Abdominal pain

BY PROF/ GOUDA ELLABBAN

Objectives• Understand Anatomy and Physiology of

Abdominal Pain• Establish a Diagnosis Based on History

and Physical• Know Appendicitis• Pearls in Diagnosis• Convince you to read a small paperback

if you’ve not done so already

Must Read for any Doc

Cope’s Principles

1. It is necessary to make a serious attempt at diagnosis, predominantly by means of history and physical exam

2. It is only by a thorough history and physical that one can make a diagnosis

3. Diagnose Early

Cope’s Principles4. The majority of severe abdominal pains

that ensue in patients who have been previously fairly well, and that lasts as long as six hours, are caused by conditions of surgical importance

5. Apply the knowledge of anatomy6. Apply the knowledge of physiology7. Understand visceral and somatic pain

Appendicitis

• “To know acute appendicitis is to know well the diagnosis of acute abdominal pain”

--Sir Zachary Cope

Left beanRight bean

Anatomic Basis of Pain• Sensory Neuroreceptors in Abdomen located in:

– Mucosa and muscularis propria of hollow viscera

– Serosal structures like peritoneum– Mesentery

• Sensory neuroreceptors involved in regulation of secretion, motility, and blood flow

Stimulants of Pain• Abdominal visceral nociceptors respond to mechanical

and chemical stimuli• Stretch is principle mechanism of pain• Cutting, tearing, crushing of viscera does not result in

severe pain• Mechanoreceptors triggered after:

– Rapid distension of hollow viscous-intest obstr– Forceful muscular contraction- biliary/renal colic– Stretching of an organ or capsule- liver/kidney

congestion• Ischemia can trigger visceral pain

Types of Pain• Visceral

– Visceral nociceptors triggered…stretch/contraction– Dull poorly localized usually in midline epigastrium,

periumbilical, or lower mid abdomen– Cramping, bloating, gnawing

• Somatoparietal– Noxious stimuli to parietal peritoneum– Intense well localized- i.e. McBurney’s

• Referred– Pain felt in areas remote from disease origin- i.e

biliary colic as scapular pain

Visceral Pain Sites

The Painful Abdomen• Pain vs Tenderness

– Distinction is critical to making the diagnosis

– Be precise: • Conceptually • Verbally • Written Documentation

Pain- is a subjective symptomTenderness is an objective sign

Pain vs Tenderness• Based on abdominal

innervation:– Visceral Pain

• Sense stretching and ischemia only

• mediated via Visceral Afferent fibers

– Follow the blood supply

– Diffuse, not mapped 1:1 on sensory cortex

Multiple Dermatome Diagnosis

• Poorly localizing visceral innervation makes these diseases present in vague, confusing manner– Pneumonia– Acute MI– GERD– Biliary Colic– PUD– Pancreatitis– Hepatitis

Pain and Tenderness(continued)

• Tenderness– Somatic Afferent

Innervation• Parietal peritoneum• Abdominal Wall

– Precisely mapped on sensory cortex

Obtaining History - Chronology

• Sudden well localized = possible intraabdominal catastrophe – perforated viscous– Mesenteric infarct– Ruptured aneurysm

• Progression– Appendicitis increases– Gastroenteritis decrease– Colic crescendo/decrescendo

• Hours to days more concerning than weeks

Obtaining History - Location

• May not be specific• May refer • Change in location may be a marker of

progression- visceral parietal irritation– Appendicitis McBurney’s Point– Perforated ulcer vague pain to

peritonitis

Obtaining History – Aggravating and Alleviating Factors

• Peritonitis lie motionless• Renal colic writhe, unable to get comfy• Fatty foods biliary colic• Improves with eating DU• Worse with eating GU, mesenteric

ischemia• Intensity is based on the frame of reference

of the patient. Be careful to suggest a scale

Obtaining History

• PMH….yes and critical– Bowel obstruction, renal colic, PID tend to

recur

• ROS– Fever, chills infectious– N/V and no flatus bowel obstruction– Dysuria, pregnancy, menstrual history

Physical Exam

• Still patient peritonitis• Writhing patient colic, bowel

obstruction• Old, young, diabetic,

immunocompromised, alcoholic may present with minimal symptoms

Physical Exam• Severe tenderness with rigidity = peritonitis• Mild tenderness more likely gastroenteritis• Palpate areas of least pain to most pain• Peritonitis – shake bed gently, deep breath• Pelvic and rectal on patients with severe

abdominal pain

Physical Exam• Prepare the patient

• warn them• make them comfortable• take tension off the abdominal wall• Pillow or bend the knees• Expose the entire abdomen- Xiphoid to

pubis• Distract with conversation• Watch their eyes• Palpate with the stethoscope

Guarding – voluntary contraction of the abdominal wall musculature.

Rigidity – involuntary control of the abdominal wall musculature.

Rebound tenderness– the clinician maintains hand pressure over an area of tenderness. The clinician then releases the hand pressure suddenly. Pain denotes a positive test. Cope’s does not recommend this exam due to the discomfort to the patient who already has localized guarding.

