Retrospective analysis of eliminating modified ultrafiltration after pediatric cardiopulmonary bypass.

Modified ultrafiltration (MUF) is a technique which is commonly used immediately post-cardiopulmonary bypass (CPB) for open heart surgery in children. There are many advantages of MUF, but there are also a number of less reported disadvantages. At our institution, after considering all of the available data, a decision was made to no longer perform MUF. The primary motivation being the simplified and miniaturized CPB circuit would reduce hemodilution, decrease our likelihood of reaching our transfusion trigger during CPB and, potentially, improve safety. This study reports the before and after data from this practice change. A total of 160 patients less than 8kg were studied over 38 months and divided into neonatal and pediatric cohorts. Parameters reported in this study include: demographics, hematocrit, blood product transfusion, hemostasis, hemodynamics and outcomes. Although retrospective, our analysis supports an advantage of preventing hemodilution (via circuit miniaturization) versus reversing hemodilution (via MUF) at our institution with the patient population we examined.

Recent Advances in Pediatric Cardiopulmonary Bypass.

There have been numerous recent advances geared specifically toward the practice of pediatric cardiopulmonary bypass (CPB). These advances include the development of the first oxygenator intended solely for the neonatal CPB patient; pediatric oxygenators with low prime volumes and surface areas, which allow flows up to 2 L/min; pediatric oxygenators with integrated arterial filters; and miniature ultrafiltration (UF) devices, which allow for high rates of ultrafiltrate removal. When used in combination with heart lung machines with mast-mounted pumps, these advances can result in significant decreases in CPB circuit surface areas and prime volumes. This may attenuate CPB-associated hemodilution and decrease or eliminate the need for homologous red blood cells during or after CPB. In addition to these equipment-related advances, changes in myocardial protection strategies and the technique of modified UF as it relates to these advances are discussed.

Complications relating to perfusion and extracorporeal circulation associated with the treatment of patients with congenital cardiac disease: consensus definitions from the Multi-Societal Database Committee for Pediatric and Congenital Heart Disease.

The International Consortium for Evidence-Based Perfusion (www.bestpracticeperfusion.org) is a collaborative partnership of societies of perfusionists, professional medical societies, and interested clinicians, whose aim is to promote the continuous improvement of the delivery of care and outcomes for patients undergoing extracorporeal circulation. Despite the many advances made throughout the history of cardiopulmonary bypass, significant variation in practice and potential for complication remains. To help address this issue, the International Consortium for Evidence-Based Perfusion has joined the Multi-Societal Database Committee for Pediatric and Congenital Heart Disease to develop a list of complications in congenital cardiac surgery related to extracorporeal circulation conducted via cardiopulmonary bypass, extracorporeal membrane oxygenation, or mechanical circulatory support devices, which include ventricular assist devices and intra-aortic balloon pumps. Understanding and defining the complications that may occur related to extracorporeal circulation in congenital patients is requisite for assessing and subsequently improving the care provided to the patients we serve. The aim of this manuscript is to identify and define the myriad of complications directly related to the extracorporeal circulation of congenital patients.

Methylene blue-induced methemoglobinemia during cardiopulmonary bypass? A case report and literature review.

The guanylate cyclase (GC) and inducible nitric oxide (iNOS) inhibitor methylene blue (MB) has been used in cardiac surgery patients for the treatment of a variety of conditions. Methylene blue has been successfully used for the prevention and treatment of vasoplegia syndrome (VS) in patients undergoing cardiac surgery with cardiopulmonary bypass (CPB). Vasoplegia syndrome occurs in up to 10% of cardiac surgery patients and is associated with poor clinical outcomes. Vasoplegia syndrome is described along with the results of studies that have shown benefits of MB in the treatment of VS. These studies include the use of MB prior to CPB, when added to the CPB prime and when given into the CPB circuit during the operation. We report a case of emergency CPB on a 55-year-old male with bacterial endocarditis, scheduled for an AVR/MVR who arrested on arrival to the operating room. Once on CPB the patient developed a profound hypotension despite normal to high pump flows, with low systemic vascular resistance (SVR), which was refractory to vasopressors--consistent with a diagnosis of VS. Unbeknownst to the perfusionist, the patient was treated with MB which was immediately followed by an apparent sudden arterial desaturation, despite oxygenator ventilation with 100% oxygen (O2), and development of severe metabolic acidosis. Troubleshooting the cause of the apparent desaturation and eventual diagnosis of a false indication of arterial oxygen desaturation and methemoglobinemia (MHgb) due to MB injection is described. Methemoglobinemia is explained as well as its presentation and treatment with MB. The importance of intraoperating room communication and knowledge of drug effects are discussed.