The effect of intravenous magnesium administration on aortic, right atrial and coronary perfusion pressures during CPR in swine.
OBJECTIVE
To determine the effect of magnesium administration on aortic, right atrial and coronary perfusion pressure (CPP) during cardiopulmonary resuscitation (CPR).


METHODS
Twelve swine weighing 23.2 +/- 3.1 kg were instrumented for CPP, aortic systolic (AOSP) and aortic diastolic (AODP) pressures.


METHODS
Ventricular fibrillation was induced and after 20 min of CPR the animals were allocated to receive epinephrine 0.2 mg/kg, or epinephrine 0.2 mg/kg plus magnesium 0.14 g/kg. Epinephrine was repeated every 5 min. Arterial blood gases were determined during normal sinus rhythm and prior to drug administration.


RESULTS
Pressures were recorded and averaged over four consecutive 5-min intervals following initial drug administration. AOSP, AODP and CPP were compared using an analysis of covariance. AOSP was statistically lower in the group receiving magnesium. There was a trend toward lower AODP and CPP in the group receiving magnesium as well. These statistical differences and trends were absent after adjusting for pressures during normal sinus rhythm and serum bicarbonate prior to drug administration.


CONCLUSIONS
In this model of prolonged cardiac arrest, the administration of magnesium with epinephrine appeared to have a negative effect on aortic pressures during CPR. Further study is needed to determine the confounding effect of serum bicarbonate on the response to epinephrine and magnesium during CPR.
Brown
C G
CG
Department of Emergency Medicine, Ohio State University, Columbus 43210.
Griffith
R F
RF
Neely
D
D
Hobson
J
J
Miller
B
B
D000818:Animals; D001011:Aorta / Q000187:drug effects; D016280:Atrial Function, Right / Q000187:drug effects; D001794:Blood Pressure / Q000187:drug effects* / Q000502:physiology; D016887:Cardiopulmonary Resuscitation / Q000379:methods*; D003326:Coronary Circulation / Q000187:drug effects; D003864:Depression, Chemical; D004837:Epinephrine / Q000008:administration & dosage / Q000627:therapeutic use; D006323:Heart Arrest / Q000628:therapy*; D008274:Magnesium / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D013552:Swine
D008274:Magnesium; D004837:Epinephrine