Acute Abdomen Lecture Notes PDF

ACUTE ABDOMEN Copyright protected lecture material Copies of documents used in this course were made available under Section 107 of the Copyright Act of 1976, the Fair Use Statute. This material has been made available solely for use in this class and the material may not be further di...

ACUTE ABDOMEN Copyright protected lecture material Copies of documents used in this course were made available under Section 107 of the Copyright Act of 1976, the Fair Use Statute. This material has been made available solely for use in this class and the material may not be further distributed to any person outside the class, whether by copying or by transmission in electronic or paper form. If Fair Use does not apply, copyright permission to reproduce these documents has been applied for or granted through the Copyright Clearance Center or the copyright owner. DISCLOSURES We have no financial disclosures. WE ARE NOT RESPONSIBLE FOR ANY INACCURACIES IN THE TRANSCRIPTION OF THE CLOSED CAPTION OF THIS LECTURE.  Understand Understand the pathogenesis of acute abdominal pain. Understand Understand the medical causes of acute abdomen Understand Understand the surgical causes of acute abdomen OBJECTIVES Understand Understand patient. how to take a focused history for an acute abdomen Understand Understand how to perform an abdominal physical exam on a patient with an acute abdomen. Understand Understand and be able to diagnose an acute abdomen ABDOMINAL ANATOMY REVIEW MUSCLES Parietal peritoneum Parietal Lines the abdominal and pelvic cavities. Loosely connected to body wall. Does not include the mesenteries. Is sensitive to pressure, pain, heat, cold, and lacerations. Innervated by somatic afferents. Visceral peritoneum Visceral Covers the abdominal and pelvic viscera. Firmly attached to the underlying tissues. Includes the mesenteries. Is insensitive to touch, cold, heat, and laceration. Has no somatic afferents. Sensory pain fibers carried by thoracic and lumbar splanchnics.  Intraperitoneal RETROPERITONEAL Covered almost ORGANS – SADPUCKER completely with the Suprarenal (adrenal) visceral peritoneum. glands Aorta/IVC Intraperitoneal, Retroperitoneal Duodenum (2nd + 3rd retroperitoneal, Covered on one surface segments) with visceral peritoneum. and secondarily Pancreas (except tail) Secondarily retroperitoneal retroperitoneal Ureters organs Organs that started out Colon (ascending and as intraperitoneal, but descending parts) had a retroperitoneal Kidneys position later in development. Esophagus Rectum - ↑ &  Acute abdomen Any sudden, spontaneous, nontraumatic, severe abdominal pain, typically of less than 24 hours duration. Signs and symptoms of abdominal pain and tenderness often require emergency surgical therapy. Does not always signify the need for surgical intervention, but SURGICAL EVALUATION IS WARRANTED  Triggered by inflammation, Triggered by irritation of Visceral vs ischemia, distention, the parietal peritoneum. traction, and pressure parietal pain Pain is sharp, severe, and Pain is midline, vague, deep, well-localized dull, and poorly localized. Unilateral somatics Bilateral autonomics Local or diffuse peritonitis Intra-abdominal disease not that frequently needs but necessarily surgical surgical intervention  Structures Nervous System Pathways Sensory Level Liver, spleen and central part of Phrenic nerve C3-5 diaphragm Peripheral diaphragm, stomach, Celiac plexus and greater pancreas, gallbladder and small T6-9 splanchnic nerve bowel Mesenteric plexus and lesser Appendix, colon and pelvic viscera T10-11 splanchnic nerve Sigmoid colon, rectum, kidney, Lowest splanchnic nerve T11-L1 ureters and testes Bladder and rectosigmoid Hypogastric plexus S2-4 Anatomic relationships to pain Foregut presents with epigastric pain Stomach Duodenum Liver Pancreas Spleen Biliary tract Midgut presents with periumbilical pain Small bowel to proximal 2/3 of transverse colon Hindgut presents with suprapubic pain. Distal 1/3 of transverse colon to anal verge  Nonsurgical causes Endocrine and Infections and Referred pain Hematologic Toxins and drugs Metabolic Inflammatory Diabetic crisis Sickle cell crisis Narcotic withdrawal Acute rheumatic fever Myocardial infarction Uremia Acute leukemia Lead and other heavy Systemic lupus Pneumonia Addisonian crisis Other dyscrasias metal poisoning erythematosus Pulmonary embolus Acute intermittent Black