Why EBM

1
Why EBM?

• Two polar views on physical exam findings
• Some clinicians believe that all traditional
  physical signs remain accurate today.
• Others believe that physical diagnosis has little
  to offer the modern clinician and that
  traditional signs, although interesting, cannot
  compete with the accuracy of modern technology.
• EBM serves to bridge the gap it can pinpoint
  tests that are outdated and best discarded,
  versus findings that are highly accurate and
  probably underused.
• EBM is not cookbook medicine but allows us to
  recognize the strengths and limitations of what
  we do.
• EBM allows us to hone our bedside diagnostic
  skills to better serve our patients and direct
  further workup.

2
Objectives

• By the end of these two didactic sessions,
  participants will be able to
• --describe the components of the complete
  abdominal exam inspection, auscultation,
  percussion, palpation
• --describe specialized maneuvers for detecting
  certain disease states
• --recognize strengths and limitations
  (sensitivity and specificity, likelihood ratios)
  of specialized physical exam maneuvers and
  positive findings

3
Timeline

• Discussion of PE findings and their reliability
  during the routine abdominal exam (inspection,
  auscultation, palpation, percussion) 45 minutes
• 15 min break
• Discussion of Cirrhosis, AAA and Appendicitis
  45 minutes

4
Terminology

• Sensitivity of a test proportion of patients
  with the disease who have the sign (positivity in
  disease PID).
• Specificity of a test proportion of patients
  without the disease who have a negative test
  (negative in heath NIH).
• When present, physical signs with a high
  specificity greatly increase the probability of
  disease. SPIN a specific test, when positive,
  rules in condition.
• When absent, physical signs with a high
  sensitivity greatly decrease the probability of
  disease. SNOUT a sensitive test when negative
  rules out condition.
• In general, tests or signs used as screening
  should have a high sensitivity, whereas tests or
  signs used to confirm a diagnosis should have a
  high specificity.

5

• Positive likelihood ratio the proportion of
  patients with the disease who have a particular
  finding divided by the patients without the
  disease who also have the same finding.
• LR (sens)
• (1- spec)
• Negative likelihood ratio the proportion of
  patients with the disease lacking a specific sign
  divided by the proportion of patients without the
  disease also lacking the sign.
• - LR (1-sens)
• (spec)
• The closer a (-)LR is to zero, the more
  convincing the finding is at arguing against
  disease.
• A () LR greater than one increases the
  probability of disease.

6
EBM and the Abdominal ExamInspection

• Ecchymoses. Described in a wide variety of
  conditions pancreatitis, ectopic pregnancy,
  ischemic bowel, splenic rupture, intrahepatic
  hemorrhage from tumor, perforation of duodenal
  ulcer, ruptured AAA, post liver biopsy.
• Blood travels along falciform ligament to the
  periumbilical area, or along fascial planes
  behind the kidney to the lateral border of the
  quadratus lumborus muscle.
• Sensitivity and specificity are low both around
  3.
• Why look for it? Fast, simple, part of the
  routine exam.

7
Inspection

• Striae red or purple striae are found in about
  56 of patients with confirmed Cushings disease.
• Sens 46-52 Spec 63-78
• LR 1.9 (to compare moon facies 1.6, HTN 2.3,
  central obesity 3.0, ecchymoses 4.5)

8
Auscultation Bowel sounds

• For detecting bowel obstruction large series
  of patients show that 40 have hyperactive bowel
  sounds, 25 have diminished or absent bowel
  sounds (time course)
• Hyperactive BS sens 40-42, spec 89-95. LR if
  present 5.0 negative LR 0.6.
• Abnormal bowel sounds sens 63-93, spec
  43-88. () LR 3.2, (-) LR 0.4.

9
Bowel sounds, Plain English

• If a patient has normal bowel sounds,
  obstruction less likely.
• If a patient has hyperactive bowel sounds, this
  finding is more specific for SBO but is present
  less frequently.
• Any abnormality of sound is more sensitive, but
  less specific for SBO (youll hear it more often
  but it might not mean as much.)

10
Auscultation Bruits

• Bruits occur in 4-20 of healthy normals.
  Usually systolic, usually located between xyphoid
  and umbilicus.
• Sources include AVMs of gut, kidney celiac
  artery.
• These rarely radiate beyond 4 cm. Would
  generally not be present posteriorly (Sub-CVA,
  flanks)
• In pts with renal artery stenosis, a systolic
  bruit may be heard in the same spot but can
  radiate to one side. (Sens 27-28, Spec 89-96,
  LR 4.8)
• Requiring a diastolic component makes this test
  much more specific. (Sens 39, Spec 99, LR
  38.9)

11
Percussion/Palpation Liver

• Liver span an index of liver size, not a
  precise measurement.
• Usually underestimates actual value (0.6 to 0.7)
  when compared to ultrasound or uptake scans.
• Very depended on examiner technique. Experienced
  clinicians in one study differed on average by 8
  cm!
• Detecting enlarged liver by span Sens 50-71,
  Spec 56-77, LR 1.7.
• What about palpation (feeling liver edge below
  costal margin)? Highly specific (meaning that
  what is felt is actually the liver.)
• However, the palpable liver edge poorly
  correlates with true hepatomegaly (LR 1.7)

12
Auscultation of the Liver

• Scratch test three conflicting studies. One
  reported that 78 of estimated measurements where
  within 2 cm of actual border.
• This is compared with 44 for conventional
  percussion and palpation.
• Second study favored palpation.
• Third study showed no correlation between
  scratching out liver and U/S in 11 examiners.
• Current recommendations needs more evaluation.

