Table 1.

Inclusion and exclusion criteria

Inclusion criteria	Exclusion criteria
Age, 20-50 years	Smoker
Voluntary participation after consent	Blood dyscracias
Having all ten intact digits in both upper limbs	DM/HTN/COPD
Negative Allens’ test	On any chronic medication
No clinical anemia/ictreus	Pregnancy
	Peripheral vascular disease or trauma
	Use of nail paint/digital pigmentation