widow spider Tabes dorsalis Pneumothorax porphyria poisoning Herpes zoster Acute pericarditis Acute Henoch-Schönlein Pleurisy hyperlipoproteinemia purpura Empyema Hereditary Polyarteritis nodosa Hip and back Mediterranean fever Surgical causes Hemorrhage Infection Perforation Ischemia Blockage History of present illness Pain Associated signs and symptoms Most common and predominant Anorexia presenting feature Fever Explore the dimensions of pain Nausea (OPQRST) Vomiting Occurs AFTER pain has started Constipation/obstipation Diarrhea Weight loss Jaundice  Past medical history Could be more helpful than any other single part of the patient’s evaluation. Chronic medical conditions can complicate the patient’s presentation and increase their surgical risk. Past surgical history Laparoscopic vs robotic surgery Medications Can create acute abdominal conditions or mask their symptoms. Narcotics Interfere with bowel activity. Cause obstipation and obstruction Can cause spasm of sphincter of Oddi and exacerbate biliary or pancreatic pain. Suppress pain and can impair the ability to correctly diagnose condition. NSAIDs Increase risk of UGI bleed and perforation Anticoagulants Increase risk of GI bleeds  Other relevant information Ob/Gyn history (for Allergies Family history Travel history Social history women) Last menstrual r/o pregnancy period  General Appearance Vital signs Are they lying in Is the patient the fetal position? febrile? Are they moving Inspection Auscultation Is the patient around? tachycardic? Are they in Hypotensive? distress? Physical Guarding or rigidity Rebound tenderness Exam Percussion Palpation Deep tenderness Bump tenderness Masses External Specialty exams hernias and Pelvic exam Rectal exam or maneuvers male genitalia  Peritonitis Most commonly caused by Severe tenderness to Peritoneal inflammation of a gram-negative infection palpation, +/- rebound any cause. with an enteric organism or tenderness, and guarding. anaerobe. Rebound tenderness – Voluntary guarding – Involuntary guarding– Apply deep gentle pressure Most common cause of Abdominal wall muscle Abdominal wall muscle over the area and then noninfectious inflammation contraction. Muscles will spasm. Muscles remain release rapidly. Increased is pancreatitis relax during inspiration. spastic and tense. pain in the area is felt after release  Physical findings in various causes of acute abdomen. Condition Helpful Signs Perforated viscus Scaphoid, tense abdomen; diminished bowel sounds (late); loss of liver dullness; guarding or rigidity. Peritonitis Motionless; absent bowel sounds (late); cough and rebound tenderness; guarding or rigidity. Inflamed mass or abscess Tender mass (abdominal, rectal, or pelvic); bump tenderness; special signs (Murphy, psoas, or obturator). Intestinal obstruction Distention; visible peristalsis (late); hyperperistalsis (early) or quiet abdomen (late); diffuse pain without rebound tenderness; hernia or rectal mass (some). Paralytic ileus Distention; minimal bowel sounds; no localized tenderness. Ischemic or strangulated bowel Not distended (until late); bowel sounds variable; severe pain but little tenderness; rectal bleeding (some). Bleeding Pallor, shock; distention; pulsatile (aneurysm) or tender (eg, ectopic pregnancy) mass; rectal bleeding (some). Differential diagnosis Most common cause in Varies according to age and younger people is gender appendicitis. Most common causes in Most common surgical older adults diseases result from Biliary disease Infection SBO Obstruction Intestinal ischemia and infarction Ischemia Perforation Laboratory studies CBC with differential Electrolytes, Elevated white count? BUN/Creatinine levels Urine or serum beta- Bandemia? Hemoglobin UA Any electrolyte HCG and hematocrit levels? abnormalities? Platelets? Liver function tests Amylase and lipase Sedimentation rate Lactate levels  Abdominal CXR plain films Imaging US CT  Physical findings Involuntary guarding or rigidity Increasing or severe localized tenderness Tense or progressive distention Indications Tender abdominal or rectal mass with high fever or hypotension for urgent Rectal bleeding with shock or acidosis operation Equivocal abdominal findings along with septicemia Bleeding Suspected ischemia Deterioration on conservative treatment  Radiologic findings Pneumoperitoneum Gross or progressive bowel distention Indications Free extravasation of contrast for urgent Space occupying lesion on scan with fever operation Mesenteric occlusion on angiography Endoscopic findings Perforated or uncontrollable bleeding lesion  Need to evaluate patient to see if they need to go Why surgical Directly to the operating room Be admitted for surgical observation and expected consult is operative intervention necessary Be admitted for surgical observation or further diagnostic work-up Be admitted to the medical service for nonoperative abdominal pain.  