Infant’s finger examination

Also finger vein examination. A diagnostic method based on observation of the veins in the fingers of children, developed by Wang Chao of the Táng Dynasty, and further refined by Chen Fu-Zheng in The Young Child Compendium (幼幼集成 yòu yòu jí chéng). The examination of the finger veins has considerable clinical value in diagnosing children below the age of three, before natural thickening of the skin makes the veins indistinct. The finger examination provides supplementary diagnostic data that is particularly useful in judging the severity of disease. It also helps to compensate for difficulties of pulse examination due to the infant’s very short radial pulse, which must be taken with only one finger, and to disturbances of the pulse that result from the distress commonly experienced by infants in unfamiliar surroundings.

The greater yīn (tài yīn) lung channel runs from the chest through the inch, bar, and cubit, and through the fish’s margin (thenar eminence) to the tip of the thumb. The veins of the inner side of the index finger lie on a branch that separates from the main channel at a point proximal to the wrist, and provide diagnostic data that accords with that of the radial pulse.

The finger is divided into three segments, known as bars.

• The first segment, from the metacarpophalangeal joint to the proximal interphalangeal joint is known as the wind bar.
• The second, from the proximal interphalangeal joint to the distal interphalangeal joint, is known as the qì bar.
• The final segment, from the distal interphalangeal joint to the fingertip, is called the life bar.

The examination should be conducted with the child facing a good light source (sunlight being preferable to electric light). The practitioner holds the child’s index finger in his left hand, and rubs it several times with the right hand from the life bar down to the wind bar, to enable the veins to stand out more clearly. In healthy infants, the veins appear as dimly visible, pale purple, or reddish-brown lines. Generally, they are only visible in the wind bar. In sickness, the color and degree of fullness of the veins may undergo change. The depth, color, paleness, stagnation, and length are examined.

Depth: Veins that are particularly distinct and close to the surface indicate an exterior pattern. An external evil is assailing the exterior, and right qì is trying to resist, hence qì and the blood tend toward the surface. Veins that appear deep and only dimly visible indicate the presence of an evil in the interior.

Color: Bright red usually indicates wind-cold. Purple-red indicates interior heat; pale yellow indicates spleen vacuity; purple black reflects depression in the blood network vessels and indicates a severe or critical condition. A green-blue coloring is observed in fright wind and pain patterns. Black generally indicates blood stasis. Pale veins are a vacuity sign.

Stagnation: Veins of a stagnant complexion (i.e., visually discernible impairment of blood flow) are associated with repletion patterns such as phlegm-damp, food stagnation, or binding depression of evil heat.

Length: The longer the visible veins, the more severe the disease. If the veins are distinct only in the wind bar, the condition is relatively mild. If they are also distinct in the qì bar, the condition is more severe. The infant’s life may be in jeopardy if veins become distinct in the life bar (hence its name). Extension of visible veins through all the bars to the fingertip is the mark of a critical condition. In external contractions, visible veins confined to the wind bar indicate invasion of the network vessels. If they extend into the qì bar and are deeper in color, the evil has entered the channels. Extension into the life bar marks penetration into the bowels and viscera.