Objective: To investigate the specific hemodynamic effects of the phosphodiesterase inhibitor milrinone in a rabbit model of septic shock in the absence of any other treatment.
Design: A prospective, controlled, interventional study.
Animal Model: Fourteen sedated New Zealand rabbits.
Setting: Research laboratory of a health sciences university.
Interventions: Rabbits were anesthetized and vascular catheters inserted in femoral artery and jugular vein. After a stabilization period and the recording of baseline measurements (H0), all animals received a 10-mL infusion of Pseudomonas aeruginosa. Two hours later (H2rabbits were randomly assigned to receive 5% dextrose (control group) or milrinone (milrinone group).
Measurements and Main Results: Mean arterial blood pressure (MAP) was monitored continuously, and a cardiac index (CI) was determined every 30 mins by a transpulmonary thermodilution technique using an integrated monitoring device (PICCO). No differences were detected between the two groups after stabilization (H0) or before the treatment (H2) for either CI (mL/min-1/kg-1) or MAP (mm Hg). CI decreased progressively in the control group during the following 4 hrs, but not in the treated group (at H6: 122 ± 4 vs. 207 ± 16 mL/min-1/kg-1; p < .05). No drop of MAP occurred after milrinone infusion. A comparison of the treated and control group reveals that milrinone improved tissue perfusion as evidenced by measurements of central venous saturation (at H4: 0.59 ± 0.05 vs. 0.71 ± 0.03, p = .04), lactacidemia (at H6: 10.3 ± 2.4 vs. 3.9 ± 0.9 mmol/L, p = .03), creatinemia (at H6: 95 ± 11 vs. 60 ± 5 μmol/L, p = .02) and survival (at H6: 5 vs. 7, not significant).
Conclusion: Milrinone improves cardiac output and tissue perfusion in a rabbit model involving severe septic shock.
From the Pediatric Intensive Care Unit (JML, CGL, JCR) and the Department of Medical Biochemistry (JLO), University Hospital of Nantes, Nantes, France, UPRES EA 1156: Thérapeutiques Cliniques et Expérimentales des Infections, University of Nantes, Nantes, France.
All authors have no financial interests to disclose.