Abdominal Examination Routine — Short Answer Question

SAQ 1 — The Systematic Abdominal Examination Short Case (20 marks, 30 minutes)

Model Answer

(a) The twelve-step sequence and the rationale for auscultating before palpation (4 marks): [1]

The abdominal examination is a reproducible head-to-toe twelve-step routine: end of bed, hands, arms, face, neck, chest, inspection, auscultation (before palpation), palpation (light then deep, starting away from pain), percussion, additional examination (hernial orifices, PR, genitalia, stoma), and legs. [1]

The unique feature of the abdominal examination — in contrast to the cardiovascular and respiratory examinations — is that auscultation precedes palpation. The rationale is physiological: palpation and percussion physically disturb the bowel, potentially stimulating peristalsis and creating artefactual hyperactive sounds, or suppressing peristalsis and creating artefactual silence. Heart murmurs and breath sounds are generated by organs not mechanically altered by the examiner's hands, so the inspect-palpate-percuss-auscultate sequence is appropriate for those systems. Every examiner watches for this: the candidate who palpates before auscultating has demonstrated they do not understand the basis for the sequence change. [1]

(b) Interpretation of palmar erythema, spider naevi, and Dupuytren contracture (4 marks): [1]

Palmar erythema is a diffuse, blanchable erythema of the thenar and hypothenar eminences sparing the centre of the palm. It results from oestrogen excess due to impaired hepatic metabolism, causing peripheral vasodilation. It is non-specific (also seen in pregnancy, rheumatoid arthritis, hyperthyroidism) but supports chronic liver disease in context. [1]

Spider naevi are bright red, radiating vascular lesions with a central arteriole and capillary branches. The diagnostic test is blanching: press the centre with a glass slide and the entire lesion blanches, then refills from the centre outward. The distribution rule is critical: they appear only in the territory of the superior vena cava — face, neck, upper chest, shoulders, arms. More than five in the SVC distribution is significant. The Udell systematic review found spider naevi have a specificity of approximately 95 per cent for cirrhosis in the appropriate clinical context [5]. They also occur in pregnancy and with oral contraceptive use (both oestrogen-excess states).

Dupuytren contracture is thickening and nodularity of the palmar fascia with progressive flexion contracture of the digits (classically ring and little fingers). It is associated with cirrhosis (especially alcoholic), epilepsy, diabetes, and manual labour. The association with liver disease is through a shared fibrogenic pathway. [1]

(c) Differentiation of hepatomegaly, splenomegaly, and a left renal mass (4 marks): [1]

Hepatomegaly is examined from the right iliac fossa, with the hand moving toward the right costal margin on inspiration. The liver edge is described by four characteristics: size (centimetres below the costal margin plus the percussion span in the midclavicular line, normally 10 to 12 cm), surface (smooth versus hard and nodular), edge (sharp versus rounded versus irregular), and tenderness [3].

Splenomegaly is examined from the right side of the patient, starting in the right iliac fossa and moving diagonally toward the left costal margin. The spleen is dull to percussion, has a notch on its medial border, and you cannot get above it. [1]

A left renal mass is ballotable (flick between two hands, one anterior and one in the renal angle), you can get above it (it arises retroperitoneally), and it is resonant to percussion (because of overlying stomach or colonic gas). The Grover systematic review found these physical manoeuvres have moderate sensitivity and that clinical assessment of splenomegaly is imperfect — a non-palpable spleen does not exclude enlargement [2].

(d) Shifting dullness — technique and volume threshold (4 marks): [1]

Shifting dullness is the most reliable bedside sign for ascites. The technique: percuss from the midline outward to the flank in a supine patient. The midline is tympanic (bowel floats on the fluid) and the dependent flanks are dull (fluid pools by gravity). Mark the transition point from tympanic to dull. Ask the patient to roll onto the opposite side and wait 30 seconds for the fluid to redistribute. Re-percuss: the previously dull flank should now be tympanic. This shift confirms free intraperitoneal fluid. [1]

Shifting dullness detects approximately 1000 mL or more of ascites [1]. The fluid thrill (fluid wave) is less sensitive but more specific for tense, large-volume ascites (typically over 2000 mL) — it is tested by tapping one flank while the other hand receives the wave, with the edge of one hand on the midline to dampen transmission through subcutaneous fat.

(e) The six errors that fail the abdominal short case (4 marks): [1]

1. Auscultating after palpation — the cardinal error. Always auscultate first.
2. Not differentiating spleen from kidney — cannot get above the spleen, can get above the kidney; spleen is dull, kidney is resonant; spleen has a notch.
3. Starting palpation at the site of pain — always start away from the pain to build rapport and establish a baseline.
4. Omitting the hands, face and neck — the examination is head-to-toe; the stigmata of systemic disease are in the peripheries.
5. Not measuring the liver span by percussion — reporting only centimetres below the costal margin is incomplete; a displaced liver may be palpable without being enlarged.
6. Forgetting to complete the examination — hernial orifices, PR, genitalia, and legs are all part of the complete routine and must be offered. [1]