Best site to demonstrate capillary filling in infants –
The state of microcirculation can be assessed by capillary filling time (CFT)
Firm pressure is applied over sternum or forehead by a ball of the thumb for 5 seconds. This leads to blanching.
On removal of pressure color returns. The time taken for complete return of color is designated as capillary filling time, the normal is less than or equal to 3 sec.
Prolonged CFT is the earliest sign signifying impairment or microcirculation.
Nail bed
Sternum
Ear lobule
Great toe