  Meds (narcotics, anticholinergics)  Recent viral gastroenteritis  CNS disease  Amyloid, scleroderma Gastroparesis  Workup  EGD or UGI – rule out GOO Gastric emptying scan  Upper abdominal pain: Pancreatitis  Acute Pancreatitis = acute epigastric pain that radiates to back, constant, severe, rapid onset within 1 hour, lasts days, associated nausea/vomiting, relieved with sitting forward; assoc restlessness  Rarely diffuse pain, RUQ, or LUQ Upper abdominal pain: Pancreatitis Diagnosis is made when you have at least 2 of the 3 criteria: - Typical pancreatitic pain - Elevation in amylase and lipase - Abnormal imaging Upper abdominal pain: Pancreatitis  Chronic pancreatitis = similar pain, less severe and onset 20-30 minutes after a meal, can be episodic (early in disease course) or constant (late finding)  Associated malabsorption (pancreatic exocrine insufficiency) and diabetes (endocrine insufficiency)  Steatorrhea does not occur until 90% or more of pancreatic function is lost Upper abdominal pain: Other causes  Acute MI  Pneumonia  Splenic abscess or infarct Lower abdominal pain  Appendicitis  Diverticular disease  IBS  Crohn‟s disease  Hernia  Other Lower abdominal pain  Appendicitis = begins as periumbilical pain that localizes to RLQ (McBurney‟s point)   Initially visceral pain (superior mesenteric ganglion) RLQ when inflammation extends to peritoneal surface (parietal pain)  Pain evolves over hours  Exam: peritoneal irritation (rebound) + fever  Labs: Elevated WBC Lower abdominal pain Diverticulitis = usually LLQ abdominal pain    Constant w insidious onset Worsening over days Associated symptoms of fever and worsening constipation Lower abdominal pain  Exam: spectrum of severity   Mild  LLQ tenderness Severe  LLQ rebound  Labs: Elevated WBC  Imaging Lower abdominal pain  70% of diverticulitis in Western countries in left sided. What group of patients usually have right sided diverticultitis (~75%)?  Do seeds cause diverticulitis and should they be avoided? Lower abdominal pain  IBD can give lower abdominal pain with diarrhea, weight loss, hematochezia, fever  These clues are more obvious  However, 10% of patients with Crohn‟s disease will NOT have diarrhea and can present with abdominal pain   RLQ  ileocecal CT, colonoscopy, SBFT Lower abdominal pain  Hernia = weakness or disruption of the abdominal wall      Indirect: at the internal ring Direct: Hesselbach‟s triangle Umbilical Epigastric Incisional Lower abdominal pain  Groin hernias  pain or dull pressure with lifting, straining, or increasing intrabdominal pressure; worse with prolonged standing and at end of day  Physical exam is crucial  Outright pain at rest is concerning for strangulation Lower abdominal pain  If in doubt, consult surgery for an opinion  If a hernia is bright red and impossible to reduce, call a surgeon immediately Lower abdominal pain: Non-GI causes  Nephrolithiasis     Colicky pain (spasms lasting 20-60 mins) Site depends on location of stone (flankgroin) UA: hematuria (neg in 20-30% of cases) CT renal stone protocol Lower abdominal pain: Non-GI causes  Pelvic inflammatory disease     Pelvic pain during menses or coitus Onset during of shortly after menses Bilateral Usually less than 2 weeks Exam critical: speculum and bimanual exam  Diffuse abdominal pain  Gastroenteritis  IBS  Obstruction  Mesenteric ischemia Diffuse abdominal pain  Viral gastroenteritis = colicky abdominal cramps, watery diarrhea, and nausea/vomiting     Incubation 24-48 hours Symptoms begin with abdominal cramps and/or nauseamost have vomiting and watery diarrhea Mild fever, myalgias Lasts 48-72 hrs Diffuse abdominal pain  Obstruction     Periumbilical pain with paroxysms of cramps occurring every 4-5 minutes Abdominal distension Nausea Obstipation may be delayed up to 24 hours History of abdominal surgery or malignancy  Diffuse abdominal pain  Obstruction   Exam: distended appearance, tympanic, high pitched tinkle or large bowel sounds NGT decompression Abdominal x-rays – supine and upright  Ischemia  Acute mesenteric ischemia    Embolism Thrombosis Vasospasm Intestinal angina  Chronic mesenteric ischemia   Can be difficult to diagnose Acute mesenteric ischemia  Embolic  sudden onset of severe, diffuse pain    Writhing in pain Abdominal exam feels benign - :pain out of proportion to exam” Be suspicious in the right patient: atrial fibrillation, mechanical heart valves, age Acute mesenteric ischemia  Thrombotic and non-occlusive  insidious onset of pain  Labs: nonspecific until late in the course  Imaging: mesenteric angiogram Questions?