Nonspecific Acute Large bowel abdominal appendicitis obstruction pain Most Small Bowel Perforated Diverticulitis common Obstruction peptic ulcer causes of Acute acute Acute Acute mesenteric cholecystitis pancreatitis abdomen ischemia Incarcerated Ureteral or Acute inguinal hernia renal colic salpingitis Stress and ulcers Blood supply Venous drainage  Vagus nerve  Anterior trunk  From left vagus and is on the anterior surface of the esophagus.  Posterior trunk  Larger than the anterior trunk  From the right vagus and is on the posterior surface of the esophagus.   Focal defects in the gastric or duodenal mucosa that extend into the submucosa or deeper. Peptic ulcer  Majority are caused by H. pylori infection and/or disease NSAIDs  Get acid-peptic injury to (PUD) the gastroduodenal mucosal barrier.  Duodenal ulcers have pain after eating.  Gastric ulcers have pain with eating.  Modified Johnson classification for gastric ulcer. I. Lesser curve, incisura. II. Body of stomach, incisura + duodenal ulcer (active or healed). III. Prepyloric. IV. High on lesser curve, near gastroesophageal junction. V. Medication-induced (NSAID/acetylsalicylic acid), anywhere in stomach. Gallstones Gallbladder and extrahepatic biliary system Triangle of Calot Also known as the hepatocystic triangle. Bounded by the cystic duct, common hepatic duct, and liver margin. The cystic artery runs through this triangle.  Triangle of Calot must be cleared of fat and fibrous tissue. Lowest part of the Critical view gallbladder must be separated from the cystic of safety plate, (the liver bed of the gallbladder). Only 2 structures should be seen entering the gallbladder. 55 cholangiogram GALLSTONE PANCREATITIS Small Bowel Obstruction  Small bowel obstruction Most frequently encountered surgical disorder of the small intestine Most common cause in patient with previous surgery is intra-abdominal adhesions. Most common cause in patient without previous surgery is hernia. Presentation Colicky abdominal Hyperactive or pain, nausea, Abdominal hypoactive bowel vomiting, and distention sounds. obstipation. Vomiting more If feculent, it is a common with more established proximal obstruction. obstructions. Partial SBO Only a portion of Continued passage of intestinal lumen is flatus and/or stool occluded, allowing beyond 6 to 12 hours passage of some gas after onset of and fluid. symptoms Strangulation is less Occurs slowly likely to develop. Closed loop Dangerous form in which a segment of intestine is obstructed both proximally and distally Gas and fluid can’t escape a rapid rise in luminal pressure, and a rapid progression to strangulation. Differential Diagnosis Meckel’s Adhesions Hernia Gallstone ileus diverticulum Diverticulitis Foreign body Intussusception Volvulus Tumor Gallstone ileus Erosion of the gallbladder wall into the duodenum, stomach, or colon. This allows gallstones to pass and get trapped in the small intestines or large intestines causing a small bowel obstruction Courtesy of Dr. Frank Gaillard Courtesy of LearningRadiology.com Gallstone ileus Adhesions HERNIAS  Hernia terminology Irreducible Direct Indirect Reducible Strangulated (incarcerated) Are acquired Are Contents of Contents Blood supply due to “congenital” hernia sac can CANNOT be to bowel or developed Failure of the return to the returned to contents of sac weakness in processus abdomen the abdomen is transversalis vaginalis to spontaneously compromised fascia in close. or with resulting in Hesselbach’s manual gangrene triangle. pressure Inguinal Hernia Defects in parietal abdominal wall fascia through which intraabdominal or preperitoneal contents can protrude Accounts for 75% of all abdominal wall hernias Development of a hernia Are lateral to the Are medial to epigastrics the epigastrics Hernias from the posterior view Inflammatory bowel disease Crohn’s Disease Presence of fat wrapping, mesenteric fat creeping onto the serosal