Improved survival after resuscitation with norepinephrine in a murine model of uncontrolled hemorrhagic shock.
BACKGROUND
Recent studies have challenged current guidelines on fluid resuscitation. However, studies on resuscitation using norepinephrine in uncontrolled hemorrhagic shock are lacking. The authors examined the effects of norepinephrine in combination with saline infusion in uncontrolled hemorrhage in rats.


METHODS
Rats subjected to a 15-min controlled hemorrhage (withdrawal of 3 ml blood/100 g body mass) followed by a 60-min uncontrolled hemorrhage (75% tail amputation) were randomly assigned to one of several treatment groups (10 rats/group) receiving different doses of norepinephrine (0 [NE0], 5 [NE5], 50 [NE50], or 500 [NE500] microg.100 g(-1).h(-1)). In the four hypotensive resuscitation groups (n = 40), mean arterial pressure was not allowed to fall below 40 mmHg by titrated infusion of normal saline. In the four normotensive resuscitation groups (n = 40), it was not allowed to fall below 80 mmHg. The endpoint was survival at 210 min.


RESULTS
There was a significant difference (P < 0.05) in survival rate among groups. Among the hypotensive rats, 6 (60%) survived in the NE0 and NE5 dose groups, 9 (90%) survived in the NE50 dose group, and none survived in the NE500 dose group. Among the normotensive rats, none survived in the NE0 group, 4 (40%) survived in the NE5 dose group, all 10 (100%) survived in the NE50 group, and none survived in the NE500 group.


CONCLUSIONS
The early use of norepinephrine in uncontrolled hemorrhagic shock in rats significantly improved survival when infused at a rate of 50 microg.100 g(-1).h(-1) in normotensive and hypotensive resuscitation strategies.
Poloujadoff
Marie-Pierre
MP
Hôpital Avicenne, Assistance Publique-Hôpitaux de Paris, Université Paris 13, France.
Borron
Stephen W
SW
Amathieu
Roland
R
Favret
Fabrice
F
Camara
Mamadou S
MS
Lapostolle
Frédéric
F
Vicaut
Eric
E
Adnet
Frédéric
F
D000818:Animals; D001784:Blood Gas Analysis; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology; D001810:Blood Volume / Q000502:physiology; D016887:Cardiopulmonary Resuscitation; D003627:Data Interpretation, Statistical; D006339:Heart Rate / Q000187:drug effects / Q000502:physiology; D009638:Norepinephrine / Q000627:therapeutic use*; D051381:Rats; D012771:Shock, Hemorrhagic / Q000188:drug therapy* / Q000401:mortality / Q000503:physiopathology; D013534:Survival; D014662:Vasoconstrictor Agents / Q000627:therapeutic use*
D014662:Vasoconstrictor Agents; D009638:Norepinephrine