Comparison of intraosseous and intravenous routes of anticonvulsant administration in a porcine model.
During status epilepticus, rapid IV access for the administration of anticonvulsant drugs can be a very difficult and time-consuming procedure. Our study evaluated whether therapeutic serum levels of phenobarbital and phenytoin could be obtained by the intraosseous route. Twenty domestic swine weighing 10 to 20 kg were divided into two groups (ten each). In one group, phenobarbital 20 mg/kg was administered either intravenously (five) or intraosseously (five). The second group received phenytoin 15 mg/kg either intravenously (five) or intraosseously (five). All animals had samples for anticonvulsant levels drawn from an indwelling arterial cannula at one, three, five, seven, ten, 15, and 30 minutes after dosing. Anticonvulsant levels were found to be statistically significantly higher with IV administration (P less than .01). However, phenobarbital levels were therapeutic by the intraosseous route, while phenytoin levels were below the therapeutic range after the ten-minute interval. Bone marrow levels 45 minutes after infusion were 13.5 micrograms/mL (phenobarbital) and 11.5 micrograms/mL (phenytoin). Our study demonstrates that current IV dosing of phenobarbital 20 mg/kg given intraosseously obtains and maintains therapeutic serum levels. Phenytoin 15 mg/kg does not maintain therapeutic levels and cannot be recommended for intraosseous administration.
Jaimovich
D G
DG
Pediatric Intensive Care Service, Michigan State, Kalamazoo 49007.
Shabino
C L
CL
Ringer
T V
TV
Peters
G R
GR
D000818:Animals; D001794:Blood Pressure; D001853:Bone Marrow; D005454:Fluorescence Polarization; D006339:Heart Rate; D007118:Immunoassay; D007267:Injections; D007275:Injections, Intravenous; D010634:Phenobarbital / Q000008:administration & dosage* / Q000097:blood; D010672:Phenytoin / Q000008:administration & dosage* / Q000097:blood; D013552:Swine; D013977:Tibia; D013997:Time Factors
D010672:Phenytoin; D010634:Phenobarbital