The effects of norepinephrine on hemodynamics and renal function in severe septic shock states.

OBJECTIVE: To investigate the effect of norepinephrine (NE) on hemodynamics, oxygen metabolism and renal function in patients with severe septic shock.

DESIGN: Prospective study.

SETTING: Post-operative ICU in a municipal general hospital.

PATIENTS: The study included 56 patients with extreme low resistance states due to abdominal sepsis, who remained hypertensive (MAP < 60 mmHg) despite optimal fluid therapy and dopamine > 20 micrograms/kg/min and cumulative doses of dopamine and dobutamine > 30 micrograms/kg/min, respectively.

INTERVENTIONS: After registration of baseline values dopamine was reduced to 2.5 micrograms/kg/min, and norepinephrine was administered starting at a dose of 0.05 micrograms/kg/min until a mean arterial pressure of more than 60 mmHg could be maintained.

MEASUREMENTS AND RESULTS: During norepinephrine infusion (dosage ranging between 0.1-2 micrograms/kg/min, mean dose rate: 0.4 micrograms/kg/min) mean arterial pressure and systemic vascular resistance index increased significantly (p < 0.001). After 8 h a significant increase in stroke volume (p < 0.05) and decrease in heart rate (p < 0.05) could be observed. There was no significant change in cardiac index (CI), oxygen delivery (O2AVI) and oxygen consumption (VO2I). Creatinine clearance increased significantly (p < 0.005) from a control value of 75 +/- 37 ml/min to 102 +/- 43 ml/min after 48 h NE-treatment.

CONCLUSION: Our results suggest that norepinephrine can be used safely in the treatment of severe septic shock states. Mean arterial pressure and glomerular filtration rate improved markedly without deleterious effects on CI, O2AVI and VO2I.