The common procedure of invasive cardiac intervention and intravenous magnesium administration before reperfusion should without question become the gold standard in treatment of acute myocardial infarction.  Two meta-analyses studied the impact of magnesium treatment on reduction of the death rate and rhythm disorders in the acute phase of myocardial infarction before initiation of reperfusion treatments. Both reports found a 54% reduction of the death rate, and one noted a decreased incidence (49% less) of ventricular fibrillation or tachycardia in the population treated by magnesium.  The most important action of MgSO4 in AMI is to open up collateral circulation and relieve ischaemia thus reducing infarct size and mortality rates. 
The influence of renal impairment on the pharmacokinetics of haloperidol has not been evaluated. About one-third of a haloperidol dose is excreted in urine, mostly as metabolites. Less than 3% of administered haloperidol is eliminated unchanged in the urine. Haloperidol metabolites are not considered to make a significant contribution to its activity, although for the reduced metabolite of haloperidol, back-conversion to haloperidol cannot be fully ruled out. Even though impairment of renal function is not expected to affect haloperidol elimination to a clinically relevant extent, caution is advised in patients with renal impairment, and especially those with severe impairment, due to the long half-life of haloperidol and its reduced metabolite, and the possibility of accumulation (see section ).
The intravenous route is not FDA approved and is generally not recommended except when no other alternatives are available. Intravenous administration appears to be associated with a higher risk of QT prolongation and torsade de pointes (TdP) than other forms of administration. The manufacturer recommends ECG monitoring for QT prolongation and arrhythmias if IV administration is required. A dose in the range of 1 to 5 mg IV has been suggested, with the dose being repeated at 30 to 60 minute intervals, if needed. A maximum IV dose has not been established. The lowest effective dose should be used in conjunction with conversion to oral therapy as soon as possible.