surface of the bowel Pathognomonic of Crohn's disease. Can have a “beefy-red” appearance of terminal ileum. Ulcerative colitis Bloody diarrhea Toxic colitis > 6 bloody stools/d, fever, tachycardia, WBC,  Hgb/Hct Can get toxic megacolon All of the above with abdominal pain, tenderness, and distention Appendicitis  Appetite Loss Abdominal pain Classic Order of Symptoms Nausea-vomiting Fever  Pathogenesis Inflammation Local ischemia Perforation Abscess or Peritonitis McBurney’s Point Signs  Perforation Peritonitis Mortality 3% vs. 1% for non-perforated Mortality can be up to 15% in the Complications elderly of Acute Delay of diagnosis Appendicitis Abscess or Phlegmon Sepsis UNCOMPLICATED APPENDICITIS PERFORATED APPENDICITIS Check the If adenocarcinoma is found, need to have right pathology hemicolectomy If carcinoid is found and report is >2 cm and involves base, then need to have right hemicolectomy.  Inflammation and Occurs in 10 to 25% infection associated of people with with diverticula diverticulosis. DIVERTICULITIS Most commonly presents with left- sided abdominal Most common pain, with or cause of fistulas in without fever, and GI tract. leukocytosis. A mass may be present.  Clinical Findings LLQ pain Obstipation Diagnosis: Fever Diverticulitis Leukocytosis Imaging CT with Contrast best avoid barium studies due to frequency of perforation Hinchey classification of Diverticulitis   Antibiotics First Line Therapy for uncomplicated Diverticulitis: ▪ Metronidazole + Ciprofloxacin OR amoxicillin/clavulanate Management To cover anaerobic and aerobic GNR 7-10 days of Rx of ▪ Bowel Rest ▪ Effective in approximately 70% of cases Diverticulitis ▪ FU Colonoscopy 6-8 weeks after recovery r/o Neoplasms or strictures ▪ Prevention: Avoid Nuts, Popcorn??? High Fiber Diet or High Fiber supplements  Immediately Perforation with Peritonitis Decompensated Clinical Status When to Failure to respond to Medical Management after 72 hrs. call surgery? Delayed Second episode Most definitive treatment option is SURGERY  Intestinal obstruction distal to ICV. Most common cause of LBO is cancer Volvulus Large bowel Diverticulitis obstruction Crohn’s Hernias Intussusception Foreign body Fecal impaction Cecal Volvulus Courtesy of Dr. Jeffrey Parks Sigmoid Volvulus  Cecal Sigmoid Resect Endoscopic Right detorsion Treatment hemicolectomy with primary ileocolic anastamosis Colon cancer Colon resections A – Right colectomy B – Extended right colectomy C – Transverse colectomy D – Left hemicolectomy E – Extended left hemicolectomy F – Sigmoid colectomy Ischemic colitis Sudden decrease in blood flow resulting in a low-flow state. Most commonly affects the watershed areas with a limited collateral blood supply, such as the splenic flexure and left colon. 85% will resolve spontaneously within 2 weeks. Seen in patients with history of aortoiliac surgery (AAA), MI, cardiopulmonary bypass, hemodialysis, and medications.  Presentation Physical examination reveals Mild to moderate rectal mild to moderate abdominal Acute onset of LLQ pain bleeding or bloody diarrhea tenderness over the followed by within the first 24 hours. affected bowel, most often left-sided. Bleeding is not massive and rarely requires transfusion  moderate to severe pain Hypoperfusion increased stools with blood Ischemic Paralytic phase Pain less severe colitis abdomen distended Mucosa gangrenous Shock Metabolic acidosis Diagnostic tests Flexible sigmoidoscopy or colonoscopy Plain films of the Colonoscopy with biopsies abdomen makes the definitive diagnosis CT scan Barium enema Treatment NONSURGICAL SURGICAL Bowel rest. Peritoneal signs suggesting Serial abdominal perforation examinations and monitored for Gangrenous colitis bleeding, fever, Massive bleeding, leukocytosis, and Toxic megacolon electrolyte Recurrent sepsis abnormalities. Ex lap with bowel Broad-spectrum resection if failed intravenous antibiotics medical management Acute mesenteric ischemia (AMI) One of the most catastrophic vascular disorders medical and surgical emergency 1/1000 hospital admissions 80% mortality Early recognition and prompt treatment necessary to prevent irreversible ischemia and necrotic bowel. PAIN OUT OF PROPORTION TO EXAM Etiology and pathogenesis Reduction in Most commonly intestinal blood due to flow Non- Arterial Venous occlusive Hypercoagulable, oral Sepsis, hypovolemia, Embolic Thrombotic contraceptives, liver systemic vasoconstriction cirrhosis Cardiac A fib, CHF, Atherosclerosis cardiomyopathy Work up Gold standard is mesenteric arteriography Shows occlusion or near- occlusion of the CA and SMA at or near their origins from the aorta.  