A Novel Method to Safely De-Air a HeartWare System in a Single-Ventricle Patient by Utilizing ECMO and a Minimized CPB Circuit.

The survival of congenital heart disease (CHD) patients with single-ventricle (SV) physiology has markedly increased as a result of advances in operative techniques and postsurgical management. Nonetheless, these patients remain highly susceptible to end-stage heart failure requiring cardiac replacement therapies at early ages. Given a worldwide shortage of transplantable organs, mechanical circulatory support (MCS) represents an alternative treatment option. The significant heterogeneity of the SV population presents unique indications for MCS that have begun to be evaluated. This case study describes a 12-year-old female with heterotaxy syndrome and an SV condition, previously palliated with a Fontan operation at another institution. The patient was placed on veno-arterial (VA) extracorporeal membrane oxygenation (ECMO) during prolonged cardiopulmonary resuscitation, and later underwent HeartWare ventricular assist device (HVAD) implantation as a bridge to transplantation (BTT). A novel method was chosen to optimize careful de-airing of the heart through a minimized cardiopulmonary bypass (CPB) setup, during full ECMO support and surgical insertion of the HeartWare. The ascending aorta was vented proximal to the HVAD outflow graft anastomosis through a minimized CPB circuit at <10% of the ECMO flow rate. This circuit adaption allowed for euvolemic resuscitation via connection from the minimized CPB circuit to the venous limb of the ECMO circuit. The transition from VA-ECMO to the HeartWare was well tolerated despite a challenging sternotomy and cardiac anomaly. A minimized bypass circuit proved efficacious for the benefit of volume resuscitation and safe de-airing of the HVAD while on ECMO support. The literature is limited concerning safe practices for implantation of durable VADs in complex SV patients coupled with those transitioning from varying modalities of MCS. As SV survivability regresses to heart failure, it is essential that we share techniques that aim to improve the long-term outcomes for successful BTT or bridge to decision (BTD).

In vitro time- and dose-effect response of JP-8 and S-8 jet fuel on alveolar type II epithelial cells of rats.

This study was designed to characterize and compare the effects of jet propellant-8 (JP-8) fuel and synthetic-8 (S-8) on cell viability and nitric oxide synthesis in cultured alveolar type II epithelial cells of rats. Exposure times varied from 0.25, 0.5, 1, and 6 hours at the following concentrations of jet fuel: 0.0, 0.1, 0.4, and 2.0 microg/mL. Data indicate that JP-8 presents a gradual decline in cell viability and steady elevation in nitric oxide release as exposure concentrations increase. At a 2.0 microg/mL concentration of JP-8, nearly all of the cells are not viable. Moreover, S-8 exposure to rat type II lung cells demonstrated an abrupt fall in percentage cell viability and increases in nitric oxide measurement, particularly after the 2.0 microg/mL was reached at 1 and 6 hours. At 0.0, 0.2, and 0.4 microg/mL concentrations of S-8, percentage viability was sustained at steady concentrations. The results suggest different epithelial toxicity and mechanistic effects of S-8 and JP-8, providing further insight concerning the impairment imposed at specific levels of lung function and pathology induced by the different fuels.