Angiotensin Converting Enzyme Inhibitors and Angiotensin Receptor Blockers should be discontinued 12 to 24 hours before surgery if taken only for hypertension, as they may produce hypotension, which is not responsive to conventional vasopressors. Statins, Beta Blockers and Steroids should not be stopped abruptly before surgery as their abrupt discontinuation may increase the risk of serious (even life-threatening) complications.