“…Inhalation anaesthetics, sodium nitroprusside (SNP), nitroglycerin, trimethaphan camsilate, alprostadil, adenosine, remifentanil and drugs used in spinal anaesthesia can be fully used alone, whereas calcium channel blockers, β-adrenoreceptor blockers and fenoldopam are used either alone or in combination with other agents [18]. Ideal hypotensive anaesthetic drug must include rapid onset, easy administration, rapid elimination without toxic metabolites, quick wearing off of the effects after discontinuation, dose dependent and the irrelevant effects on vital organs [29]. However, the ideal agent does not exist, therefore the adverse effects of DH almost entirely depend on the drugs used to induce hypotension.…”