Effects of norepinephrine and dobutamine on pressure load-induced right ventricular failure

Crit Care Med. 2004 Apr;32(4):1035-40. doi: 10.1097/01.ccm.0000120052.77953.07.


Objective: A transient increase in pulmonary arterial (PA) pressure can persistently depress right ventricular (RV) contractility. We investigated the effects norepinephrine and dobutamine on RV-PA coupling in this model of RV failure.

Design: Prospective, controlled, randomized animal study.

Setting: University research laboratory.

Subjects: Twenty-two anesthetized dogs.

Interventions: Animals underwent transient (90-min) PA constriction to induce persistent RV failure. They were randomly assigned to control, norepinephrine, or dobutamine group. Norepinephrine was administered at 0.1 and 0.5 microg x kg x min or dobutamine at 5 and 10 microg x kg x min.

Measurements and main results: We measured PA distal resistance and proximal elastance by pressure-flow relationships and vascular impedance. We also measured RV contractility by the end-systolic pressure-volume relationship (Ees), PA effective elastance by the end-diastolic to end-systolic relationship (Ea), and RV-PA coupling efficiency by the Ees/Ea ratio. The transient PA constriction persistently increased PA resistance and elastance, increased Ea from 0.8+/-0.1 to 2.7+/-0.3 mmHg/mL, decreased Ees from 1.1+/-0.1 to 0.5+/-0.1 mm Hg/mL, and decreased Ees/Ea from 1.2+/-0.1 to 0.2+/-0.1. Norepinephrine restored arterial pressure, increased RV contractility, and increased but did not normalize RV-PA coupling and cardiac output. Dobutamine restored arterial pressure, markedly increased RV contractility, and normalized RV-PA coupling and cardiac output. Compared with norepinephrine, dobutamine decreased PA resistance and elastance and increased RV contractility and RV-PA coupling.

Conclusions: A transient increase in PA pressure persistently worsens PA hemodynamics, RV contractility, RV-PA coupling, and cardiac output. Dobutamine restores RV-PA coupling and cardiac output better than norepinephrine because of its more pronounced inotropic effect.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Blood Pressure / drug effects*
  • Blood Pressure / physiology
  • Cardiotonic Agents / pharmacology*
  • Dobutamine / pharmacology*
  • Dogs
  • Hypertension, Pulmonary / physiopathology*
  • Myocardial Contraction / drug effects*
  • Myocardial Contraction / physiology
  • Norepinephrine / pharmacology*
  • Pulmonary Wedge Pressure / drug effects
  • Pulmonary Wedge Pressure / physiology
  • Stroke Volume / drug effects*
  • Stroke Volume / physiology
  • Vascular Resistance / drug effects
  • Vascular Resistance / physiology
  • Ventricular Dysfunction, Right / physiopathology*


  • Cardiotonic Agents
  • Dobutamine
  • Norepinephrine