Artificial organs
-
Ultrasound image and augmented reality guidance for off-pump, closed, beating, intracardiac surgery.
Our project is the reintroduction of off-pump intracardiac surgery using the Universal Cardiac Introducer (UCI) for safe intracardiac access. The purpose of this study was to evaluate multimodality visualization using three ultrasound modalities and ultrasound augmented with virtual reality. Image guidance was tested on implanting a mitral valve prosthesis via the UCI in 12 pigs. ⋯ Positioning of the clip was difficult because of artifacts with multiple reflections and shadowing. Augmented reality displayed the entire prosthesis and the tools without artifacts; provided intuitive information on navigation, positioning, and orientation of tools; and improved significantly image guidance and surgical skill. Augmented virtual reality, with tracked 2-D or 3-D ultrasound imaging, provides guidance that can effectively substitute for direct vision during beating heart intracardiac surgery.
-
The aim of this study was to determine the optimal positive end-expiratory pressure (PEEP) required during extracorporeal lung membrane support (interventional lung assist [iLA]; Novalung GmbH, Hechingen, Germany). Twenty healthy pigs were initially (4 h) mechanically ventilated with a tidal volume (V(T)) of 10 mL/Kg, respiratory rate (RR) of 20 breaths/min, PEEP of 5 cm H(2)O, and fraction of inspired O(2) (FiO(2)) of 1.0. ⋯ Gas exchanges with PEEP < or = 10 cm H(2)O were significantly worse than those with PEEP > 12 cm H(2)O, and this without hemodynamical imbalance. This study suggests that the iLA may provide adequate gas exchange during static ventilation only with PEEP levels > 10 cm H(2)O, and this without pulmonary or systemic hemodynamic imbalance.
-
Particulate embolization remains a serious complication of cardiac surgery. Adverse events associated with particulate embolization affect patient morbidity and long-term survival, and increase the length of hospital stay and the cost of health care. Today, atherosclerosis plays a role in at least two-thirds of all adverse events after coronary artery revascularization, and postoperative stroke is the second most common cause of operative mortality. ⋯ Patients must be carefully assessed before surgery to determine their risk, and if the risk is high, surgeons should consider using newer, innovative devices, and techniques in their operative strategy that have proven to be effective in mitigating some of the potential embolic adverse events. A multifaceted, preventive strategy can make a difference, not only in reducing particulate emboli, but also in reducing morbidity and in lowering the economic burden on the health-care system. This brief review will address three areas of focus that are important for the prevention of particulate embolization: (i) prevalence and morbidity of atherosclerotic disease; (ii) risk factors for adverse neurologic events; and (iii) prevention/mitigation of adverse events for patients undergoing cardiac surgery.
-
Randomized Controlled Trial
Nitric oxide in conjunction with milrinone better stabilized pulmonary hemodynamics after Fontan procedure.
Inhaled nitric oxide (iNO) has been used for patients with increased pulmonary vascular resistance (PVR) shortly after Fontan operation, but repeat deterioration of PVR during or shortly after its withdrawal remains a major concern. Milrinone, a phosphodiesterase type 3 (PDE3) inhibitor, can also reduce PVR for postoperative patients with pulmonary hypertension. We hypothesized that iNO, in conjunction with milrinone, can provide additive benefits for pulmonary hemodynamics and reduce the occurrence of iNO withdrawal failure/rebound. ⋯ Combined application of iNO and milrinone resulted in (i) more significant decrement of CVP (19.6 +/- 3.5% in group iNO + Mil vs. 15.2 +/- 4.6% in group iNO, P < 0.05) and TPG (18.2 +/- 4.8% in group iNO + Mil vs. 15.3 +/- 2.6% in group iNO, P < 0.05), (ii) more significant increment of systolic systemic arterial pressure (8.7 +/- 2.7% in group iNO + Mil vs. 5.2 +/- 3.1% in group iNO, P < 0.05), and (iii) more significant improvement of arterial oxygen saturation (9.3 +/- 3.2% in group iNO + Mil vs. 6.8 +/- 2.8% in group iNO, P < 0.01). Occurrence of iNO withdrawal failure during its weaning or rebound after its discontinuation was significantly lower in group iNO + Mil. The combined use of iNO and milrinone provided additive benefits as compared with exclusive use of iNO for patients with elevated PVR after Fontan procedure.