Cardiovascular effects of enoximone and epinephrine on heparin reversal with protamine in conscious dogs.
OBJECTIVE
To compare enoximone with epinephrine as treatments for the cardiotoxic effects of protamine sulfate.


METHODS
Prospective randomized study.


METHODS
12 healthy cross-bred dogs weighing 23 +/- 4 kg.


METHODS
The dogs were anesthetized with xylazine and ketamine to allow instrumentation. Femoral arterial and venous catheters were inserted for pressure monitoring and to allow drug infusion. A thermodilution catheter mounted with a fast response thermistor was inserted into the pulmonary artery via the jugular vein to measure cardiac output and right ventricular volumes. Heparin 300 units/kg followed by protamine 4.5 mg/kg were administered 45 minutes after the xylazine/ketamine. Four animals were not treated (controls), four received enoximone, and four were given epinephrine. Cardiopulmonary parameters were monitored for a period of 30 minutes.


RESULTS
Cardiac index was 104 +/- 15 mL/kg/min in the enoximone group, 72 +/- 13 mL/kg/min in the epinephrine group, and 63 +/- 10 mL/kg/min in the control group (P < .05 enoximone versus control and epinephrine). Right ventricular end systolic volume was 18 +/- 3, 27 +/- 4, and 29 +/- 6 mL in the enoximone, epinephrine, and control groups (P < .05 enoximone versus control and epinephrine). There were no differences in mean arterial pressure or pulmonary and systemic vascular resistance between the groups.


CONCLUSIONS
In this study, enoximone was more effective than epinephrine at reversing the hemodynamic changes associated with protamine sulfate administration.
Saritas
Z
Z
Department of Surgery, Ankara University, Veterinary Faculty, Turkey.
Samsar
E
E
Gökge
P
P
Katircioglu
S F
SF
D000818:Animals; D002316:Cardiotonic Agents / Q000494:pharmacology*; D002319:Cardiovascular System / Q000187:drug effects*; D003243:Consciousness / Q000502:physiology; D004285:Dogs / Q000502:physiology*; D017335:Enoximone / Q000494:pharmacology*; D004837:Epinephrine / Q000494:pharmacology*; D006439:Hemodynamics / Q000187:drug effects; D006494:Heparin Antagonists / Q000009:adverse effects*; D011446:Prospective Studies; D011479:Protamines / Q000009:adverse effects* / Q000037:antagonists & inhibitors; D014662:Vasoconstrictor Agents / Q000494:pharmacology*
D002316:Cardiotonic Agents; D006494:Heparin Antagonists; D011479:Protamines; D014662:Vasoconstrictor Agents; D017335:Enoximone; D004837:Epinephrine