How does smoking affect a microdiscectomy ?

No data on smoking a: Smoking has no relation but if you have smoker cough then it can slow healing or delay.

Several ways: Smoking creates a higher risk of wound healing complications and infection. It accelerates the rate of disc degeneration leading to a higher risk of disc herniation. It also leads to poorer outcomes in spine surgery compared to nonsmokers.

Badly.: Smoking lowers oxygen in your blood because carbon monoxide, a by-product of all combustion, is very tightly bound to hemoglobin (200 x more than o2) and your blood cells can't carry as much o2 (oxygen). Lower o2 is not good for healing.