Are perioperative near-infrared spectroscopy values correlated with clinical and biochemical parameters in cyanotic and acyanotic infants following corrective cardiac surgery?

WOS: 000371172200007PubMed ID: 26034194Background: Near-infrared spectroscopy (NIRS) is a useful non-invasive tool for monitoring infants undergoing cardiac surgery. In this study, we aimed to determine the NIRS values in cyanotic and acyanotic patients who underwent corrective cardiac surgery for congenital heart diseases. Methods: Thirty consecutive infants who were operated on with the diagnosis of ventricular septal defect (n=15) and tetralogy of Fallot (n=15) were evaluated retrospectively. A definitive repair of the underlying cardiac pathology was achieved in all cases. A total of six measurements of cerebral and renal NIRS were performed at different stages of the perioperative period. The laboratory data, mean urine output and serum lactate levels were evaluated along with NIRS values in each group. Results: The NIRS values differ in both groups, even after the corrective surgical procedure is performed. The recovery of renal NIRS values is delayed in the cyanotic patients. Conclusion: Even though definitive surgical repair is performed in cyanotic infants, recovery of the renal vasculature may be delayed by up to two days, which is suggestive of a vulnerable period for renal dysfunction

Computational modeling of neonatal cardiopulmonary bypass hemodynamics with full Circle of Willis anatomy

Cardiopulmonary bypass (CPB) procedure is employed to repair most congenital heart defects (CHD). Cannulation is a critical component of this procedure where the location and diameter of cannula controls the hemodynamic performance. State-of-the-art computational studies of neonatal CPB employed an isolated aortic arch region by truncating the three-dimensional (3D) patient-specific cerebral system. The present work expanded these studies where the 3D patient-specific MRI reconstruction of the cerebral system, including the Circle of Willis (CoW), is integrated with a hypoplastic neonatal aortic arch. The inlet of the arterial cannula is assigned a steady velocity boundary condition of the CPB pump, while all outlets are modeled as resistance boundary conditions, thus allowing acute comparisons between different cannula configurations. Three-dimensional (3D) flow simulations in the aortic arch model are performed at a Reynolds number of 2150 using an experimentally validated commercial solver. Results demonstrate that the inclusion of 3D CoW is essential to predict the accurate head-neck blood perfusion and therefore critical in deciding the neonatal aortic cannulation strategy preoperatively. Using this integrated model two CPB configurations are studied, where the cannulas were placed at innominate artery (IA) (IA-cannula configuration) and ductus arteriosus (DA) (DA-cannula configuration). Configuration change produced significant differences in flow splits and local hemodynamics of blood flow throughout the whole aortic arch, neck and cerebral arteries. Percent flow rate differences between the IA- and DA-cannula configurations are computed to be: 19%, for descending aorta, 198% for ascending aorta (perfusing coronary arteries), 91% for right anterior cerebral artery, and 68% for left anterior cerebral artery. Another important finding is the retrograde flow at vertebral arteries for IA-cannula configuration, but not for DA-cannula. These results may help to translate better neonatal arterial cannulae design for minimizing cerebral complications during CPB procedures

Vacuum-assisted Venous Drainage and Gaseous Microemboli in Cardiopulmonary Bypass

When conventional gravity siphon venous drainage cannot achieve satisfactory venous drainage during minimally invasive cardiac and neonatal surgeries, assisted venous drainage techniques are needed to ensure adequate flow. One assisted venous drainage technique, vacuum-assisted venous drainage (VAVD), the aid of a vacuum in the venous reservoir, is now widely used to augment venous drainage during cardiopulmonary bypass (CPB) procedures. VAVD permits the use of smaller venous cannulae, shorter circuit tubing, and lower priming and blood transfusion volumes, but increases risk of arterial gaseous microemboli and blood trauma. The vacuum should be set as low as possible to facilitate full venous return, and realtime monitoring of gaseous microemboli in the arterial and venous line should be used to achieve the safest conditions. With current ultrasound technology, it is possible to simultaneously detect and classify gaseous microemboli in the CPB circuit. In this article, we summarize the components, setup, operation, advantages, and disadvantages of VAVD techniques and clinical applications and describe the basic principles of microemboli detectors, such as the Emboli Detection and Classification (EDAC) Quantifier (Luna Innovations, Roanoke, VA) and Bubble Counter Clinical 200 (GAMPT, Zappendorf, Germany). These novel gaseous microemboli detection devices could help perfusionists locate the sources of entrained air, eliminate hidden troubles, and minimize the postoperative neurologic impairments attributed to gaseous microemboli in clinical practice

Outcomes of the 11(th) International Conference on Pediatric Mechanical Circulatory Support Systems and Pediatric Cardiopulmonary Perfusion

Outputs of the 11th International conference on pediatic mechanical life suppor

Evaluation of Quadrox-i® Adult Hollow Fiber Oxygenator with Integrated Arterial Filter

Gaseous microemboli (GME) remain a challenge for cardiopulmonary bypass procedures in adult as well as pediatric cardiac surgery patients. The present study tested the effectiveness of a new adult membrane oxygenator in models both with and without an integrated arterial filter to evaluate GME trapping capability and determine membrane pressure drops at various flow rates and temperatures. The experimental circuit included a RotaFlow centrifugal blood pump, Quadrox-i® (n = 8) or Quadrox® (n = 8) adult microporous membrane oxygenator, and Sorin adult tubing package. A Sorin Cardiovascular® VVR® 4000i venous reservoir served as pseudo-patient. The circuit was primed with 900 mL heparinized human red blood cells and 300 mL Lactated Ringer’s solution. The final hematocrit was 36%. Tests were performed at different flow rates (4 L/min, 5 L/min, and 6 L/min) and temperatures (35° and 30°). Five mL of bolus air was injected into the venous line over 15 seconds using a syringe connected to a 3/8 × 1/2 luer connector. The Quadrox-i® adult microporous membrane oxygenator with integrated arterial filter had a similar pressure drop at 4 L/min and 35°C compared with Quadrox® membrane oxygenator whereas it had higher pressure drops at 5 L/min and 6 L/min (p <.001). Quadrox-i® adult microporous membrane oxygenator reduced the total emboli count and total emboli volume delivered to the pseudo-patient at all flow rates (p <.001). The emboli handling of Quadrox-i® adult microporous membrane oxygenator was not affected by flow rate and temperature. Compared with the traditional Quadrox® oxygenator, Quadrox-i® adult microporous membrane oxygenator with integrated arterial filter and Softline coating has improved GME handling capacity