Saturday July 14, 2007
Norepinephrine friend or foe? - probably friend !

As we discussed earlier on this forum (see below related pearls) that overall trend is to use norepinephrine instead of dopamine as first line vasopressor in ICUs.

One step further, in july 2007 issue of Crititical Care medicine 1, laboratory investigation published regarding comparative effects of early versus delayed use of norepinephrine in resuscitated endotoxic shock.

5 groups (each group with 7 rats) were anesthetized, mechanically ventilated, paralyzed, and instrumented to measure mean arterial pressure, heart rate, pulse pressure variation, aortic and mesenteric blood flow, muscle and liver tissue oxygen pressure, blood gas, and lactate. 5 groups were

1. endotoxin alone (Endo),
2. endotoxin plus norepinephrine (Endo/NE),
3. endotoxin plus fluid therapy alone (ENDO/Fl),
4. endotoxin plus fluid therapy plus late catecholamine (Endo/Fl/Late NE), and
5. endotoxin plus fluid therapy plus simultaneous norepinephrine administration (Endo/Fl/Early NE)

Results:

• Mean arterial pressure increased to baseline values only in the catecholamine-treated group (p < .05).
• In ENDO/Fl, Endo/Fl/Late NE, and Endo/Fl/Early NE, aortic blood flow was maintained.
• Mesenteric blood flow was maintained at baseline values only in the catecholamine-treated groups
• Mesenteric/aortic blood flow ratio was higher in the early catecholamine group (p < .05)
• Endo and ENDO/Fl were associated with a marked decrease in liver Po2, which was maintained in catecholamine-treated groups (p < .01)
• Plasma lactate was lower in the Endo/Fl/Early NE group
  Volume resuscitation was higher in Endo and
• Endo/Fl/Late NE groups with 28 ± 6 and 27 ± 4 mL, respectively, when compared with the Endo/Fl/Early NE group (19 ± 3 mL) (p < .05)

Conclusions: The use of norepinephrine was associated with improved mean arterial pressure, sustained aortic and mesenteric blood flow, and better tissue oxygenation when compared with fluid resuscitation alone, irrespective of time of administration. The early use of norepinephrine plus volume expansion was associated with a higher proportion of blood flow redistributed to the mesenteric area, lower lactate levels, and less infused volume. Thus, the early use of norepinephrine is safe and may decrease the need for volume resuscitation



Previous Related pearls

Norepinephrine or Dopamine ? ,

Renal Dose Norepinephrine !

Is Dopamine phasing out?




Reference: click to get abstract/article

1. Comparative effects of early versus delayed use of norepinephrine in resuscitated endotoxic shock - Laboratory Investigations, Critical Care Medicine. 35(7):1736-1740, July 2007.
2. Renal Dose Norepinephrine! - Chest. 2004;126:335-337
3. Renal Effects of Norepinephrine in Septic and Nonseptic Patients - Chest. 2004;126:534-539
4. Noradrenaline and the kidney: friends or foes? - Crit Care 2001, 5:294-298
5. Vasopressor and inotropic support in septic shock: An evidence-based review. - Critical Care Medicine. 32(11) Supplement:S455-S465, November 2004