AMI embolism Sudden severe abdominal pain PAIN OUT OF PROPORTION TO EXAM Vomiting H/O atrial fibrillation, recent MI Embolism has blocked the main artery or branches of the SMA  AMI thrombosis Sudden severe abdominal pain which can be progressive Vomiting, diarrhea, and/or melena H/O diffuse atherosclerotic disease. Postprandial pain and weight loss Thrombosis of celiac trunk, SMA or IMA origin  Treatment AMI embolism or thrombosis Revascularize mesenteric circulation and prevent the development of bowel infarction. Mesenteric artery bypass or endarterectomy.  Mesenteric Venous Thrombosis Nonspecific GI symptoms, abdominal distension, worsening of general condition H/O portal hypertension, VTE, oral contraceptives, estrogen use, thrombophilia pancreatitis. Thrombosis of SMV with progression to portal vein. Treatment Mesenteric Venous Thrombosis Systemic anticoagulation  Nonocclusive Mesenteric Ischemia Progressive mild abdominal pain H/O cardiac failure, low flow states, vasopressors, multiorgan failure, abdominal compartment syndrome. Stenosis of the SMA.  Treatment Nonocclusive Mesenteric Ischemia Nonoperative management with bowel rest, antibiotics, and volume expansion  Chronic Mesenteric Ischemia Develops slowly Lack of blood supply From atherosclerotic allowing for the in splanchnic region. lesions development of collaterals. cachectic with strong At least 2 of the Rarely causes smoking history with arteries are occluded intestinal infarction. abdominal pain and or stenosed. weight loss  Chronic Mesenteric Ischemia Postprandial abdominal pain "food-fear” weight loss. These patients are often thought to have a malignancy and are misdiagnosed. Treatment Chronic Mesenteric Ischemia Revascularization CASE #1 A 45-year-old man presents to the ER with a 6-hour history of acute abdominal pain. He states the pain started in the epigastric area and has become more severe in the last 2 hours. On PE, the patient is tachycardic, hypotensive, and febrile. On abdominal exam, he has marked tenderness to palpation, involuntary guarding, and rebound tenderness. What is your differential diagnosis? What is your plan? Case #2 A 23-year-old woman presents to the ER with a 8 hour history of abdominal pain, nausea, and vomiting. She states her pain is located in the RUQ and is getting worse. This is her 3rd episode in 4 months. PE is significant for tenderness to palpation in the RUQ. There is no guarding or rebound. There is inspiratory respiratory arrest on deep palpation in the RUQ. What is your differential diagnosis? What is your plan? Case #3 A 96-year-old woman presents to the ER with a 10 hour history of nausea, vomiting, and abdominal pain. PMH is significant for atrial fibrillation. She states her pain is 10/10 but her PE is remarkable for a soft abdomen. There is no guarding, no rebound, and no percussion tenderness. Her physical exam findings do not correlate with her reported pain level. What is your differential diagnosis? What is your plan? Case #4 A 68-year-old man presents to the ER with a 7 hour history of abdominal pain, nausea, and vomiting. PE is remarkable for a soft, mildly distended abdomen with tenderness to palpation in the LLQ. There is guarding, rebound, and percussion tenderness. What is your differential diagnosis? What is your plan? Case #5 A 28-year-old woman presents to the ER with a 6-hour history of abdominal pain, nausea, and vomiting. She states she felt nauseous, followed by abdominal pain. She has only starting vomiting 2 hours ago. PE is remarkable for tenderness to palpation in the RLQ. There is no guarding, rebound, or percussion tenderness. What is your differential diagnosis? What is your plan? Case #6 A 26-year-old man presents to the ER with a 6 hour history of abdominal pain, nausea, and vomiting. PMH is significant for sickle cell disease. PE is remarkable for tenderness to palpation in the LUQ. There is no guarding, rebound, or percussion tenderness. What is your differential diagnosis? What is your plan? Additional references and images courtesy of Schwartz Principles of Surgery Current Diagnosis and Treatment Surgery Radiopedia.org Johns Hopkins Medicine Division of Gastroenterology and Hepatology