Background: The present study examined how effective epinephrine (EPI), norepinephrine (NOR) and dobutamine (DOB) were for resuscitating dogs subjected to hemorrhagic shock (HS).
Methods: Dogs (n = 42) were randomly assigned to seven test groups: EPI, NOR and DOB infusion with and without HS, and HS dogs with no catecholamine. Following baseline measurements, the dogs were bled to a mean arterial blood pressure of 40 mmHg. After 3 h, the shed blood was reinfused. EPI and NOR (0.1, 0.4 and 1.6 micrograms/kg/min) and DOB (2.5, 5.0 and 10.0 micrograms/kg/min) were given and the dog allowed to stabilize for 30 min. Hemodynamic and blood gas data were obtained at 6 time points (control, shock, resuscitation and after catecholamine infusion).
Results: There was no significant difference in myocardial performance (dP/dt) between the respective shocked and unshocked groups after blood resuscitation. In dogs without catecholamine infusion, CO and SvO2 continued to decline whereas SVR increased. DOB (2.5 to 10.0 micrograms/kg/min) with and without shock improved CO, LV dP/dt, SVR and SvO2. EPI did not further improve CO or SvO2 at infusion rates above 0.1 microgram/kg/min (with and without shock). NOR did not improve SvO2 at any infusion rate (with and without shock) and did not improve CO until the infusion rate was at 0.4 microgram/kg/min (without shock).
Conclusions: This study advocates the use of both volume replacement therapy and DOB for resuscitation of HS dogs.