13
Splenomegaly

• An important physical exam sign as it can be
  associated with potentially serious conditions.
• Sought not infrequently in clinical settings
  (anemia mono).
• It is useful to look for other PE signs while
  assessing splenomegaly (pallor, jaundice,
  hepatomegaly, LN enlargement).
• Very massive spleens have a specific differential
  Dx.

14
Splenomegaly Diff Dx

• With intense jaundice hepatic disease and
  portal HTN
• With mild jaundice hemolytic anemia
• With pallor leukemia, lymphoma, hypersplenism
  from any cause
• With LN leukemia, lymphoma, sarcoid
• With hepatomegaly portal HTN, leukemia, PCV,
  hemolytic anemia, myeloid metaplasia, Gauchers
• With massive spleen chronic granulocytic
  leukemia, myeloid metaplasia, PCV, Hodgkins,
  Malaria, Kala-Azar, Gauchers
• With submassive spleen infectious, pernicious
  anemia, hemolytic anemia, sarcoid, acute
  leukemia, portal HTN, CLL, lymphomas other than
  Hodgkins

15
Percussion of the Spleen

• Spleen percussion sign (Castell) lowest left
  intercostal space in the anterior axillary line
  is percussed on inspiration and if dull,
  positive.
• Nixons right lateral decub, spleen percussed
  from pulmonary resonance obliquely to lower
  costal margin if dullness greater than 8 cm,
  positive.
• Traube triangular space over left lower
  anterior part of chest. Dullness suggests
  pleural effusion vs. splenomegaly.
• Sensitivity is low for all, specificity slightly
  higher.
• LR for Castell and Traube around 2.0 Nixons
  nonsignificant.

16
Palpation of the Spleen

• So many techniques, so little time
• One study comparing the most common methods found
  all to be equivalent (palpation from pts right,
  hooking method, pts fist under left CVA, right
  lat decub).
• The finding of a palpable spleen not found very
  often (insensitive) but if found, argues strongly
  for splenomegaly (highly specific LR 9.6).

17
Palpation Peritonitis

• Rigidity involuntary contraction of the
  abdominal musculature in response to peritoneal
  inflammation.
• Rebound tenderness withdraw examining hand
  abruptly, can elicit pain in the immediate area
  vs. elsewhere.
• Cough test is positive if the patient shows signs
  of pain (grimacing, flinching) after coughing.
• Abdominal wall tenderness test (or sit-up
  maneuver) is NEGATIVE in acute peritonitis.

18
Palpation Cholecystitis

• Murphys Sign.
• Back tenderness.
• Sonographic Murphys Sign finding of maximal
  tenderness over the gallbladder during the
  ultrasound procedure.
• Sens 63, Spec 94, positive LR 9.9 and negative
  LR 0.4.

19
Palpation Renal colic

• Flank tenderness sens 15, spec 99 with a LR
  of 27.7, -LR of 0.9.
• Renal tenderness sens 85 spec 76, LR 3.6,
  -LR 0.2.
• Compare that to microscopic hematuria sens 75,
  spec 99, LR of 73.1 and LR of 0.3.

20
Cirrhosis/Ascites

• Elevated hydrostatic pressure
• --Cirrhosis
• --CHF or right sided heart failure
• --Constrictive pericarditis
• --IVC obstruction
• --Hepatic vein obstruction (Budd Chiari)
• Decreased osmotic pressure
• --Nephrotic syndrome
• --protein-losing enteropathy
• --malnutrition
• --cirrhosis

21
Cirrhosis/Ascites

• Excess fluid production
• --Infections (peritonitis) TB, bacterial,
  parasitic
• --Carcinomatosis with peritoneal seeding
• --Benign ovarian tumors (Meigs Syndrome)
• --Pancreatic ascites (leaking pseudocyst)
• --Eosinophilic gastroenteritis
• Lymphatic obstruction
• --Tumor
• --Trauma
• --congenital anomaly
• --infectious (filariasis, TB)

22
Cirrhosis/Ascites

• Inspection generalized abdominal distention.
• Experiments with cadavers and then healthy
  volunteers reveal 500cc-1100cc of peritoneal
  fluid necessary before physical signs occur.
• In patients lying supine, peritoneal fluid tends
  to gravitate toward the flanks.
• Air filled intestines float up to the abdominal
  surface, like buoys in the ocean, and tend to
  cluster in the periumbilical area.