Cope’s Early Diagnosis of the Acute Abdomen

Peritonitis- The Exam

Cough test – if a patient has peritonitis, any movement of the abdomen will elicit pain. Therefore a cough in a patient with peritonitis will precipitate pain (positive test).

Abdominal wall tenderness test (Carnett’s sign) – helps to distinguish between lesions of the abdominal wall which cause pain and peritonitis. The examiner identifies the area of tenderness and applies moderate pressure. The patient is asked to lift their head and shoulders. If the pain is increased, the test is positive (patient has a lesion of the abdominal wall not peritonitis). Patients with peritonitis should have decreased pain due to the tense abdominal wall.

Cope’s Early Diagnosis of the Acute Abdomen

Peritonitis- The Exam

PSOAS SIGN

Principle - stretch of pelvic musculature (iliopsoas muscle) will elicit pain.

Roll the patient on their left side and hyperextend the right hip.

Pain with extension is a positive signCOPE’S EARLY DIAGNOSIS OF THE ACUTE ABDOMEN

OBTURATOR SIGN

Principle – same as psoas sign.

The examiner flexes the patient’s right hip and internally rotates the right hip

Pain with internal rotation is a positive sign.

COPE’S EARLY DIAGNOSIS OF THE ACUTE ABDOMEN

Rovsing’s sign – also know as indirect tenderness. The sign is positive when pressure applied to the left lower quadrant results in right lower quadrant pain.

Psoas/ Obturator sign – see previous slides.

Rectal tenderness – patients with appendicitis involving the pelvis may have rectal tenderness on examination.

COPE’S EARLY DIAGNOSIS OF THE ACUTE ABDOMEN

Appendicitis Signs

Mc burney’s point tenderness – a point 1½ -2 inches from the anterior superior spinous process of the ileum on a straight line drawn from that process to the umbilicus. In 1889 Charles Mcburney stated that all patients with appendicitis had maximal pain at this point.

Malignancy

Courvoisier’s sign – a palpable nontender gall bladder in a patient with jaundice suggesting extrahepatic obstruction of the biliary system secondary to malignancy (original description).

Cholecystitis

Murphy’s sign – with the examiner’s fingers positioned along the inferior border of the liver in the right costal arch the patient is allowed to inspire. During inspiration the inflamed gallbladder touches the examiners fingers resulting in the sudden cessation of inspiration.

Boas’ sign – hyperesthesia and referred pain to the right costophrenic angle in patient’s with acute cholecystitis.

Abdominal Aortic Aneurysm - The Exam

The patient’s abdomen should be relaxed with the knees flexed.

The examiner feels cephalad of the umbilicus for the aortic pulsation.

Place both hands on the abdomen with the index finger on either side of the pulsating aorta. Estimate the width ( nl <2.5cm in width).

JAMA 1999;281:77-81

BATES 8TH ED, 2003

Laboratory and Radiology Studies

• “Even today, it remains true that the vast majority of diagnosis... are still made on the basis of a careful history and physical examination.”

-William Silen

Lab Evaluation

• CBC, UA, lytes • Pregnancy test for all women of reproductive

age with lower abdominal pain• LFT, amylase, lipase on all with upper

abdominal pain• Anything else of little yield unless specifically

indicated

Radiographic Evaluation

• Plain radiograph– Upright and supine abdomen and chest xray

• Ultrasound superior for biliary and pelvic symptoms• CT Abdomen and Pelvis

– Evaluates vasculature, inflammation, solid organs– Stone protocol best to rule +/- renal stone– Although adds to accuracy of appendicitis, may

delay diagnosis

Helpful Hints on Lab/ X-ray

• Perform the H & P first• X-rays/labs not always needed• X-rays/labs can be misleading• If looking for free air keep patient upright or in

lateral decubitus position for 5-10 minutes• Pleural effusions very common in

subdiaphragmatic inflammatory process so think twice before inserting large needle

Diagnosis?

Withhold Pain Meds and Wait for the Surgeon-- NO! read fine print later

• "The patient cries out for relief, the relatives are insistent that something be done, and the human discipline of Aesculapius is driven to diminish or banish the too-obvious agony by administering a narcotic. The erroneous notion that narcotics can obscure the clinical picture has falsely promoted the unfortunate dictum that these analgesics should be withheld until a diagnosis is firmly established. With the multiple layers of health care personnel that a patient must navigate, i.e., triage nurses, medical students, residents, and attending physicians, combined with new, innovative, yet prolonged tests, the suffering patient is sometimes forced to wait many hours until pain relief is offered”

• "this cruel practice is to be condemned, but I suspect that it will take many generations to eliminate it because the rule has become so firmly engrained in the minds of physicians."

Cope’s 20th editionBr J Surg. 2003 Jan;90(1):5-9. Review J Am Coll Surg. 2003 Jan;196(1):18-31.

