Hemodynamic impacts of apelin-13 in a neonatal lamb model of septic peritonitis

Background Apelins are potential candidate therapeutic molecules for hemodynamic support. The objective of this study was to assess the hemodynamic impacts of apelin-13 in a neonatal lamb model of septic shock. Methods Lambs were randomized to receive apelin-13 or normal saline. Septic shock was induced by injecting a fecal slurry into the peritoneal cavity. Lambs underwent volume repletion (30 mL/kg over 1 h) followed by intravenous administration of 5 incremental doses (D) of apelin-13 (D1 = 0.039 to D5 = 19.5 µg/kg/h) or normal saline. Results Following fecal injection, mean arterial pressure (MAP) and cardiac index (CI) dropped in both groups ( p < 0.05). The MAP decreased non-significantly from D1 to D5 ( p = 0.12) in the saline group, while increasing significantly ( p = 0.02) in the apelin group (−12 (−17; 12) vs. +15 (6; 23) % ( p = 0.012)). Systemic vascular resistances were higher in the apelin-13 group at D5 compared to the saline group (4337 (3239, 5144) vs. 2532 (2286, 3966) mmHg/min/mL, respectively, p = 0.046). The CI increased non-significantly in the apelin-13 group. Conclusion Apelin-13 increased MAP in a neonatal lamb septic shock model. Impact Administration of apelin-13 stabilized hemodynamics during the progression of the sepsis induced in this neonatal lamb model. Systemic vascular resistances were higher in the apelin-13 group than in the placebo group. This suggests ontogenic differences in vascular response to apelin-13 and warrants further investigation. This study suggests that apelin-13 could eventually become a candidate for the treatment of neonatal septic shock.