Jade template engine - Each Iteration Offset
each item, i in list li= item if i === 1 | : First item in list!
If @Johnathan's answer does not work for you:In Jade 1.7 the following works:
for item, i in list li= item if i === 0 | : First item in list!
http://www.learnjade.com/tour/iteration/
Also note the 0 index vs 1 index.