23
PE maneuvers to detect Ascites

• Bulging flanks, everted umbilicus.
• Flank dullness a horizontal border between
  dullness in the flank area and resonance or
  tympany in the periumbilical area.
• Shifting dullness the above horizontal line
  changes with patient position. It should shift
  away from the side that is dependent.
• Fluid wave clinician places one hand against
  lateral wall of abdomen, and uses the other to
  tap firmly on the opposite wall.
• The fluid wave will be transmitted to the other
  hand, eliciting a positive response.
• Applying pressure along the midline anterior
  abdominal wall (pt.s hand, assistants hand)
  prevents false positive due to subcutaneous
  tissue.

24
Abdominal Aortic Aneurysm (AAA)

• Fairly common present in 1-2 of the older
  population 10,000 deaths per year in the US
• Risk factors age, male sex, smoking history
• Natural history is to slowly enlarge over a
  period of years to decades
• Rupture is catastrophic mortality 80
• 31 of cases originally detected by routine
  examination

25
AAA

• The physical sign of note is a pulsatile mass.
  Abdominal bruits, absent or dimished pulses have
  no predictive value.
• Perform palpation with the patient supine and
  knees raised, soles of feet on the table.
• Feel first for the aortic pulsation, just above
  umbilicus.
• Position both hands on the abdomen, palms down,
  with the index finger on either side of
  pulsation. Include some laxity of abdominal skin
  in between two fingers.
• Confirm pulsation (each systole should move
  fingers apart expasile).

26
AAA

• Normal aortic width 2.5 cm or less.
• Sensitivity of palpating an asymptomatic AAA
  increases as the diameter of the aneurysm
  increases.
• 29 3.0-3.9 cm
• 50 4.0-4.9
• 76 5.0 cm or greater
• Sensitivity diminishes greatly with obesity,
  esp abdominal girth gt 100 cm (measured at the
  umbilicus.)
• Sensitivity of palpation of a ruptured AAA
  ranges from 45-97.
• If you suspect ruptured AAA, must image!

27
AAA Ruling out

• A negative examination in a thin person argues
  strongly against an aneurysm greater than 5 cm.
• Can follow with serial exams, or,
• If clinical suspicion is high (multiple risk
  factors history of vascular disease elsewhere)
  order ultrasound.

28
Appendicitis

• Relatively common cause of abdominal pain
  lifetime risk 7.
• In the ED, 25 of pts younger than 60 evaluated
  for abdominal pain will have appy.
• Age gt60, 4.
• Children ambulatory setting 2.3, admitted
  32.

29
Appendicitis

• Classical history begins with pain, usually
  periumbilical or located in the epigastrium or
  hypogastrium.
• Peaks at 4 hours, then migrates to the right
  lower quadrant.
• Nausea and anorexia ensues, followed by
  vomiting. Patients may feel constipated.
• Historical points have been evaluated along
  with physical exam findings.

30
Appendicitis

• Abdominal exam focuses on the following
• --tenderness
• --guarding/rigidity
• --rebound (including Rosving sign)
• --Psoas sign
• --obturator sign
• --rectal exam

31
Special Cases

• Immune suppressed All bets are off.
• Immune suppression can include HIV, diabetes,
  alcoholism, malnutrition, malignancy, chronic
  steroid use, other immunosuppressive therapy (RA,
  post transplant).
• Certain conditions become more common
  perforation of viscus, acute acalculous
  cholecystitis, occult abscess.
• Low threshold to perform imaging (U/S, abd CT).

32
Special Cases

• Spinal cord injury, epidural analgesia
  (delivery, surgery).
• Impaired sensory transmission means that pain
  (if present) is poorly localized.
• Often present with apprehension (something is
  wrong), anorexia, restlessness.
• May manifest as autonomic dysreflexia
  elevation of pulse/BP, headache, reflex sweating
  above level of cord lesion, bladder spasms,
  diarrhea.
• Image the belly when in doubt.

33
Objectives

• By the end of these two didactic sessions,
  participants will be able to
• --describe the components of the complete
  abdominal exam inspection, auscultation,
  percussion, palpation
• --describe specialized maneuvers for detecting
  certain disease states
• --recognize strengths and limitations
  (sensitivity and specificity, likelihood ratios)
  of specialized physical exam maneuvers and
  positive findings

34
In conclusion Quote from Copes

• In many emergency units, I have seen a large
  battery of tests and X-rays ordered, often by a
  triage nurse, before the patient is even examined
  by a physician.
• This is a pernicious but common practice. Not
  only have seriously ill patients gone into shock
  in the radiology department, but the return of
  normal reports has often lulled staff into
  believing that all is well and no serious
  intraabdominal condition exists.
• Physicians should always take a thorough
  history and physical before any tests are
  ordered. Only if this is done will the proper
  tests be ordered.