Hemodynamic effects of association of vasopressin and norepinephrine in patients with septic shock

Introduction

Patients in septic shock (SS) produce inappropriately low amounts of vasopressin [1]. The purpose of our study was to analyze hemodynamic effects of association of exogenous arginine vasopressin (VP) and low doses of norepinephrine (NE) in critically ill patients with septic shock.

Methods

We included patients in SS receiving NE (>0.2 μg/kg/min), and patients with high risk for cardiovascular complications were excluded. VP was given by continuous infusion at a starting dose between 0.01 and 0.04 U/min during 48 hours. VP was titrated to maintain mean arterial pressure (MAP) ≥ 70 mmHg. The following hemodynamic data were recorded at different time points during 2 days: MAP, heart rate, cardiac index (CI) (monitored by Swan–Ganz catheter), arterial lactate, NE doses and creatinine clearance. Statistical analysis was performed using SPSS software for windows version 13 and the Wilcoxon test. P < 0.05 was considered significant.

Results

Seventeen patients were included in this study. Numerical results are presented as means (Table 1). NE was weaned to 0 μg/min in 47% of cases within 44 ± 25 hours. A significant increase in platelet amount was found within 48 hours of starting VP (231 ± 28 vs 134 ± 28, P = 0.009). Creatinine clearance increased at day 3 of therapy (49 ± 7 vs 70 ± 30, P = 0.04). Modifications of lactates were not significant. Reversible cardiac ischemia was noted in two cases.

Table 1 Changes of hemodynamic parameters after arginine vasopressin

Conclusion

These preliminary results showed that VP administration increases the MAP, decreases the CI, gradually decreases the NE dose and improves creatinine clearance in patients with septic shock.