Effect of vasopressin on brain and cardiac tissue during neonatal cardiopulmonary resuscitation of asphyxiated post-transitional piglets

Background

Epinephrine is currently the only recommended cardio-resuscitative medication for use in neonatal cardiopulmonary resuscitation (CPR), as per consensus of science and treatment recommendations. An alternative medication, vasopressin, may be beneficial, however there is limited data regarding its effect on cardiac and brain tissue following recovery from neonatal CPR.

Aim

To compare the effects of vasopressin and epinephrine during resuscitation of asphyxiated post-transitional piglets on cardiac and brain tissue injury.

Methods

Newborn piglets (n = 10/group) were anesthetized, tracheotomized and intubated, instrumented, and exposed to hypoxia-asphyxia and cardiac arrest. Piglets were randomly allocated to receive intravenous vasopressin (Vaso, 0.4 U/kg) or epinephrine (Epi, 0.02 mg/kg) during CPR until return of spontaneous circulation (ROSC). Left ventricle cardiac tissue, and frontoparietal cerebral cortex and thalamus samples from brain tissue were collected from piglets that survived four hours after ROSC. The concentrations of the pro-inflammatory cytokines interleukin (IL)-1β, IL-6, IL-8, and tumour necrosis factor (TNF)-α, cardiac troponin-1, lactate, and levels of oxidized and total glutathione were quantified in tissue homogenates.

Main Results

The median time (IQR) to ROSC was 127 (98–162)sec with Vaso and 197 (117–480)sec with Epi (p = 0.07). ROSC rate was 10/10 (100 %) with Vaso and 7/10 (70 %) with Epi (p = 0.21); survival to four hours after ROSC was 10/10 (100 %) with Vaso and 5/7 (71 %) with Epi (p = 0.15). Kaplan-Meier survival curves were significantly different between groups (p = 0.011). Cardiac tissue IL-8 concentration was significantly lower with Vaso than Epi (16.9 (2.94)pg/mg vs. 33.0 (6.75)pg/mg, p = 0.026). All other markers of cardiac and brain tissue injury were similar between Vaso and Epi groups.

Conclusions

Vasopressin is effective in the resuscitation of asphyxiated newborn piglets and is associated with reduced inflammation of the myocardium compared to epinephrine, and there was no evidence of increased tissue injury in the frontoparietal cortex and thalamus regions of the brain. Vasopressin might be a viable alternative to epinephrine during neonatal CPR, but further studies are warranted.