Case

A 37-year-old woman with no PMH went to clinic complaining of vomiting and periumbilical abdominal pain for 6 hours. On physical examination, she was afebrile, BP 110/70, HR 85. Abdomen was soft, with no rebound or guarding. She was diagnosed with gastroenteritis, discharged with antiemetics, and told to return for persistent vomiting, pain, or new fever.

MMWR Online Case June 2003

Case (cont.)Patient went to PCP’s office 2 days later with persistent abdominal pain; vomiting had resolved. On physical exam, patient was afebrile, with normal vital signs. Abdomen was diffusely tender, with localization around the umbilicus. Pelvic exam revealed no cervical motion and mild adnexal tenderness. Diagnosis: mittelschmerz vs. ovarian cyst. Transvaginal ultrasound ordered for following week. Patient told to take naproxen for pain.

Case (cont.)

The next day, the patient returned to the ED with persistent and severe pain. The ED attending performed a pelvic exam and ordered a CT scan of the abdomen and pelvis. CT revealed a perforated appendix.

Perforated Appendix

Case (cont.)

The patient was seen by general surgery and it was decided not to take her to the operating room immediately due to the peritonitis. She was admitted and started on IV antibiotics. Her hospital stay was prolonged due to ileus. On hospital day number #8, her WBC count began to rise. A repeat CT scan was obtained.

Intra-abdominal Abscess

Case (cont.)

CT revealed an intra-abdominal abscess “the size of an orange.” The patient underwent percutaneous drainage by interventional radiology. On hospital day #13, she was discharged home with a plan to follow-up for elective appendectomy.

Case (cont.)

Shortly after discharge, the abdominal pain returned. The patient returned to the ED and underwent a repeat CT scan, which revealed a small bowel obstruction. The patient went to the operating room the next day for lysis of adhesions and appendectomy. Eight days later, the patient was discharged home. She has returned to her previous state of health.

Complications of Perforated Appendix

• Wound infection and dehiscence• Intra-abdominal abscess• Sepsis• Prolonged ileus• Pneumonia• Bowel obstruction• Infertility

Graff L, et al. Acad Emerg Med 2000;7:1244-55. Mueller BA, et al. NEJM 1986;315:1506-8.

Appendicitis Order of Symptoms and Signs

• The usual progression1. Pain (usually epigastric or umbilical)2. Anorexia, nausea, vomiting3. Local tenderness- abdominal or pelvic4. Fever5. Leukocytosis

– Goal to diagnose before peritonitis sets in

Challenge of Diagnosing Appendicitis• Diagnosis uncommon; clinicians accustomed

to ruling out rather than ruling in disease• High incidence of missed diagnoses due to

low suspicion – 20%-40% misdiagnoses in some populations

• Implementation of diagnostic algorithm may combat this effect – Reduce misdiagnosis rates to 6%

Naoum JJ, et al. Am J Surg 2002;184:587-9.

Challenge of Diagnosing Appendicitis

• Classic signs of appendicitis increase likelihood of disease

– Epigastric pain, radiating to RLQ, rebound, fever

• Classic presentation not typical

– WBC count normal in 10%-30%

– Early disease often presents with normal vitals, physical examination

Wagner JM, et al. JAMA 1996;276:1589-94.

Abdominal CT in Appendicitis

• CT can enhance diagnostic accuracy– Sensitivity 80%-100%

• CT can delay diagnosis– Reserve for men with atypical presentation

and for women in whom pelvic pathology may mimic appendicitis

• CT in low-risk population will lead to increase in false positive readings– Potential increase in unnecessary surgery

Ege G. et al. Br J Radiol 2002;75:721-5. Maluccio MA. et al. Surg Infect 2001;2:205-11.

Abdominal Pain in the Clinic/ED

• Maintain suspicion for early disease• Consider CT in appropriate population• Consider inpatient observation• Always provide detailed follow-up and

discharge instructions– Include warning signs and symptoms to

prompt return visit to Clinic/ED

Take-Home Points• Appendicitis is an uncommon but

important cause of abdominal pain • Presentation is often atypical• Complications of missed or delayed

diagnosis are multiple and morbid• To decrease missed appendicitis,

consider CT scan, inpatient observation, and/or detailed follow-up instructions

• Use CT scan with caution

Take-Home Points (cont.)

• Avoid “anchoring”– Always question conclusions of previous

providers, particularly as new information accrues

• Consider implementing diagnostic algorithms to ensure that appendicitis is in the differential, even in atypical cases

• “Close the loop” by obtaining follow-up on clinical outcomes

Differentiation From Gastroenteritis• Features of AGE

– flu like symptoms– vomiting likely before pain – often profound diarrhea– tenderness and rigidity absent or minimal

• Do not be comfortable with diagnosis of AGE

Challenges to Patient Safety

• Excessive cognitive burden• Time pressure• Multiple interruptions• No pre-existing relationship with

patients

Summary• Obtain a detailed history• Do a careful and thoughtful exam• Appropriate labs and x-ray with differential in

mind• Frequent re-evaluation for progression• Pain meds as indicated• Read Cope’s and know appendicitis• Know when to call your surgeon

Questions,Comments,Thoughts?