Catching fatal memory errors

I'm building a custom Drush command. I want to trigger some code to be executed on a fatal error like:

Drush command terminated abnormally due to an unrecoverable error.                                         [error]
Error: Allowed memory size of 67108864 bytes exhausted (tried to allocate 71 bytes) in
/opt/drush/includes/backend.inc, line 171

How can I catch this error and perform some tasks?