Comparison of intravenous and intranasal administration of epinephrine during CPR in a canine model

Study objectives: Epinephrine improves coronary perfusion pressure during CPR. However, administration of epinephrine during CPR may be delayed or omitted if IV or endotracheal access is not established. Therefore, the objective of this study was to determine if intranasal administration of epinephrine during CPR would provide an alternate route of drug administration that is readily accessible and requires no special technical skills. Design and setting: Randomized blinded study performed in a controlled laboratory environment. Type of participants: Twenty mongrel dogs weighing 19.5 ± 4.6 kg. Interventions: All dogs received either IV epinephrine 0.015 mg/kg or intranasal epinephrine 14mg per nostril. Phentolamine (5mg per nostril) was administered intranasally one minute before nasal administration of epinephrine to improve absorption. Each dog underwent three minutes of ventricular fibrillation followed by seven minutes of CPR with a pneumatic chest compression device. Epinephrine was administered at two minutes into CPR. Measurements and main results: Seven dogs were excluded because of inadequate baseline coronary perfusion pressure or compression device displacement, leaving a total of 13 dogs for analysis (six IV epinephrine, seven intranasal epinephrine). Baseline coronary perfusion pressure (mean ± SD) was similar for IV epinephrine and intranasal epinephrine (16.9 ± 7.1 mm Hg versus 18.2 ± 13.8mm Hg, respectively, P = .84). For IV and intranasal epinephrine, coronary perfusion pressure increased to 21.4 ± 9.2 mm Hg and 24.4 ± 18.7 mm Hg one minute after epinephrine, respectively (P = .73). Five minutes after epinephrine coronary perfusion pressure was 18.2 ± 8.7 mm Hg and 24.3 ± 13.9 mm Hg for IV epinephrine and intranasal epinephrine, respectively (P = .38). The rate of successful resuscitation was similar for both groups, five of seven dogs for intranasal epinephrine and four of six dogs for IV epinephrine (P = .66). Conclusion: Intranasal epinephrine has similar effects on coronary perfusion pressure and resuscitation compared with standard-dose IV epinephrine. Therefore, the nasal route for administration of epinephrine appears to be an acceptable alternate method of drug delivery during CPR and compares favorably with standard IV therapy in the canine model. Because of the obvious benefits to human patients, these observations suggest further investigation.